[PATCH v3 0/4] mxs-lradc: Split driver into MFD

[PATCH v3 0/4] mxs-lradc: Split driver into MFD

[Ksenija Stanojevic]

Split existing driver mxs-lradc into MFD with touchscreen and
IIO part.

Tested on i.MX28.

Ksenija Stanojevic (4):
  mfd: mxs-lradc: Add support for mxs-lradc MFD
  iio: adc: mxs-lradc: Add support for adc driver
  input: touchscreen: mxs-lradc: Add support for touchscreen
  iio: adc: mxs-lradc: Remove driver

 drivers/iio/adc/Kconfig                  |   27 +-
 drivers/iio/adc/Makefile                 |    2 +-
 drivers/iio/adc/mxs-lradc-adc.c          |  811 ++++++++++++++
 drivers/iio/adc/mxs-lradc.c              | 1775 ------------------------------
 drivers/input/touchscreen/Kconfig        |   10 +
 drivers/input/touchscreen/Makefile       |    1 +
 drivers/input/touchscreen/mxs-lradc-ts.c |  729 ++++++++++++
 drivers/mfd/Kconfig                      |   17 +
 drivers/mfd/Makefile                     |    1 +
 drivers/mfd/mxs-lradc.c                  |  217 ++++
 include/linux/mfd/mxs-lradc.h            |  204 ++++
 11 files changed, 2004 insertions(+), 1790 deletions(-)
 create mode 100644 drivers/iio/adc/mxs-lradc-adc.c
 delete mode 100644 drivers/iio/adc/mxs-lradc.c
 create mode 100644 drivers/input/touchscreen/mxs-lradc-ts.c
 create mode 100644 drivers/mfd/mxs-lradc.c
 create mode 100644 include/linux/mfd/mxs-lradc.h

-- 
1.9.1

[PATCH v3 0/4] mxs-lradc: Split driver into MFD

[Ksenija Stanojevic]

Split existing driver mxs-lradc into MFD with touchscreen and
IIO part.

Tested on i.MX28.

Ksenija Stanojevic (4):
  mfd: mxs-lradc: Add support for mxs-lradc MFD
  iio: adc: mxs-lradc: Add support for adc driver
  input: touchscreen: mxs-lradc: Add support for touchscreen
  iio: adc: mxs-lradc: Remove driver

 drivers/iio/adc/Kconfig                  |   27 +-
 drivers/iio/adc/Makefile                 |    2 +-
 drivers/iio/adc/mxs-lradc-adc.c          |  811 ++++++++++++++
 drivers/iio/adc/mxs-lradc.c              | 1775 ------------------------------
 drivers/input/touchscreen/Kconfig        |   10 +
 drivers/input/touchscreen/Makefile       |    1 +
 drivers/input/touchscreen/mxs-lradc-ts.c |  729 ++++++++++++
 drivers/mfd/Kconfig                      |   17 +
 drivers/mfd/Makefile                     |    1 +
 drivers/mfd/mxs-lradc.c                  |  217 ++++
 include/linux/mfd/mxs-lradc.h            |  204 ++++
 11 files changed, 2004 insertions(+), 1790 deletions(-)
 create mode 100644 drivers/iio/adc/mxs-lradc-adc.c
 delete mode 100644 drivers/iio/adc/mxs-lradc.c
 create mode 100644 drivers/input/touchscreen/mxs-lradc-ts.c
 create mode 100644 drivers/mfd/mxs-lradc.c
 create mode 100644 include/linux/mfd/mxs-lradc.h

-- 
1.9.1

[PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojevic]

Add core files for mxs-lradc MFD driver.

Note:  this patch won't compile in iio/testing without this patch:
a8f447be8056 ("mfd: Add resource managed APIs for mfd_add_devices")

Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Acked-by: Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
---
Changes in v3:
 - add note to commit message
 - move switch statement into if(touch_ret == 0) branch
 - add MODULE_AUTHOR

Changes in v2:
 - do not change spacing in Kconfig
 - make struct mfd_cell part of struct mxs_lradc
 - use switch instead of if in mxs_lradc_irq_mask
 - use only necessary header files in mxs_lradc.h
 - use devm_mfd_add_device
 - use separate function to register mfd device
 - change licence to GPL
 - add copyright

 drivers/mfd/Kconfig           |  17 ++++
 drivers/mfd/Makefile          |   1 +
 drivers/mfd/mxs-lradc.c       | 217 ++++++++++++++++++++++++++++++++++++++++++
 include/linux/mfd/mxs-lradc.h | 204 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 439 insertions(+)
 create mode 100644 drivers/mfd/mxs-lradc.c
 create mode 100644 include/linux/mfd/mxs-lradc.h

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 9ca66de..62593ad 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -271,6 +271,23 @@ config MFD_MC13XXX_I2C
 	help
 	  Select this if your MC13xxx is connected via an I2C bus.
 
+config MFD_MXS_LRADC
+	tristate "Freescale i.MX23/i.MX28 LRADC"
+	depends on ARCH_MXS || COMPILE_TEST
+	select MFD_CORE
+	select STMP_DEVICE
+	help
+	  Say yes here to build support for the low-resolution
+	  analog-to-digital converter (LRADC) found on the i.MX23 and i.MX28
+	  processors. This driver provides common support for accessing the
+	  device, additional drivers must be enabled in order to use the
+	  functionality of the device:
+		mxs-lradc-adc for ADC readings
+		mxs-lradc-ts  for touchscreen support
+
+	  This driver can also be built as a module. If so, the module will be
+	  called mxs-lradc.
+
 config MFD_HI6421_PMIC
 	tristate "HiSilicon Hi6421 PMU/Codec IC"
 	depends on OF
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 0f230a6..ecf6399 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -198,3 +198,4 @@ intel-soc-pmic-objs		:= intel_soc_pmic_core.o intel_soc_pmic_crc.o
 intel-soc-pmic-$(CONFIG_INTEL_PMC_IPC)	+= intel_soc_pmic_bxtwc.o
 obj-$(CONFIG_INTEL_SOC_PMIC)	+= intel-soc-pmic.o
 obj-$(CONFIG_MFD_MT6397)	+= mt6397-core.o
+obj-$(CONFIG_MFD_MXS_LRADC)	+= mxs-lradc.o
diff --git a/drivers/mfd/mxs-lradc.c b/drivers/mfd/mxs-lradc.c
new file mode 100644
index 0000000..d53a524
--- /dev/null
+++ b/drivers/mfd/mxs-lradc.c
@@ -0,0 +1,217 @@
+/*
+ * Freescale MXS LRADC driver
+ *
+ * Copyright (c) 2012 DENX Software Engineering, GmbH.
+ * Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>
+ * Ksenija Stanojevic <ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/mxs-lradc.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+static const char * const mx23_lradc_irq_names[] = {
+	"mxs-lradc-touchscreen",
+	"mxs-lradc-channel0",
+	"mxs-lradc-channel1",
+	"mxs-lradc-channel2",
+	"mxs-lradc-channel3",
+	"mxs-lradc-channel4",
+	"mxs-lradc-channel5",
+	"mxs-lradc-channel6",
+	"mxs-lradc-channel7",
+};
+
+static const char * const mx28_lradc_irq_names[] = {
+	"mxs-lradc-touchscreen",
+	"mxs-lradc-thresh0",
+	"mxs-lradc-thresh1",
+	"mxs-lradc-channel0",
+	"mxs-lradc-channel1",
+	"mxs-lradc-channel2",
+	"mxs-lradc-channel3",
+	"mxs-lradc-channel4",
+	"mxs-lradc-channel5",
+	"mxs-lradc-channel6",
+	"mxs-lradc-channel7",
+	"mxs-lradc-button0",
+	"mxs-lradc-button1",
+};
+
+struct mxs_lradc_of_config {
+	const int		irq_count;
+	const char * const	*irq_name;
+};
+
+static const struct mxs_lradc_of_config mxs_lradc_of_config[] = {
+	[IMX23_LRADC] = {
+		.irq_count	= ARRAY_SIZE(mx23_lradc_irq_names),
+		.irq_name	= mx23_lradc_irq_names,
+	},
+	[IMX28_LRADC] = {
+		.irq_count	= ARRAY_SIZE(mx28_lradc_irq_names),
+		.irq_name	= mx28_lradc_irq_names,
+	},
+};
+
+static const struct of_device_id mxs_lradc_dt_ids[] = {
+	{ .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
+	{ .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
+
+static int mxs_lradc_add_device(struct platform_device *pdev,
+				struct mxs_lradc *lradc, char *name, int i)
+{
+	struct mfd_cell *cell;
+
+	cell = &lradc->cells[i];
+	cell->name = name;
+	cell->platform_data = lradc;
+	cell->pdata_size = sizeof(*lradc);
+
+	return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
+}
+
+static int mxs_lradc_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *of_id =
+		of_match_device(mxs_lradc_dt_ids, &pdev->dev);
+	const struct mxs_lradc_of_config *of_cfg =
+		&mxs_lradc_of_config[(enum mxs_lradc_id)of_id->data];
+	struct device *dev = &pdev->dev;
+	struct device_node *node = dev->of_node;
+	struct mxs_lradc *lradc;
+	struct resource *iores;
+	int ret = 0, touch_ret, i;
+	u32 ts_wires = 0;
+
+	lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
+	if (!lradc)
+		return -ENOMEM;
+	lradc->soc = (enum mxs_lradc_id)of_id->data;
+
+	/* Grab the memory area */
+	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	lradc->base = devm_ioremap_resource(dev, iores);
+	if (IS_ERR(lradc->base))
+		return PTR_ERR(lradc->base);
+
+	lradc->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(lradc->clk)) {
+		dev_err(dev, "Failed to get the delay unit clock\n");
+		return PTR_ERR(lradc->clk);
+	}
+	ret = clk_prepare_enable(lradc->clk);
+	if (ret != 0) {
+		dev_err(dev, "Failed to enable the delay unit clock\n");
+		return ret;
+	}
+
+	touch_ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
+					 &ts_wires);
+
+	if (touch_ret == 0) {
+		lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;
+		switch (ts_wires) {
+		case 4:
+			lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_4WIRE;
+			break;
+		case 5:
+			if (lradc->soc == IMX28_LRADC) {
+				lradc->use_touchscreen =
+					MXS_LRADC_TOUCHSCREEN_5WIRE;
+				break;
+			}
+			/* fall through an error message for i.MX23 */
+		default:
+			dev_err(&pdev->dev,
+				"Unsupported number of touchscreen wires (%d)\n",
+				ts_wires);
+			return -EINVAL;
+		}
+	} else {
+		lradc->buffer_vchans = BUFFER_VCHANS_ALL;
+	}
+
+	lradc->irq_count = of_cfg->irq_count;
+	lradc->irq_name = of_cfg->irq_name;
+	for (i = 0; i < lradc->irq_count; i++) {
+		lradc->irq[i] = platform_get_irq(pdev, i);
+		if (lradc->irq[i] < 0) {
+			ret = lradc->irq[i];
+			goto err_clk;
+		}
+	}
+
+	platform_set_drvdata(pdev, lradc);
+
+	ret = stmp_reset_block(lradc->base);
+	if (ret)
+		return ret;
+
+	ret = mxs_lradc_add_device(pdev, lradc, DRIVER_NAME_ADC, 0);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to add the ADC subdevice\n");
+		goto err_clk;
+	}
+
+	if (!lradc->use_touchscreen)
+		return 0;
+
+	ret = mxs_lradc_add_device(pdev, lradc, DRIVER_NAME_TS, 1);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"Failed to add the touchscreen subdevice\n");
+		goto err_clk;
+	}
+
+	return 0;
+
+err_clk:
+	clk_disable_unprepare(lradc->clk);
+
+	return ret;
+}
+
+static int mxs_lradc_remove(struct platform_device *pdev)
+{
+	struct mxs_lradc *lradc = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(lradc->clk);
+
+	return 0;
+}
+
+static struct platform_driver mxs_lradc_driver = {
+	.driver = {
+		.name = "mxs-lradc",
+		.of_match_table = mxs_lradc_dt_ids,
+	},
+	.probe = mxs_lradc_probe,
+	.remove = mxs_lradc_remove,
+};
+
+module_platform_driver(mxs_lradc_driver);
+
+MODULE_AUTHOR("Ksenija Stanojevic <ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>");
+MODULE_DESCRIPTION("Freescale i.MX23/i.MX28 LRADC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:mxs-lradc");
diff --git a/include/linux/mfd/mxs-lradc.h b/include/linux/mfd/mxs-lradc.h
new file mode 100644
index 0000000..c1475c0
--- /dev/null
+++ b/include/linux/mfd/mxs-lradc.h
@@ -0,0 +1,204 @@
+/*
+ * Freescale MXS LRADC driver
+ *
+ * Copyright (c) 2012 DENX Software Engineering, GmbH.
+ * Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __MXS_LRADC_H
+#define __MXS_LRADC_H
+
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <linux/stmp_device.h>
+
+#define DRIVER_NAME_ADC "mxs-lradc-adc"
+#define DRIVER_NAME_TS "mxs-lradc-ts"
+
+#define LRADC_MAX_DELAY_CHANS	4
+#define LRADC_MAX_MAPPED_CHANS	8
+#define LRADC_MAX_TOTAL_CHANS	16
+
+#define LRADC_DELAY_TIMER_HZ	2000
+
+#define LRADC_CTRL0				0x00
+# define LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE	BIT(23)
+# define LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE	BIT(22)
+# define LRADC_CTRL0_MX28_YNNSW /* YM */	BIT(21)
+# define LRADC_CTRL0_MX28_YPNSW /* YP */	BIT(20)
+# define LRADC_CTRL0_MX28_YPPSW /* YP */	BIT(19)
+# define LRADC_CTRL0_MX28_XNNSW /* XM */	BIT(18)
+# define LRADC_CTRL0_MX28_XNPSW /* XM */	BIT(17)
+# define LRADC_CTRL0_MX28_XPPSW /* XP */	BIT(16)
+
+# define LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE	BIT(20)
+# define LRADC_CTRL0_MX23_YM			BIT(19)
+# define LRADC_CTRL0_MX23_XM			BIT(18)
+# define LRADC_CTRL0_MX23_YP			BIT(17)
+# define LRADC_CTRL0_MX23_XP			BIT(16)
+
+# define LRADC_CTRL0_MX28_PLATE_MASK \
+		(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE | \
+		LRADC_CTRL0_MX28_YNNSW | LRADC_CTRL0_MX28_YPNSW | \
+		LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW | \
+		LRADC_CTRL0_MX28_XNPSW | LRADC_CTRL0_MX28_XPPSW)
+
+# define LRADC_CTRL0_MX23_PLATE_MASK \
+		(LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE | \
+		LRADC_CTRL0_MX23_YM | LRADC_CTRL0_MX23_XM | \
+		LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XP)
+
+#define LRADC_CTRL1				0x10
+#define LRADC_CTRL1_TOUCH_DETECT_IRQ_EN		BIT(24)
+#define LRADC_CTRL1_LRADC_IRQ_EN(n)		(1 << ((n) + 16))
+#define LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK	(0x1fff << 16)
+#define LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK	(0x01ff << 16)
+#define LRADC_CTRL1_LRADC_IRQ_EN_OFFSET		16
+#define LRADC_CTRL1_TOUCH_DETECT_IRQ		BIT(8)
+#define LRADC_CTRL1_LRADC_IRQ(n)		(1 << (n))
+#define LRADC_CTRL1_MX28_LRADC_IRQ_MASK		0x1fff
+#define LRADC_CTRL1_MX23_LRADC_IRQ_MASK		0x01ff
+#define LRADC_CTRL1_LRADC_IRQ_OFFSET		0
+
+#define LRADC_CTRL2				0x20
+#define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET	24
+#define LRADC_CTRL2_TEMPSENSE_PWD		BIT(15)
+
+#define LRADC_STATUS				0x40
+#define LRADC_STATUS_TOUCH_DETECT_RAW		BIT(0)
+
+#define LRADC_CH(n)				(0x50 + (0x10 * (n)))
+#define LRADC_CH_ACCUMULATE			BIT(29)
+#define LRADC_CH_NUM_SAMPLES_MASK		(0x1f << 24)
+#define LRADC_CH_NUM_SAMPLES_OFFSET		24
+#define LRADC_CH_NUM_SAMPLES(x) \
+				((x) << LRADC_CH_NUM_SAMPLES_OFFSET)
+#define LRADC_CH_VALUE_MASK			0x3ffff
+#define LRADC_CH_VALUE_OFFSET			0
+
+#define LRADC_DELAY(n)				(0xd0 + (0x10 * (n)))
+#define LRADC_DELAY_TRIGGER_LRADCS_MASK		(0xffUL << 24)
+#define LRADC_DELAY_TRIGGER_LRADCS_OFFSET	24
+#define LRADC_DELAY_TRIGGER(x) \
+				(((x) << LRADC_DELAY_TRIGGER_LRADCS_OFFSET) & \
+				LRADC_DELAY_TRIGGER_LRADCS_MASK)
+#define LRADC_DELAY_KICK			BIT(20)
+#define LRADC_DELAY_TRIGGER_DELAYS_MASK		(0xf << 16)
+#define LRADC_DELAY_TRIGGER_DELAYS_OFFSET	16
+#define LRADC_DELAY_TRIGGER_DELAYS(x) \
+				(((x) << LRADC_DELAY_TRIGGER_DELAYS_OFFSET) & \
+				LRADC_DELAY_TRIGGER_DELAYS_MASK)
+#define LRADC_DELAY_LOOP_COUNT_MASK		(0x1f << 11)
+#define LRADC_DELAY_LOOP_COUNT_OFFSET		11
+#define LRADC_DELAY_LOOP(x) \
+				(((x) << LRADC_DELAY_LOOP_COUNT_OFFSET) & \
+				LRADC_DELAY_LOOP_COUNT_MASK)
+#define LRADC_DELAY_DELAY_MASK			0x7ff
+#define LRADC_DELAY_DELAY_OFFSET		0
+#define LRADC_DELAY_DELAY(x) \
+				(((x) << LRADC_DELAY_DELAY_OFFSET) & \
+				LRADC_DELAY_DELAY_MASK)
+
+#define LRADC_CTRL4				0x140
+#define LRADC_CTRL4_LRADCSELECT_MASK(n)		(0xf << ((n) * 4))
+#define LRADC_CTRL4_LRADCSELECT_OFFSET(n)	((n) * 4)
+#define LRADC_CTRL4_LRADCSELECT(n, x) \
+				(((x) << LRADC_CTRL4_LRADCSELECT_OFFSET(n)) & \
+				LRADC_CTRL4_LRADCSELECT_MASK(n))
+
+#define LRADC_RESOLUTION			12
+#define LRADC_SINGLE_SAMPLE_MASK		((1 << LRADC_RESOLUTION) - 1)
+
+enum mxs_lradc_id {
+	IMX23_LRADC,
+	IMX28_LRADC,
+};
+
+enum mxs_lradc_ts_wires {
+	MXS_LRADC_TOUCHSCREEN_NONE = 0,
+	MXS_LRADC_TOUCHSCREEN_4WIRE,
+	MXS_LRADC_TOUCHSCREEN_5WIRE,
+};
+
+struct mxs_lradc {
+	enum mxs_lradc_id	soc;
+
+	void __iomem		*base;
+	struct clk		*clk;
+
+	int			irq[13];
+	const char * const	*irq_name;
+	int			irq_count;
+
+#define BUFFER_VCHANS_LIMITED		0x3f
+#define BUFFER_VCHANS_ALL		0xff
+	u8			buffer_vchans;
+
+	/*
+	 * Certain LRADC channels are shared between touchscreen
+	 * and/or touch-buttons and generic LRADC block. Therefore when using
+	 * either of these, these channels are not available for the regular
+	 * sampling. The shared channels are as follows:
+	 *
+	 * CH0 -- Touch button #0
+	 * CH1 -- Touch button #1
+	 * CH2 -- Touch screen XPUL
+	 * CH3 -- Touch screen YPLL
+	 * CH4 -- Touch screen XNUL
+	 * CH5 -- Touch screen YNLR
+	 * CH6 -- Touch screen WIPER (5-wire only)
+	 *
+	 * The bit fields below represents which parts of the LRADC block are
+	 * switched into special mode of operation. These channels can not
+	 * be sampled as regular LRADC channels. The driver will refuse any
+	 * attempt to sample these channels.
+	 */
+#define CHAN_MASK_TOUCHBUTTON		(BIT(1) | BIT(0))
+#define CHAN_MASK_TOUCHSCREEN_4WIRE	(0xf << 2)
+#define CHAN_MASK_TOUCHSCREEN_5WIRE	(0x1f << 2)
+	enum mxs_lradc_ts_wires	use_touchscreen;
+	bool			use_touchbutton;
+
+#define MXS_LRADC_CELLS			2
+	struct mfd_cell cells[MXS_LRADC_CELLS];
+};
+
+static inline void mxs_lradc_reg_set(struct mxs_lradc *lradc, u32 val, u32 reg)
+{
+	writel(val, lradc->base + reg + STMP_OFFSET_REG_SET);
+}
+
+static inline void mxs_lradc_reg_clear(struct mxs_lradc *lradc, u32 val,
+				       u32 reg)
+{
+	writel(val, lradc->base + reg + STMP_OFFSET_REG_CLR);
+}
+
+static inline void mxs_lradc_reg_wrt(struct mxs_lradc *lradc, u32 val, u32 reg)
+{
+	writel(val, lradc->base + reg);
+}
+
+static inline u32 mxs_lradc_irq_mask(struct mxs_lradc *lradc)
+{
+	switch (lradc->soc) {
+	case IMX23_LRADC:
+		return LRADC_CTRL1_MX23_LRADC_IRQ_MASK;
+	case IMX28_LRADC:
+		return LRADC_CTRL1_MX28_LRADC_IRQ_MASK;
+	default:
+		return 0;
+	}
+}
+
+#endif /* __MXS_LRADC_H */
-- 
1.9.1

[PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojevic]

Add core files for mxs-lradc MFD driver.

Note:  this patch won't compile in iio/testing without this patch:
a8f447be8056 ("mfd: Add resource managed APIs for mfd_add_devices")

Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
---
Changes in v3:
 - add note to commit message
 - move switch statement into if(touch_ret == 0) branch
 - add MODULE_AUTHOR

Changes in v2:
 - do not change spacing in Kconfig
 - make struct mfd_cell part of struct mxs_lradc
 - use switch instead of if in mxs_lradc_irq_mask
 - use only necessary header files in mxs_lradc.h
 - use devm_mfd_add_device
 - use separate function to register mfd device
 - change licence to GPL
 - add copyright

 drivers/mfd/Kconfig           |  17 ++++
 drivers/mfd/Makefile          |   1 +
 drivers/mfd/mxs-lradc.c       | 217 ++++++++++++++++++++++++++++++++++++++++++
 include/linux/mfd/mxs-lradc.h | 204 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 439 insertions(+)
 create mode 100644 drivers/mfd/mxs-lradc.c
 create mode 100644 include/linux/mfd/mxs-lradc.h

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 9ca66de..62593ad 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -271,6 +271,23 @@ config MFD_MC13XXX_I2C
 	help
 	  Select this if your MC13xxx is connected via an I2C bus.
 
+config MFD_MXS_LRADC
+	tristate "Freescale i.MX23/i.MX28 LRADC"
+	depends on ARCH_MXS || COMPILE_TEST
+	select MFD_CORE
+	select STMP_DEVICE
+	help
+	  Say yes here to build support for the low-resolution
+	  analog-to-digital converter (LRADC) found on the i.MX23 and i.MX28
+	  processors. This driver provides common support for accessing the
+	  device, additional drivers must be enabled in order to use the
+	  functionality of the device:
+		mxs-lradc-adc for ADC readings
+		mxs-lradc-ts  for touchscreen support
+
+	  This driver can also be built as a module. If so, the module will be
+	  called mxs-lradc.
+
 config MFD_HI6421_PMIC
 	tristate "HiSilicon Hi6421 PMU/Codec IC"
 	depends on OF
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 0f230a6..ecf6399 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -198,3 +198,4 @@ intel-soc-pmic-objs		:= intel_soc_pmic_core.o intel_soc_pmic_crc.o
 intel-soc-pmic-$(CONFIG_INTEL_PMC_IPC)	+= intel_soc_pmic_bxtwc.o
 obj-$(CONFIG_INTEL_SOC_PMIC)	+= intel-soc-pmic.o
 obj-$(CONFIG_MFD_MT6397)	+= mt6397-core.o
+obj-$(CONFIG_MFD_MXS_LRADC)	+= mxs-lradc.o
diff --git a/drivers/mfd/mxs-lradc.c b/drivers/mfd/mxs-lradc.c
new file mode 100644
index 0000000..d53a524
--- /dev/null
+++ b/drivers/mfd/mxs-lradc.c
@@ -0,0 +1,217 @@
+/*
+ * Freescale MXS LRADC driver
+ *
+ * Copyright (c) 2012 DENX Software Engineering, GmbH.
+ * Marek Vasut <marex@denx.de>
+ * Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/mxs-lradc.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+static const char * const mx23_lradc_irq_names[] = {
+	"mxs-lradc-touchscreen",
+	"mxs-lradc-channel0",
+	"mxs-lradc-channel1",
+	"mxs-lradc-channel2",
+	"mxs-lradc-channel3",
+	"mxs-lradc-channel4",
+	"mxs-lradc-channel5",
+	"mxs-lradc-channel6",
+	"mxs-lradc-channel7",
+};
+
+static const char * const mx28_lradc_irq_names[] = {
+	"mxs-lradc-touchscreen",
+	"mxs-lradc-thresh0",
+	"mxs-lradc-thresh1",
+	"mxs-lradc-channel0",
+	"mxs-lradc-channel1",
+	"mxs-lradc-channel2",
+	"mxs-lradc-channel3",
+	"mxs-lradc-channel4",
+	"mxs-lradc-channel5",
+	"mxs-lradc-channel6",
+	"mxs-lradc-channel7",
+	"mxs-lradc-button0",
+	"mxs-lradc-button1",
+};
+
+struct mxs_lradc_of_config {
+	const int		irq_count;
+	const char * const	*irq_name;
+};
+
+static const struct mxs_lradc_of_config mxs_lradc_of_config[] = {
+	[IMX23_LRADC] = {
+		.irq_count	= ARRAY_SIZE(mx23_lradc_irq_names),
+		.irq_name	= mx23_lradc_irq_names,
+	},
+	[IMX28_LRADC] = {
+		.irq_count	= ARRAY_SIZE(mx28_lradc_irq_names),
+		.irq_name	= mx28_lradc_irq_names,
+	},
+};
+
+static const struct of_device_id mxs_lradc_dt_ids[] = {
+	{ .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
+	{ .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
+
+static int mxs_lradc_add_device(struct platform_device *pdev,
+				struct mxs_lradc *lradc, char *name, int i)
+{
+	struct mfd_cell *cell;
+
+	cell = &lradc->cells[i];
+	cell->name = name;
+	cell->platform_data = lradc;
+	cell->pdata_size = sizeof(*lradc);
+
+	return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
+}
+
+static int mxs_lradc_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *of_id =
+		of_match_device(mxs_lradc_dt_ids, &pdev->dev);
+	const struct mxs_lradc_of_config *of_cfg =
+		&mxs_lradc_of_config[(enum mxs_lradc_id)of_id->data];
+	struct device *dev = &pdev->dev;
+	struct device_node *node = dev->of_node;
+	struct mxs_lradc *lradc;
+	struct resource *iores;
+	int ret = 0, touch_ret, i;
+	u32 ts_wires = 0;
+
+	lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
+	if (!lradc)
+		return -ENOMEM;
+	lradc->soc = (enum mxs_lradc_id)of_id->data;
+
+	/* Grab the memory area */
+	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	lradc->base = devm_ioremap_resource(dev, iores);
+	if (IS_ERR(lradc->base))
+		return PTR_ERR(lradc->base);
+
+	lradc->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(lradc->clk)) {
+		dev_err(dev, "Failed to get the delay unit clock\n");
+		return PTR_ERR(lradc->clk);
+	}
+	ret = clk_prepare_enable(lradc->clk);
+	if (ret != 0) {
+		dev_err(dev, "Failed to enable the delay unit clock\n");
+		return ret;
+	}
+
+	touch_ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
+					 &ts_wires);
+
+	if (touch_ret == 0) {
+		lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;
+		switch (ts_wires) {
+		case 4:
+			lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_4WIRE;
+			break;
+		case 5:
+			if (lradc->soc == IMX28_LRADC) {
+				lradc->use_touchscreen =
+					MXS_LRADC_TOUCHSCREEN_5WIRE;
+				break;
+			}
+			/* fall through an error message for i.MX23 */
+		default:
+			dev_err(&pdev->dev,
+				"Unsupported number of touchscreen wires (%d)\n",
+				ts_wires);
+			return -EINVAL;
+		}
+	} else {
+		lradc->buffer_vchans = BUFFER_VCHANS_ALL;
+	}
+
+	lradc->irq_count = of_cfg->irq_count;
+	lradc->irq_name = of_cfg->irq_name;
+	for (i = 0; i < lradc->irq_count; i++) {
+		lradc->irq[i] = platform_get_irq(pdev, i);
+		if (lradc->irq[i] < 0) {
+			ret = lradc->irq[i];
+			goto err_clk;
+		}
+	}
+
+	platform_set_drvdata(pdev, lradc);
+
+	ret = stmp_reset_block(lradc->base);
+	if (ret)
+		return ret;
+
+	ret = mxs_lradc_add_device(pdev, lradc, DRIVER_NAME_ADC, 0);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to add the ADC subdevice\n");
+		goto err_clk;
+	}
+
+	if (!lradc->use_touchscreen)
+		return 0;
+
+	ret = mxs_lradc_add_device(pdev, lradc, DRIVER_NAME_TS, 1);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"Failed to add the touchscreen subdevice\n");
+		goto err_clk;
+	}
+
+	return 0;
+
+err_clk:
+	clk_disable_unprepare(lradc->clk);
+
+	return ret;
+}
+
+static int mxs_lradc_remove(struct platform_device *pdev)
+{
+	struct mxs_lradc *lradc = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(lradc->clk);
+
+	return 0;
+}
+
+static struct platform_driver mxs_lradc_driver = {
+	.driver = {
+		.name = "mxs-lradc",
+		.of_match_table = mxs_lradc_dt_ids,
+	},
+	.probe = mxs_lradc_probe,
+	.remove = mxs_lradc_remove,
+};
+
+module_platform_driver(mxs_lradc_driver);
+
+MODULE_AUTHOR("Ksenija Stanojevic <ksenija.stanojevic@gmail.com>");
+MODULE_DESCRIPTION("Freescale i.MX23/i.MX28 LRADC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:mxs-lradc");
diff --git a/include/linux/mfd/mxs-lradc.h b/include/linux/mfd/mxs-lradc.h
new file mode 100644
index 0000000..c1475c0
--- /dev/null
+++ b/include/linux/mfd/mxs-lradc.h
@@ -0,0 +1,204 @@
+/*
+ * Freescale MXS LRADC driver
+ *
+ * Copyright (c) 2012 DENX Software Engineering, GmbH.
+ * Marek Vasut <marex@denx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __MXS_LRADC_H
+#define __MXS_LRADC_H
+
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <linux/stmp_device.h>
+
+#define DRIVER_NAME_ADC "mxs-lradc-adc"
+#define DRIVER_NAME_TS "mxs-lradc-ts"
+
+#define LRADC_MAX_DELAY_CHANS	4
+#define LRADC_MAX_MAPPED_CHANS	8
+#define LRADC_MAX_TOTAL_CHANS	16
+
+#define LRADC_DELAY_TIMER_HZ	2000
+
+#define LRADC_CTRL0				0x00
+# define LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE	BIT(23)
+# define LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE	BIT(22)
+# define LRADC_CTRL0_MX28_YNNSW /* YM */	BIT(21)
+# define LRADC_CTRL0_MX28_YPNSW /* YP */	BIT(20)
+# define LRADC_CTRL0_MX28_YPPSW /* YP */	BIT(19)
+# define LRADC_CTRL0_MX28_XNNSW /* XM */	BIT(18)
+# define LRADC_CTRL0_MX28_XNPSW /* XM */	BIT(17)
+# define LRADC_CTRL0_MX28_XPPSW /* XP */	BIT(16)
+
+# define LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE	BIT(20)
+# define LRADC_CTRL0_MX23_YM			BIT(19)
+# define LRADC_CTRL0_MX23_XM			BIT(18)
+# define LRADC_CTRL0_MX23_YP			BIT(17)
+# define LRADC_CTRL0_MX23_XP			BIT(16)
+
+# define LRADC_CTRL0_MX28_PLATE_MASK \
+		(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE | \
+		LRADC_CTRL0_MX28_YNNSW | LRADC_CTRL0_MX28_YPNSW | \
+		LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW | \
+		LRADC_CTRL0_MX28_XNPSW | LRADC_CTRL0_MX28_XPPSW)
+
+# define LRADC_CTRL0_MX23_PLATE_MASK \
+		(LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE | \
+		LRADC_CTRL0_MX23_YM | LRADC_CTRL0_MX23_XM | \
+		LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XP)
+
+#define LRADC_CTRL1				0x10
+#define LRADC_CTRL1_TOUCH_DETECT_IRQ_EN		BIT(24)
+#define LRADC_CTRL1_LRADC_IRQ_EN(n)		(1 << ((n) + 16))
+#define LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK	(0x1fff << 16)
+#define LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK	(0x01ff << 16)
+#define LRADC_CTRL1_LRADC_IRQ_EN_OFFSET		16
+#define LRADC_CTRL1_TOUCH_DETECT_IRQ		BIT(8)
+#define LRADC_CTRL1_LRADC_IRQ(n)		(1 << (n))
+#define LRADC_CTRL1_MX28_LRADC_IRQ_MASK		0x1fff
+#define LRADC_CTRL1_MX23_LRADC_IRQ_MASK		0x01ff
+#define LRADC_CTRL1_LRADC_IRQ_OFFSET		0
+
+#define LRADC_CTRL2				0x20
+#define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET	24
+#define LRADC_CTRL2_TEMPSENSE_PWD		BIT(15)
+
+#define LRADC_STATUS				0x40
+#define LRADC_STATUS_TOUCH_DETECT_RAW		BIT(0)
+
+#define LRADC_CH(n)				(0x50 + (0x10 * (n)))
+#define LRADC_CH_ACCUMULATE			BIT(29)
+#define LRADC_CH_NUM_SAMPLES_MASK		(0x1f << 24)
+#define LRADC_CH_NUM_SAMPLES_OFFSET		24
+#define LRADC_CH_NUM_SAMPLES(x) \
+				((x) << LRADC_CH_NUM_SAMPLES_OFFSET)
+#define LRADC_CH_VALUE_MASK			0x3ffff
+#define LRADC_CH_VALUE_OFFSET			0
+
+#define LRADC_DELAY(n)				(0xd0 + (0x10 * (n)))
+#define LRADC_DELAY_TRIGGER_LRADCS_MASK		(0xffUL << 24)
+#define LRADC_DELAY_TRIGGER_LRADCS_OFFSET	24
+#define LRADC_DELAY_TRIGGER(x) \
+				(((x) << LRADC_DELAY_TRIGGER_LRADCS_OFFSET) & \
+				LRADC_DELAY_TRIGGER_LRADCS_MASK)
+#define LRADC_DELAY_KICK			BIT(20)
+#define LRADC_DELAY_TRIGGER_DELAYS_MASK		(0xf << 16)
+#define LRADC_DELAY_TRIGGER_DELAYS_OFFSET	16
+#define LRADC_DELAY_TRIGGER_DELAYS(x) \
+				(((x) << LRADC_DELAY_TRIGGER_DELAYS_OFFSET) & \
+				LRADC_DELAY_TRIGGER_DELAYS_MASK)
+#define LRADC_DELAY_LOOP_COUNT_MASK		(0x1f << 11)
+#define LRADC_DELAY_LOOP_COUNT_OFFSET		11
+#define LRADC_DELAY_LOOP(x) \
+				(((x) << LRADC_DELAY_LOOP_COUNT_OFFSET) & \
+				LRADC_DELAY_LOOP_COUNT_MASK)
+#define LRADC_DELAY_DELAY_MASK			0x7ff
+#define LRADC_DELAY_DELAY_OFFSET		0
+#define LRADC_DELAY_DELAY(x) \
+				(((x) << LRADC_DELAY_DELAY_OFFSET) & \
+				LRADC_DELAY_DELAY_MASK)
+
+#define LRADC_CTRL4				0x140
+#define LRADC_CTRL4_LRADCSELECT_MASK(n)		(0xf << ((n) * 4))
+#define LRADC_CTRL4_LRADCSELECT_OFFSET(n)	((n) * 4)
+#define LRADC_CTRL4_LRADCSELECT(n, x) \
+				(((x) << LRADC_CTRL4_LRADCSELECT_OFFSET(n)) & \
+				LRADC_CTRL4_LRADCSELECT_MASK(n))
+
+#define LRADC_RESOLUTION			12
+#define LRADC_SINGLE_SAMPLE_MASK		((1 << LRADC_RESOLUTION) - 1)
+
+enum mxs_lradc_id {
+	IMX23_LRADC,
+	IMX28_LRADC,
+};
+
+enum mxs_lradc_ts_wires {
+	MXS_LRADC_TOUCHSCREEN_NONE = 0,
+	MXS_LRADC_TOUCHSCREEN_4WIRE,
+	MXS_LRADC_TOUCHSCREEN_5WIRE,
+};
+
+struct mxs_lradc {
+	enum mxs_lradc_id	soc;
+
+	void __iomem		*base;
+	struct clk		*clk;
+
+	int			irq[13];
+	const char * const	*irq_name;
+	int			irq_count;
+
+#define BUFFER_VCHANS_LIMITED		0x3f
+#define BUFFER_VCHANS_ALL		0xff
+	u8			buffer_vchans;
+
+	/*
+	 * Certain LRADC channels are shared between touchscreen
+	 * and/or touch-buttons and generic LRADC block. Therefore when using
+	 * either of these, these channels are not available for the regular
+	 * sampling. The shared channels are as follows:
+	 *
+	 * CH0 -- Touch button #0
+	 * CH1 -- Touch button #1
+	 * CH2 -- Touch screen XPUL
+	 * CH3 -- Touch screen YPLL
+	 * CH4 -- Touch screen XNUL
+	 * CH5 -- Touch screen YNLR
+	 * CH6 -- Touch screen WIPER (5-wire only)
+	 *
+	 * The bit fields below represents which parts of the LRADC block are
+	 * switched into special mode of operation. These channels can not
+	 * be sampled as regular LRADC channels. The driver will refuse any
+	 * attempt to sample these channels.
+	 */
+#define CHAN_MASK_TOUCHBUTTON		(BIT(1) | BIT(0))
+#define CHAN_MASK_TOUCHSCREEN_4WIRE	(0xf << 2)
+#define CHAN_MASK_TOUCHSCREEN_5WIRE	(0x1f << 2)
+	enum mxs_lradc_ts_wires	use_touchscreen;
+	bool			use_touchbutton;
+
+#define MXS_LRADC_CELLS			2
+	struct mfd_cell cells[MXS_LRADC_CELLS];
+};
+
+static inline void mxs_lradc_reg_set(struct mxs_lradc *lradc, u32 val, u32 reg)
+{
+	writel(val, lradc->base + reg + STMP_OFFSET_REG_SET);
+}
+
+static inline void mxs_lradc_reg_clear(struct mxs_lradc *lradc, u32 val,
+				       u32 reg)
+{
+	writel(val, lradc->base + reg + STMP_OFFSET_REG_CLR);
+}
+
+static inline void mxs_lradc_reg_wrt(struct mxs_lradc *lradc, u32 val, u32 reg)
+{
+	writel(val, lradc->base + reg);
+}
+
+static inline u32 mxs_lradc_irq_mask(struct mxs_lradc *lradc)
+{
+	switch (lradc->soc) {
+	case IMX23_LRADC:
+		return LRADC_CTRL1_MX23_LRADC_IRQ_MASK;
+	case IMX28_LRADC:
+		return LRADC_CTRL1_MX28_LRADC_IRQ_MASK;
+	default:
+		return 0;
+	}
+}
+
+#endif /* __MXS_LRADC_H */
-- 
1.9.1

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Stefan Wahren]

Hi,

> Ksenija Stanojevic <ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> hat am 24. Juni 2016 um
> 14:09 geschrieben:
> 
> 
> Add core files for mxs-lradc MFD driver.
> 
> Note:  this patch won't compile in iio/testing without this patch:
> a8f447be8056 ("mfd: Add resource managed APIs for mfd_add_devices")
> 
> Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Acked-by: Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>

i tested it successfully with a i.MX23 board (without touchscreen).

Tested-by: Stefan Wahren <stefan.wahren-eS4NqCHxEME@public.gmane.org>

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Stefan Wahren]

Hi,

> Ksenija Stanojevic <ksenija.stanojevic@gmail.com> hat am 24. Juni 2016 um
> 14:09 geschrieben:
> 
> 
> Add core files for mxs-lradc MFD driver.
> 
> Note:  this patch won't compile in iio/testing without this patch:
> a8f447be8056 ("mfd: Add resource managed APIs for mfd_add_devices")
> 
> Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
> Acked-by: Jonathan Cameron <jic23@kernel.org>

i tested it successfully with a i.MX23 board (without touchscreen).

Tested-by: Stefan Wahren <stefan.wahren@i2se.com>

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Lee Jones]

On Fri, 24 Jun 2016, Ksenija Stanojevic wrote:

> Add core files for mxs-lradc MFD driver.
> 
> Note:  this patch won't compile in iio/testing without this patch:
> a8f447be8056 ("mfd: Add resource managed APIs for mfd_add_devices")
> 
> Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
> Acked-by: Jonathan Cameron <jic23@kernel.org>
> ---
> Changes in v3:
>  - add note to commit message
>  - move switch statement into if(touch_ret == 0) branch
>  - add MODULE_AUTHOR
> 
> Changes in v2:
>  - do not change spacing in Kconfig
>  - make struct mfd_cell part of struct mxs_lradc
>  - use switch instead of if in mxs_lradc_irq_mask
>  - use only necessary header files in mxs_lradc.h
>  - use devm_mfd_add_device
>  - use separate function to register mfd device
>  - change licence to GPL
>  - add copyright
> 
>  drivers/mfd/Kconfig           |  17 ++++
>  drivers/mfd/Makefile          |   1 +
>  drivers/mfd/mxs-lradc.c       | 217 ++++++++++++++++++++++++++++++++++++++++++
>  include/linux/mfd/mxs-lradc.h | 204 +++++++++++++++++++++++++++++++++++++++
>  4 files changed, 439 insertions(+)
>  create mode 100644 drivers/mfd/mxs-lradc.c
>  create mode 100644 include/linux/mfd/mxs-lradc.h
> 
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 9ca66de..62593ad 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -271,6 +271,23 @@ config MFD_MC13XXX_I2C
>  	help
>  	  Select this if your MC13xxx is connected via an I2C bus.
>  
> +config MFD_MXS_LRADC
> +	tristate "Freescale i.MX23/i.MX28 LRADC"
> +	depends on ARCH_MXS || COMPILE_TEST
> +	select MFD_CORE
> +	select STMP_DEVICE
> +	help
> +	  Say yes here to build support for the low-resolution
> +	  analog-to-digital converter (LRADC) found on the i.MX23 and i.MX28

Low Resolution Analogue-to-Digital Converter 

> +	  processors. This driver provides common support for accessing the
> +	  device, additional drivers must be enabled in order to use the
> +	  functionality of the device:
> +		mxs-lradc-adc for ADC readings
> +		mxs-lradc-ts  for touchscreen support
> +
> +	  This driver can also be built as a module. If so, the module will be
> +	  called mxs-lradc.
> +
>  config MFD_HI6421_PMIC
>  	tristate "HiSilicon Hi6421 PMU/Codec IC"
>  	depends on OF
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 0f230a6..ecf6399 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -198,3 +198,4 @@ intel-soc-pmic-objs		:= intel_soc_pmic_core.o intel_soc_pmic_crc.o
>  intel-soc-pmic-$(CONFIG_INTEL_PMC_IPC)	+= intel_soc_pmic_bxtwc.o
>  obj-$(CONFIG_INTEL_SOC_PMIC)	+= intel-soc-pmic.o
>  obj-$(CONFIG_MFD_MT6397)	+= mt6397-core.o
> +obj-$(CONFIG_MFD_MXS_LRADC)	+= mxs-lradc.o
> diff --git a/drivers/mfd/mxs-lradc.c b/drivers/mfd/mxs-lradc.c
> new file mode 100644
> index 0000000..d53a524
> --- /dev/null
> +++ b/drivers/mfd/mxs-lradc.c
> @@ -0,0 +1,217 @@
> +/*
> + * Freescale MXS LRADC driver
> + *
> + * Copyright (c) 2012 DENX Software Engineering, GmbH.


You need to update the copyright.

Authors:

> + * Marek Vasut <marex@denx.de>
> + * Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/device.h>
> +#include <linux/mfd/core.h>
> +#include <linux/mfd/mxs-lradc.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +static const char * const mx23_lradc_irq_names[] = {
> +	"mxs-lradc-touchscreen",
> +	"mxs-lradc-channel0",
> +	"mxs-lradc-channel1",
> +	"mxs-lradc-channel2",
> +	"mxs-lradc-channel3",
> +	"mxs-lradc-channel4",
> +	"mxs-lradc-channel5",
> +	"mxs-lradc-channel6",
> +	"mxs-lradc-channel7",
> +};
> +
> +static const char * const mx28_lradc_irq_names[] = {
> +	"mxs-lradc-touchscreen",
> +	"mxs-lradc-thresh0",
> +	"mxs-lradc-thresh1",
> +	"mxs-lradc-channel0",
> +	"mxs-lradc-channel1",
> +	"mxs-lradc-channel2",
> +	"mxs-lradc-channel3",
> +	"mxs-lradc-channel4",
> +	"mxs-lradc-channel5",
> +	"mxs-lradc-channel6",
> +	"mxs-lradc-channel7",
> +	"mxs-lradc-button0",
> +	"mxs-lradc-button1",
> +};
> +
> +struct mxs_lradc_of_config {
> +	const int		irq_count;
> +	const char * const	*irq_name;
> +};
> +
> +static const struct mxs_lradc_of_config mxs_lradc_of_config[] = {
> +	[IMX23_LRADC] = {
> +		.irq_count	= ARRAY_SIZE(mx23_lradc_irq_names),
> +		.irq_name	= mx23_lradc_irq_names,
> +	},
> +	[IMX28_LRADC] = {
> +		.irq_count	= ARRAY_SIZE(mx28_lradc_irq_names),
> +		.irq_name	= mx28_lradc_irq_names,
> +	},
> +};

Please use DEFINE_RES_IRQ_NAMED() instead.

> +static const struct of_device_id mxs_lradc_dt_ids[] = {
> +	{ .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
> +	{ .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
> +
> +static int mxs_lradc_add_device(struct platform_device *pdev,
> +				struct mxs_lradc *lradc, char *name, int i)
> +{
> +	struct mfd_cell *cell;
> +
> +	cell = &lradc->cells[i];
> +	cell->name = name;
> +	cell->platform_data = lradc;
> +	cell->pdata_size = sizeof(*lradc);
> +
> +	return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
> +}

Please don't roll your own API.

Use 'struct mfd_cell' like everyone else does.

> +static int mxs_lradc_probe(struct platform_device *pdev)
> +{
> +	const struct of_device_id *of_id =
> +		of_match_device(mxs_lradc_dt_ids, &pdev->dev);
> +	const struct mxs_lradc_of_config *of_cfg =
> +		&mxs_lradc_of_config[(enum mxs_lradc_id)of_id->data];

This implementation is wayyyy more complicated than it needs to be.

You've entangled DT probing with the MFD API.

Please use the MFD API properly.

> +	struct device *dev = &pdev->dev;
> +	struct device_node *node = dev->of_node;
> +	struct mxs_lradc *lradc;
> +	struct resource *iores;
> +	int ret = 0, touch_ret, i;
> +	u32 ts_wires = 0;
> +
> +	lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
> +	if (!lradc)
> +		return -ENOMEM;
> +	lradc->soc = (enum mxs_lradc_id)of_id->data;

If you're going to pull the platform ID out like this, please pull the
*_match_* function down, just above this line.  And separate them both
from allocating memory.

> +	/* Grab the memory area */

This comment doesn't add anything.

We know what these calls do, and they don't "grab" anything.

> +	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	lradc->base = devm_ioremap_resource(dev, iores);
> +	if (IS_ERR(lradc->base))
> +		return PTR_ERR(lradc->base);
> +
> +	lradc->clk = devm_clk_get(&pdev->dev, NULL);
> +	if (IS_ERR(lradc->clk)) {
> +		dev_err(dev, "Failed to get the delay unit clock\n");
> +		return PTR_ERR(lradc->clk);
> +	}

'\n' here.  Nice spacing makes code easier to follow.

> +	ret = clk_prepare_enable(lradc->clk);
> +	if (ret != 0) {
> +		dev_err(dev, "Failed to enable the delay unit clock\n");
> +		return ret;
> +	}
> +
> +	touch_ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
> +					 &ts_wires);

Why do you need more than one 'ret' variable?

> +	if (touch_ret == 0) {
> +		lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;

'\n' here  or else we think it's related to the switch().

> +		switch (ts_wires) {
> +		case 4:
> +			lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_4WIRE;

This is not a good name for a variable.  It looks like a bool here,
but you're initialising with a configuration option.

> +			break;
> +		case 5:
> +			if (lradc->soc == IMX28_LRADC) {
> +				lradc->use_touchscreen =
> +					MXS_LRADC_TOUCHSCREEN_5WIRE;
> +				break;
> +			}
> +			/* fall through an error message for i.MX23 */

"to an error"

> +		default:
> +			dev_err(&pdev->dev,
> +				"Unsupported number of touchscreen wires (%d)\n",
> +				ts_wires);
> +			return -EINVAL;

The clock is still enabled.

> +		}
> +	} else {
> +		lradc->buffer_vchans = BUFFER_VCHANS_ALL;
> +	}
> +
> +	lradc->irq_count = of_cfg->irq_count;
> +	lradc->irq_name = of_cfg->irq_name;
> +	for (i = 0; i < lradc->irq_count; i++) {
> +		lradc->irq[i] = platform_get_irq(pdev, i);
> +		if (lradc->irq[i] < 0) {
> +			ret = lradc->irq[i];
> +			goto err_clk;
> +		}
> +	}

You shouldn't be 'get'ing the IRQ here.

Where are you consuming these IRQs?

> +	platform_set_drvdata(pdev, lradc);
> +
> +	ret = stmp_reset_block(lradc->base);
> +	if (ret)
> +		return ret;


The clock is still enabled.


> +	ret = mxs_lradc_add_device(pdev, lradc, DRIVER_NAME_ADC, 0);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to add the ADC subdevice\n");
> +		goto err_clk;
> +	}

Do this using statically defined mfd_cells.

> +	if (!lradc->use_touchscreen)
> +		return 0;
> +
> +	ret = mxs_lradc_add_device(pdev, lradc, DRIVER_NAME_TS, 1);
> +	if (ret) {
> +		dev_err(&pdev->dev,
> +			"Failed to add the touchscreen subdevice\n");
> +		goto err_clk;
> +	}
> +
> +	return 0;
> +
> +err_clk:
> +	clk_disable_unprepare(lradc->clk);
> +
> +	return ret;
> +}
> +
> +static int mxs_lradc_remove(struct platform_device *pdev)
> +{
> +	struct mxs_lradc *lradc = platform_get_drvdata(pdev);
> +
> +	clk_disable_unprepare(lradc->clk);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver mxs_lradc_driver = {
> +	.driver = {
> +		.name = "mxs-lradc",
> +		.of_match_table = mxs_lradc_dt_ids,
> +	},
> +	.probe = mxs_lradc_probe,
> +	.remove = mxs_lradc_remove,
> +};
> +

This line is superfluous.

> +module_platform_driver(mxs_lradc_driver);
> +
> +MODULE_AUTHOR("Ksenija Stanojevic <ksenija.stanojevic@gmail.com>");
> +MODULE_DESCRIPTION("Freescale i.MX23/i.MX28 LRADC driver");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:mxs-lradc");
> diff --git a/include/linux/mfd/mxs-lradc.h b/include/linux/mfd/mxs-lradc.h
> new file mode 100644
> index 0000000..c1475c0
> --- /dev/null
> +++ b/include/linux/mfd/mxs-lradc.h
> @@ -0,0 +1,204 @@
> +/*
> + * Freescale MXS LRADC driver
> + *
> + * Copyright (c) 2012 DENX Software Engineering, GmbH.

You need to update the copyright.

Author:

> + * Marek Vasut <marex@denx.de>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#ifndef __MXS_LRADC_H
> +#define __MXS_LRADC_H

__MFD_MXS_*

> +#include <linux/bitops.h>
> +#include <linux/io.h>
> +#include <linux/stmp_device.h>
> +
> +#define DRIVER_NAME_ADC "mxs-lradc-adc"
> +#define DRIVER_NAME_TS "mxs-lradc-ts"

Don't define these.  Just use the proper names.

> +#define LRADC_MAX_DELAY_CHANS	4
> +#define LRADC_MAX_MAPPED_CHANS	8
> +#define LRADC_MAX_TOTAL_CHANS	16
> +
> +#define LRADC_DELAY_TIMER_HZ	2000
> +
> +#define LRADC_CTRL0				0x00
> +# define LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE	BIT(23)
> +# define LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE	BIT(22)
> +# define LRADC_CTRL0_MX28_YNNSW /* YM */	BIT(21)
> +# define LRADC_CTRL0_MX28_YPNSW /* YP */	BIT(20)
> +# define LRADC_CTRL0_MX28_YPPSW /* YP */	BIT(19)
> +# define LRADC_CTRL0_MX28_XNNSW /* XM */	BIT(18)
> +# define LRADC_CTRL0_MX28_XNPSW /* XM */	BIT(17)
> +# define LRADC_CTRL0_MX28_XPPSW /* XP */	BIT(16)
> +
> +# define LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE	BIT(20)
> +# define LRADC_CTRL0_MX23_YM			BIT(19)
> +# define LRADC_CTRL0_MX23_XM			BIT(18)
> +# define LRADC_CTRL0_MX23_YP			BIT(17)
> +# define LRADC_CTRL0_MX23_XP			BIT(16)
> +
> +# define LRADC_CTRL0_MX28_PLATE_MASK \
> +		(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE | \
> +		LRADC_CTRL0_MX28_YNNSW | LRADC_CTRL0_MX28_YPNSW | \
> +		LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW | \
> +		LRADC_CTRL0_MX28_XNPSW | LRADC_CTRL0_MX28_XPPSW)
> +
> +# define LRADC_CTRL0_MX23_PLATE_MASK \
> +		(LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE | \
> +		LRADC_CTRL0_MX23_YM | LRADC_CTRL0_MX23_XM | \
> +		LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XP)
> +
> +#define LRADC_CTRL1				0x10
> +#define LRADC_CTRL1_TOUCH_DETECT_IRQ_EN		BIT(24)
> +#define LRADC_CTRL1_LRADC_IRQ_EN(n)		(1 << ((n) + 16))
> +#define LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK	(0x1fff << 16)
> +#define LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK	(0x01ff << 16)
> +#define LRADC_CTRL1_LRADC_IRQ_EN_OFFSET		16
> +#define LRADC_CTRL1_TOUCH_DETECT_IRQ		BIT(8)
> +#define LRADC_CTRL1_LRADC_IRQ(n)		(1 << (n))
> +#define LRADC_CTRL1_MX28_LRADC_IRQ_MASK		0x1fff
> +#define LRADC_CTRL1_MX23_LRADC_IRQ_MASK		0x01ff
> +#define LRADC_CTRL1_LRADC_IRQ_OFFSET		0
> +
> +#define LRADC_CTRL2				0x20
> +#define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET	24
> +#define LRADC_CTRL2_TEMPSENSE_PWD		BIT(15)
> +
> +#define LRADC_STATUS				0x40
> +#define LRADC_STATUS_TOUCH_DETECT_RAW		BIT(0)
> +
> +#define LRADC_CH(n)				(0x50 + (0x10 * (n)))
> +#define LRADC_CH_ACCUMULATE			BIT(29)
> +#define LRADC_CH_NUM_SAMPLES_MASK		(0x1f << 24)
> +#define LRADC_CH_NUM_SAMPLES_OFFSET		24
> +#define LRADC_CH_NUM_SAMPLES(x) \
> +				((x) << LRADC_CH_NUM_SAMPLES_OFFSET)
> +#define LRADC_CH_VALUE_MASK			0x3ffff
> +#define LRADC_CH_VALUE_OFFSET			0
> +
> +#define LRADC_DELAY(n)				(0xd0 + (0x10 * (n)))
> +#define LRADC_DELAY_TRIGGER_LRADCS_MASK		(0xffUL << 24)
> +#define LRADC_DELAY_TRIGGER_LRADCS_OFFSET	24
> +#define LRADC_DELAY_TRIGGER(x) \
> +				(((x) << LRADC_DELAY_TRIGGER_LRADCS_OFFSET) & \
> +				LRADC_DELAY_TRIGGER_LRADCS_MASK)
> +#define LRADC_DELAY_KICK			BIT(20)
> +#define LRADC_DELAY_TRIGGER_DELAYS_MASK		(0xf << 16)
> +#define LRADC_DELAY_TRIGGER_DELAYS_OFFSET	16
> +#define LRADC_DELAY_TRIGGER_DELAYS(x) \
> +				(((x) << LRADC_DELAY_TRIGGER_DELAYS_OFFSET) & \
> +				LRADC_DELAY_TRIGGER_DELAYS_MASK)
> +#define LRADC_DELAY_LOOP_COUNT_MASK		(0x1f << 11)
> +#define LRADC_DELAY_LOOP_COUNT_OFFSET		11
> +#define LRADC_DELAY_LOOP(x) \
> +				(((x) << LRADC_DELAY_LOOP_COUNT_OFFSET) & \
> +				LRADC_DELAY_LOOP_COUNT_MASK)
> +#define LRADC_DELAY_DELAY_MASK			0x7ff
> +#define LRADC_DELAY_DELAY_OFFSET		0
> +#define LRADC_DELAY_DELAY(x) \
> +				(((x) << LRADC_DELAY_DELAY_OFFSET) & \
> +				LRADC_DELAY_DELAY_MASK)
> +
> +#define LRADC_CTRL4				0x140
> +#define LRADC_CTRL4_LRADCSELECT_MASK(n)		(0xf << ((n) * 4))
> +#define LRADC_CTRL4_LRADCSELECT_OFFSET(n)	((n) * 4)
> +#define LRADC_CTRL4_LRADCSELECT(n, x) \
> +				(((x) << LRADC_CTRL4_LRADCSELECT_OFFSET(n)) & \
> +				LRADC_CTRL4_LRADCSELECT_MASK(n))
> +
> +#define LRADC_RESOLUTION			12
> +#define LRADC_SINGLE_SAMPLE_MASK		((1 << LRADC_RESOLUTION) - 1)
> +
> +enum mxs_lradc_id {
> +	IMX23_LRADC,
> +	IMX28_LRADC,
> +};
> +
> +enum mxs_lradc_ts_wires {
> +	MXS_LRADC_TOUCHSCREEN_NONE = 0,
> +	MXS_LRADC_TOUCHSCREEN_4WIRE,
> +	MXS_LRADC_TOUCHSCREEN_5WIRE,
> +};
> +
> +struct mxs_lradc {
> +	enum mxs_lradc_id	soc;
> +
> +	void __iomem		*base;
> +	struct clk		*clk;
> +
> +	int			irq[13];
> +	const char * const	*irq_name;
> +	int			irq_count;

I guess you won't be needing these.

> +#define BUFFER_VCHANS_LIMITED		0x3f
> +#define BUFFER_VCHANS_ALL		0xff

Can you remove all these defines from inside the struct definition
please?

> +	u8			buffer_vchans;
> +
> +	/*
> +	 * Certain LRADC channels are shared between touchscreen
> +	 * and/or touch-buttons and generic LRADC block. Therefore when using
> +	 * either of these, these channels are not available for the regular
> +	 * sampling. The shared channels are as follows:
> +	 *
> +	 * CH0 -- Touch button #0
> +	 * CH1 -- Touch button #1
> +	 * CH2 -- Touch screen XPUL
> +	 * CH3 -- Touch screen YPLL
> +	 * CH4 -- Touch screen XNUL
> +	 * CH5 -- Touch screen YNLR
> +	 * CH6 -- Touch screen WIPER (5-wire only)
> +	 *
> +	 * The bit fields below represents which parts of the LRADC block are
> +	 * switched into special mode of operation. These channels can not
> +	 * be sampled as regular LRADC channels. The driver will refuse any
> +	 * attempt to sample these channels.
> +	 */
> +#define CHAN_MASK_TOUCHBUTTON		(BIT(1) | BIT(0))
> +#define CHAN_MASK_TOUCHSCREEN_4WIRE	(0xf << 2)
> +#define CHAN_MASK_TOUCHSCREEN_5WIRE	(0x1f << 2)
> +	enum mxs_lradc_ts_wires	use_touchscreen;
> +	bool			use_touchbutton;
> +
> +#define MXS_LRADC_CELLS			2
> +	struct mfd_cell cells[MXS_LRADC_CELLS];
> +};
> +
> +static inline void mxs_lradc_reg_set(struct mxs_lradc *lradc, u32 val, u32 reg)
> +{
> +	writel(val, lradc->base + reg + STMP_OFFSET_REG_SET);
> +}
> +
> +static inline void mxs_lradc_reg_clear(struct mxs_lradc *lradc, u32 val,
> +				       u32 reg)
> +{
> +	writel(val, lradc->base + reg + STMP_OFFSET_REG_CLR);
> +}
> +
> +static inline void mxs_lradc_reg_wrt(struct mxs_lradc *lradc, u32 val, u32 reg)
> +{
> +	writel(val, lradc->base + reg);
> +}

Why do you need to abstract the well know, accepted writel calls?

> +static inline u32 mxs_lradc_irq_mask(struct mxs_lradc *lradc)
> +{
> +	switch (lradc->soc) {
> +	case IMX23_LRADC:
> +		return LRADC_CTRL1_MX23_LRADC_IRQ_MASK;
> +	case IMX28_LRADC:
> +		return LRADC_CTRL1_MX28_LRADC_IRQ_MASK;
> +	default:
> +		return 0;
> +	}
> +}
> +
> +#endif /* __MXS_LRADC_H */

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojević]

Hi Lee,

Thank you for the review.

On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones@linaro.org> wrote:
> On Fri, 24 Jun 2016, Ksenija Stanojevic wrote:
>
>> Add core files for mxs-lradc MFD driver.
>>
>> Note:  this patch won't compile in iio/testing without this patch:
>> a8f447be8056 ("mfd: Add resource managed APIs for mfd_add_devices")
>>
>> Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
>> Acked-by: Jonathan Cameron <jic23@kernel.org>
>> ---
>> Changes in v3:
>>  - add note to commit message
>>  - move switch statement into if(touch_ret == 0) branch
>>  - add MODULE_AUTHOR
>>
>> Changes in v2:
>>  - do not change spacing in Kconfig
>>  - make struct mfd_cell part of struct mxs_lradc
>>  - use switch instead of if in mxs_lradc_irq_mask
>>  - use only necessary header files in mxs_lradc.h
>>  - use devm_mfd_add_device
>>  - use separate function to register mfd device
>>  - change licence to GPL
>>  - add copyright
>>
>>  drivers/mfd/Kconfig           |  17 ++++
>>  drivers/mfd/Makefile          |   1 +
>>  drivers/mfd/mxs-lradc.c       | 217 ++++++++++++++++++++++++++++++++++++++++++
>>  include/linux/mfd/mxs-lradc.h | 204 +++++++++++++++++++++++++++++++++++++++
>>  4 files changed, 439 insertions(+)
>>  create mode 100644 drivers/mfd/mxs-lradc.c
>>  create mode 100644 include/linux/mfd/mxs-lradc.h
>>
>> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
>> index 9ca66de..62593ad 100644
>> --- a/drivers/mfd/Kconfig
>> +++ b/drivers/mfd/Kconfig
>> @@ -271,6 +271,23 @@ config MFD_MC13XXX_I2C
>>       help
>>         Select this if your MC13xxx is connected via an I2C bus.
>>
>> +config MFD_MXS_LRADC
>> +     tristate "Freescale i.MX23/i.MX28 LRADC"
>> +     depends on ARCH_MXS || COMPILE_TEST
>> +     select MFD_CORE
>> +     select STMP_DEVICE
>> +     help
>> +       Say yes here to build support for the low-resolution
>> +       analog-to-digital converter (LRADC) found on the i.MX23 and i.MX28
>
> Low Resolution Analogue-to-Digital Converter
>
>> +       processors. This driver provides common support for accessing the
>> +       device, additional drivers must be enabled in order to use the
>> +       functionality of the device:
>> +             mxs-lradc-adc for ADC readings
>> +             mxs-lradc-ts  for touchscreen support
>> +
>> +       This driver can also be built as a module. If so, the module will be
>> +       called mxs-lradc.
>> +
>>  config MFD_HI6421_PMIC
>>       tristate "HiSilicon Hi6421 PMU/Codec IC"
>>       depends on OF
>> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
>> index 0f230a6..ecf6399 100644
>> --- a/drivers/mfd/Makefile
>> +++ b/drivers/mfd/Makefile
>> @@ -198,3 +198,4 @@ intel-soc-pmic-objs               := intel_soc_pmic_core.o intel_soc_pmic_crc.o
>>  intel-soc-pmic-$(CONFIG_INTEL_PMC_IPC)       += intel_soc_pmic_bxtwc.o
>>  obj-$(CONFIG_INTEL_SOC_PMIC) += intel-soc-pmic.o
>>  obj-$(CONFIG_MFD_MT6397)     += mt6397-core.o
>> +obj-$(CONFIG_MFD_MXS_LRADC)  += mxs-lradc.o
>> diff --git a/drivers/mfd/mxs-lradc.c b/drivers/mfd/mxs-lradc.c
>> new file mode 100644
>> index 0000000..d53a524
>> --- /dev/null
>> +++ b/drivers/mfd/mxs-lradc.c
>> @@ -0,0 +1,217 @@
>> +/*
>> + * Freescale MXS LRADC driver
>> + *
>> + * Copyright (c) 2012 DENX Software Engineering, GmbH.
>
>
> You need to update the copyright.
>
> Authors:
>
>> + * Marek Vasut <marex@denx.de>
>> + * Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation; either version 2 of the License, or
>> + * (at your option) any later version.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> + * GNU General Public License for more details.
>> + */
>> +
>> +#include <linux/clk.h>
>> +#include <linux/device.h>
>> +#include <linux/mfd/core.h>
>> +#include <linux/mfd/mxs-lradc.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_device.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/slab.h>
>> +
>> +static const char * const mx23_lradc_irq_names[] = {
>> +     "mxs-lradc-touchscreen",
>> +     "mxs-lradc-channel0",
>> +     "mxs-lradc-channel1",
>> +     "mxs-lradc-channel2",
>> +     "mxs-lradc-channel3",
>> +     "mxs-lradc-channel4",
>> +     "mxs-lradc-channel5",
>> +     "mxs-lradc-channel6",
>> +     "mxs-lradc-channel7",
>> +};
>> +
>> +static const char * const mx28_lradc_irq_names[] = {
>> +     "mxs-lradc-touchscreen",
>> +     "mxs-lradc-thresh0",
>> +     "mxs-lradc-thresh1",
>> +     "mxs-lradc-channel0",
>> +     "mxs-lradc-channel1",
>> +     "mxs-lradc-channel2",
>> +     "mxs-lradc-channel3",
>> +     "mxs-lradc-channel4",
>> +     "mxs-lradc-channel5",
>> +     "mxs-lradc-channel6",
>> +     "mxs-lradc-channel7",
>> +     "mxs-lradc-button0",
>> +     "mxs-lradc-button1",
>> +};
>> +
>> +struct mxs_lradc_of_config {
>> +     const int               irq_count;
>> +     const char * const      *irq_name;
>> +};
>> +
>> +static const struct mxs_lradc_of_config mxs_lradc_of_config[] = {
>> +     [IMX23_LRADC] = {
>> +             .irq_count      = ARRAY_SIZE(mx23_lradc_irq_names),
>> +             .irq_name       = mx23_lradc_irq_names,
>> +     },
>> +     [IMX28_LRADC] = {
>> +             .irq_count      = ARRAY_SIZE(mx28_lradc_irq_names),
>> +             .irq_name       = mx28_lradc_irq_names,
>> +     },
>> +};
>
> Please use DEFINE_RES_IRQ_NAMED() instead.
>
>> +static const struct of_device_id mxs_lradc_dt_ids[] = {
>> +     { .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
>> +     { .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
>> +     { /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
>> +
>> +static int mxs_lradc_add_device(struct platform_device *pdev,
>> +                             struct mxs_lradc *lradc, char *name, int i)
>> +{
>> +     struct mfd_cell *cell;
>> +
>> +     cell = &lradc->cells[i];
>> +     cell->name = name;
>> +     cell->platform_data = lradc;
>> +     cell->pdata_size = sizeof(*lradc);
>> +
>> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
>> +}
>
> Please don't roll your own API.
>
> Use 'struct mfd_cell' like everyone else does.

It has been suggested in previous reviews to use separate function to
register mfd device, and to make mfd_cell allocate dynamically because
struc mxs-lradc is allocated dynamically.
But I can revrse changes and make mfd_cells allocate staticaly
wthout separate function.

>> +static int mxs_lradc_probe(struct platform_device *pdev)
>> +{
>> +     const struct of_device_id *of_id =
>> +             of_match_device(mxs_lradc_dt_ids, &pdev->dev);
>> +     const struct mxs_lradc_of_config *of_cfg =
>> +             &mxs_lradc_of_config[(enum mxs_lradc_id)of_id->data];
>
> This implementation is wayyyy more complicated than it needs to be.
>
> You've entangled DT probing with the MFD API.
>
> Please use the MFD API properly.
>
>> +     struct device *dev = &pdev->dev;
>> +     struct device_node *node = dev->of_node;
>> +     struct mxs_lradc *lradc;
>> +     struct resource *iores;
>> +     int ret = 0, touch_ret, i;
>> +     u32 ts_wires = 0;
>> +
>> +     lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
>> +     if (!lradc)
>> +             return -ENOMEM;
>> +     lradc->soc = (enum mxs_lradc_id)of_id->data;
>
> If you're going to pull the platform ID out like this, please pull the
> *_match_* function down, just above this line.  And separate them both
> from allocating memory.

Ok, but then I will also need to pull this line also:
const struct mxs_lradc_of_config *of_cfg =
 &mxs_lradc_of_config[(enum mxs_lradc_id)of_id->data];

>> +     /* Grab the memory area */
>
> This comment doesn't add anything.

Ok, I will remove it.

> We know what these calls do, and they don't "grab" anything.
>
>> +     iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +     lradc->base = devm_ioremap_resource(dev, iores);
>> +     if (IS_ERR(lradc->base))
>> +             return PTR_ERR(lradc->base);
>> +
>> +     lradc->clk = devm_clk_get(&pdev->dev, NULL);
>> +     if (IS_ERR(lradc->clk)) {
>> +             dev_err(dev, "Failed to get the delay unit clock\n");
>> +             return PTR_ERR(lradc->clk);
>> +     }
>
> '\n' here.  Nice spacing makes code easier to follow.
>
>> +     ret = clk_prepare_enable(lradc->clk);
>> +     if (ret != 0) {
>> +             dev_err(dev, "Failed to enable the delay unit clock\n");
>> +             return ret;
>> +     }
>> +
>> +     touch_ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
>> +                                      &ts_wires);
>
> Why do you need more than one 'ret' variable?

Yeah, it's not really needed.

>> +     if (touch_ret == 0) {
>> +             lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;
>
> '\n' here  or else we think it's related to the switch().
>
>> +             switch (ts_wires) {
>> +             case 4:
>> +                     lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_4WIRE;
>
> This is not a good name for a variable.  It looks like a bool here,
> but you're initialising with a configuration option.

Ok, will touchscreen_wire be ok?

>> +                     break;
>> +             case 5:
>> +                     if (lradc->soc == IMX28_LRADC) {
>> +                             lradc->use_touchscreen =
>> +                                     MXS_LRADC_TOUCHSCREEN_5WIRE;
>> +                             break;
>> +                     }
>> +                     /* fall through an error message for i.MX23 */
>
> "to an error"
>
>> +             default:
>> +                     dev_err(&pdev->dev,
>> +                             "Unsupported number of touchscreen wires (%d)\n",
>> +                             ts_wires);
>> +                     return -EINVAL;
>
> The clock is still enabled.

Ok, I will use goto err_clk

>> +             }
>> +     } else {
>> +             lradc->buffer_vchans = BUFFER_VCHANS_ALL;
>> +     }
>> +
>> +     lradc->irq_count = of_cfg->irq_count;
>> +     lradc->irq_name = of_cfg->irq_name;
>> +     for (i = 0; i < lradc->irq_count; i++) {
>> +             lradc->irq[i] = platform_get_irq(pdev, i);
>> +             if (lradc->irq[i] < 0) {
>> +                     ret = lradc->irq[i];
>> +                     goto err_clk;
>> +             }
>> +     }
>
> You shouldn't be 'get'ing the IRQ here.
>
> Where are you consuming these IRQs?

There are used in adc (mxs-lradc-adc) and touchscreen (mxs-lradc-ts) part.

>> +     platform_set_drvdata(pdev, lradc);
>> +
>> +     ret = stmp_reset_block(lradc->base);
>> +     if (ret)
>> +             return ret;
>
>
> The clock is still enabled.
>
Ok, I will use goto err_clk

>> +     ret = mxs_lradc_add_device(pdev, lradc, DRIVER_NAME_ADC, 0);
>> +     if (ret) {
>> +             dev_err(&pdev->dev, "Failed to add the ADC subdevice\n");
>> +             goto err_clk;
>> +     }
>
> Do this using statically defined mfd_cells.
>
>> +     if (!lradc->use_touchscreen)
>> +             return 0;
>> +
>> +     ret = mxs_lradc_add_device(pdev, lradc, DRIVER_NAME_TS, 1);
>> +     if (ret) {
>> +             dev_err(&pdev->dev,
>> +                     "Failed to add the touchscreen subdevice\n");
>> +             goto err_clk;
>> +     }
>> +
>> +     return 0;
>> +
>> +err_clk:
>> +     clk_disable_unprepare(lradc->clk);
>> +
>> +     return ret;
>> +}
>> +
>> +static int mxs_lradc_remove(struct platform_device *pdev)
>> +{
>> +     struct mxs_lradc *lradc = platform_get_drvdata(pdev);
>> +
>> +     clk_disable_unprepare(lradc->clk);
>> +
>> +     return 0;
>> +}
>> +
>> +static struct platform_driver mxs_lradc_driver = {
>> +     .driver = {
>> +             .name = "mxs-lradc",
>> +             .of_match_table = mxs_lradc_dt_ids,
>> +     },
>> +     .probe = mxs_lradc_probe,
>> +     .remove = mxs_lradc_remove,
>> +};
>> +
>
> This line is superfluous.
>
>> +module_platform_driver(mxs_lradc_driver);
>> +
>> +MODULE_AUTHOR("Ksenija Stanojevic <ksenija.stanojevic@gmail.com>");
>> +MODULE_DESCRIPTION("Freescale i.MX23/i.MX28 LRADC driver");
>> +MODULE_LICENSE("GPL");
>> +MODULE_ALIAS("platform:mxs-lradc");
>> diff --git a/include/linux/mfd/mxs-lradc.h b/include/linux/mfd/mxs-lradc.h
>> new file mode 100644
>> index 0000000..c1475c0
>> --- /dev/null
>> +++ b/include/linux/mfd/mxs-lradc.h
>> @@ -0,0 +1,204 @@
>> +/*
>> + * Freescale MXS LRADC driver
>> + *
>> + * Copyright (c) 2012 DENX Software Engineering, GmbH.
>
> You need to update the copyright.
>
> Author:
>
>> + * Marek Vasut <marex@denx.de>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License as published by
>> + * the Free Software Foundation; either version 2 of the License, or
>> + * (at your option) any later version.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> + * GNU General Public License for more details.
>> + */
>> +
>> +#ifndef __MXS_LRADC_H
>> +#define __MXS_LRADC_H
>
> __MFD_MXS_*
>
>> +#include <linux/bitops.h>
>> +#include <linux/io.h>
>> +#include <linux/stmp_device.h>
>> +
>> +#define DRIVER_NAME_ADC "mxs-lradc-adc"
>> +#define DRIVER_NAME_TS "mxs-lradc-ts"
>
> Don't define these.  Just use the proper names.

Ok.

>> +#define LRADC_MAX_DELAY_CHANS        4
>> +#define LRADC_MAX_MAPPED_CHANS       8
>> +#define LRADC_MAX_TOTAL_CHANS        16
>> +
>> +#define LRADC_DELAY_TIMER_HZ 2000
>> +
>> +#define LRADC_CTRL0                          0x00
>> +# define LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE        BIT(23)
>> +# define LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE  BIT(22)
>> +# define LRADC_CTRL0_MX28_YNNSW /* YM */     BIT(21)
>> +# define LRADC_CTRL0_MX28_YPNSW /* YP */     BIT(20)
>> +# define LRADC_CTRL0_MX28_YPPSW /* YP */     BIT(19)
>> +# define LRADC_CTRL0_MX28_XNNSW /* XM */     BIT(18)
>> +# define LRADC_CTRL0_MX28_XNPSW /* XM */     BIT(17)
>> +# define LRADC_CTRL0_MX28_XPPSW /* XP */     BIT(16)
>> +
>> +# define LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE        BIT(20)
>> +# define LRADC_CTRL0_MX23_YM                 BIT(19)
>> +# define LRADC_CTRL0_MX23_XM                 BIT(18)
>> +# define LRADC_CTRL0_MX23_YP                 BIT(17)
>> +# define LRADC_CTRL0_MX23_XP                 BIT(16)
>> +
>> +# define LRADC_CTRL0_MX28_PLATE_MASK \
>> +             (LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE | \
>> +             LRADC_CTRL0_MX28_YNNSW | LRADC_CTRL0_MX28_YPNSW | \
>> +             LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW | \
>> +             LRADC_CTRL0_MX28_XNPSW | LRADC_CTRL0_MX28_XPPSW)
>> +
>> +# define LRADC_CTRL0_MX23_PLATE_MASK \
>> +             (LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE | \
>> +             LRADC_CTRL0_MX23_YM | LRADC_CTRL0_MX23_XM | \
>> +             LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XP)
>> +
>> +#define LRADC_CTRL1                          0x10
>> +#define LRADC_CTRL1_TOUCH_DETECT_IRQ_EN              BIT(24)
>> +#define LRADC_CTRL1_LRADC_IRQ_EN(n)          (1 << ((n) + 16))
>> +#define LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK   (0x1fff << 16)
>> +#define LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK   (0x01ff << 16)
>> +#define LRADC_CTRL1_LRADC_IRQ_EN_OFFSET              16
>> +#define LRADC_CTRL1_TOUCH_DETECT_IRQ         BIT(8)
>> +#define LRADC_CTRL1_LRADC_IRQ(n)             (1 << (n))
>> +#define LRADC_CTRL1_MX28_LRADC_IRQ_MASK              0x1fff
>> +#define LRADC_CTRL1_MX23_LRADC_IRQ_MASK              0x01ff
>> +#define LRADC_CTRL1_LRADC_IRQ_OFFSET         0
>> +
>> +#define LRADC_CTRL2                          0x20
>> +#define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET     24
>> +#define LRADC_CTRL2_TEMPSENSE_PWD            BIT(15)
>> +
>> +#define LRADC_STATUS                         0x40
>> +#define LRADC_STATUS_TOUCH_DETECT_RAW                BIT(0)
>> +
>> +#define LRADC_CH(n)                          (0x50 + (0x10 * (n)))
>> +#define LRADC_CH_ACCUMULATE                  BIT(29)
>> +#define LRADC_CH_NUM_SAMPLES_MASK            (0x1f << 24)
>> +#define LRADC_CH_NUM_SAMPLES_OFFSET          24
>> +#define LRADC_CH_NUM_SAMPLES(x) \
>> +                             ((x) << LRADC_CH_NUM_SAMPLES_OFFSET)
>> +#define LRADC_CH_VALUE_MASK                  0x3ffff
>> +#define LRADC_CH_VALUE_OFFSET                        0
>> +
>> +#define LRADC_DELAY(n)                               (0xd0 + (0x10 * (n)))
>> +#define LRADC_DELAY_TRIGGER_LRADCS_MASK              (0xffUL << 24)
>> +#define LRADC_DELAY_TRIGGER_LRADCS_OFFSET    24
>> +#define LRADC_DELAY_TRIGGER(x) \
>> +                             (((x) << LRADC_DELAY_TRIGGER_LRADCS_OFFSET) & \
>> +                             LRADC_DELAY_TRIGGER_LRADCS_MASK)
>> +#define LRADC_DELAY_KICK                     BIT(20)
>> +#define LRADC_DELAY_TRIGGER_DELAYS_MASK              (0xf << 16)
>> +#define LRADC_DELAY_TRIGGER_DELAYS_OFFSET    16
>> +#define LRADC_DELAY_TRIGGER_DELAYS(x) \
>> +                             (((x) << LRADC_DELAY_TRIGGER_DELAYS_OFFSET) & \
>> +                             LRADC_DELAY_TRIGGER_DELAYS_MASK)
>> +#define LRADC_DELAY_LOOP_COUNT_MASK          (0x1f << 11)
>> +#define LRADC_DELAY_LOOP_COUNT_OFFSET                11
>> +#define LRADC_DELAY_LOOP(x) \
>> +                             (((x) << LRADC_DELAY_LOOP_COUNT_OFFSET) & \
>> +                             LRADC_DELAY_LOOP_COUNT_MASK)
>> +#define LRADC_DELAY_DELAY_MASK                       0x7ff
>> +#define LRADC_DELAY_DELAY_OFFSET             0
>> +#define LRADC_DELAY_DELAY(x) \
>> +                             (((x) << LRADC_DELAY_DELAY_OFFSET) & \
>> +                             LRADC_DELAY_DELAY_MASK)
>> +
>> +#define LRADC_CTRL4                          0x140
>> +#define LRADC_CTRL4_LRADCSELECT_MASK(n)              (0xf << ((n) * 4))
>> +#define LRADC_CTRL4_LRADCSELECT_OFFSET(n)    ((n) * 4)
>> +#define LRADC_CTRL4_LRADCSELECT(n, x) \
>> +                             (((x) << LRADC_CTRL4_LRADCSELECT_OFFSET(n)) & \
>> +                             LRADC_CTRL4_LRADCSELECT_MASK(n))
>> +
>> +#define LRADC_RESOLUTION                     12
>> +#define LRADC_SINGLE_SAMPLE_MASK             ((1 << LRADC_RESOLUTION) - 1)
>> +
>> +enum mxs_lradc_id {
>> +     IMX23_LRADC,
>> +     IMX28_LRADC,
>> +};
>> +
>> +enum mxs_lradc_ts_wires {
>> +     MXS_LRADC_TOUCHSCREEN_NONE = 0,
>> +     MXS_LRADC_TOUCHSCREEN_4WIRE,
>> +     MXS_LRADC_TOUCHSCREEN_5WIRE,
>> +};
>> +
>> +struct mxs_lradc {
>> +     enum mxs_lradc_id       soc;
>> +
>> +     void __iomem            *base;
>> +     struct clk              *clk;
>> +
>> +     int                     irq[13];
>> +     const char * const      *irq_name;
>> +     int                     irq_count;
>
> I guess you won't be needing these.
>
>> +#define BUFFER_VCHANS_LIMITED                0x3f
>> +#define BUFFER_VCHANS_ALL            0xff
>
> Can you remove all these defines from inside the struct definition
> please?

Ok.

>> +     u8                      buffer_vchans;
>> +
>> +     /*
>> +      * Certain LRADC channels are shared between touchscreen
>> +      * and/or touch-buttons and generic LRADC block. Therefore when using
>> +      * either of these, these channels are not available for the regular
>> +      * sampling. The shared channels are as follows:
>> +      *
>> +      * CH0 -- Touch button #0
>> +      * CH1 -- Touch button #1
>> +      * CH2 -- Touch screen XPUL
>> +      * CH3 -- Touch screen YPLL
>> +      * CH4 -- Touch screen XNUL
>> +      * CH5 -- Touch screen YNLR
>> +      * CH6 -- Touch screen WIPER (5-wire only)
>> +      *
>> +      * The bit fields below represents which parts of the LRADC block are
>> +      * switched into special mode of operation. These channels can not
>> +      * be sampled as regular LRADC channels. The driver will refuse any
>> +      * attempt to sample these channels.
>> +      */
>> +#define CHAN_MASK_TOUCHBUTTON                (BIT(1) | BIT(0))
>> +#define CHAN_MASK_TOUCHSCREEN_4WIRE  (0xf << 2)
>> +#define CHAN_MASK_TOUCHSCREEN_5WIRE  (0x1f << 2)
>> +     enum mxs_lradc_ts_wires use_touchscreen;
>> +     bool                    use_touchbutton;
>> +
>> +#define MXS_LRADC_CELLS                      2
>> +     struct mfd_cell cells[MXS_LRADC_CELLS];
>> +};
>> +
>> +static inline void mxs_lradc_reg_set(struct mxs_lradc *lradc, u32 val, u32 reg)
>> +{
>> +     writel(val, lradc->base + reg + STMP_OFFSET_REG_SET);
>> +}
>> +
>> +static inline void mxs_lradc_reg_clear(struct mxs_lradc *lradc, u32 val,
>> +                                    u32 reg)
>> +{
>> +     writel(val, lradc->base + reg + STMP_OFFSET_REG_CLR);
>> +}
>> +
>> +static inline void mxs_lradc_reg_wrt(struct mxs_lradc *lradc, u32 val, u32 reg)
>> +{
>> +     writel(val, lradc->base + reg);
>> +}
>
> Why do you need to abstract the well know, accepted writel calls?

It makes code more readable.

>> +static inline u32 mxs_lradc_irq_mask(struct mxs_lradc *lradc)
>> +{
>> +     switch (lradc->soc) {
>> +     case IMX23_LRADC:
>> +             return LRADC_CTRL1_MX23_LRADC_IRQ_MASK;
>> +     case IMX28_LRADC:
>> +             return LRADC_CTRL1_MX28_LRADC_IRQ_MASK;
>> +     default:
>> +             return 0;
>> +     }
>> +}
>> +
>> +#endif /* __MXS_LRADC_H */

Regards,
Ksenija

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Harald Geyer]

Hi Ksenija!

Ksenija Stanojević writes:
> On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones@linaro.org> wrote:
> >> +static int mxs_lradc_add_device(struct platform_device *pdev,
> >> +                             struct mxs_lradc *lradc, char *name, int i)
> >> +{
> >> +     struct mfd_cell *cell;
> >> +
> >> +     cell = &lradc->cells[i];
> >> +     cell->name = name;
> >> +     cell->platform_data = lradc;
> >> +     cell->pdata_size = sizeof(*lradc);
> >> +
> >> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
> >> +}
> >
> > Please don't roll your own API.
> >
> > Use 'struct mfd_cell' like everyone else does.
> 
> It has been suggested in previous reviews to use separate function to
> register mfd device, and to make mfd_cell allocate dynamically because
> struc mxs-lradc is allocated dynamically.
> But I can revrse changes and make mfd_cells allocate staticaly
> wthout separate function.

I think making mfd_cells members of struct mxs-lradc will address all
review comments.

HTH,
Harald

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Harald Geyer]

Hi Ksenija!

Ksenija Stanojevi=C4=87 writes:
> On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones@linaro.org> wrote:
> >> +static int mxs_lradc_add_device(struct platform_device *pdev,
> >> +                             struct mxs_lradc *lradc, char *name, in=
t i)
> >> +{
> >> +     struct mfd_cell *cell;
> >> +
> >> +     cell =3D &lradc->cells[i];
> >> +     cell->name =3D name;
> >> +     cell->platform_data =3D lradc;
> >> +     cell->pdata_size =3D sizeof(*lradc);
> >> +
> >> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, N=
ULL);
> >> +}
> >
> > Please don't roll your own API.
> >
> > Use 'struct mfd_cell' like everyone else does.
> =

> It has been suggested in previous reviews to use separate function to
> register mfd device, and to make mfd_cell allocate dynamically because
> struc mxs-lradc is allocated dynamically.
> But I can revrse changes and make mfd_cells allocate staticaly
> wthout separate function.

I think making mfd_cells members of struct mxs-lradc will address all
review comments.

HTH,
Harald

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Lee Jones]

On Fri, 01 Jul 2016, Harald Geyer wrote:

> Hi Ksenija!
> 
> Ksenija Stanojević writes:
> > On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> wrote:
> > >> +static int mxs_lradc_add_device(struct platform_device *pdev,
> > >> +                             struct mxs_lradc *lradc, char *name, int i)
> > >> +{
> > >> +     struct mfd_cell *cell;
> > >> +
> > >> +     cell = &lradc->cells[i];
> > >> +     cell->name = name;
> > >> +     cell->platform_data = lradc;
> > >> +     cell->pdata_size = sizeof(*lradc);
> > >> +
> > >> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
> > >> +}
> > >
> > > Please don't roll your own API.
> > >
> > > Use 'struct mfd_cell' like everyone else does.
> > 
> > It has been suggested in previous reviews to use separate function to
> > register mfd device, and to make mfd_cell allocate dynamically because
> > struc mxs-lradc is allocated dynamically.
> > But I can revrse changes and make mfd_cells allocate staticaly
> > wthout separate function.
> 
> I think making mfd_cells members of struct mxs-lradc will address all
> review comments.

No, please don't do that either.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Lee Jones]

On Fri, 01 Jul 2016, Harald Geyer wrote:

> Hi Ksenija!
> 
> Ksenija Stanojević writes:
> > On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones@linaro.org> wrote:
> > >> +static int mxs_lradc_add_device(struct platform_device *pdev,
> > >> +                             struct mxs_lradc *lradc, char *name, int i)
> > >> +{
> > >> +     struct mfd_cell *cell;
> > >> +
> > >> +     cell = &lradc->cells[i];
> > >> +     cell->name = name;
> > >> +     cell->platform_data = lradc;
> > >> +     cell->pdata_size = sizeof(*lradc);
> > >> +
> > >> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
> > >> +}
> > >
> > > Please don't roll your own API.
> > >
> > > Use 'struct mfd_cell' like everyone else does.
> > 
> > It has been suggested in previous reviews to use separate function to
> > register mfd device, and to make mfd_cell allocate dynamically because
> > struc mxs-lradc is allocated dynamically.
> > But I can revrse changes and make mfd_cells allocate staticaly
> > wthout separate function.
> 
> I think making mfd_cells members of struct mxs-lradc will address all
> review comments.

No, please don't do that either.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Marek Vasut]

On 07/13/2016 02:49 PM, Lee Jones wrote:
> On Fri, 01 Jul 2016, Harald Geyer wrote:
>
>> Hi Ksenija!
>>
>> Ksenija Stanojević writes:
>>> On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> wrote:
>>>>> +static int mxs_lradc_add_device(struct platform_device *pdev,
>>>>> +                             struct mxs_lradc *lradc, char *name, int i)
>>>>> +{
>>>>> +     struct mfd_cell *cell;
>>>>> +
>>>>> +     cell = &lradc->cells[i];
>>>>> +     cell->name = name;
>>>>> +     cell->platform_data = lradc;
>>>>> +     cell->pdata_size = sizeof(*lradc);
>>>>> +
>>>>> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
>>>>> +}
>>>>
>>>> Please don't roll your own API.
>>>>
>>>> Use 'struct mfd_cell' like everyone else does.
>>>
>>> It has been suggested in previous reviews to use separate function to
>>> register mfd device, and to make mfd_cell allocate dynamically because
>>> struc mxs-lradc is allocated dynamically.
>>> But I can revrse changes and make mfd_cells allocate staticaly
>>> wthout separate function.
>>
>> I think making mfd_cells members of struct mxs-lradc will address all
>> review comments.
>
> No, please don't do that either.
>
It'd be nice if you explained in detail why not. Otherwise this is just 
empty splat.

-- 
Best regards,
Marek Vasut

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Marek Vasut]

On 07/13/2016 02:49 PM, Lee Jones wrote:
> On Fri, 01 Jul 2016, Harald Geyer wrote:
>
>> Hi Ksenija!
>>
>> Ksenija Stanojević writes:
>>> On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones@linaro.org> wrote:
>>>>> +static int mxs_lradc_add_device(struct platform_device *pdev,
>>>>> +                             struct mxs_lradc *lradc, char *name, int i)
>>>>> +{
>>>>> +     struct mfd_cell *cell;
>>>>> +
>>>>> +     cell = &lradc->cells[i];
>>>>> +     cell->name = name;
>>>>> +     cell->platform_data = lradc;
>>>>> +     cell->pdata_size = sizeof(*lradc);
>>>>> +
>>>>> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
>>>>> +}
>>>>
>>>> Please don't roll your own API.
>>>>
>>>> Use 'struct mfd_cell' like everyone else does.
>>>
>>> It has been suggested in previous reviews to use separate function to
>>> register mfd device, and to make mfd_cell allocate dynamically because
>>> struc mxs-lradc is allocated dynamically.
>>> But I can revrse changes and make mfd_cells allocate staticaly
>>> wthout separate function.
>>
>> I think making mfd_cells members of struct mxs-lradc will address all
>> review comments.
>
> No, please don't do that either.
>
It'd be nice if you explained in detail why not. Otherwise this is just 
empty splat.

-- 
Best regards,
Marek Vasut

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Stefan Wahren]

Hi,

> Marek Vasut <marex@denx.de> hat am 14. Juli 2016 um 17:38 geschrieben:
> 
> 
> On 07/13/2016 02:49 PM, Lee Jones wrote:
> > On Fri, 01 Jul 2016, Harald Geyer wrote:
> >
> >> Hi Ksenija!
> >>
> >> Ksenija Stanojević writes:
> >>> On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones@linaro.org> wrote:
> >>>>> +static int mxs_lradc_add_device(struct platform_device *pdev,
> >>>>> +                             struct mxs_lradc *lradc, char *name, int
> >>>>> i)
> >>>>> +{
> >>>>> +     struct mfd_cell *cell;
> >>>>> +
> >>>>> +     cell = &lradc->cells[i];
> >>>>> +     cell->name = name;
> >>>>> +     cell->platform_data = lradc;
> >>>>> +     cell->pdata_size = sizeof(*lradc);
> >>>>> +
> >>>>> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0,
> >>>>> NULL);
> >>>>> +}
> >>>>
> >>>> Please don't roll your own API.
> >>>>
> >>>> Use 'struct mfd_cell' like everyone else does.
> >>>
> >>> It has been suggested in previous reviews to use separate function to
> >>> register mfd device, and to make mfd_cell allocate dynamically because
> >>> struc mxs-lradc is allocated dynamically.
> >>> But I can revrse changes and make mfd_cells allocate staticaly
> >>> wthout separate function.
> >>
> >> I think making mfd_cells members of struct mxs-lradc will address all
> >> review comments.
> >
> > No, please don't do that either.
> >
> It'd be nice if you explained in detail why not. Otherwise this is just 
> empty splat.

since there is no reply, here is my guess:

static const struct mfd_cell mxs_lradc_devs[] = {
	{
		.name = DRIVER_NAME_ADC,
	},
	{
		.name = DRIVER_NAME_TS,
	},
};

But i'm not sure if we need of_compatible defined here. The intension of this
patch series is to keep the DT binding.

@Lee: Could you please give us a feedback?

@Ksenija: Still motivated for next round?

Regards
Stefan

> 
> -- 
> Best regards,
> Marek Vasut

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojević]

Hi,

On Tue, Aug 2, 2016 at 6:35 PM, Stefan Wahren <stefan.wahren@i2se.com> wrote:
> Hi,
>
>> Marek Vasut <marex@denx.de> hat am 14. Juli 2016 um 17:38 geschrieben:
>>
>>
>> On 07/13/2016 02:49 PM, Lee Jones wrote:
>> > On Fri, 01 Jul 2016, Harald Geyer wrote:
>> >
>> >> Hi Ksenija!
>> >>
>> >> Ksenija Stanojević writes:
>> >>> On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones@linaro.org> wrote:
>> >>>>> +static int mxs_lradc_add_device(struct platform_device *pdev,
>> >>>>> +                             struct mxs_lradc *lradc, char *name, int
>> >>>>> i)
>> >>>>> +{
>> >>>>> +     struct mfd_cell *cell;
>> >>>>> +
>> >>>>> +     cell = &lradc->cells[i];
>> >>>>> +     cell->name = name;
>> >>>>> +     cell->platform_data = lradc;
>> >>>>> +     cell->pdata_size = sizeof(*lradc);
>> >>>>> +
>> >>>>> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0,
>> >>>>> NULL);
>> >>>>> +}
>> >>>>
>> >>>> Please don't roll your own API.
>> >>>>
>> >>>> Use 'struct mfd_cell' like everyone else does.
>> >>>
>> >>> It has been suggested in previous reviews to use separate function to
>> >>> register mfd device, and to make mfd_cell allocate dynamically because
>> >>> struc mxs-lradc is allocated dynamically.
>> >>> But I can revrse changes and make mfd_cells allocate staticaly
>> >>> wthout separate function.
>> >>
>> >> I think making mfd_cells members of struct mxs-lradc will address all
>> >> review comments.
>> >
>> > No, please don't do that either.
>> >
>> It'd be nice if you explained in detail why not. Otherwise this is just
>> empty splat.
>
> since there is no reply, here is my guess:

Sorry for the delay, I'm currently working on it. I will post another
version soon.

> static const struct mfd_cell mxs_lradc_devs[] = {
>         {
>                 .name = DRIVER_NAME_ADC,
>         },
>         {
>                 .name = DRIVER_NAME_TS,
>         },
> };
>
> But i'm not sure if we need of_compatible defined here. The intension of this
> patch series is to keep the DT binding.

I think it needs .resources because in next version DEFINE_RES_IRQ_NAMED
will be used.

> @Lee: Could you please give us a feedback?
>
> @Ksenija: Still motivated for next round?
>
> Regards
> Stefan
>
>>
>> --
>> Best regards,
>> Marek Vasut

Regards,
Ksenija

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojević]

Hi All,

On Tue, Aug 2, 2016 at 7:08 PM, Ksenija Stanojević
<ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> Hi,
>
> On Tue, Aug 2, 2016 at 6:35 PM, Stefan Wahren <stefan.wahren-eS4NqCHxEME@public.gmane.org> wrote:
>> Hi,
>>
>>> Marek Vasut <marex-ynQEQJNshbs@public.gmane.org> hat am 14. Juli 2016 um 17:38 geschrieben:
>>>
>>>
>>> On 07/13/2016 02:49 PM, Lee Jones wrote:
>>> > On Fri, 01 Jul 2016, Harald Geyer wrote:
>>> >
>>> >> Hi Ksenija!
>>> >>
>>> >> Ksenija Stanojević writes:
>>> >>> On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> wrote:
>>> >>>>> +static int mxs_lradc_add_device(struct platform_device *pdev,
>>> >>>>> +                             struct mxs_lradc *lradc, char *name, int
>>> >>>>> i)
>>> >>>>> +{
>>> >>>>> +     struct mfd_cell *cell;
>>> >>>>> +
>>> >>>>> +     cell = &lradc->cells[i];
>>> >>>>> +     cell->name = name;
>>> >>>>> +     cell->platform_data = lradc;
>>> >>>>> +     cell->pdata_size = sizeof(*lradc);
>>> >>>>> +
>>> >>>>> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0,
>>> >>>>> NULL);
>>> >>>>> +}
>>> >>>>
>>> >>>> Please don't roll your own API.
>>> >>>>
>>> >>>> Use 'struct mfd_cell' like everyone else does.
>>> >>>
>>> >>> It has been suggested in previous reviews to use separate function to
>>> >>> register mfd device, and to make mfd_cell allocate dynamically because
>>> >>> struc mxs-lradc is allocated dynamically.
>>> >>> But I can revrse changes and make mfd_cells allocate staticaly
>>> >>> wthout separate function.
>>> >>
>>> >> I think making mfd_cells members of struct mxs-lradc will address all
>>> >> review comments.
>>> >
>>> > No, please don't do that either.
>>> >
>>> It'd be nice if you explained in detail why not. Otherwise this is just
>>> empty splat.
>>
>> since there is no reply, here is my guess:
>
> Sorry for the delay, I'm currently working on it. I will post another
> version soon.
>
>> static const struct mfd_cell mxs_lradc_devs[] = {
>>         {
>>                 .name = DRIVER_NAME_ADC,
>>         },
>>         {
>>                 .name = DRIVER_NAME_TS,
>>         },
>> };
>>
>> But i'm not sure if we need of_compatible defined here. The intension of this
>> patch series is to keep the DT binding.
>
> I think it needs .resources because in next version DEFINE_RES_IRQ_NAMED
> will be used.
>
>> @Lee: Could you please give us a feedback?
>>
>> @Ksenija: Still motivated for next round?

Can someone with imx23 board send me /proc/interrupts log, I
need irq numbers...

Thanks,
Ksenija

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojević]

Hi All,

On Tue, Aug 2, 2016 at 7:08 PM, Ksenija Stanojević
<ksenija.stanojevic@gmail.com> wrote:
> Hi,
>
> On Tue, Aug 2, 2016 at 6:35 PM, Stefan Wahren <stefan.wahren@i2se.com> wrote:
>> Hi,
>>
>>> Marek Vasut <marex@denx.de> hat am 14. Juli 2016 um 17:38 geschrieben:
>>>
>>>
>>> On 07/13/2016 02:49 PM, Lee Jones wrote:
>>> > On Fri, 01 Jul 2016, Harald Geyer wrote:
>>> >
>>> >> Hi Ksenija!
>>> >>
>>> >> Ksenija Stanojević writes:
>>> >>> On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones@linaro.org> wrote:
>>> >>>>> +static int mxs_lradc_add_device(struct platform_device *pdev,
>>> >>>>> +                             struct mxs_lradc *lradc, char *name, int
>>> >>>>> i)
>>> >>>>> +{
>>> >>>>> +     struct mfd_cell *cell;
>>> >>>>> +
>>> >>>>> +     cell = &lradc->cells[i];
>>> >>>>> +     cell->name = name;
>>> >>>>> +     cell->platform_data = lradc;
>>> >>>>> +     cell->pdata_size = sizeof(*lradc);
>>> >>>>> +
>>> >>>>> +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0,
>>> >>>>> NULL);
>>> >>>>> +}
>>> >>>>
>>> >>>> Please don't roll your own API.
>>> >>>>
>>> >>>> Use 'struct mfd_cell' like everyone else does.
>>> >>>
>>> >>> It has been suggested in previous reviews to use separate function to
>>> >>> register mfd device, and to make mfd_cell allocate dynamically because
>>> >>> struc mxs-lradc is allocated dynamically.
>>> >>> But I can revrse changes and make mfd_cells allocate staticaly
>>> >>> wthout separate function.
>>> >>
>>> >> I think making mfd_cells members of struct mxs-lradc will address all
>>> >> review comments.
>>> >
>>> > No, please don't do that either.
>>> >
>>> It'd be nice if you explained in detail why not. Otherwise this is just
>>> empty splat.
>>
>> since there is no reply, here is my guess:
>
> Sorry for the delay, I'm currently working on it. I will post another
> version soon.
>
>> static const struct mfd_cell mxs_lradc_devs[] = {
>>         {
>>                 .name = DRIVER_NAME_ADC,
>>         },
>>         {
>>                 .name = DRIVER_NAME_TS,
>>         },
>> };
>>
>> But i'm not sure if we need of_compatible defined here. The intension of this
>> patch series is to keep the DT binding.
>
> I think it needs .resources because in next version DEFINE_RES_IRQ_NAMED
> will be used.
>
>> @Lee: Could you please give us a feedback?
>>
>> @Ksenija: Still motivated for next round?

Can someone with imx23 board send me /proc/interrupts log, I
need irq numbers...

Thanks,
Ksenija

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Fabio Estevam]

Hi Ksenija,

On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
<ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:

> Can someone with imx23 board send me /proc/interrupts log, I
> need irq numbers...

Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
Interrupt Sources)?

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Fabio Estevam]

Hi Ksenija,

On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
<ksenija.stanojevic@gmail.com> wrote:

> Can someone with imx23 board send me /proc/interrupts log, I
> need irq numbers...

Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
Interrupt Sources)?

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojević]

Hi Fabio,

On Wed, Aug 3, 2016 at 6:35 PM, Fabio Estevam <festevam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> Hi Ksenija,
>
> On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
> <ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
>> Can someone with imx23 board send me /proc/interrupts log, I
>> need irq numbers...
>
> Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
> Interrupt Sources)?

I thought it will be more reliable if I asked someone, since numbers from MX28
manual don't match with /proc/interrupts log.

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojević]

Hi Fabio,

On Wed, Aug 3, 2016 at 6:35 PM, Fabio Estevam <festevam@gmail.com> wrote:
> Hi Ksenija,
>
> On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
> <ksenija.stanojevic@gmail.com> wrote:
>
>> Can someone with imx23 board send me /proc/interrupts log, I
>> need irq numbers...
>
> Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
> Interrupt Sources)?

I thought it will be more reliable if I asked someone, since numbers from MX28
manual don't match with /proc/interrupts log.

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Marek Vasut]

On 08/03/2016 06:45 PM, Ksenija Stanojević wrote:
> Hi Fabio,

Hi,

> On Wed, Aug 3, 2016 at 6:35 PM, Fabio Estevam <festevam@gmail.com> wrote:
>> Hi Ksenija,
>>
>> On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
>> <ksenija.stanojevic@gmail.com> wrote:
>>
>>> Can someone with imx23 board send me /proc/interrupts log, I
>>> need irq numbers...
>>
>> Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
>> Interrupt Sources)?
> 
> I thought it will be more reliable if I asked someone, since numbers from MX28
> manual don't match with /proc/interrupts log.
> 
What do you mean they don't match ? Please elaborate.

-- 
Best regards,
Marek Vasut

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojević]

On Wed, Aug 3, 2016 at 9:13 PM, Marek Vasut <marex-ynQEQJNshbs@public.gmane.org> wrote:
> On 08/03/2016 06:45 PM, Ksenija Stanojević wrote:
>> Hi Fabio,
>
> Hi,
>
>> On Wed, Aug 3, 2016 at 6:35 PM, Fabio Estevam <festevam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>>> Hi Ksenija,
>>>
>>> On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
>>> <ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>>>
>>>> Can someone with imx23 board send me /proc/interrupts log, I
>>>> need irq numbers...
>>>
>>> Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
>>> Interrupt Sources)?
>>
>> I thought it will be more reliable if I asked someone, since numbers from MX28
>> manual don't match with /proc/interrupts log.
>>
> What do you mean they don't match ? Please elaborate.

irqs don't have the same values in Table 5.1 in MX28 manual and in
/proc/interrupts
output.

For example:
touchscreen irq in MX28 manual have these values:
10 (source number) and 0x0028 (vector number)

in /proc/interrupts:
210:          0         -  10 Edge      mxs-lradc-touchscreen

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojević]

On Wed, Aug 3, 2016 at 9:13 PM, Marek Vasut <marex@denx.de> wrote:
> On 08/03/2016 06:45 PM, Ksenija Stanojević wrote:
>> Hi Fabio,
>
> Hi,
>
>> On Wed, Aug 3, 2016 at 6:35 PM, Fabio Estevam <festevam@gmail.com> wrote:
>>> Hi Ksenija,
>>>
>>> On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
>>> <ksenija.stanojevic@gmail.com> wrote:
>>>
>>>> Can someone with imx23 board send me /proc/interrupts log, I
>>>> need irq numbers...
>>>
>>> Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
>>> Interrupt Sources)?
>>
>> I thought it will be more reliable if I asked someone, since numbers from MX28
>> manual don't match with /proc/interrupts log.
>>
> What do you mean they don't match ? Please elaborate.

irqs don't have the same values in Table 5.1 in MX28 manual and in
/proc/interrupts
output.

For example:
touchscreen irq in MX28 manual have these values:
10 (source number) and 0x0028 (vector number)

in /proc/interrupts:
210:          0         -  10 Edge      mxs-lradc-touchscreen

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Marek Vasut]

On 08/03/2016 09:34 PM, Ksenija Stanojević wrote:
> On Wed, Aug 3, 2016 at 9:13 PM, Marek Vasut <marex-ynQEQJNshbs@public.gmane.org> wrote:
>> On 08/03/2016 06:45 PM, Ksenija Stanojević wrote:
>>> Hi Fabio,
>>
>> Hi,
>>
>>> On Wed, Aug 3, 2016 at 6:35 PM, Fabio Estevam <festevam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>>>> Hi Ksenija,
>>>>
>>>> On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
>>>> <ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>>>>
>>>>> Can someone with imx23 board send me /proc/interrupts log, I
>>>>> need irq numbers...
>>>>
>>>> Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
>>>> Interrupt Sources)?
>>>
>>> I thought it will be more reliable if I asked someone, since numbers from MX28
>>> manual don't match with /proc/interrupts log.
>>>
>> What do you mean they don't match ? Please elaborate.
> 
> irqs don't have the same values in Table 5.1 in MX28 manual and in
> /proc/interrupts
> output.
> 
> For example:
> touchscreen irq in MX28 manual have these values:
> 10 (source number) and 0x0028 (vector number)
> 
> in /proc/interrupts:
> 210:          0         -  10 Edge      mxs-lradc-touchscreen

I see lradc_touch_irq in the MX28RM is IRQ 10 and it is also 10 in your
/proc/interrupts output . What am I missing ?

-- 
Best regards,
Marek Vasut

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Marek Vasut]

On 08/03/2016 09:34 PM, Ksenija Stanojević wrote:
> On Wed, Aug 3, 2016 at 9:13 PM, Marek Vasut <marex@denx.de> wrote:
>> On 08/03/2016 06:45 PM, Ksenija Stanojević wrote:
>>> Hi Fabio,
>>
>> Hi,
>>
>>> On Wed, Aug 3, 2016 at 6:35 PM, Fabio Estevam <festevam@gmail.com> wrote:
>>>> Hi Ksenija,
>>>>
>>>> On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
>>>> <ksenija.stanojevic@gmail.com> wrote:
>>>>
>>>>> Can someone with imx23 board send me /proc/interrupts log, I
>>>>> need irq numbers...
>>>>
>>>> Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
>>>> Interrupt Sources)?
>>>
>>> I thought it will be more reliable if I asked someone, since numbers from MX28
>>> manual don't match with /proc/interrupts log.
>>>
>> What do you mean they don't match ? Please elaborate.
> 
> irqs don't have the same values in Table 5.1 in MX28 manual and in
> /proc/interrupts
> output.
> 
> For example:
> touchscreen irq in MX28 manual have these values:
> 10 (source number) and 0x0028 (vector number)
> 
> in /proc/interrupts:
> 210:          0         -  10 Edge      mxs-lradc-touchscreen

I see lradc_touch_irq in the MX28RM is IRQ 10 and it is also 10 in your
/proc/interrupts output . What am I missing ?

-- 
Best regards,
Marek Vasut

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojević]

On Wed, Aug 3, 2016 at 9:39 PM, Marek Vasut <marex@denx.de> wrote:
> On 08/03/2016 09:34 PM, Ksenija Stanojević wrote:
>> On Wed, Aug 3, 2016 at 9:13 PM, Marek Vasut <marex@denx.de> wrote:
>>> On 08/03/2016 06:45 PM, Ksenija Stanojević wrote:
>>>> Hi Fabio,
>>>
>>> Hi,
>>>
>>>> On Wed, Aug 3, 2016 at 6:35 PM, Fabio Estevam <festevam@gmail.com> wrote:
>>>>> Hi Ksenija,
>>>>>
>>>>> On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
>>>>> <ksenija.stanojevic@gmail.com> wrote:
>>>>>
>>>>>> Can someone with imx23 board send me /proc/interrupts log, I
>>>>>> need irq numbers...
>>>>>
>>>>> Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
>>>>> Interrupt Sources)?
>>>>
>>>> I thought it will be more reliable if I asked someone, since numbers from MX28
>>>> manual don't match with /proc/interrupts log.
>>>>
>>> What do you mean they don't match ? Please elaborate.
>>
>> irqs don't have the same values in Table 5.1 in MX28 manual and in
>> /proc/interrupts
>> output.
>>
>> For example:
>> touchscreen irq in MX28 manual have these values:
>> 10 (source number) and 0x0028 (vector number)
>>
>> in /proc/interrupts:
>> 210:          0         -  10 Edge      mxs-lradc-touchscreen
>
> I see lradc_touch_irq in the MX28RM is IRQ 10 and it is also 10 in your
> /proc/interrupts output . What am I missing ?

I was referring to the number of the first column 210, that's the number that
I need and cannot find in the Table of the manual.

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Marek Vasut]

On 08/03/2016 09:45 PM, Ksenija Stanojević wrote:
> On Wed, Aug 3, 2016 at 9:39 PM, Marek Vasut <marex@denx.de> wrote:
>> On 08/03/2016 09:34 PM, Ksenija Stanojević wrote:
>>> On Wed, Aug 3, 2016 at 9:13 PM, Marek Vasut <marex@denx.de> wrote:
>>>> On 08/03/2016 06:45 PM, Ksenija Stanojević wrote:
>>>>> Hi Fabio,
>>>>
>>>> Hi,
>>>>
>>>>> On Wed, Aug 3, 2016 at 6:35 PM, Fabio Estevam <festevam@gmail.com> wrote:
>>>>>> Hi Ksenija,
>>>>>>
>>>>>> On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
>>>>>> <ksenija.stanojevic@gmail.com> wrote:
>>>>>>
>>>>>>> Can someone with imx23 board send me /proc/interrupts log, I
>>>>>>> need irq numbers...
>>>>>>
>>>>>> Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
>>>>>> Interrupt Sources)?
>>>>>
>>>>> I thought it will be more reliable if I asked someone, since numbers from MX28
>>>>> manual don't match with /proc/interrupts log.
>>>>>
>>>> What do you mean they don't match ? Please elaborate.
>>>
>>> irqs don't have the same values in Table 5.1 in MX28 manual and in
>>> /proc/interrupts
>>> output.
>>>
>>> For example:
>>> touchscreen irq in MX28 manual have these values:
>>> 10 (source number) and 0x0028 (vector number)
>>>
>>> in /proc/interrupts:
>>> 210:          0         -  10 Edge      mxs-lradc-touchscreen
>>
>> I see lradc_touch_irq in the MX28RM is IRQ 10 and it is also 10 in your
>> /proc/interrupts output . What am I missing ?
> 
> I was referring to the number of the first column 210, that's the number that
> I need and cannot find in the Table of the manual.

The first number in /proc/interrupts is the number which Linux maps to
that particular IRQ line, but that number can be anything, it does not
(need to) match the hardware in any way. What do you need it for ?

-- 
Best regards,
Marek Vasut

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Ksenija Stanojević]

On Wed, Aug 3, 2016 at 9:57 PM, Marek Vasut <marex@denx.de> wrote:
> On 08/03/2016 09:45 PM, Ksenija Stanojević wrote:
>> On Wed, Aug 3, 2016 at 9:39 PM, Marek Vasut <marex@denx.de> wrote:
>>> On 08/03/2016 09:34 PM, Ksenija Stanojević wrote:
>>>> On Wed, Aug 3, 2016 at 9:13 PM, Marek Vasut <marex@denx.de> wrote:
>>>>> On 08/03/2016 06:45 PM, Ksenija Stanojević wrote:
>>>>>> Hi Fabio,
>>>>>
>>>>> Hi,
>>>>>
>>>>>> On Wed, Aug 3, 2016 at 6:35 PM, Fabio Estevam <festevam@gmail.com> wrote:
>>>>>>> Hi Ksenija,
>>>>>>>
>>>>>>> On Wed, Aug 3, 2016 at 1:32 PM, Ksenija Stanojević
>>>>>>> <ksenija.stanojevic@gmail.com> wrote:
>>>>>>>
>>>>>>>> Can someone with imx23 board send me /proc/interrupts log, I
>>>>>>>> need irq numbers...
>>>>>>>
>>>>>>> Can't you get them from the MX23 Reference Manual (Table 5-1. i.MX23
>>>>>>> Interrupt Sources)?
>>>>>>
>>>>>> I thought it will be more reliable if I asked someone, since numbers from MX28
>>>>>> manual don't match with /proc/interrupts log.
>>>>>>
>>>>> What do you mean they don't match ? Please elaborate.
>>>>
>>>> irqs don't have the same values in Table 5.1 in MX28 manual and in
>>>> /proc/interrupts
>>>> output.
>>>>
>>>> For example:
>>>> touchscreen irq in MX28 manual have these values:
>>>> 10 (source number) and 0x0028 (vector number)
>>>>
>>>> in /proc/interrupts:
>>>> 210:          0         -  10 Edge      mxs-lradc-touchscreen
>>>
>>> I see lradc_touch_irq in the MX28RM is IRQ 10 and it is also 10 in your
>>> /proc/interrupts output . What am I missing ?
>>
>> I was referring to the number of the first column 210, that's the number that
>> I need and cannot find in the Table of the manual.
>
> The first number in /proc/interrupts is the number which Linux maps to
> that particular IRQ line, but that number can be anything, it does not
> (need to) match the hardware in any way. What do you need it for ?

Thanks, I didn't know that. Well I was using the first number to map
irq names to irq number in DEFINE_RES_IRQ_NAMED.
Otherwise I get probe failure:
probe of mxs-lradc-ts failed with error -22

It's because platform_get_irq_byname cannot find irq for the given
irq name.

Re: [PATCH v3 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

[Lee Jones]

On Thu, 14 Jul 2016, Marek Vasut wrote:

> On 07/13/2016 02:49 PM, Lee Jones wrote:
> > On Fri, 01 Jul 2016, Harald Geyer wrote:
> > 
> > > Hi Ksenija!
> > > 
> > > Ksenija Stanojević writes:
> > > > On Tue, Jun 28, 2016 at 6:28 PM, Lee Jones <lee.jones@linaro.org> wrote:
> > > > > > +static int mxs_lradc_add_device(struct platform_device *pdev,
> > > > > > +                             struct mxs_lradc *lradc, char *name, int i)
> > > > > > +{
> > > > > > +     struct mfd_cell *cell;
> > > > > > +
> > > > > > +     cell = &lradc->cells[i];
> > > > > > +     cell->name = name;
> > > > > > +     cell->platform_data = lradc;
> > > > > > +     cell->pdata_size = sizeof(*lradc);
> > > > > > +
> > > > > > +     return devm_mfd_add_devices(&pdev->dev, -1, cell, 1, NULL, 0, NULL);
> > > > > > +}
> > > > > 
> > > > > Please don't roll your own API.
> > > > > 
> > > > > Use 'struct mfd_cell' like everyone else does.
> > > > 
> > > > It has been suggested in previous reviews to use separate function to
> > > > register mfd device, and to make mfd_cell allocate dynamically because
> > > > struc mxs-lradc is allocated dynamically.
> > > > But I can revrse changes and make mfd_cells allocate staticaly
> > > > wthout separate function.
> > > 
> > > I think making mfd_cells members of struct mxs-lradc will address all
> > > review comments.
> > 
> > No, please don't do that either.
> > 
> It'd be nice if you explained in detail why not. Otherwise this is just
> empty splat.

I already said what needs to be done.

"Use struct mfd_cell", in it's pure/static form.  Don't include it in
any device data struct.

"like everyone else does", look at other driver to see how they do
it.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

[PATCH v3 2/4] iio: adc: mxs-lradc: Add support for adc driver

[Ksenija Stanojevic]

Add support for sixteen-channel 12-bit resolution ADC and its functions,
which include general-purpose ADC readings, battery voltage measurement,
and die temperature measurement.

Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Acked-by: Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
---
Changes in v3:
 - make buffer large enough for timestamps
 - remove unnecessary blank lines

Changes in v2:
 - improve commit message
 - do not change spacing in Kconfig
 - impove formating
 - remove wrapper show_scale_avail
 - use correct syntax for comments
 - use devm_iio_trigger_alloc
 - do not allocate buffer dynamically 
 - use iio_device_claim_*_mode helpers
 - add spinlock in struct mxs_lradc_ts to enable locking in interrupt handler
 - only grab irqs that are relevant to adc
 - remove blank line at the end of the file
 - change licence to GPL
 - add copyright

 drivers/iio/adc/Kconfig         |  13 +
 drivers/iio/adc/Makefile        |   1 +
 drivers/iio/adc/mxs-lradc-adc.c | 811 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 825 insertions(+)
 create mode 100644 drivers/iio/adc/mxs-lradc-adc.c

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 932de1f..4ef3ad1 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -194,6 +194,19 @@ config EXYNOS_ADC
 	  To compile this driver as a module, choose M here: the module will be
 	  called exynos_adc.
 
+config MXS_LRADC_ADC
+	tristate "Freescale i.MX23/i.MX28 LRADC ADC"
+	depends on MFD_MXS_LRADC
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	  Say yes here to build support for the ADC functions of the
+	  i.MX23/i.MX28 LRADC. This includes general-purpose ADC readings,
+	  battery voltage measurement, and die temperature measurement.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called mxs-lradc-adc.
+
 config HI8435
 	tristate "Holt Integrated Circuits HI-8435 threshold detector"
 	select IIO_TRIGGERED_EVENT
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index b1aa456..9bb35c4 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_MAX1363) += max1363.o
 obj-$(CONFIG_MCP320X) += mcp320x.o
 obj-$(CONFIG_MCP3422) += mcp3422.o
 obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o
+obj-$(CONFIG_MXS_LRADC_ADC) += mxs-lradc-adc.o
 obj-$(CONFIG_MXS_LRADC) += mxs-lradc.o
 obj-$(CONFIG_NAU7802) += nau7802.o
 obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o
diff --git a/drivers/iio/adc/mxs-lradc-adc.c b/drivers/iio/adc/mxs-lradc-adc.c
new file mode 100644
index 0000000..9d33fe3
--- /dev/null
+++ b/drivers/iio/adc/mxs-lradc-adc.c
@@ -0,0 +1,811 @@
+/*
+ * Freescale MXS LRADC ADC driver
+ *
+ * Copyright (c) 2012 DENX Software Engineering, GmbH.
+ * Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>
+ * Ksenija Stanojevic <ksenija.stanojevic-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/mxs-lradc.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/sysfs.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/sysfs.h>
+
+/*
+ * Make this runtime configurable if necessary. Currently, if the buffered mode
+ * is enabled, the LRADC takes LRADC_DELAY_TIMER_LOOP samples of data before
+ * triggering IRQ. The sampling happens every (LRADC_DELAY_TIMER_PER / 2000)
+ * seconds. The result is that the samples arrive every 500mS.
+ */
+#define LRADC_DELAY_TIMER_PER	200
+#define LRADC_DELAY_TIMER_LOOP	5
+
+#define VREF_MV_BASE 1850
+
+#define IMX23_NUM_IRQ 6
+#define IMX28_NUM_IRQ 10
+
+static const int mx23_lradc_adc_irq[] = {1, 2, 3, 4, 5, 6};
+static const int mx28_lradc_adc_irq[] = {1, 2, 3, 4, 5, 6, 7, 8, 11, 12};
+
+static const u32 mxs_lradc_adc_vref_mv[][LRADC_MAX_TOTAL_CHANS] = {
+	[IMX23_LRADC] = {
+		VREF_MV_BASE,		/* CH0 */
+		VREF_MV_BASE,		/* CH1 */
+		VREF_MV_BASE,		/* CH2 */
+		VREF_MV_BASE,		/* CH3 */
+		VREF_MV_BASE,		/* CH4 */
+		VREF_MV_BASE,		/* CH5 */
+		VREF_MV_BASE * 2,	/* CH6 VDDIO */
+		VREF_MV_BASE * 4,	/* CH7 VBATT */
+		VREF_MV_BASE,		/* CH8 Temp sense 0 */
+		VREF_MV_BASE,		/* CH9 Temp sense 1 */
+		VREF_MV_BASE,		/* CH10 */
+		VREF_MV_BASE,		/* CH11 */
+		VREF_MV_BASE,		/* CH12 USB_DP */
+		VREF_MV_BASE,		/* CH13 USB_DN */
+		VREF_MV_BASE,		/* CH14 VBG */
+		VREF_MV_BASE * 4,	/* CH15 VDD5V */
+	},
+	[IMX28_LRADC] = {
+		VREF_MV_BASE,		/* CH0 */
+		VREF_MV_BASE,		/* CH1 */
+		VREF_MV_BASE,		/* CH2 */
+		VREF_MV_BASE,		/* CH3 */
+		VREF_MV_BASE,		/* CH4 */
+		VREF_MV_BASE,		/* CH5 */
+		VREF_MV_BASE,		/* CH6 */
+		VREF_MV_BASE * 4,	/* CH7 VBATT */
+		VREF_MV_BASE,		/* CH8 Temp sense 0 */
+		VREF_MV_BASE,		/* CH9 Temp sense 1 */
+		VREF_MV_BASE * 2,	/* CH10 VDDIO */
+		VREF_MV_BASE,		/* CH11 VTH */
+		VREF_MV_BASE * 2,	/* CH12 VDDA */
+		VREF_MV_BASE,		/* CH13 VDDD */
+		VREF_MV_BASE,		/* CH14 VBG */
+		VREF_MV_BASE * 4,	/* CH15 VDD5V */
+	},
+};
+
+enum mxs_lradc_divbytwo {
+	MXS_LRADC_DIV_DISABLED = 0,
+	MXS_LRADC_DIV_ENABLED,
+};
+
+struct mxs_lradc_scale {
+	unsigned int		integer;
+	unsigned int		nano;
+};
+
+struct mxs_lradc_adc {
+	struct mxs_lradc	*lradc;
+	struct device		*dev;
+
+	u32			buffer[10];
+	struct iio_trigger	*trig;
+	struct completion	completion;
+	spinlock_t		lock;
+
+	const u32		*vref_mv;
+	struct mxs_lradc_scale	scale_avail[LRADC_MAX_TOTAL_CHANS][2];
+	unsigned long		is_divided;
+};
+
+
+/* Raw I/O operations */
+static int mxs_lradc_adc_read_single(struct iio_dev *iio_dev, int chan,
+				     int *val)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio_dev);
+	struct mxs_lradc *lradc = adc->lradc;
+	int ret;
+
+	/*
+	 * See if there is no buffered operation in progress. If there is simply
+	 * bail out. This can be improved to support both buffered and raw IO at
+	 * the same time, yet the code becomes horribly complicated. Therefore I
+	 * applied KISS principle here.
+	 */
+	ret = iio_device_claim_direct_mode(iio_dev);
+	if (ret)
+		return ret;
+
+	reinit_completion(&adc->completion);
+
+	/*
+	 * No buffered operation in progress, map the channel and trigger it.
+	 * Virtual channel 0 is always used here as the others are always not
+	 * used if doing raw sampling.
+	 */
+	if (lradc->soc == IMX28_LRADC)
+		mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0),
+				    LRADC_CTRL1);
+	mxs_lradc_reg_clear(lradc, 0x1, LRADC_CTRL0);
+
+	/* Enable / disable the divider per requirement */
+	if (test_bit(chan, &adc->is_divided))
+		mxs_lradc_reg_set(lradc,
+				  1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
+				  LRADC_CTRL2);
+	else
+		mxs_lradc_reg_clear(lradc,
+				    1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
+				    LRADC_CTRL2);
+
+	/* Clean the slot's previous content, then set new one. */
+	mxs_lradc_reg_clear(lradc, LRADC_CTRL4_LRADCSELECT_MASK(0),
+			    LRADC_CTRL4);
+	mxs_lradc_reg_set(lradc, chan, LRADC_CTRL4);
+
+	mxs_lradc_reg_wrt(lradc, 0, LRADC_CH(0));
+
+	/* Enable the IRQ and start sampling the channel. */
+	mxs_lradc_reg_set(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1);
+	mxs_lradc_reg_set(lradc, BIT(0), LRADC_CTRL0);
+
+	/* Wait for completion on the channel, 1 second max. */
+	ret = wait_for_completion_killable_timeout(&adc->completion, HZ);
+	if (!ret)
+		ret = -ETIMEDOUT;
+	if (ret < 0)
+		goto err;
+
+	/* Read the data. */
+	*val = readl(lradc->base + LRADC_CH(0)) & LRADC_CH_VALUE_MASK;
+	ret = IIO_VAL_INT;
+
+err:
+	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1);
+
+	iio_device_release_direct_mode(iio_dev);
+
+	return ret;
+}
+
+static int mxs_lradc_adc_read_temp(struct iio_dev *iio_dev, int *val)
+{
+	int ret, min, max;
+
+	ret = mxs_lradc_adc_read_single(iio_dev, 8, &min);
+	if (ret != IIO_VAL_INT)
+		return ret;
+
+	ret = mxs_lradc_adc_read_single(iio_dev, 9, &max);
+	if (ret != IIO_VAL_INT)
+		return ret;
+
+	*val = max - min;
+
+	return IIO_VAL_INT;
+}
+
+static int mxs_lradc_adc_read_raw(struct iio_dev *iio_dev,
+			      const struct iio_chan_spec *chan,
+			      int *val, int *val2, long m)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio_dev);
+
+	switch (m) {
+	case IIO_CHAN_INFO_RAW:
+		if (chan->type == IIO_TEMP)
+			return mxs_lradc_adc_read_temp(iio_dev, val);
+
+		return mxs_lradc_adc_read_single(iio_dev, chan->channel, val);
+
+	case IIO_CHAN_INFO_SCALE:
+		if (chan->type == IIO_TEMP) {
+			/*
+			 * From the datasheet, we have to multiply by 1.012 and
+			 * divide by 4
+			 */
+			*val = 0;
+			*val2 = 253000;
+			return IIO_VAL_INT_PLUS_MICRO;
+		}
+
+		*val = adc->vref_mv[chan->channel];
+		*val2 = chan->scan_type.realbits -
+			test_bit(chan->channel, &adc->is_divided);
+		return IIO_VAL_FRACTIONAL_LOG2;
+
+	case IIO_CHAN_INFO_OFFSET:
+		if (chan->type == IIO_TEMP) {
+			/*
+			 * The calculated value from the ADC is in Kelvin, we
+			 * want Celsius for hwmon so the offset is -273.15
+			 * The offset is applied before scaling so it is
+			 * actually -213.15 * 4 / 1.012 = -1079.644268
+			 */
+			*val = -1079;
+			*val2 = 644268;
+
+			return IIO_VAL_INT_PLUS_MICRO;
+		}
+
+		return -EINVAL;
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int mxs_lradc_adc_write_raw(struct iio_dev *iio_dev,
+				   const struct iio_chan_spec *chan,
+				   int val, int val2, long m)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio_dev);
+	struct mxs_lradc_scale *scale_avail =
+			adc->scale_avail[chan->channel];
+	int ret;
+
+	ret = iio_device_claim_direct_mode(iio_dev);
+	if (ret)
+		return ret;
+
+	switch (m) {
+	case IIO_CHAN_INFO_SCALE:
+		ret = -EINVAL;
+		if (val == scale_avail[MXS_LRADC_DIV_DISABLED].integer &&
+		    val2 == scale_avail[MXS_LRADC_DIV_DISABLED].nano) {
+			/* divider by two disabled */
+			clear_bit(chan->channel, &adc->is_divided);
+			ret = 0;
+		} else if (val == scale_avail[MXS_LRADC_DIV_ENABLED].integer &&
+			   val2 == scale_avail[MXS_LRADC_DIV_ENABLED].nano) {
+			/* divider by two enabled */
+			set_bit(chan->channel, &adc->is_divided);
+			ret = 0;
+		}
+
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	iio_device_release_direct_mode(iio_dev);
+
+	return ret;
+}
+
+static int mxs_lradc_adc_write_raw_get_fmt(struct iio_dev *iio_dev,
+					   const struct iio_chan_spec *chan,
+					   long m)
+{
+	return IIO_VAL_INT_PLUS_NANO;
+}
+
+static ssize_t mxs_lradc_adc_show_scale_avail(struct device *dev,
+						 struct device_attribute *attr,
+						 char *buf)
+{
+	struct iio_dev *iio = dev_to_iio_dev(dev);
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	struct iio_dev_attr *iio_attr = to_iio_dev_attr(attr);
+	int i, ch, len = 0;
+
+	ch = iio_attr->address;
+	for (i = 0; i < ARRAY_SIZE(adc->scale_avail[ch]); i++)
+		len += sprintf(buf + len, "%u.%09u ",
+			       adc->scale_avail[ch][i].integer,
+			       adc->scale_avail[ch][i].nano);
+
+	len += sprintf(buf + len, "\n");
+
+	return len;
+}
+
+#define SHOW_SCALE_AVAILABLE_ATTR(ch)					\
+static IIO_DEVICE_ATTR(in_voltage##ch##_scale_available, S_IRUGO,	\
+		       mxs_lradc_adc_show_scale_avail, NULL, ch)
+
+SHOW_SCALE_AVAILABLE_ATTR(0);
+SHOW_SCALE_AVAILABLE_ATTR(1);
+SHOW_SCALE_AVAILABLE_ATTR(2);
+SHOW_SCALE_AVAILABLE_ATTR(3);
+SHOW_SCALE_AVAILABLE_ATTR(4);
+SHOW_SCALE_AVAILABLE_ATTR(5);
+SHOW_SCALE_AVAILABLE_ATTR(6);
+SHOW_SCALE_AVAILABLE_ATTR(7);
+SHOW_SCALE_AVAILABLE_ATTR(10);
+SHOW_SCALE_AVAILABLE_ATTR(11);
+SHOW_SCALE_AVAILABLE_ATTR(12);
+SHOW_SCALE_AVAILABLE_ATTR(13);
+SHOW_SCALE_AVAILABLE_ATTR(14);
+SHOW_SCALE_AVAILABLE_ATTR(15);
+
+static struct attribute *mxs_lradc_adc_attributes[] = {
+	&iio_dev_attr_in_voltage0_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage1_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage2_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage3_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage4_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage5_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage6_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage7_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage10_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage11_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage12_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage13_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage14_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage15_scale_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group mxs_lradc_adc_attribute_group = {
+	.attrs = mxs_lradc_adc_attributes,
+};
+
+static const struct iio_info mxs_lradc_adc_iio_info = {
+	.driver_module		= THIS_MODULE,
+	.read_raw		= mxs_lradc_adc_read_raw,
+	.write_raw		= mxs_lradc_adc_write_raw,
+	.write_raw_get_fmt	= mxs_lradc_adc_write_raw_get_fmt,
+	.attrs			= &mxs_lradc_adc_attribute_group,
+};
+
+/* IRQ Handling */
+static irqreturn_t mxs_lradc_adc_handle_irq(int irq, void *data)
+{
+	struct iio_dev *iio = data;
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	struct mxs_lradc *lradc = adc->lradc;
+	unsigned long reg = readl(lradc->base + LRADC_CTRL1);
+	unsigned long flags;
+
+	if (!(reg & mxs_lradc_irq_mask(lradc)))
+		return IRQ_NONE;
+
+	if (iio_buffer_enabled(iio)) {
+		if (reg & lradc->buffer_vchans) {
+			spin_lock_irqsave(&adc->lock, flags);
+			iio_trigger_poll(iio->trig);
+			spin_unlock_irqrestore(&adc->lock, flags);
+		}
+	} else if (reg & LRADC_CTRL1_LRADC_IRQ(0)) {
+		complete(&adc->completion);
+	}
+
+	mxs_lradc_reg_clear(lradc, reg & mxs_lradc_irq_mask(lradc),
+			    LRADC_CTRL1);
+
+	return IRQ_HANDLED;
+}
+
+
+/* Trigger handling */
+static irqreturn_t mxs_lradc_adc_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *iio = pf->indio_dev;
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	const u32 chan_value = LRADC_CH_ACCUMULATE |
+		((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET);
+	unsigned int i, j = 0;
+
+	for_each_set_bit(i, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
+		adc->buffer[j] = readl(adc->lradc->base + LRADC_CH(j));
+		mxs_lradc_reg_wrt(adc->lradc, chan_value, LRADC_CH(j));
+		adc->buffer[j] &= LRADC_CH_VALUE_MASK;
+		adc->buffer[j] /= LRADC_DELAY_TIMER_LOOP;
+		j++;
+	}
+
+	iio_push_to_buffers_with_timestamp(iio, adc->buffer, pf->timestamp);
+
+	iio_trigger_notify_done(iio->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int mxs_lradc_adc_configure_trigger(struct iio_trigger *trig, bool state)
+{
+	struct iio_dev *iio = iio_trigger_get_drvdata(trig);
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	const u32 st = state ? STMP_OFFSET_REG_SET : STMP_OFFSET_REG_CLR;
+
+	mxs_lradc_reg_wrt(adc->lradc, LRADC_DELAY_KICK, LRADC_DELAY(0) + st);
+
+	return 0;
+}
+
+static const struct iio_trigger_ops mxs_lradc_adc_trigger_ops = {
+	.owner = THIS_MODULE,
+	.set_trigger_state = &mxs_lradc_adc_configure_trigger,
+};
+
+static int mxs_lradc_adc_trigger_init(struct iio_dev *iio)
+{
+	int ret;
+	struct iio_trigger *trig;
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+
+	trig = devm_iio_trigger_alloc(&iio->dev, "%s-dev%i", iio->name,
+				      iio->id);
+
+	trig->dev.parent = adc->dev;
+	iio_trigger_set_drvdata(trig, iio);
+	trig->ops = &mxs_lradc_adc_trigger_ops;
+
+	ret = iio_trigger_register(trig);
+	if (ret)
+		return ret;
+
+	adc->trig = trig;
+
+	return 0;
+}
+
+static void mxs_lradc_adc_trigger_remove(struct iio_dev *iio)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+
+	iio_trigger_unregister(adc->trig);
+}
+
+static int mxs_lradc_adc_buffer_preenable(struct iio_dev *iio)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	struct mxs_lradc *lradc = adc->lradc;
+	int chan, ofs = 0;
+	unsigned long enable = 0;
+	u32 ctrl4_set = 0;
+	u32 ctrl4_clr = 0;
+	u32 ctrl1_irq = 0;
+	const u32 chan_value = LRADC_CH_ACCUMULATE |
+		((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET);
+
+	if (lradc->soc == IMX28_LRADC)
+		mxs_lradc_reg_clear(lradc,
+			lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
+			LRADC_CTRL1);
+	mxs_lradc_reg_clear(lradc, lradc->buffer_vchans, LRADC_CTRL0);
+
+	for_each_set_bit(chan, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
+		ctrl4_set |= chan << LRADC_CTRL4_LRADCSELECT_OFFSET(ofs);
+		ctrl4_clr |= LRADC_CTRL4_LRADCSELECT_MASK(ofs);
+		ctrl1_irq |= LRADC_CTRL1_LRADC_IRQ_EN(ofs);
+		mxs_lradc_reg_wrt(lradc, chan_value, LRADC_CH(ofs));
+		bitmap_set(&enable, ofs, 1);
+		ofs++;
+	}
+
+	mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK |
+			    LRADC_DELAY_KICK, LRADC_DELAY(0));
+	mxs_lradc_reg_clear(lradc, ctrl4_clr, LRADC_CTRL4);
+	mxs_lradc_reg_set(lradc, ctrl4_set, LRADC_CTRL4);
+	mxs_lradc_reg_set(lradc, ctrl1_irq, LRADC_CTRL1);
+	mxs_lradc_reg_set(lradc, enable << LRADC_DELAY_TRIGGER_LRADCS_OFFSET,
+			  LRADC_DELAY(0));
+
+	return 0;
+}
+
+static int mxs_lradc_adc_buffer_postdisable(struct iio_dev *iio)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	struct mxs_lradc *lradc = adc->lradc;
+
+	mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK |
+			    LRADC_DELAY_KICK, LRADC_DELAY(0));
+
+	mxs_lradc_reg_clear(lradc, lradc->buffer_vchans, LRADC_CTRL0);
+	if (lradc->soc == IMX28_LRADC)
+		mxs_lradc_reg_clear(lradc,
+			lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
+			LRADC_CTRL1);
+
+	return 0;
+}
+
+static bool mxs_lradc_adc_validate_scan_mask(struct iio_dev *iio,
+					     const unsigned long *mask)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	struct mxs_lradc *lradc = adc->lradc;
+	const int map_chans = bitmap_weight(mask, LRADC_MAX_TOTAL_CHANS);
+	int rsvd_chans = 0;
+	unsigned long rsvd_mask = 0;
+
+	if (lradc->use_touchbutton)
+		rsvd_mask |= CHAN_MASK_TOUCHBUTTON;
+	if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_4WIRE)
+		rsvd_mask |= CHAN_MASK_TOUCHSCREEN_4WIRE;
+	if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE)
+		rsvd_mask |= CHAN_MASK_TOUCHSCREEN_5WIRE;
+
+	if (lradc->use_touchbutton)
+		rsvd_chans++;
+	if (lradc->use_touchscreen)
+		rsvd_chans += 2;
+
+	/* Test for attempts to map channels with special mode of operation. */
+	if (bitmap_intersects(mask, &rsvd_mask, LRADC_MAX_TOTAL_CHANS))
+		return false;
+
+	/* Test for attempts to map more channels then available slots. */
+	if (map_chans + rsvd_chans > LRADC_MAX_MAPPED_CHANS)
+		return false;
+
+	return true;
+}
+
+static const struct iio_buffer_setup_ops mxs_lradc_adc_buffer_ops = {
+	.preenable = &mxs_lradc_adc_buffer_preenable,
+	.postenable = &iio_triggered_buffer_postenable,
+	.predisable = &iio_triggered_buffer_predisable,
+	.postdisable = &mxs_lradc_adc_buffer_postdisable,
+	.validate_scan_mask = &mxs_lradc_adc_validate_scan_mask,
+};
+
+/* Driver initialization */
+#define MXS_ADC_CHAN(idx, chan_type, name) {			\
+	.type = (chan_type),					\
+	.indexed = 1,						\
+	.scan_index = (idx),					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
+			      BIT(IIO_CHAN_INFO_SCALE),		\
+	.channel = (idx),					\
+	.address = (idx),					\
+	.scan_type = {						\
+		.sign = 'u',					\
+		.realbits = LRADC_RESOLUTION,			\
+		.storagebits = 32,				\
+	},							\
+	.datasheet_name = (name),				\
+}
+
+static const struct iio_chan_spec mx23_lradc_chan_spec[] = {
+	MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"),
+	MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"),
+	MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"),
+	MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"),
+	MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"),
+	MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"),
+	MXS_ADC_CHAN(6, IIO_VOLTAGE, "VDDIO"),
+	MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"),
+	/* Combined Temperature sensors */
+	{
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.scan_index = 8,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_OFFSET) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+		.channel = 8,
+		.scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
+		.datasheet_name = "TEMP_DIE",
+	},
+	/* Hidden channel to keep indexes */
+	{
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.scan_index = -1,
+		.channel = 9,
+	},
+	MXS_ADC_CHAN(10, IIO_VOLTAGE, NULL),
+	MXS_ADC_CHAN(11, IIO_VOLTAGE, NULL),
+	MXS_ADC_CHAN(12, IIO_VOLTAGE, "USB_DP"),
+	MXS_ADC_CHAN(13, IIO_VOLTAGE, "USB_DN"),
+	MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"),
+	MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"),
+};
+
+static const struct iio_chan_spec mx28_lradc_chan_spec[] = {
+	MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"),
+	MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"),
+	MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"),
+	MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"),
+	MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"),
+	MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"),
+	MXS_ADC_CHAN(6, IIO_VOLTAGE, "LRADC6"),
+	MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"),
+	/* Combined Temperature sensors */
+	{
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.scan_index = 8,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_OFFSET) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+		.channel = 8,
+		.scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
+		.datasheet_name = "TEMP_DIE",
+	},
+	/* Hidden channel to keep indexes */
+	{
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.scan_index = -1,
+		.channel = 9,
+	},
+	MXS_ADC_CHAN(10, IIO_VOLTAGE, "VDDIO"),
+	MXS_ADC_CHAN(11, IIO_VOLTAGE, "VTH"),
+	MXS_ADC_CHAN(12, IIO_VOLTAGE, "VDDA"),
+	MXS_ADC_CHAN(13, IIO_VOLTAGE, "VDDD"),
+	MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"),
+	MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"),
+};
+
+static void mxs_lradc_adc_hw_init(struct mxs_lradc_adc *adc)
+{
+	struct mxs_lradc *lradc = adc->lradc;
+
+	/* The ADC always uses DELAY CHANNEL 0. */
+	const u32 adc_cfg =
+		(1 << (LRADC_DELAY_TRIGGER_DELAYS_OFFSET + 0)) |
+		(LRADC_DELAY_TIMER_PER << LRADC_DELAY_DELAY_OFFSET);
+
+	/* Configure DELAY CHANNEL 0 for generic ADC sampling. */
+	mxs_lradc_reg_wrt(lradc, adc_cfg, LRADC_DELAY(0));
+
+	/*
+	 * Start internal temperature sensing by clearing bit
+	 * HW_LRADC_CTRL2_TEMPSENSE_PWD. This bit can be left cleared
+	 * after power up.
+	 */
+	mxs_lradc_reg_wrt(lradc, 0, LRADC_CTRL2);
+}
+
+static void mxs_lradc_adc_hw_stop(struct mxs_lradc_adc *adc)
+{
+	mxs_lradc_reg_wrt(adc->lradc, 0, LRADC_DELAY(0));
+}
+
+static int mxs_lradc_adc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mxs_lradc *lradc = dev_get_platdata(dev);
+	struct mxs_lradc_adc *adc;
+	struct iio_dev *iio;
+	int ret, i, j, s, n;
+	u64 scale_uv;
+	const int *irq;
+
+	/* Allocate the IIO device. */
+	iio = devm_iio_device_alloc(dev, sizeof(*adc));
+	if (!iio) {
+		dev_err(dev, "Failed to allocate IIO device\n");
+		return -ENOMEM;
+	}
+
+	adc = iio_priv(iio);
+	adc->lradc = lradc;
+	adc->dev = dev;
+
+	init_completion(&adc->completion);
+	spin_lock_init(&adc->lock);
+
+	platform_set_drvdata(pdev, iio);
+
+	iio->name = pdev->name;
+	iio->dev.parent = dev;
+	iio->dev.of_node = dev->parent->of_node;
+	iio->info = &mxs_lradc_adc_iio_info;
+	iio->modes = INDIO_DIRECT_MODE;
+	iio->masklength = LRADC_MAX_TOTAL_CHANS;
+
+	if (lradc->soc == IMX23_LRADC) {
+		iio->channels = mx23_lradc_chan_spec;
+		iio->num_channels = ARRAY_SIZE(mx23_lradc_chan_spec);
+		irq = mx23_lradc_adc_irq;
+		n = IMX23_NUM_IRQ;
+	} else {
+		iio->channels = mx28_lradc_chan_spec;
+		iio->num_channels = ARRAY_SIZE(mx28_lradc_chan_spec);
+		irq = mx28_lradc_adc_irq;
+		n = IMX28_NUM_IRQ;
+	}
+
+	for (i = 0; i < n; i++) {
+		j = irq[i];
+		ret = devm_request_irq(dev, lradc->irq[j],
+				       mxs_lradc_adc_handle_irq,
+				       0, lradc->irq_name[j], iio);
+		if (ret)
+			return ret;
+	}
+
+	ret = mxs_lradc_adc_trigger_init(iio);
+	if (ret)
+		goto err_trig;
+
+	ret = iio_triggered_buffer_setup(iio, &iio_pollfunc_store_time,
+					 &mxs_lradc_adc_trigger_handler,
+					 &mxs_lradc_adc_buffer_ops);
+	if (ret)
+		return ret;
+
+	adc->vref_mv = mxs_lradc_adc_vref_mv[lradc->soc];
+
+	/* Populate available ADC input ranges */
+	for (i = 0; i < LRADC_MAX_TOTAL_CHANS; i++) {
+		for (s = 0; s < ARRAY_SIZE(adc->scale_avail[i]); s++) {
+			/*
+			 * [s=0] = optional divider by two disabled (default)
+			 * [s=1] = optional divider by two enabled
+			 *
+			 * The scale is calculated by doing:
+			 *   Vref >> (realbits - s)
+			 * which multiplies by two on the second component
+			 * of the array.
+			 */
+			scale_uv = ((u64)adc->vref_mv[i] * 100000000) >>
+				   (LRADC_RESOLUTION - s);
+			adc->scale_avail[i][s].nano =
+					do_div(scale_uv, 100000000) * 10;
+			adc->scale_avail[i][s].integer = scale_uv;
+		}
+	}
+
+	/* Configure the hardware. */
+	mxs_lradc_adc_hw_init(adc);
+
+	/* Register IIO device. */
+	ret = iio_device_register(iio);
+	if (ret) {
+		dev_err(dev, "Failed to register IIO device\n");
+		goto err_dev;
+	}
+
+	return 0;
+
+err_dev:
+	mxs_lradc_adc_hw_stop(adc);
+	mxs_lradc_adc_trigger_remove(iio);
+err_trig:
+	iio_triggered_buffer_cleanup(iio);
+	return ret;
+}
+
+static int mxs_lradc_adc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *iio = platform_get_drvdata(pdev);
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+
+	iio_device_unregister(iio);
+	mxs_lradc_adc_hw_stop(adc);
+	mxs_lradc_adc_trigger_remove(iio);
+	iio_triggered_buffer_cleanup(iio);
+
+	return 0;
+}
+
+static struct platform_driver mxs_lradc_adc_driver = {
+	.driver = {
+		.name	= DRIVER_NAME_ADC,
+	},
+	.probe	= mxs_lradc_adc_probe,
+	.remove = mxs_lradc_adc_remove,
+};
+
+module_platform_driver(mxs_lradc_adc_driver);
+
+MODULE_AUTHOR("Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>");
+MODULE_DESCRIPTION("Freescale MXS LRADC driver general purpose ADC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME_ADC);
-- 
1.9.1

[PATCH v3 2/4] iio: adc: mxs-lradc: Add support for adc driver

[Ksenija Stanojevic]

Add support for sixteen-channel 12-bit resolution ADC and its functions,
which include general-purpose ADC readings, battery voltage measurement,
and die temperature measurement.

Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
---
Changes in v3:
 - make buffer large enough for timestamps
 - remove unnecessary blank lines

Changes in v2:
 - improve commit message
 - do not change spacing in Kconfig
 - impove formating
 - remove wrapper show_scale_avail
 - use correct syntax for comments
 - use devm_iio_trigger_alloc
 - do not allocate buffer dynamically 
 - use iio_device_claim_*_mode helpers
 - add spinlock in struct mxs_lradc_ts to enable locking in interrupt handler
 - only grab irqs that are relevant to adc
 - remove blank line at the end of the file
 - change licence to GPL
 - add copyright

 drivers/iio/adc/Kconfig         |  13 +
 drivers/iio/adc/Makefile        |   1 +
 drivers/iio/adc/mxs-lradc-adc.c | 811 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 825 insertions(+)
 create mode 100644 drivers/iio/adc/mxs-lradc-adc.c

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 932de1f..4ef3ad1 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -194,6 +194,19 @@ config EXYNOS_ADC
 	  To compile this driver as a module, choose M here: the module will be
 	  called exynos_adc.
 
+config MXS_LRADC_ADC
+	tristate "Freescale i.MX23/i.MX28 LRADC ADC"
+	depends on MFD_MXS_LRADC
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	  Say yes here to build support for the ADC functions of the
+	  i.MX23/i.MX28 LRADC. This includes general-purpose ADC readings,
+	  battery voltage measurement, and die temperature measurement.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called mxs-lradc-adc.
+
 config HI8435
 	tristate "Holt Integrated Circuits HI-8435 threshold detector"
 	select IIO_TRIGGERED_EVENT
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index b1aa456..9bb35c4 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_MAX1363) += max1363.o
 obj-$(CONFIG_MCP320X) += mcp320x.o
 obj-$(CONFIG_MCP3422) += mcp3422.o
 obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o
+obj-$(CONFIG_MXS_LRADC_ADC) += mxs-lradc-adc.o
 obj-$(CONFIG_MXS_LRADC) += mxs-lradc.o
 obj-$(CONFIG_NAU7802) += nau7802.o
 obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o
diff --git a/drivers/iio/adc/mxs-lradc-adc.c b/drivers/iio/adc/mxs-lradc-adc.c
new file mode 100644
index 0000000..9d33fe3
--- /dev/null
+++ b/drivers/iio/adc/mxs-lradc-adc.c
@@ -0,0 +1,811 @@
+/*
+ * Freescale MXS LRADC ADC driver
+ *
+ * Copyright (c) 2012 DENX Software Engineering, GmbH.
+ * Marek Vasut <marex@denx.de>
+ * Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/mxs-lradc.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/sysfs.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/sysfs.h>
+
+/*
+ * Make this runtime configurable if necessary. Currently, if the buffered mode
+ * is enabled, the LRADC takes LRADC_DELAY_TIMER_LOOP samples of data before
+ * triggering IRQ. The sampling happens every (LRADC_DELAY_TIMER_PER / 2000)
+ * seconds. The result is that the samples arrive every 500mS.
+ */
+#define LRADC_DELAY_TIMER_PER	200
+#define LRADC_DELAY_TIMER_LOOP	5
+
+#define VREF_MV_BASE 1850
+
+#define IMX23_NUM_IRQ 6
+#define IMX28_NUM_IRQ 10
+
+static const int mx23_lradc_adc_irq[] = {1, 2, 3, 4, 5, 6};
+static const int mx28_lradc_adc_irq[] = {1, 2, 3, 4, 5, 6, 7, 8, 11, 12};
+
+static const u32 mxs_lradc_adc_vref_mv[][LRADC_MAX_TOTAL_CHANS] = {
+	[IMX23_LRADC] = {
+		VREF_MV_BASE,		/* CH0 */
+		VREF_MV_BASE,		/* CH1 */
+		VREF_MV_BASE,		/* CH2 */
+		VREF_MV_BASE,		/* CH3 */
+		VREF_MV_BASE,		/* CH4 */
+		VREF_MV_BASE,		/* CH5 */
+		VREF_MV_BASE * 2,	/* CH6 VDDIO */
+		VREF_MV_BASE * 4,	/* CH7 VBATT */
+		VREF_MV_BASE,		/* CH8 Temp sense 0 */
+		VREF_MV_BASE,		/* CH9 Temp sense 1 */
+		VREF_MV_BASE,		/* CH10 */
+		VREF_MV_BASE,		/* CH11 */
+		VREF_MV_BASE,		/* CH12 USB_DP */
+		VREF_MV_BASE,		/* CH13 USB_DN */
+		VREF_MV_BASE,		/* CH14 VBG */
+		VREF_MV_BASE * 4,	/* CH15 VDD5V */
+	},
+	[IMX28_LRADC] = {
+		VREF_MV_BASE,		/* CH0 */
+		VREF_MV_BASE,		/* CH1 */
+		VREF_MV_BASE,		/* CH2 */
+		VREF_MV_BASE,		/* CH3 */
+		VREF_MV_BASE,		/* CH4 */
+		VREF_MV_BASE,		/* CH5 */
+		VREF_MV_BASE,		/* CH6 */
+		VREF_MV_BASE * 4,	/* CH7 VBATT */
+		VREF_MV_BASE,		/* CH8 Temp sense 0 */
+		VREF_MV_BASE,		/* CH9 Temp sense 1 */
+		VREF_MV_BASE * 2,	/* CH10 VDDIO */
+		VREF_MV_BASE,		/* CH11 VTH */
+		VREF_MV_BASE * 2,	/* CH12 VDDA */
+		VREF_MV_BASE,		/* CH13 VDDD */
+		VREF_MV_BASE,		/* CH14 VBG */
+		VREF_MV_BASE * 4,	/* CH15 VDD5V */
+	},
+};
+
+enum mxs_lradc_divbytwo {
+	MXS_LRADC_DIV_DISABLED = 0,
+	MXS_LRADC_DIV_ENABLED,
+};
+
+struct mxs_lradc_scale {
+	unsigned int		integer;
+	unsigned int		nano;
+};
+
+struct mxs_lradc_adc {
+	struct mxs_lradc	*lradc;
+	struct device		*dev;
+
+	u32			buffer[10];
+	struct iio_trigger	*trig;
+	struct completion	completion;
+	spinlock_t		lock;
+
+	const u32		*vref_mv;
+	struct mxs_lradc_scale	scale_avail[LRADC_MAX_TOTAL_CHANS][2];
+	unsigned long		is_divided;
+};
+
+
+/* Raw I/O operations */
+static int mxs_lradc_adc_read_single(struct iio_dev *iio_dev, int chan,
+				     int *val)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio_dev);
+	struct mxs_lradc *lradc = adc->lradc;
+	int ret;
+
+	/*
+	 * See if there is no buffered operation in progress. If there is simply
+	 * bail out. This can be improved to support both buffered and raw IO at
+	 * the same time, yet the code becomes horribly complicated. Therefore I
+	 * applied KISS principle here.
+	 */
+	ret = iio_device_claim_direct_mode(iio_dev);
+	if (ret)
+		return ret;
+
+	reinit_completion(&adc->completion);
+
+	/*
+	 * No buffered operation in progress, map the channel and trigger it.
+	 * Virtual channel 0 is always used here as the others are always not
+	 * used if doing raw sampling.
+	 */
+	if (lradc->soc == IMX28_LRADC)
+		mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0),
+				    LRADC_CTRL1);
+	mxs_lradc_reg_clear(lradc, 0x1, LRADC_CTRL0);
+
+	/* Enable / disable the divider per requirement */
+	if (test_bit(chan, &adc->is_divided))
+		mxs_lradc_reg_set(lradc,
+				  1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
+				  LRADC_CTRL2);
+	else
+		mxs_lradc_reg_clear(lradc,
+				    1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
+				    LRADC_CTRL2);
+
+	/* Clean the slot's previous content, then set new one. */
+	mxs_lradc_reg_clear(lradc, LRADC_CTRL4_LRADCSELECT_MASK(0),
+			    LRADC_CTRL4);
+	mxs_lradc_reg_set(lradc, chan, LRADC_CTRL4);
+
+	mxs_lradc_reg_wrt(lradc, 0, LRADC_CH(0));
+
+	/* Enable the IRQ and start sampling the channel. */
+	mxs_lradc_reg_set(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1);
+	mxs_lradc_reg_set(lradc, BIT(0), LRADC_CTRL0);
+
+	/* Wait for completion on the channel, 1 second max. */
+	ret = wait_for_completion_killable_timeout(&adc->completion, HZ);
+	if (!ret)
+		ret = -ETIMEDOUT;
+	if (ret < 0)
+		goto err;
+
+	/* Read the data. */
+	*val = readl(lradc->base + LRADC_CH(0)) & LRADC_CH_VALUE_MASK;
+	ret = IIO_VAL_INT;
+
+err:
+	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1);
+
+	iio_device_release_direct_mode(iio_dev);
+
+	return ret;
+}
+
+static int mxs_lradc_adc_read_temp(struct iio_dev *iio_dev, int *val)
+{
+	int ret, min, max;
+
+	ret = mxs_lradc_adc_read_single(iio_dev, 8, &min);
+	if (ret != IIO_VAL_INT)
+		return ret;
+
+	ret = mxs_lradc_adc_read_single(iio_dev, 9, &max);
+	if (ret != IIO_VAL_INT)
+		return ret;
+
+	*val = max - min;
+
+	return IIO_VAL_INT;
+}
+
+static int mxs_lradc_adc_read_raw(struct iio_dev *iio_dev,
+			      const struct iio_chan_spec *chan,
+			      int *val, int *val2, long m)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio_dev);
+
+	switch (m) {
+	case IIO_CHAN_INFO_RAW:
+		if (chan->type == IIO_TEMP)
+			return mxs_lradc_adc_read_temp(iio_dev, val);
+
+		return mxs_lradc_adc_read_single(iio_dev, chan->channel, val);
+
+	case IIO_CHAN_INFO_SCALE:
+		if (chan->type == IIO_TEMP) {
+			/*
+			 * From the datasheet, we have to multiply by 1.012 and
+			 * divide by 4
+			 */
+			*val = 0;
+			*val2 = 253000;
+			return IIO_VAL_INT_PLUS_MICRO;
+		}
+
+		*val = adc->vref_mv[chan->channel];
+		*val2 = chan->scan_type.realbits -
+			test_bit(chan->channel, &adc->is_divided);
+		return IIO_VAL_FRACTIONAL_LOG2;
+
+	case IIO_CHAN_INFO_OFFSET:
+		if (chan->type == IIO_TEMP) {
+			/*
+			 * The calculated value from the ADC is in Kelvin, we
+			 * want Celsius for hwmon so the offset is -273.15
+			 * The offset is applied before scaling so it is
+			 * actually -213.15 * 4 / 1.012 = -1079.644268
+			 */
+			*val = -1079;
+			*val2 = 644268;
+
+			return IIO_VAL_INT_PLUS_MICRO;
+		}
+
+		return -EINVAL;
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int mxs_lradc_adc_write_raw(struct iio_dev *iio_dev,
+				   const struct iio_chan_spec *chan,
+				   int val, int val2, long m)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio_dev);
+	struct mxs_lradc_scale *scale_avail =
+			adc->scale_avail[chan->channel];
+	int ret;
+
+	ret = iio_device_claim_direct_mode(iio_dev);
+	if (ret)
+		return ret;
+
+	switch (m) {
+	case IIO_CHAN_INFO_SCALE:
+		ret = -EINVAL;
+		if (val == scale_avail[MXS_LRADC_DIV_DISABLED].integer &&
+		    val2 == scale_avail[MXS_LRADC_DIV_DISABLED].nano) {
+			/* divider by two disabled */
+			clear_bit(chan->channel, &adc->is_divided);
+			ret = 0;
+		} else if (val == scale_avail[MXS_LRADC_DIV_ENABLED].integer &&
+			   val2 == scale_avail[MXS_LRADC_DIV_ENABLED].nano) {
+			/* divider by two enabled */
+			set_bit(chan->channel, &adc->is_divided);
+			ret = 0;
+		}
+
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	iio_device_release_direct_mode(iio_dev);
+
+	return ret;
+}
+
+static int mxs_lradc_adc_write_raw_get_fmt(struct iio_dev *iio_dev,
+					   const struct iio_chan_spec *chan,
+					   long m)
+{
+	return IIO_VAL_INT_PLUS_NANO;
+}
+
+static ssize_t mxs_lradc_adc_show_scale_avail(struct device *dev,
+						 struct device_attribute *attr,
+						 char *buf)
+{
+	struct iio_dev *iio = dev_to_iio_dev(dev);
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	struct iio_dev_attr *iio_attr = to_iio_dev_attr(attr);
+	int i, ch, len = 0;
+
+	ch = iio_attr->address;
+	for (i = 0; i < ARRAY_SIZE(adc->scale_avail[ch]); i++)
+		len += sprintf(buf + len, "%u.%09u ",
+			       adc->scale_avail[ch][i].integer,
+			       adc->scale_avail[ch][i].nano);
+
+	len += sprintf(buf + len, "\n");
+
+	return len;
+}
+
+#define SHOW_SCALE_AVAILABLE_ATTR(ch)					\
+static IIO_DEVICE_ATTR(in_voltage##ch##_scale_available, S_IRUGO,	\
+		       mxs_lradc_adc_show_scale_avail, NULL, ch)
+
+SHOW_SCALE_AVAILABLE_ATTR(0);
+SHOW_SCALE_AVAILABLE_ATTR(1);
+SHOW_SCALE_AVAILABLE_ATTR(2);
+SHOW_SCALE_AVAILABLE_ATTR(3);
+SHOW_SCALE_AVAILABLE_ATTR(4);
+SHOW_SCALE_AVAILABLE_ATTR(5);
+SHOW_SCALE_AVAILABLE_ATTR(6);
+SHOW_SCALE_AVAILABLE_ATTR(7);
+SHOW_SCALE_AVAILABLE_ATTR(10);
+SHOW_SCALE_AVAILABLE_ATTR(11);
+SHOW_SCALE_AVAILABLE_ATTR(12);
+SHOW_SCALE_AVAILABLE_ATTR(13);
+SHOW_SCALE_AVAILABLE_ATTR(14);
+SHOW_SCALE_AVAILABLE_ATTR(15);
+
+static struct attribute *mxs_lradc_adc_attributes[] = {
+	&iio_dev_attr_in_voltage0_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage1_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage2_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage3_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage4_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage5_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage6_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage7_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage10_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage11_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage12_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage13_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage14_scale_available.dev_attr.attr,
+	&iio_dev_attr_in_voltage15_scale_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group mxs_lradc_adc_attribute_group = {
+	.attrs = mxs_lradc_adc_attributes,
+};
+
+static const struct iio_info mxs_lradc_adc_iio_info = {
+	.driver_module		= THIS_MODULE,
+	.read_raw		= mxs_lradc_adc_read_raw,
+	.write_raw		= mxs_lradc_adc_write_raw,
+	.write_raw_get_fmt	= mxs_lradc_adc_write_raw_get_fmt,
+	.attrs			= &mxs_lradc_adc_attribute_group,
+};
+
+/* IRQ Handling */
+static irqreturn_t mxs_lradc_adc_handle_irq(int irq, void *data)
+{
+	struct iio_dev *iio = data;
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	struct mxs_lradc *lradc = adc->lradc;
+	unsigned long reg = readl(lradc->base + LRADC_CTRL1);
+	unsigned long flags;
+
+	if (!(reg & mxs_lradc_irq_mask(lradc)))
+		return IRQ_NONE;
+
+	if (iio_buffer_enabled(iio)) {
+		if (reg & lradc->buffer_vchans) {
+			spin_lock_irqsave(&adc->lock, flags);
+			iio_trigger_poll(iio->trig);
+			spin_unlock_irqrestore(&adc->lock, flags);
+		}
+	} else if (reg & LRADC_CTRL1_LRADC_IRQ(0)) {
+		complete(&adc->completion);
+	}
+
+	mxs_lradc_reg_clear(lradc, reg & mxs_lradc_irq_mask(lradc),
+			    LRADC_CTRL1);
+
+	return IRQ_HANDLED;
+}
+
+
+/* Trigger handling */
+static irqreturn_t mxs_lradc_adc_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *iio = pf->indio_dev;
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	const u32 chan_value = LRADC_CH_ACCUMULATE |
+		((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET);
+	unsigned int i, j = 0;
+
+	for_each_set_bit(i, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
+		adc->buffer[j] = readl(adc->lradc->base + LRADC_CH(j));
+		mxs_lradc_reg_wrt(adc->lradc, chan_value, LRADC_CH(j));
+		adc->buffer[j] &= LRADC_CH_VALUE_MASK;
+		adc->buffer[j] /= LRADC_DELAY_TIMER_LOOP;
+		j++;
+	}
+
+	iio_push_to_buffers_with_timestamp(iio, adc->buffer, pf->timestamp);
+
+	iio_trigger_notify_done(iio->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int mxs_lradc_adc_configure_trigger(struct iio_trigger *trig, bool state)
+{
+	struct iio_dev *iio = iio_trigger_get_drvdata(trig);
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	const u32 st = state ? STMP_OFFSET_REG_SET : STMP_OFFSET_REG_CLR;
+
+	mxs_lradc_reg_wrt(adc->lradc, LRADC_DELAY_KICK, LRADC_DELAY(0) + st);
+
+	return 0;
+}
+
+static const struct iio_trigger_ops mxs_lradc_adc_trigger_ops = {
+	.owner = THIS_MODULE,
+	.set_trigger_state = &mxs_lradc_adc_configure_trigger,
+};
+
+static int mxs_lradc_adc_trigger_init(struct iio_dev *iio)
+{
+	int ret;
+	struct iio_trigger *trig;
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+
+	trig = devm_iio_trigger_alloc(&iio->dev, "%s-dev%i", iio->name,
+				      iio->id);
+
+	trig->dev.parent = adc->dev;
+	iio_trigger_set_drvdata(trig, iio);
+	trig->ops = &mxs_lradc_adc_trigger_ops;
+
+	ret = iio_trigger_register(trig);
+	if (ret)
+		return ret;
+
+	adc->trig = trig;
+
+	return 0;
+}
+
+static void mxs_lradc_adc_trigger_remove(struct iio_dev *iio)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+
+	iio_trigger_unregister(adc->trig);
+}
+
+static int mxs_lradc_adc_buffer_preenable(struct iio_dev *iio)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	struct mxs_lradc *lradc = adc->lradc;
+	int chan, ofs = 0;
+	unsigned long enable = 0;
+	u32 ctrl4_set = 0;
+	u32 ctrl4_clr = 0;
+	u32 ctrl1_irq = 0;
+	const u32 chan_value = LRADC_CH_ACCUMULATE |
+		((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET);
+
+	if (lradc->soc == IMX28_LRADC)
+		mxs_lradc_reg_clear(lradc,
+			lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
+			LRADC_CTRL1);
+	mxs_lradc_reg_clear(lradc, lradc->buffer_vchans, LRADC_CTRL0);
+
+	for_each_set_bit(chan, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
+		ctrl4_set |= chan << LRADC_CTRL4_LRADCSELECT_OFFSET(ofs);
+		ctrl4_clr |= LRADC_CTRL4_LRADCSELECT_MASK(ofs);
+		ctrl1_irq |= LRADC_CTRL1_LRADC_IRQ_EN(ofs);
+		mxs_lradc_reg_wrt(lradc, chan_value, LRADC_CH(ofs));
+		bitmap_set(&enable, ofs, 1);
+		ofs++;
+	}
+
+	mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK |
+			    LRADC_DELAY_KICK, LRADC_DELAY(0));
+	mxs_lradc_reg_clear(lradc, ctrl4_clr, LRADC_CTRL4);
+	mxs_lradc_reg_set(lradc, ctrl4_set, LRADC_CTRL4);
+	mxs_lradc_reg_set(lradc, ctrl1_irq, LRADC_CTRL1);
+	mxs_lradc_reg_set(lradc, enable << LRADC_DELAY_TRIGGER_LRADCS_OFFSET,
+			  LRADC_DELAY(0));
+
+	return 0;
+}
+
+static int mxs_lradc_adc_buffer_postdisable(struct iio_dev *iio)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	struct mxs_lradc *lradc = adc->lradc;
+
+	mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK |
+			    LRADC_DELAY_KICK, LRADC_DELAY(0));
+
+	mxs_lradc_reg_clear(lradc, lradc->buffer_vchans, LRADC_CTRL0);
+	if (lradc->soc == IMX28_LRADC)
+		mxs_lradc_reg_clear(lradc,
+			lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
+			LRADC_CTRL1);
+
+	return 0;
+}
+
+static bool mxs_lradc_adc_validate_scan_mask(struct iio_dev *iio,
+					     const unsigned long *mask)
+{
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+	struct mxs_lradc *lradc = adc->lradc;
+	const int map_chans = bitmap_weight(mask, LRADC_MAX_TOTAL_CHANS);
+	int rsvd_chans = 0;
+	unsigned long rsvd_mask = 0;
+
+	if (lradc->use_touchbutton)
+		rsvd_mask |= CHAN_MASK_TOUCHBUTTON;
+	if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_4WIRE)
+		rsvd_mask |= CHAN_MASK_TOUCHSCREEN_4WIRE;
+	if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE)
+		rsvd_mask |= CHAN_MASK_TOUCHSCREEN_5WIRE;
+
+	if (lradc->use_touchbutton)
+		rsvd_chans++;
+	if (lradc->use_touchscreen)
+		rsvd_chans += 2;
+
+	/* Test for attempts to map channels with special mode of operation. */
+	if (bitmap_intersects(mask, &rsvd_mask, LRADC_MAX_TOTAL_CHANS))
+		return false;
+
+	/* Test for attempts to map more channels then available slots. */
+	if (map_chans + rsvd_chans > LRADC_MAX_MAPPED_CHANS)
+		return false;
+
+	return true;
+}
+
+static const struct iio_buffer_setup_ops mxs_lradc_adc_buffer_ops = {
+	.preenable = &mxs_lradc_adc_buffer_preenable,
+	.postenable = &iio_triggered_buffer_postenable,
+	.predisable = &iio_triggered_buffer_predisable,
+	.postdisable = &mxs_lradc_adc_buffer_postdisable,
+	.validate_scan_mask = &mxs_lradc_adc_validate_scan_mask,
+};
+
+/* Driver initialization */
+#define MXS_ADC_CHAN(idx, chan_type, name) {			\
+	.type = (chan_type),					\
+	.indexed = 1,						\
+	.scan_index = (idx),					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
+			      BIT(IIO_CHAN_INFO_SCALE),		\
+	.channel = (idx),					\
+	.address = (idx),					\
+	.scan_type = {						\
+		.sign = 'u',					\
+		.realbits = LRADC_RESOLUTION,			\
+		.storagebits = 32,				\
+	},							\
+	.datasheet_name = (name),				\
+}
+
+static const struct iio_chan_spec mx23_lradc_chan_spec[] = {
+	MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"),
+	MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"),
+	MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"),
+	MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"),
+	MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"),
+	MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"),
+	MXS_ADC_CHAN(6, IIO_VOLTAGE, "VDDIO"),
+	MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"),
+	/* Combined Temperature sensors */
+	{
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.scan_index = 8,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_OFFSET) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+		.channel = 8,
+		.scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
+		.datasheet_name = "TEMP_DIE",
+	},
+	/* Hidden channel to keep indexes */
+	{
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.scan_index = -1,
+		.channel = 9,
+	},
+	MXS_ADC_CHAN(10, IIO_VOLTAGE, NULL),
+	MXS_ADC_CHAN(11, IIO_VOLTAGE, NULL),
+	MXS_ADC_CHAN(12, IIO_VOLTAGE, "USB_DP"),
+	MXS_ADC_CHAN(13, IIO_VOLTAGE, "USB_DN"),
+	MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"),
+	MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"),
+};
+
+static const struct iio_chan_spec mx28_lradc_chan_spec[] = {
+	MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"),
+	MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"),
+	MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"),
+	MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"),
+	MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"),
+	MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"),
+	MXS_ADC_CHAN(6, IIO_VOLTAGE, "LRADC6"),
+	MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"),
+	/* Combined Temperature sensors */
+	{
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.scan_index = 8,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_OFFSET) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+		.channel = 8,
+		.scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
+		.datasheet_name = "TEMP_DIE",
+	},
+	/* Hidden channel to keep indexes */
+	{
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.scan_index = -1,
+		.channel = 9,
+	},
+	MXS_ADC_CHAN(10, IIO_VOLTAGE, "VDDIO"),
+	MXS_ADC_CHAN(11, IIO_VOLTAGE, "VTH"),
+	MXS_ADC_CHAN(12, IIO_VOLTAGE, "VDDA"),
+	MXS_ADC_CHAN(13, IIO_VOLTAGE, "VDDD"),
+	MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"),
+	MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"),
+};
+
+static void mxs_lradc_adc_hw_init(struct mxs_lradc_adc *adc)
+{
+	struct mxs_lradc *lradc = adc->lradc;
+
+	/* The ADC always uses DELAY CHANNEL 0. */
+	const u32 adc_cfg =
+		(1 << (LRADC_DELAY_TRIGGER_DELAYS_OFFSET + 0)) |
+		(LRADC_DELAY_TIMER_PER << LRADC_DELAY_DELAY_OFFSET);
+
+	/* Configure DELAY CHANNEL 0 for generic ADC sampling. */
+	mxs_lradc_reg_wrt(lradc, adc_cfg, LRADC_DELAY(0));
+
+	/*
+	 * Start internal temperature sensing by clearing bit
+	 * HW_LRADC_CTRL2_TEMPSENSE_PWD. This bit can be left cleared
+	 * after power up.
+	 */
+	mxs_lradc_reg_wrt(lradc, 0, LRADC_CTRL2);
+}
+
+static void mxs_lradc_adc_hw_stop(struct mxs_lradc_adc *adc)
+{
+	mxs_lradc_reg_wrt(adc->lradc, 0, LRADC_DELAY(0));
+}
+
+static int mxs_lradc_adc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mxs_lradc *lradc = dev_get_platdata(dev);
+	struct mxs_lradc_adc *adc;
+	struct iio_dev *iio;
+	int ret, i, j, s, n;
+	u64 scale_uv;
+	const int *irq;
+
+	/* Allocate the IIO device. */
+	iio = devm_iio_device_alloc(dev, sizeof(*adc));
+	if (!iio) {
+		dev_err(dev, "Failed to allocate IIO device\n");
+		return -ENOMEM;
+	}
+
+	adc = iio_priv(iio);
+	adc->lradc = lradc;
+	adc->dev = dev;
+
+	init_completion(&adc->completion);
+	spin_lock_init(&adc->lock);
+
+	platform_set_drvdata(pdev, iio);
+
+	iio->name = pdev->name;
+	iio->dev.parent = dev;
+	iio->dev.of_node = dev->parent->of_node;
+	iio->info = &mxs_lradc_adc_iio_info;
+	iio->modes = INDIO_DIRECT_MODE;
+	iio->masklength = LRADC_MAX_TOTAL_CHANS;
+
+	if (lradc->soc == IMX23_LRADC) {
+		iio->channels = mx23_lradc_chan_spec;
+		iio->num_channels = ARRAY_SIZE(mx23_lradc_chan_spec);
+		irq = mx23_lradc_adc_irq;
+		n = IMX23_NUM_IRQ;
+	} else {
+		iio->channels = mx28_lradc_chan_spec;
+		iio->num_channels = ARRAY_SIZE(mx28_lradc_chan_spec);
+		irq = mx28_lradc_adc_irq;
+		n = IMX28_NUM_IRQ;
+	}
+
+	for (i = 0; i < n; i++) {
+		j = irq[i];
+		ret = devm_request_irq(dev, lradc->irq[j],
+				       mxs_lradc_adc_handle_irq,
+				       0, lradc->irq_name[j], iio);
+		if (ret)
+			return ret;
+	}
+
+	ret = mxs_lradc_adc_trigger_init(iio);
+	if (ret)
+		goto err_trig;
+
+	ret = iio_triggered_buffer_setup(iio, &iio_pollfunc_store_time,
+					 &mxs_lradc_adc_trigger_handler,
+					 &mxs_lradc_adc_buffer_ops);
+	if (ret)
+		return ret;
+
+	adc->vref_mv = mxs_lradc_adc_vref_mv[lradc->soc];
+
+	/* Populate available ADC input ranges */
+	for (i = 0; i < LRADC_MAX_TOTAL_CHANS; i++) {
+		for (s = 0; s < ARRAY_SIZE(adc->scale_avail[i]); s++) {
+			/*
+			 * [s=0] = optional divider by two disabled (default)
+			 * [s=1] = optional divider by two enabled
+			 *
+			 * The scale is calculated by doing:
+			 *   Vref >> (realbits - s)
+			 * which multiplies by two on the second component
+			 * of the array.
+			 */
+			scale_uv = ((u64)adc->vref_mv[i] * 100000000) >>
+				   (LRADC_RESOLUTION - s);
+			adc->scale_avail[i][s].nano =
+					do_div(scale_uv, 100000000) * 10;
+			adc->scale_avail[i][s].integer = scale_uv;
+		}
+	}
+
+	/* Configure the hardware. */
+	mxs_lradc_adc_hw_init(adc);
+
+	/* Register IIO device. */
+	ret = iio_device_register(iio);
+	if (ret) {
+		dev_err(dev, "Failed to register IIO device\n");
+		goto err_dev;
+	}
+
+	return 0;
+
+err_dev:
+	mxs_lradc_adc_hw_stop(adc);
+	mxs_lradc_adc_trigger_remove(iio);
+err_trig:
+	iio_triggered_buffer_cleanup(iio);
+	return ret;
+}
+
+static int mxs_lradc_adc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *iio = platform_get_drvdata(pdev);
+	struct mxs_lradc_adc *adc = iio_priv(iio);
+
+	iio_device_unregister(iio);
+	mxs_lradc_adc_hw_stop(adc);
+	mxs_lradc_adc_trigger_remove(iio);
+	iio_triggered_buffer_cleanup(iio);
+
+	return 0;
+}
+
+static struct platform_driver mxs_lradc_adc_driver = {
+	.driver = {
+		.name	= DRIVER_NAME_ADC,
+	},
+	.probe	= mxs_lradc_adc_probe,
+	.remove = mxs_lradc_adc_remove,
+};
+
+module_platform_driver(mxs_lradc_adc_driver);
+
+MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
+MODULE_DESCRIPTION("Freescale MXS LRADC driver general purpose ADC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME_ADC);
-- 
1.9.1

Re: [PATCH v3 2/4] iio: adc: mxs-lradc: Add support for adc driver

[Stefan Wahren]

> Ksenija Stanojevic <ksenija.stanojevic@gmail.com> hat am 24. Juni 2016 um
> 14:10 geschrieben:
> 
> 
> Add support for sixteen-channel 12-bit resolution ADC and its functions,
> which include general-purpose ADC readings, battery voltage measurement,
> and die temperature measurement.
> 
> Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
> Acked-by: Jonathan Cameron <jic23@kernel.org>

Tested-by: Stefan Wahren <stefan.wahren@i2se.com>

Thanks a lot

[PATCH v3 3/4] input: touchscreen: mxs-lradc: Add support for touchscreen

[Ksenija Stanojevic]

Add 4-wire/5-wire touchscreen controller.

Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
Changes in v3:
 - add MODULE_*(ALIAS, AUTHOR, DESCRIPTION)

Changes in v2:
 - do not change spacing in Kconfig
 - remove dev.parent
 - rename err_ts_register to error
 - combine functions hw_stop and disable_ts so that mxs_lradc_ts_remove
   could be deleted.
 - add spinlock in struct mxs_lradc_ts to enable locking in interrupt handler.
 - only grab irqs that are relevant to touchscreen
 - use direct return instead assigning error to touch_ret in probe function.
 - change licence to GPL
 - add copyright

 drivers/input/touchscreen/Kconfig        |  10 +
 drivers/input/touchscreen/Makefile       |   1 +
 drivers/input/touchscreen/mxs-lradc-ts.c | 729 +++++++++++++++++++++++++++++++
 3 files changed, 740 insertions(+)
 create mode 100644 drivers/input/touchscreen/mxs-lradc-ts.c

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 66c6264..a34661d 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -305,6 +305,16 @@ config TOUCHSCREEN_EGALAX_SERIAL
 	  To compile this driver as a module, choose M here: the
 	  module will be called egalax_ts_serial.
 
+config TOUCHSCREEN_MXS_LRADC
+	tristate "Freescale i.MX23/i.MX28 LRADC touchscreen"
+	depends on MFD_MXS_LRADC
+	help
+	  Say Y here if you have a touchscreen connected to the low-resolution
+	  analog-to-digital converter (LRADC) on an i.MX23 or i.MX28 processor.
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called mxs-lradc-ts.
+
 config TOUCHSCREEN_FT6236
 	tristate "FT6236 I2C touchscreen"
 	depends on I2C
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 968ff12..6319b5c 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_TOUCHSCREEN_MIGOR)		+= migor_ts.o
 obj-$(CONFIG_TOUCHSCREEN_MMS114)	+= mms114.o
 obj-$(CONFIG_TOUCHSCREEN_MTOUCH)	+= mtouch.o
 obj-$(CONFIG_TOUCHSCREEN_MK712)		+= mk712.o
+obj-$(CONFIG_TOUCHSCREEN_MXS_LRADC)	+= mxs-lradc-ts.o
 obj-$(CONFIG_TOUCHSCREEN_HP600)		+= hp680_ts_input.o
 obj-$(CONFIG_TOUCHSCREEN_HP7XX)		+= jornada720_ts.o
 obj-$(CONFIG_TOUCHSCREEN_IPAQ_MICRO)	+= ipaq-micro-ts.o
diff --git a/drivers/input/touchscreen/mxs-lradc-ts.c b/drivers/input/touchscreen/mxs-lradc-ts.c
new file mode 100644
index 0000000..7a776c1
--- /dev/null
+++ b/drivers/input/touchscreen/mxs-lradc-ts.c
@@ -0,0 +1,729 @@
+/*
+ * Freescale MXS LRADC touchscreen driver
+ *
+ * Copyright (c) 2012 DENX Software Engineering, GmbH.
+ * Marek Vasut <marex@denx.de>
+ * Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/mxs-lradc.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+static const int mxs_lradc_ts_irq[][3] = {
+	[IMX23_LRADC] = {0, 7, 8},
+	[IMX28_LRADC] = {0, 9, 10},
+};
+
+/*
+ * Touchscreen handling
+ */
+enum mxs_lradc_ts_plate {
+	LRADC_TOUCH = 0,
+	LRADC_SAMPLE_X,
+	LRADC_SAMPLE_Y,
+	LRADC_SAMPLE_PRESSURE,
+	LRADC_SAMPLE_VALID,
+};
+
+struct mxs_lradc_ts {
+	struct mxs_lradc	*lradc;
+	struct device		*dev;
+	/*
+	 * When the touchscreen is enabled, we give it two private virtual
+	 * channels: #6 and #7. This means that only 6 virtual channels (instead
+	 * of 8) will be available for buffered capture.
+	 */
+#define TOUCHSCREEN_VCHANNEL1		7
+#define TOUCHSCREEN_VCHANNEL2		6
+
+	struct input_dev	*ts_input;
+
+	enum mxs_lradc_ts_plate	cur_plate; /* state machine */
+	bool			ts_valid;
+	unsigned int		ts_x_pos;
+	unsigned int		ts_y_pos;
+	unsigned int		ts_pressure;
+
+	/* handle touchscreen's physical behaviour */
+	/* samples per coordinate */
+	unsigned int		over_sample_cnt;
+	/* time clocks between samples */
+	unsigned int		over_sample_delay;
+	/* time in clocks to wait after the plates where switched */
+	unsigned int		settling_delay;
+	spinlock_t		lock;
+};
+
+static u32 mxs_lradc_plate_mask(struct mxs_lradc *lradc)
+{
+	if (lradc->soc == IMX23_LRADC)
+		return LRADC_CTRL0_MX23_PLATE_MASK;
+	return LRADC_CTRL0_MX28_PLATE_MASK;
+}
+
+static u32 mxs_lradc_touch_detect_bit(struct mxs_lradc *lradc)
+{
+	if (lradc->soc == IMX23_LRADC)
+		return LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE;
+	return LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE;
+}
+
+static u32 mxs_lradc_drive_x_plate(struct mxs_lradc *lradc)
+{
+	if (lradc->soc == IMX23_LRADC)
+		return LRADC_CTRL0_MX23_XP | LRADC_CTRL0_MX23_XM;
+	return LRADC_CTRL0_MX28_XPPSW | LRADC_CTRL0_MX28_XNNSW;
+}
+
+static u32 mxs_lradc_drive_y_plate(struct mxs_lradc *lradc)
+{
+	if (lradc->soc == IMX23_LRADC)
+		return LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_YM;
+	return LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_YNNSW;
+}
+
+static u32 mxs_lradc_drive_pressure(struct mxs_lradc *lradc)
+{
+	if (lradc->soc == IMX23_LRADC)
+		return LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XM;
+	return LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW;
+}
+
+static bool mxs_lradc_check_touch_event(struct mxs_lradc *lradc)
+{
+	return !!(readl(lradc->base + LRADC_STATUS) &
+					LRADC_STATUS_TOUCH_DETECT_RAW);
+}
+
+static void mxs_lradc_map_ts_channel(struct mxs_lradc *lradc, unsigned int vch,
+				     unsigned int ch)
+{
+	mxs_lradc_reg_clear(lradc, LRADC_CTRL4_LRADCSELECT_MASK(vch),
+			    LRADC_CTRL4);
+	mxs_lradc_reg_set(lradc, LRADC_CTRL4_LRADCSELECT(vch, ch), LRADC_CTRL4);
+}
+
+static void mxs_lradc_setup_ts_channel(struct mxs_lradc_ts *ts, unsigned int ch)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	/*
+	 * prepare for oversampling conversion
+	 *
+	 * from the datasheet:
+	 * "The ACCUMULATE bit in the appropriate channel register
+	 * HW_LRADC_CHn must be set to 1 if NUM_SAMPLES is greater then 0;
+	 * otherwise, the IRQs will not fire."
+	 */
+	mxs_lradc_reg_wrt(lradc, LRADC_CH_ACCUMULATE |
+			  LRADC_CH_NUM_SAMPLES(ts->over_sample_cnt - 1),
+			  LRADC_CH(ch));
+
+	/* from the datasheet:
+	 * "Software must clear this register in preparation for a
+	 * multi-cycle accumulation.
+	 */
+	mxs_lradc_reg_clear(lradc, LRADC_CH_VALUE_MASK, LRADC_CH(ch));
+
+	/*
+	 * prepare the delay/loop unit according to the oversampling count
+	 *
+	 * from the datasheet:
+	 * "The DELAY fields in HW_LRADC_DELAY0, HW_LRADC_DELAY1,
+	 * HW_LRADC_DELAY2, and HW_LRADC_DELAY3 must be non-zero; otherwise,
+	 * the LRADC will not trigger the delay group."
+	 */
+	mxs_lradc_reg_wrt(lradc, LRADC_DELAY_TRIGGER(1 << ch) |
+			  LRADC_DELAY_TRIGGER_DELAYS(0) |
+			  LRADC_DELAY_LOOP(ts->over_sample_cnt - 1) |
+			  LRADC_DELAY_DELAY(ts->over_sample_delay - 1),
+			  LRADC_DELAY(3));
+
+	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(ch), LRADC_CTRL1);
+
+	/*
+	 * after changing the touchscreen plates setting
+	 * the signals need some initial time to settle. Start the
+	 * SoC's delay unit and start the conversion later
+	 * and automatically.
+	 */
+	mxs_lradc_reg_wrt(
+		lradc,
+		LRADC_DELAY_TRIGGER(0) | /* don't trigger ADC */
+		LRADC_DELAY_TRIGGER_DELAYS(BIT(3)) | /* trigger DELAY unit#3 */
+		LRADC_DELAY_KICK |
+		LRADC_DELAY_DELAY(ts->settling_delay),
+		LRADC_DELAY(2));
+}
+
+/*
+ * Pressure detection is special:
+ * We want to do both required measurements for the pressure detection in
+ * one turn. Use the hardware features to chain both conversions and let the
+ * hardware report one interrupt if both conversions are done
+ */
+static void mxs_lradc_setup_ts_pressure(struct mxs_lradc_ts *ts,
+					unsigned int ch1, unsigned int ch2)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+	u32 reg;
+
+	/*
+	 * prepare for oversampling conversion
+	 *
+	 * from the datasheet:
+	 * "The ACCUMULATE bit in the appropriate channel register
+	 * HW_LRADC_CHn must be set to 1 if NUM_SAMPLES is greater then 0;
+	 * otherwise, the IRQs will not fire."
+	 */
+	reg = LRADC_CH_ACCUMULATE |
+		LRADC_CH_NUM_SAMPLES(ts->over_sample_cnt - 1);
+	mxs_lradc_reg_wrt(lradc, reg, LRADC_CH(ch1));
+	mxs_lradc_reg_wrt(lradc, reg, LRADC_CH(ch2));
+
+	/* from the datasheet:
+	 * "Software must clear this register in preparation for a
+	 * multi-cycle accumulation.
+	 */
+	mxs_lradc_reg_clear(lradc, LRADC_CH_VALUE_MASK, LRADC_CH(ch1));
+	mxs_lradc_reg_clear(lradc, LRADC_CH_VALUE_MASK, LRADC_CH(ch2));
+
+	/* prepare the delay/loop unit according to the oversampling count */
+	mxs_lradc_reg_wrt(lradc,
+		    LRADC_DELAY_TRIGGER(1 << ch1) |
+		    LRADC_DELAY_TRIGGER(1 << ch2) | /* start both channels */
+		    LRADC_DELAY_TRIGGER_DELAYS(0) |
+		    LRADC_DELAY_LOOP(ts->over_sample_cnt - 1) |
+		    LRADC_DELAY_DELAY(ts->over_sample_delay - 1),
+		    LRADC_DELAY(3));
+
+	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(ch2), LRADC_CTRL1);
+
+	/*
+	 * after changing the touchscreen plates setting
+	 * the signals need some initial time to settle. Start the
+	 * SoC's delay unit and start the conversion later
+	 * and automatically.
+	 */
+	mxs_lradc_reg_wrt(lradc,
+		LRADC_DELAY_TRIGGER(0) | /* don't trigger ADC */
+		LRADC_DELAY_TRIGGER_DELAYS(BIT(3)) | /* trigger DELAY unit#3 */
+		LRADC_DELAY_KICK |
+		LRADC_DELAY_DELAY(ts->settling_delay), LRADC_DELAY(2));
+}
+
+static unsigned int mxs_lradc_ts_read_raw_channel(struct mxs_lradc_ts *ts,
+						  unsigned int channel)
+{
+	u32 reg;
+	unsigned int num_samples, val;
+	struct mxs_lradc *lradc = ts->lradc;
+
+	reg = readl(lradc->base + LRADC_CH(channel));
+	if (reg & LRADC_CH_ACCUMULATE)
+		num_samples = ts->over_sample_cnt;
+	else
+		num_samples = 1;
+
+	val = (reg & LRADC_CH_VALUE_MASK) >> LRADC_CH_VALUE_OFFSET;
+	return val / num_samples;
+}
+
+static unsigned int mxs_lradc_read_ts_pressure(struct mxs_lradc_ts *ts,
+					unsigned int ch1, unsigned int ch2)
+{
+	u32 reg, mask;
+	unsigned int pressure, m1, m2;
+	struct mxs_lradc *lradc = ts->lradc;
+
+	mask = LRADC_CTRL1_LRADC_IRQ(ch1) | LRADC_CTRL1_LRADC_IRQ(ch2);
+	reg = readl(lradc->base + LRADC_CTRL1) & mask;
+
+	while (reg != mask) {
+		reg = readl(lradc->base + LRADC_CTRL1) & mask;
+		dev_dbg(ts->dev, "One channel is still busy: %X\n", reg);
+	}
+
+	m1 = mxs_lradc_ts_read_raw_channel(ts, ch1);
+	m2 = mxs_lradc_ts_read_raw_channel(ts, ch2);
+
+	if (m2 == 0) {
+		dev_warn(ts->dev, "Cannot calculate pressure\n");
+		return 1 << (LRADC_RESOLUTION - 1);
+	}
+
+	/* simply scale the value from 0 ... max ADC resolution */
+	pressure = m1;
+	pressure *= (1 << LRADC_RESOLUTION);
+	pressure /= m2;
+
+	dev_dbg(ts->dev, "Pressure = %u\n", pressure);
+	return pressure;
+}
+
+#define TS_CH_XP 2
+#define TS_CH_YP 3
+#define TS_CH_XM 4
+#define TS_CH_YM 5
+
+/*
+ * YP(open)--+-------------+
+ *	     |		   |--+
+ *	     |		   |  |
+ *    YM(-)--+-------------+  |
+ *	       +--------------+
+ *	       |	      |
+ *	   XP(weak+)	    XM(open)
+ *
+ * "weak+" means 200k Ohm VDDIO
+ * (-) means GND
+ */
+static void mxs_lradc_setup_touch_detection(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	/*
+	 * In order to detect a touch event the 'touch detect enable' bit
+	 * enables:
+	 *  - a weak pullup to the X+ connector
+	 *  - a strong ground at the Y- connector
+	 */
+	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
+	mxs_lradc_reg_set(lradc, mxs_lradc_touch_detect_bit(lradc),
+			  LRADC_CTRL0);
+}
+
+/*
+ * YP(meas)--+-------------+
+ *	     |		   |--+
+ *	     |		   |  |
+ * YM(open)--+-------------+  |
+ *	       +--------------+
+ *	       |	      |
+ *	     XP(+)	    XM(-)
+ *
+ * (+) means here 1.85 V
+ * (-) means here GND
+ */
+static void mxs_lradc_prepare_x_pos(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
+	mxs_lradc_reg_set(lradc, mxs_lradc_drive_x_plate(lradc), LRADC_CTRL0);
+
+	ts->cur_plate = LRADC_SAMPLE_X;
+	mxs_lradc_map_ts_channel(lradc, TOUCHSCREEN_VCHANNEL1, TS_CH_YP);
+	mxs_lradc_setup_ts_channel(ts, TOUCHSCREEN_VCHANNEL1);
+}
+
+/*
+ *   YP(+)--+-------------+
+ *	    |		  |--+
+ *	    |		  |  |
+ *   YM(-)--+-------------+  |
+ *	      +--------------+
+ *	      |		     |
+ *	   XP(open)	   XM(meas)
+ *
+ * (+) means here 1.85 V
+ * (-) means here GND
+ */
+static void mxs_lradc_prepare_y_pos(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
+	mxs_lradc_reg_set(lradc, mxs_lradc_drive_y_plate(lradc), LRADC_CTRL0);
+
+	ts->cur_plate = LRADC_SAMPLE_Y;
+	mxs_lradc_map_ts_channel(lradc, TOUCHSCREEN_VCHANNEL1, TS_CH_XM);
+	mxs_lradc_setup_ts_channel(ts, TOUCHSCREEN_VCHANNEL1);
+}
+
+/*
+ *    YP(+)--+-------------+
+ *	     |		   |--+
+ *	     |		   |  |
+ * YM(meas)--+-------------+  |
+ *	       +--------------+
+ *	       |	      |
+ *	    XP(meas)	    XM(-)
+ *
+ * (+) means here 1.85 V
+ * (-) means here GND
+ */
+static void mxs_lradc_prepare_pressure(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
+	mxs_lradc_reg_set(lradc, mxs_lradc_drive_pressure(lradc), LRADC_CTRL0);
+
+	ts->cur_plate = LRADC_SAMPLE_PRESSURE;
+	mxs_lradc_map_ts_channel(lradc, TOUCHSCREEN_VCHANNEL1, TS_CH_YM);
+	mxs_lradc_map_ts_channel(lradc, TOUCHSCREEN_VCHANNEL2, TS_CH_XP);
+	mxs_lradc_setup_ts_pressure(ts, TOUCHSCREEN_VCHANNEL2,
+				    TOUCHSCREEN_VCHANNEL1);
+}
+
+static void mxs_lradc_enable_touch_detection(struct mxs_lradc_ts *ts)
+{
+	mxs_lradc_setup_touch_detection(ts);
+
+	ts->cur_plate = LRADC_TOUCH;
+	mxs_lradc_reg_clear(ts->lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ |
+			    LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1);
+	mxs_lradc_reg_set(ts->lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
+			  LRADC_CTRL1);
+}
+
+static void mxs_lradc_start_touch_event(struct mxs_lradc_ts *ts)
+{
+	mxs_lradc_reg_clear(ts->lradc,
+			    LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
+			    LRADC_CTRL1);
+	mxs_lradc_reg_set(ts->lradc,
+			  LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1),
+			  LRADC_CTRL1);
+	/*
+	 * start with the Y-pos, because it uses nearly the same plate
+	 * settings like the touch detection
+	 */
+	mxs_lradc_prepare_y_pos(ts);
+}
+
+static void mxs_lradc_report_ts_event(struct mxs_lradc_ts *ts)
+{
+	input_report_abs(ts->ts_input, ABS_X, ts->ts_x_pos);
+	input_report_abs(ts->ts_input, ABS_Y, ts->ts_y_pos);
+	input_report_abs(ts->ts_input, ABS_PRESSURE, ts->ts_pressure);
+	input_report_key(ts->ts_input, BTN_TOUCH, 1);
+	input_sync(ts->ts_input);
+}
+
+static void mxs_lradc_complete_touch_event(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	mxs_lradc_setup_touch_detection(ts);
+	ts->cur_plate = LRADC_SAMPLE_VALID;
+	/*
+	 * start a dummy conversion to burn time to settle the signals
+	 * note: we are not interested in the conversion's value
+	 */
+	mxs_lradc_reg_wrt(lradc, 0, LRADC_CH(TOUCHSCREEN_VCHANNEL1));
+	mxs_lradc_reg_clear(lradc,
+			    LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
+			    LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2),
+			    LRADC_CTRL1);
+	mxs_lradc_reg_wrt(lradc,
+		    LRADC_DELAY_TRIGGER(1 << TOUCHSCREEN_VCHANNEL1) |
+		    LRADC_DELAY_KICK | LRADC_DELAY_DELAY(10), /* waste 5 ms */
+		    LRADC_DELAY(2));
+}
+
+/*
+ * in order to avoid false measurements, report only samples where
+ * the surface is still touched after the position measurement
+ */
+static void mxs_lradc_finish_touch_event(struct mxs_lradc_ts *ts, bool valid)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	/* if it is still touched, report the sample */
+	if (valid && mxs_lradc_check_touch_event(lradc)) {
+		ts->ts_valid = true;
+		mxs_lradc_report_ts_event(ts);
+	}
+
+	/* if it is even still touched, continue with the next measurement */
+	if (mxs_lradc_check_touch_event(lradc)) {
+		mxs_lradc_prepare_y_pos(ts);
+		return;
+	}
+
+	if (ts->ts_valid) {
+		/* signal the release */
+		ts->ts_valid = false;
+		input_report_key(ts->ts_input, BTN_TOUCH, 0);
+		input_sync(ts->ts_input);
+	}
+
+	/* if it is released, wait for the next touch via IRQ */
+	ts->cur_plate = LRADC_TOUCH;
+	mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(2));
+	mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(3));
+	mxs_lradc_reg_clear(lradc,
+			    LRADC_CTRL1_TOUCH_DETECT_IRQ |
+			    LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1) |
+			    LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1),
+			    LRADC_CTRL1);
+	mxs_lradc_reg_set(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1);
+}
+
+/* touchscreen's state machine */
+static void mxs_lradc_handle_touch(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	switch (ts->cur_plate) {
+	case LRADC_TOUCH:
+		if (mxs_lradc_check_touch_event(lradc))
+			mxs_lradc_start_touch_event(ts);
+		mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ,
+				    LRADC_CTRL1);
+		return;
+
+	case LRADC_SAMPLE_Y:
+		ts->ts_y_pos =
+		    mxs_lradc_ts_read_raw_channel(ts, TOUCHSCREEN_VCHANNEL1);
+		mxs_lradc_prepare_x_pos(ts);
+		return;
+
+	case LRADC_SAMPLE_X:
+		ts->ts_x_pos =
+		    mxs_lradc_ts_read_raw_channel(ts, TOUCHSCREEN_VCHANNEL1);
+		mxs_lradc_prepare_pressure(ts);
+		return;
+
+	case LRADC_SAMPLE_PRESSURE:
+		ts->ts_pressure =
+		    mxs_lradc_read_ts_pressure(ts,
+					       TOUCHSCREEN_VCHANNEL2,
+					       TOUCHSCREEN_VCHANNEL1);
+		mxs_lradc_complete_touch_event(ts);
+		return;
+
+	case LRADC_SAMPLE_VALID:
+		mxs_lradc_finish_touch_event(ts, 1);
+		break;
+	}
+}
+
+/* IRQ Handling */
+static irqreturn_t mxs_lradc_ts_handle_irq(int irq, void *data)
+{
+	struct mxs_lradc_ts *ts = data;
+	struct mxs_lradc *lradc = ts->lradc;
+	unsigned long reg = readl(lradc->base + LRADC_CTRL1);
+	u32 clr_irq = mxs_lradc_irq_mask(lradc);
+	const u32 ts_irq_mask =
+		LRADC_CTRL1_TOUCH_DETECT_IRQ |
+		LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
+		LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2);
+	unsigned long flags;
+
+	if (!(reg & mxs_lradc_irq_mask(lradc)))
+		return IRQ_NONE;
+
+	if (reg & ts_irq_mask) {
+		spin_lock_irqsave(&ts->lock, flags);
+		mxs_lradc_handle_touch(ts);
+		spin_unlock_irqrestore(&ts->lock, flags);
+		/* Make sure we don't clear the next conversion's interrupt. */
+		clr_irq &= ~(LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
+				LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2));
+		mxs_lradc_reg_clear(lradc, reg & clr_irq, LRADC_CTRL1);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int mxs_lradc_ts_open(struct input_dev *dev)
+{
+	struct mxs_lradc_ts *ts = input_get_drvdata(dev);
+
+	/* Enable the touch-detect circuitry. */
+	mxs_lradc_enable_touch_detection(ts);
+
+	return 0;
+}
+
+static void mxs_lradc_ts_stop(struct mxs_lradc_ts *ts)
+{
+	int i;
+	struct mxs_lradc *lradc = ts->lradc;
+
+	/* stop all interrupts from firing */
+	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN |
+		LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1) |
+		LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL2), LRADC_CTRL1);
+
+	/* Power-down touchscreen touch-detect circuitry. */
+	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
+
+	mxs_lradc_reg_clear(lradc,
+			lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
+			LRADC_CTRL1);
+
+	for (i = 1; i < LRADC_MAX_DELAY_CHANS; i++)
+		mxs_lradc_reg_wrt(ts->lradc, 0, LRADC_DELAY(i));
+}
+
+static void mxs_lradc_ts_close(struct input_dev *dev)
+{
+	struct mxs_lradc_ts *ts = input_get_drvdata(dev);
+
+	mxs_lradc_ts_stop(ts);
+}
+
+static void mxs_lradc_ts_hw_init(struct mxs_lradc_ts *ts)
+{
+	struct mxs_lradc *lradc = ts->lradc;
+
+	/* Configure the touchscreen type */
+	if (lradc->soc == IMX28_LRADC) {
+		mxs_lradc_reg_clear(lradc, LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
+				    LRADC_CTRL0);
+
+		if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE)
+			mxs_lradc_reg_set(lradc,
+					  LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
+					  LRADC_CTRL0);
+	}
+}
+
+static int mxs_lradc_ts_register(struct mxs_lradc_ts *ts)
+{
+	struct input_dev *input = ts->ts_input;
+	struct device *dev = ts->dev;
+
+	input = devm_input_allocate_device(dev);
+	if (!input)
+		return -ENOMEM;
+
+	input->name = DRIVER_NAME_TS;
+	input->id.bustype = BUS_HOST;
+	input->open = mxs_lradc_ts_open;
+	input->close = mxs_lradc_ts_close;
+
+	__set_bit(EV_ABS, input->evbit);
+	__set_bit(EV_KEY, input->evbit);
+	__set_bit(BTN_TOUCH, input->keybit);
+	__set_bit(INPUT_PROP_DIRECT, input->propbit);
+	input_set_abs_params(input, ABS_X, 0, LRADC_SINGLE_SAMPLE_MASK, 0, 0);
+	input_set_abs_params(input, ABS_Y, 0, LRADC_SINGLE_SAMPLE_MASK, 0, 0);
+	input_set_abs_params(input, ABS_PRESSURE, 0, LRADC_SINGLE_SAMPLE_MASK,
+			     0, 0);
+
+	ts->ts_input = input;
+	input_set_drvdata(input, ts);
+
+	return input_register_device(input);
+}
+
+static int mxs_lradc_ts_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *node = dev->parent->of_node;
+	struct mxs_lradc *lradc = dev_get_platdata(dev);
+	struct mxs_lradc_ts *ts;
+	int touch_ret, ret, i, j;
+	u32 ts_wires = 0, adapt;
+	const int *irq;
+
+	ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, ts);
+
+	ts->lradc = lradc;
+	ts->dev = dev;
+	spin_lock_init(&ts->lock);
+
+	touch_ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
+					 &ts_wires);
+
+	if (of_property_read_u32(node, "fsl,ave-ctrl", &adapt)) {
+		ts->over_sample_cnt = 4;
+	} else {
+		if (adapt >= 1 || adapt <= 32) {
+			ts->over_sample_cnt = adapt;
+		} else {
+			dev_err(ts->dev, "Invalid sample count (%u)\n",
+				adapt);
+			return -EINVAL;
+		}
+	}
+
+	if (of_property_read_u32(node, "fsl,ave-delay", &adapt)) {
+		ts->over_sample_delay = 2;
+	} else {
+		if (adapt >= 2 || adapt <= LRADC_DELAY_DELAY_MASK + 1) {
+			ts->over_sample_delay = adapt;
+		} else {
+			dev_err(ts->dev, "Invalid sample delay (%u)\n",
+				adapt);
+			return -EINVAL;
+		}
+	}
+
+	if (of_property_read_u32(node, "fsl,settling", &adapt)) {
+		ts->settling_delay = 10;
+	} else {
+		if (adapt >= 1 || adapt <= LRADC_DELAY_DELAY_MASK) {
+			ts->settling_delay = adapt;
+		} else {
+			dev_err(ts->dev, "Invalid settling delay (%u)\n",
+				adapt);
+			return -EINVAL;
+		}
+	}
+
+	mxs_lradc_ts_hw_init(ts);
+
+	irq = mxs_lradc_ts_irq[lradc->soc];
+	for (i = 0; i < 3; i++) {
+		j = irq[i];
+		ret = devm_request_irq(dev, lradc->irq[j],
+				       mxs_lradc_ts_handle_irq,
+				       0, lradc->irq_name[j], ts);
+		if (ret)
+			return ret;
+	}
+
+	if (!touch_ret) {
+		ret = mxs_lradc_ts_register(ts);
+		if (!ret)
+			goto error;
+	}
+
+	return 0;
+
+error:
+	mxs_lradc_ts_stop(ts);
+
+	return ret;
+}
+
+static struct platform_driver mxs_lradc_ts_driver = {
+	.driver	= {
+		.name = DRIVER_NAME_TS,
+	},
+	.probe	= mxs_lradc_ts_probe,
+};
+module_platform_driver(mxs_lradc_ts_driver);
+
+MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
+MODULE_DESCRIPTION("Freescale MXS LRADC touchscreen driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME_TS);
-- 
1.9.1

[PATCH v3 4/4] iio: adc: mxs-lradc: Remove driver

[Ksenija Stanojevic]

Since the driver has been split into mfd there is no reason for it to
stay, so remove it.

Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
---
Changes in v3:
 - none

Changes in v2:
 - none

 drivers/iio/adc/Kconfig     |   14 -
 drivers/iio/adc/Makefile    |    1 -
 drivers/iio/adc/mxs-lradc.c | 1775 -------------------------------------------
 3 files changed, 1790 deletions(-)
 delete mode 100644 drivers/iio/adc/mxs-lradc.c

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 4ef3ad1..5aba3fe 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -310,20 +310,6 @@ config MEN_Z188_ADC
 	  This driver can also be built as a module. If so, the module will be
 	  called men_z188_adc.
 
-config MXS_LRADC
-        tristate "Freescale i.MX23/i.MX28 LRADC"
-        depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM
-        depends on INPUT
-        select STMP_DEVICE
-        select IIO_BUFFER
-        select IIO_TRIGGERED_BUFFER
-        help
-          Say yes here to build support for i.MX23/i.MX28 LRADC convertor
-          built into these chips.
-
-          To compile this driver as a module, choose M here: the
-          module will be called mxs-lradc.
-
 config NAU7802
 	tristate "Nuvoton NAU7802 ADC driver"
 	depends on I2C
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 9bb35c4..b2382ab 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -30,7 +30,6 @@ obj-$(CONFIG_MCP320X) += mcp320x.o
 obj-$(CONFIG_MCP3422) += mcp3422.o
 obj-$(CONFIG_MEN_Z188_ADC) += men_z188_adc.o
 obj-$(CONFIG_MXS_LRADC_ADC) += mxs-lradc-adc.o
-obj-$(CONFIG_MXS_LRADC) += mxs-lradc.o
 obj-$(CONFIG_NAU7802) += nau7802.o
 obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o
 obj-$(CONFIG_QCOM_SPMI_IADC) += qcom-spmi-iadc.o
diff --git a/drivers/iio/adc/mxs-lradc.c b/drivers/iio/adc/mxs-lradc.c
deleted file mode 100644
index 33051b8..0000000
--- a/drivers/iio/adc/mxs-lradc.c
+++ /dev/null
@@ -1,1775 +0,0 @@
-/*
- * Freescale MXS LRADC driver
- *
- * Copyright (c) 2012 DENX Software Engineering, GmbH.
- * Marek Vasut <marex@denx.de>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#include <linux/bitops.h>
-#include <linux/clk.h>
-#include <linux/completion.h>
-#include <linux/device.h>
-#include <linux/err.h>
-#include <linux/input.h>
-#include <linux/interrupt.h>
-#include <linux/io.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
-#include <linux/stmp_device.h>
-#include <linux/sysfs.h>
-
-#include <linux/iio/buffer.h>
-#include <linux/iio/iio.h>
-#include <linux/iio/trigger.h>
-#include <linux/iio/trigger_consumer.h>
-#include <linux/iio/triggered_buffer.h>
-#include <linux/iio/sysfs.h>
-
-#define DRIVER_NAME		"mxs-lradc"
-
-#define LRADC_MAX_DELAY_CHANS	4
-#define LRADC_MAX_MAPPED_CHANS	8
-#define LRADC_MAX_TOTAL_CHANS	16
-
-#define LRADC_DELAY_TIMER_HZ	2000
-
-/*
- * Make this runtime configurable if necessary. Currently, if the buffered mode
- * is enabled, the LRADC takes LRADC_DELAY_TIMER_LOOP samples of data before
- * triggering IRQ. The sampling happens every (LRADC_DELAY_TIMER_PER / 2000)
- * seconds. The result is that the samples arrive every 500mS.
- */
-#define LRADC_DELAY_TIMER_PER	200
-#define LRADC_DELAY_TIMER_LOOP	5
-
-/*
- * Once the pen touches the touchscreen, the touchscreen switches from
- * IRQ-driven mode to polling mode to prevent interrupt storm. The polling
- * is realized by worker thread, which is called every 20 or so milliseconds.
- * This gives the touchscreen enough fluency and does not strain the system
- * too much.
- */
-#define LRADC_TS_SAMPLE_DELAY_MS	5
-
-/*
- * The LRADC reads the following amount of samples from each touchscreen
- * channel and the driver then computes average of these.
- */
-#define LRADC_TS_SAMPLE_AMOUNT		4
-
-enum mxs_lradc_id {
-	IMX23_LRADC,
-	IMX28_LRADC,
-};
-
-static const char * const mx23_lradc_irq_names[] = {
-	"mxs-lradc-touchscreen",
-	"mxs-lradc-channel0",
-	"mxs-lradc-channel1",
-	"mxs-lradc-channel2",
-	"mxs-lradc-channel3",
-	"mxs-lradc-channel4",
-	"mxs-lradc-channel5",
-	"mxs-lradc-channel6",
-	"mxs-lradc-channel7",
-};
-
-static const char * const mx28_lradc_irq_names[] = {
-	"mxs-lradc-touchscreen",
-	"mxs-lradc-thresh0",
-	"mxs-lradc-thresh1",
-	"mxs-lradc-channel0",
-	"mxs-lradc-channel1",
-	"mxs-lradc-channel2",
-	"mxs-lradc-channel3",
-	"mxs-lradc-channel4",
-	"mxs-lradc-channel5",
-	"mxs-lradc-channel6",
-	"mxs-lradc-channel7",
-	"mxs-lradc-button0",
-	"mxs-lradc-button1",
-};
-
-struct mxs_lradc_of_config {
-	const int		irq_count;
-	const char * const	*irq_name;
-	const u32		*vref_mv;
-};
-
-#define VREF_MV_BASE 1850
-
-static const u32 mx23_vref_mv[LRADC_MAX_TOTAL_CHANS] = {
-	VREF_MV_BASE,		/* CH0 */
-	VREF_MV_BASE,		/* CH1 */
-	VREF_MV_BASE,		/* CH2 */
-	VREF_MV_BASE,		/* CH3 */
-	VREF_MV_BASE,		/* CH4 */
-	VREF_MV_BASE,		/* CH5 */
-	VREF_MV_BASE * 2,	/* CH6 VDDIO */
-	VREF_MV_BASE * 4,	/* CH7 VBATT */
-	VREF_MV_BASE,		/* CH8 Temp sense 0 */
-	VREF_MV_BASE,		/* CH9 Temp sense 1 */
-	VREF_MV_BASE,		/* CH10 */
-	VREF_MV_BASE,		/* CH11 */
-	VREF_MV_BASE,		/* CH12 USB_DP */
-	VREF_MV_BASE,		/* CH13 USB_DN */
-	VREF_MV_BASE,		/* CH14 VBG */
-	VREF_MV_BASE * 4,	/* CH15 VDD5V */
-};
-
-static const u32 mx28_vref_mv[LRADC_MAX_TOTAL_CHANS] = {
-	VREF_MV_BASE,		/* CH0 */
-	VREF_MV_BASE,		/* CH1 */
-	VREF_MV_BASE,		/* CH2 */
-	VREF_MV_BASE,		/* CH3 */
-	VREF_MV_BASE,		/* CH4 */
-	VREF_MV_BASE,		/* CH5 */
-	VREF_MV_BASE,		/* CH6 */
-	VREF_MV_BASE * 4,	/* CH7 VBATT */
-	VREF_MV_BASE,		/* CH8 Temp sense 0 */
-	VREF_MV_BASE,		/* CH9 Temp sense 1 */
-	VREF_MV_BASE * 2,	/* CH10 VDDIO */
-	VREF_MV_BASE,		/* CH11 VTH */
-	VREF_MV_BASE * 2,	/* CH12 VDDA */
-	VREF_MV_BASE,		/* CH13 VDDD */
-	VREF_MV_BASE,		/* CH14 VBG */
-	VREF_MV_BASE * 4,	/* CH15 VDD5V */
-};
-
-static const struct mxs_lradc_of_config mxs_lradc_of_config[] = {
-	[IMX23_LRADC] = {
-		.irq_count	= ARRAY_SIZE(mx23_lradc_irq_names),
-		.irq_name	= mx23_lradc_irq_names,
-		.vref_mv	= mx23_vref_mv,
-	},
-	[IMX28_LRADC] = {
-		.irq_count	= ARRAY_SIZE(mx28_lradc_irq_names),
-		.irq_name	= mx28_lradc_irq_names,
-		.vref_mv	= mx28_vref_mv,
-	},
-};
-
-enum mxs_lradc_ts {
-	MXS_LRADC_TOUCHSCREEN_NONE = 0,
-	MXS_LRADC_TOUCHSCREEN_4WIRE,
-	MXS_LRADC_TOUCHSCREEN_5WIRE,
-};
-
-/*
- * Touchscreen handling
- */
-enum lradc_ts_plate {
-	LRADC_TOUCH = 0,
-	LRADC_SAMPLE_X,
-	LRADC_SAMPLE_Y,
-	LRADC_SAMPLE_PRESSURE,
-	LRADC_SAMPLE_VALID,
-};
-
-enum mxs_lradc_divbytwo {
-	MXS_LRADC_DIV_DISABLED = 0,
-	MXS_LRADC_DIV_ENABLED,
-};
-
-struct mxs_lradc_scale {
-	unsigned int		integer;
-	unsigned int		nano;
-};
-
-struct mxs_lradc {
-	struct device		*dev;
-	void __iomem		*base;
-	int			irq[13];
-
-	struct clk		*clk;
-
-	u32			*buffer;
-	struct iio_trigger	*trig;
-
-	struct mutex		lock;
-
-	struct completion	completion;
-
-	const u32		*vref_mv;
-	struct mxs_lradc_scale	scale_avail[LRADC_MAX_TOTAL_CHANS][2];
-	unsigned long		is_divided;
-
-	/*
-	 * When the touchscreen is enabled, we give it two private virtual
-	 * channels: #6 and #7. This means that only 6 virtual channels (instead
-	 * of 8) will be available for buffered capture.
-	 */
-#define TOUCHSCREEN_VCHANNEL1		7
-#define TOUCHSCREEN_VCHANNEL2		6
-#define BUFFER_VCHANS_LIMITED		0x3f
-#define BUFFER_VCHANS_ALL		0xff
-	u8			buffer_vchans;
-
-	/*
-	 * Furthermore, certain LRADC channels are shared between touchscreen
-	 * and/or touch-buttons and generic LRADC block. Therefore when using
-	 * either of these, these channels are not available for the regular
-	 * sampling. The shared channels are as follows:
-	 *
-	 * CH0 -- Touch button #0
-	 * CH1 -- Touch button #1
-	 * CH2 -- Touch screen XPUL
-	 * CH3 -- Touch screen YPLL
-	 * CH4 -- Touch screen XNUL
-	 * CH5 -- Touch screen YNLR
-	 * CH6 -- Touch screen WIPER (5-wire only)
-	 *
-	 * The bit fields below represents which parts of the LRADC block are
-	 * switched into special mode of operation. These channels can not
-	 * be sampled as regular LRADC channels. The driver will refuse any
-	 * attempt to sample these channels.
-	 */
-#define CHAN_MASK_TOUCHBUTTON		(BIT(1) | BIT(0))
-#define CHAN_MASK_TOUCHSCREEN_4WIRE	(0xf << 2)
-#define CHAN_MASK_TOUCHSCREEN_5WIRE	(0x1f << 2)
-	enum mxs_lradc_ts	use_touchscreen;
-	bool			use_touchbutton;
-
-	struct input_dev	*ts_input;
-
-	enum mxs_lradc_id	soc;
-	enum lradc_ts_plate	cur_plate; /* state machine */
-	bool			ts_valid;
-	unsigned		ts_x_pos;
-	unsigned		ts_y_pos;
-	unsigned		ts_pressure;
-
-	/* handle touchscreen's physical behaviour */
-	/* samples per coordinate */
-	unsigned		over_sample_cnt;
-	/* time clocks between samples */
-	unsigned		over_sample_delay;
-	/* time in clocks to wait after the plates where switched */
-	unsigned		settling_delay;
-};
-
-#define	LRADC_CTRL0				0x00
-# define LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE	BIT(23)
-# define LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE	BIT(22)
-# define LRADC_CTRL0_MX28_YNNSW	/* YM */	BIT(21)
-# define LRADC_CTRL0_MX28_YPNSW	/* YP */	BIT(20)
-# define LRADC_CTRL0_MX28_YPPSW	/* YP */	BIT(19)
-# define LRADC_CTRL0_MX28_XNNSW	/* XM */	BIT(18)
-# define LRADC_CTRL0_MX28_XNPSW	/* XM */	BIT(17)
-# define LRADC_CTRL0_MX28_XPPSW	/* XP */	BIT(16)
-
-# define LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE	BIT(20)
-# define LRADC_CTRL0_MX23_YM			BIT(19)
-# define LRADC_CTRL0_MX23_XM			BIT(18)
-# define LRADC_CTRL0_MX23_YP			BIT(17)
-# define LRADC_CTRL0_MX23_XP			BIT(16)
-
-# define LRADC_CTRL0_MX28_PLATE_MASK \
-		(LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE | \
-		LRADC_CTRL0_MX28_YNNSW | LRADC_CTRL0_MX28_YPNSW | \
-		LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW | \
-		LRADC_CTRL0_MX28_XNPSW | LRADC_CTRL0_MX28_XPPSW)
-
-# define LRADC_CTRL0_MX23_PLATE_MASK \
-		(LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE | \
-		LRADC_CTRL0_MX23_YM | LRADC_CTRL0_MX23_XM | \
-		LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XP)
-
-#define	LRADC_CTRL1				0x10
-#define	LRADC_CTRL1_TOUCH_DETECT_IRQ_EN		BIT(24)
-#define	LRADC_CTRL1_LRADC_IRQ_EN(n)		(1 << ((n) + 16))
-#define	LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK	(0x1fff << 16)
-#define	LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK	(0x01ff << 16)
-#define	LRADC_CTRL1_LRADC_IRQ_EN_OFFSET		16
-#define	LRADC_CTRL1_TOUCH_DETECT_IRQ		BIT(8)
-#define	LRADC_CTRL1_LRADC_IRQ(n)		(1 << (n))
-#define	LRADC_CTRL1_MX28_LRADC_IRQ_MASK		0x1fff
-#define	LRADC_CTRL1_MX23_LRADC_IRQ_MASK		0x01ff
-#define	LRADC_CTRL1_LRADC_IRQ_OFFSET		0
-
-#define	LRADC_CTRL2				0x20
-#define	LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET	24
-#define	LRADC_CTRL2_TEMPSENSE_PWD		BIT(15)
-
-#define	LRADC_STATUS				0x40
-#define	LRADC_STATUS_TOUCH_DETECT_RAW		BIT(0)
-
-#define	LRADC_CH(n)				(0x50 + (0x10 * (n)))
-#define	LRADC_CH_ACCUMULATE			BIT(29)
-#define	LRADC_CH_NUM_SAMPLES_MASK		(0x1f << 24)
-#define	LRADC_CH_NUM_SAMPLES_OFFSET		24
-#define	LRADC_CH_NUM_SAMPLES(x) \
-				((x) << LRADC_CH_NUM_SAMPLES_OFFSET)
-#define	LRADC_CH_VALUE_MASK			0x3ffff
-#define	LRADC_CH_VALUE_OFFSET			0
-
-#define	LRADC_DELAY(n)				(0xd0 + (0x10 * (n)))
-#define	LRADC_DELAY_TRIGGER_LRADCS_MASK		(0xffUL << 24)
-#define	LRADC_DELAY_TRIGGER_LRADCS_OFFSET	24
-#define	LRADC_DELAY_TRIGGER(x) \
-				(((x) << LRADC_DELAY_TRIGGER_LRADCS_OFFSET) & \
-				LRADC_DELAY_TRIGGER_LRADCS_MASK)
-#define	LRADC_DELAY_KICK			BIT(20)
-#define	LRADC_DELAY_TRIGGER_DELAYS_MASK		(0xf << 16)
-#define	LRADC_DELAY_TRIGGER_DELAYS_OFFSET	16
-#define	LRADC_DELAY_TRIGGER_DELAYS(x) \
-				(((x) << LRADC_DELAY_TRIGGER_DELAYS_OFFSET) & \
-				LRADC_DELAY_TRIGGER_DELAYS_MASK)
-#define	LRADC_DELAY_LOOP_COUNT_MASK		(0x1f << 11)
-#define	LRADC_DELAY_LOOP_COUNT_OFFSET		11
-#define	LRADC_DELAY_LOOP(x) \
-				(((x) << LRADC_DELAY_LOOP_COUNT_OFFSET) & \
-				LRADC_DELAY_LOOP_COUNT_MASK)
-#define	LRADC_DELAY_DELAY_MASK			0x7ff
-#define	LRADC_DELAY_DELAY_OFFSET		0
-#define	LRADC_DELAY_DELAY(x) \
-				(((x) << LRADC_DELAY_DELAY_OFFSET) & \
-				LRADC_DELAY_DELAY_MASK)
-
-#define	LRADC_CTRL4				0x140
-#define	LRADC_CTRL4_LRADCSELECT_MASK(n)		(0xf << ((n) * 4))
-#define	LRADC_CTRL4_LRADCSELECT_OFFSET(n)	((n) * 4)
-#define	LRADC_CTRL4_LRADCSELECT(n, x) \
-				(((x) << LRADC_CTRL4_LRADCSELECT_OFFSET(n)) & \
-				LRADC_CTRL4_LRADCSELECT_MASK(n))
-
-#define LRADC_RESOLUTION			12
-#define LRADC_SINGLE_SAMPLE_MASK		((1 << LRADC_RESOLUTION) - 1)
-
-static void mxs_lradc_reg_set(struct mxs_lradc *lradc, u32 val, u32 reg)
-{
-	writel(val, lradc->base + reg + STMP_OFFSET_REG_SET);
-}
-
-static void mxs_lradc_reg_clear(struct mxs_lradc *lradc, u32 val, u32 reg)
-{
-	writel(val, lradc->base + reg + STMP_OFFSET_REG_CLR);
-}
-
-static void mxs_lradc_reg_wrt(struct mxs_lradc *lradc, u32 val, u32 reg)
-{
-	writel(val, lradc->base + reg);
-}
-
-static u32 mxs_lradc_plate_mask(struct mxs_lradc *lradc)
-{
-	if (lradc->soc == IMX23_LRADC)
-		return LRADC_CTRL0_MX23_PLATE_MASK;
-	return LRADC_CTRL0_MX28_PLATE_MASK;
-}
-
-static u32 mxs_lradc_irq_en_mask(struct mxs_lradc *lradc)
-{
-	if (lradc->soc == IMX23_LRADC)
-		return LRADC_CTRL1_MX23_LRADC_IRQ_EN_MASK;
-	return LRADC_CTRL1_MX28_LRADC_IRQ_EN_MASK;
-}
-
-static u32 mxs_lradc_irq_mask(struct mxs_lradc *lradc)
-{
-	if (lradc->soc == IMX23_LRADC)
-		return LRADC_CTRL1_MX23_LRADC_IRQ_MASK;
-	return LRADC_CTRL1_MX28_LRADC_IRQ_MASK;
-}
-
-static u32 mxs_lradc_touch_detect_bit(struct mxs_lradc *lradc)
-{
-	if (lradc->soc == IMX23_LRADC)
-		return LRADC_CTRL0_MX23_TOUCH_DETECT_ENABLE;
-	return LRADC_CTRL0_MX28_TOUCH_DETECT_ENABLE;
-}
-
-static u32 mxs_lradc_drive_x_plate(struct mxs_lradc *lradc)
-{
-	if (lradc->soc == IMX23_LRADC)
-		return LRADC_CTRL0_MX23_XP | LRADC_CTRL0_MX23_XM;
-	return LRADC_CTRL0_MX28_XPPSW | LRADC_CTRL0_MX28_XNNSW;
-}
-
-static u32 mxs_lradc_drive_y_plate(struct mxs_lradc *lradc)
-{
-	if (lradc->soc == IMX23_LRADC)
-		return LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_YM;
-	return LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_YNNSW;
-}
-
-static u32 mxs_lradc_drive_pressure(struct mxs_lradc *lradc)
-{
-	if (lradc->soc == IMX23_LRADC)
-		return LRADC_CTRL0_MX23_YP | LRADC_CTRL0_MX23_XM;
-	return LRADC_CTRL0_MX28_YPPSW | LRADC_CTRL0_MX28_XNNSW;
-}
-
-static bool mxs_lradc_check_touch_event(struct mxs_lradc *lradc)
-{
-	return !!(readl(lradc->base + LRADC_STATUS) &
-					LRADC_STATUS_TOUCH_DETECT_RAW);
-}
-
-static void mxs_lradc_map_channel(struct mxs_lradc *lradc, unsigned vch,
-				  unsigned ch)
-{
-	mxs_lradc_reg_clear(lradc, LRADC_CTRL4_LRADCSELECT_MASK(vch),
-			    LRADC_CTRL4);
-	mxs_lradc_reg_set(lradc, LRADC_CTRL4_LRADCSELECT(vch, ch), LRADC_CTRL4);
-}
-
-static void mxs_lradc_setup_ts_channel(struct mxs_lradc *lradc, unsigned ch)
-{
-	/*
-	 * prepare for oversampling conversion
-	 *
-	 * from the datasheet:
-	 * "The ACCUMULATE bit in the appropriate channel register
-	 * HW_LRADC_CHn must be set to 1 if NUM_SAMPLES is greater then 0;
-	 * otherwise, the IRQs will not fire."
-	 */
-	mxs_lradc_reg_wrt(lradc, LRADC_CH_ACCUMULATE |
-			  LRADC_CH_NUM_SAMPLES(lradc->over_sample_cnt - 1),
-			  LRADC_CH(ch));
-
-	/*
-	 * from the datasheet:
-	 * "Software must clear this register in preparation for a
-	 * multi-cycle accumulation.
-	 */
-	mxs_lradc_reg_clear(lradc, LRADC_CH_VALUE_MASK, LRADC_CH(ch));
-
-	/*
-	 * prepare the delay/loop unit according to the oversampling count
-	 *
-	 * from the datasheet:
-	 * "The DELAY fields in HW_LRADC_DELAY0, HW_LRADC_DELAY1,
-	 * HW_LRADC_DELAY2, and HW_LRADC_DELAY3 must be non-zero; otherwise,
-	 * the LRADC will not trigger the delay group."
-	 */
-	mxs_lradc_reg_wrt(lradc, LRADC_DELAY_TRIGGER(1 << ch) |
-			  LRADC_DELAY_TRIGGER_DELAYS(0) |
-			  LRADC_DELAY_LOOP(lradc->over_sample_cnt - 1) |
-			  LRADC_DELAY_DELAY(lradc->over_sample_delay - 1),
-			  LRADC_DELAY(3));
-
-	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(ch), LRADC_CTRL1);
-
-	/*
-	 * after changing the touchscreen plates setting
-	 * the signals need some initial time to settle. Start the
-	 * SoC's delay unit and start the conversion later
-	 * and automatically.
-	 */
-	mxs_lradc_reg_wrt(
-		lradc,
-		LRADC_DELAY_TRIGGER(0) | /* don't trigger ADC */
-		LRADC_DELAY_TRIGGER_DELAYS(BIT(3)) | /* trigger DELAY unit#3 */
-		LRADC_DELAY_KICK |
-		LRADC_DELAY_DELAY(lradc->settling_delay),
-		LRADC_DELAY(2));
-}
-
-/*
- * Pressure detection is special:
- * We want to do both required measurements for the pressure detection in
- * one turn. Use the hardware features to chain both conversions and let the
- * hardware report one interrupt if both conversions are done
- */
-static void mxs_lradc_setup_ts_pressure(struct mxs_lradc *lradc, unsigned ch1,
-					unsigned ch2)
-{
-	u32 reg;
-
-	/*
-	 * prepare for oversampling conversion
-	 *
-	 * from the datasheet:
-	 * "The ACCUMULATE bit in the appropriate channel register
-	 * HW_LRADC_CHn must be set to 1 if NUM_SAMPLES is greater then 0;
-	 * otherwise, the IRQs will not fire."
-	 */
-	reg = LRADC_CH_ACCUMULATE |
-		LRADC_CH_NUM_SAMPLES(lradc->over_sample_cnt - 1);
-	mxs_lradc_reg_wrt(lradc, reg, LRADC_CH(ch1));
-	mxs_lradc_reg_wrt(lradc, reg, LRADC_CH(ch2));
-
-	/*
-	 * from the datasheet:
-	 * "Software must clear this register in preparation for a
-	 * multi-cycle accumulation.
-	 */
-	mxs_lradc_reg_clear(lradc, LRADC_CH_VALUE_MASK, LRADC_CH(ch1));
-	mxs_lradc_reg_clear(lradc, LRADC_CH_VALUE_MASK, LRADC_CH(ch2));
-
-	/* prepare the delay/loop unit according to the oversampling count */
-	mxs_lradc_reg_wrt(
-		    lradc,
-		    LRADC_DELAY_TRIGGER(1 << ch1) |
-		    LRADC_DELAY_TRIGGER(1 << ch2) | /* start both channels */
-		    LRADC_DELAY_TRIGGER_DELAYS(0) |
-		    LRADC_DELAY_LOOP(lradc->over_sample_cnt - 1) |
-		    LRADC_DELAY_DELAY(lradc->over_sample_delay - 1),
-		    LRADC_DELAY(3));
-
-	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ(ch2), LRADC_CTRL1);
-
-	/*
-	 * after changing the touchscreen plates setting
-	 * the signals need some initial time to settle. Start the
-	 * SoC's delay unit and start the conversion later
-	 * and automatically.
-	 */
-	mxs_lradc_reg_wrt(
-		lradc,
-		LRADC_DELAY_TRIGGER(0) | /* don't trigger ADC */
-		LRADC_DELAY_TRIGGER_DELAYS(BIT(3)) | /* trigger DELAY unit#3 */
-		LRADC_DELAY_KICK |
-		LRADC_DELAY_DELAY(lradc->settling_delay), LRADC_DELAY(2));
-}
-
-static unsigned mxs_lradc_read_raw_channel(struct mxs_lradc *lradc,
-					   unsigned channel)
-{
-	u32 reg;
-	unsigned num_samples, val;
-
-	reg = readl(lradc->base + LRADC_CH(channel));
-	if (reg & LRADC_CH_ACCUMULATE)
-		num_samples = lradc->over_sample_cnt;
-	else
-		num_samples = 1;
-
-	val = (reg & LRADC_CH_VALUE_MASK) >> LRADC_CH_VALUE_OFFSET;
-	return val / num_samples;
-}
-
-static unsigned mxs_lradc_read_ts_pressure(struct mxs_lradc *lradc,
-					   unsigned ch1, unsigned ch2)
-{
-	u32 reg, mask;
-	unsigned pressure, m1, m2;
-
-	mask = LRADC_CTRL1_LRADC_IRQ(ch1) | LRADC_CTRL1_LRADC_IRQ(ch2);
-	reg = readl(lradc->base + LRADC_CTRL1) & mask;
-
-	while (reg != mask) {
-		reg = readl(lradc->base + LRADC_CTRL1) & mask;
-		dev_dbg(lradc->dev, "One channel is still busy: %X\n", reg);
-	}
-
-	m1 = mxs_lradc_read_raw_channel(lradc, ch1);
-	m2 = mxs_lradc_read_raw_channel(lradc, ch2);
-
-	if (m2 == 0) {
-		dev_warn(lradc->dev, "Cannot calculate pressure\n");
-		return 1 << (LRADC_RESOLUTION - 1);
-	}
-
-	/* simply scale the value from 0 ... max ADC resolution */
-	pressure = m1;
-	pressure *= (1 << LRADC_RESOLUTION);
-	pressure /= m2;
-
-	dev_dbg(lradc->dev, "Pressure = %u\n", pressure);
-	return pressure;
-}
-
-#define TS_CH_XP 2
-#define TS_CH_YP 3
-#define TS_CH_XM 4
-#define TS_CH_YM 5
-
-/*
- * YP(open)--+-------------+
- *           |             |--+
- *           |             |  |
- *    YM(-)--+-------------+  |
- *             +--------------+
- *             |              |
- *         XP(weak+)        XM(open)
- *
- * "weak+" means 200k Ohm VDDIO
- * (-) means GND
- */
-static void mxs_lradc_setup_touch_detection(struct mxs_lradc *lradc)
-{
-	/*
-	 * In order to detect a touch event the 'touch detect enable' bit
-	 * enables:
-	 *  - a weak pullup to the X+ connector
-	 *  - a strong ground at the Y- connector
-	 */
-	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
-	mxs_lradc_reg_set(lradc, mxs_lradc_touch_detect_bit(lradc),
-			  LRADC_CTRL0);
-}
-
-/*
- * YP(meas)--+-------------+
- *           |             |--+
- *           |             |  |
- * YM(open)--+-------------+  |
- *             +--------------+
- *             |              |
- *           XP(+)          XM(-)
- *
- * (+) means here 1.85 V
- * (-) means here GND
- */
-static void mxs_lradc_prepare_x_pos(struct mxs_lradc *lradc)
-{
-	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
-	mxs_lradc_reg_set(lradc, mxs_lradc_drive_x_plate(lradc), LRADC_CTRL0);
-
-	lradc->cur_plate = LRADC_SAMPLE_X;
-	mxs_lradc_map_channel(lradc, TOUCHSCREEN_VCHANNEL1, TS_CH_YP);
-	mxs_lradc_setup_ts_channel(lradc, TOUCHSCREEN_VCHANNEL1);
-}
-
-/*
- *   YP(+)--+-------------+
- *          |             |--+
- *          |             |  |
- *   YM(-)--+-------------+  |
- *            +--------------+
- *            |              |
- *         XP(open)        XM(meas)
- *
- * (+) means here 1.85 V
- * (-) means here GND
- */
-static void mxs_lradc_prepare_y_pos(struct mxs_lradc *lradc)
-{
-	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
-	mxs_lradc_reg_set(lradc, mxs_lradc_drive_y_plate(lradc), LRADC_CTRL0);
-
-	lradc->cur_plate = LRADC_SAMPLE_Y;
-	mxs_lradc_map_channel(lradc, TOUCHSCREEN_VCHANNEL1, TS_CH_XM);
-	mxs_lradc_setup_ts_channel(lradc, TOUCHSCREEN_VCHANNEL1);
-}
-
-/*
- *    YP(+)--+-------------+
- *           |             |--+
- *           |             |  |
- * YM(meas)--+-------------+  |
- *             +--------------+
- *             |              |
- *          XP(meas)        XM(-)
- *
- * (+) means here 1.85 V
- * (-) means here GND
- */
-static void mxs_lradc_prepare_pressure(struct mxs_lradc *lradc)
-{
-	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
-	mxs_lradc_reg_set(lradc, mxs_lradc_drive_pressure(lradc), LRADC_CTRL0);
-
-	lradc->cur_plate = LRADC_SAMPLE_PRESSURE;
-	mxs_lradc_map_channel(lradc, TOUCHSCREEN_VCHANNEL1, TS_CH_YM);
-	mxs_lradc_map_channel(lradc, TOUCHSCREEN_VCHANNEL2, TS_CH_XP);
-	mxs_lradc_setup_ts_pressure(lradc, TOUCHSCREEN_VCHANNEL2,
-				    TOUCHSCREEN_VCHANNEL1);
-}
-
-static void mxs_lradc_enable_touch_detection(struct mxs_lradc *lradc)
-{
-	mxs_lradc_setup_touch_detection(lradc);
-
-	lradc->cur_plate = LRADC_TOUCH;
-	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ |
-			    LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1);
-	mxs_lradc_reg_set(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1);
-}
-
-static void mxs_lradc_start_touch_event(struct mxs_lradc *lradc)
-{
-	mxs_lradc_reg_clear(lradc,
-			    LRADC_CTRL1_TOUCH_DETECT_IRQ_EN,
-			    LRADC_CTRL1);
-	mxs_lradc_reg_set(lradc,
-			  LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1),
-			  LRADC_CTRL1);
-	/*
-	 * start with the Y-pos, because it uses nearly the same plate
-	 * settings like the touch detection
-	 */
-	mxs_lradc_prepare_y_pos(lradc);
-}
-
-static void mxs_lradc_report_ts_event(struct mxs_lradc *lradc)
-{
-	input_report_abs(lradc->ts_input, ABS_X, lradc->ts_x_pos);
-	input_report_abs(lradc->ts_input, ABS_Y, lradc->ts_y_pos);
-	input_report_abs(lradc->ts_input, ABS_PRESSURE, lradc->ts_pressure);
-	input_report_key(lradc->ts_input, BTN_TOUCH, 1);
-	input_sync(lradc->ts_input);
-}
-
-static void mxs_lradc_complete_touch_event(struct mxs_lradc *lradc)
-{
-	mxs_lradc_setup_touch_detection(lradc);
-	lradc->cur_plate = LRADC_SAMPLE_VALID;
-	/*
-	 * start a dummy conversion to burn time to settle the signals
-	 * note: we are not interested in the conversion's value
-	 */
-	mxs_lradc_reg_wrt(lradc, 0, LRADC_CH(TOUCHSCREEN_VCHANNEL1));
-	mxs_lradc_reg_clear(lradc,
-			    LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
-			    LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2),
-			    LRADC_CTRL1);
-	mxs_lradc_reg_wrt(
-		    lradc,
-		    LRADC_DELAY_TRIGGER(1 << TOUCHSCREEN_VCHANNEL1) |
-		    LRADC_DELAY_KICK | LRADC_DELAY_DELAY(10), /* waste 5 ms */
-		    LRADC_DELAY(2));
-}
-
-/*
- * in order to avoid false measurements, report only samples where
- * the surface is still touched after the position measurement
- */
-static void mxs_lradc_finish_touch_event(struct mxs_lradc *lradc, bool valid)
-{
-	/* if it is still touched, report the sample */
-	if (valid && mxs_lradc_check_touch_event(lradc)) {
-		lradc->ts_valid = true;
-		mxs_lradc_report_ts_event(lradc);
-	}
-
-	/* if it is even still touched, continue with the next measurement */
-	if (mxs_lradc_check_touch_event(lradc)) {
-		mxs_lradc_prepare_y_pos(lradc);
-		return;
-	}
-
-	if (lradc->ts_valid) {
-		/* signal the release */
-		lradc->ts_valid = false;
-		input_report_key(lradc->ts_input, BTN_TOUCH, 0);
-		input_sync(lradc->ts_input);
-	}
-
-	/* if it is released, wait for the next touch via IRQ */
-	lradc->cur_plate = LRADC_TOUCH;
-	mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(2));
-	mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(3));
-	mxs_lradc_reg_clear(lradc,
-			    LRADC_CTRL1_TOUCH_DETECT_IRQ |
-			    LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1) |
-			    LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1),
-			    LRADC_CTRL1);
-	mxs_lradc_reg_set(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1);
-}
-
-/* touchscreen's state machine */
-static void mxs_lradc_handle_touch(struct mxs_lradc *lradc)
-{
-	switch (lradc->cur_plate) {
-	case LRADC_TOUCH:
-		if (mxs_lradc_check_touch_event(lradc))
-			mxs_lradc_start_touch_event(lradc);
-		mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ,
-				    LRADC_CTRL1);
-		return;
-
-	case LRADC_SAMPLE_Y:
-		lradc->ts_y_pos =
-		    mxs_lradc_read_raw_channel(lradc,
-					       TOUCHSCREEN_VCHANNEL1);
-		mxs_lradc_prepare_x_pos(lradc);
-		return;
-
-	case LRADC_SAMPLE_X:
-		lradc->ts_x_pos =
-		    mxs_lradc_read_raw_channel(lradc,
-					       TOUCHSCREEN_VCHANNEL1);
-		mxs_lradc_prepare_pressure(lradc);
-		return;
-
-	case LRADC_SAMPLE_PRESSURE:
-		lradc->ts_pressure =
-		    mxs_lradc_read_ts_pressure(lradc,
-					       TOUCHSCREEN_VCHANNEL2,
-					       TOUCHSCREEN_VCHANNEL1);
-		mxs_lradc_complete_touch_event(lradc);
-		return;
-
-	case LRADC_SAMPLE_VALID:
-		mxs_lradc_finish_touch_event(lradc, 1);
-		break;
-	}
-}
-
-/*
- * Raw I/O operations
- */
-static int mxs_lradc_read_single(struct iio_dev *iio_dev, int chan, int *val)
-{
-	struct mxs_lradc *lradc = iio_priv(iio_dev);
-	int ret;
-
-	/*
-	 * See if there is no buffered operation in progress. If there is, simply
-	 * bail out. This can be improved to support both buffered and raw IO at
-	 * the same time, yet the code becomes horribly complicated. Therefore I
-	 * applied KISS principle here.
-	 */
-	ret = mutex_trylock(&lradc->lock);
-	if (!ret)
-		return -EBUSY;
-
-	reinit_completion(&lradc->completion);
-
-	/*
-	 * No buffered operation in progress, map the channel and trigger it.
-	 * Virtual channel 0 is always used here as the others are always not
-	 * used if doing raw sampling.
-	 */
-	if (lradc->soc == IMX28_LRADC)
-		mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0),
-				    LRADC_CTRL1);
-	mxs_lradc_reg_clear(lradc, 0x1, LRADC_CTRL0);
-
-	/* Enable / disable the divider per requirement */
-	if (test_bit(chan, &lradc->is_divided))
-		mxs_lradc_reg_set(lradc,
-				  1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
-				  LRADC_CTRL2);
-	else
-		mxs_lradc_reg_clear(lradc,
-				    1 << LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET,
-				    LRADC_CTRL2);
-
-	/* Clean the slot's previous content, then set new one. */
-	mxs_lradc_reg_clear(lradc, LRADC_CTRL4_LRADCSELECT_MASK(0),
-			    LRADC_CTRL4);
-	mxs_lradc_reg_set(lradc, chan, LRADC_CTRL4);
-
-	mxs_lradc_reg_wrt(lradc, 0, LRADC_CH(0));
-
-	/* Enable the IRQ and start sampling the channel. */
-	mxs_lradc_reg_set(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1);
-	mxs_lradc_reg_set(lradc, BIT(0), LRADC_CTRL0);
-
-	/* Wait for completion on the channel, 1 second max. */
-	ret = wait_for_completion_killable_timeout(&lradc->completion, HZ);
-	if (!ret)
-		ret = -ETIMEDOUT;
-	if (ret < 0)
-		goto err;
-
-	/* Read the data. */
-	*val = readl(lradc->base + LRADC_CH(0)) & LRADC_CH_VALUE_MASK;
-	ret = IIO_VAL_INT;
-
-err:
-	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_LRADC_IRQ_EN(0), LRADC_CTRL1);
-
-	mutex_unlock(&lradc->lock);
-
-	return ret;
-}
-
-static int mxs_lradc_read_temp(struct iio_dev *iio_dev, int *val)
-{
-	int ret, min, max;
-
-	ret = mxs_lradc_read_single(iio_dev, 8, &min);
-	if (ret != IIO_VAL_INT)
-		return ret;
-
-	ret = mxs_lradc_read_single(iio_dev, 9, &max);
-	if (ret != IIO_VAL_INT)
-		return ret;
-
-	*val = max - min;
-
-	return IIO_VAL_INT;
-}
-
-static int mxs_lradc_read_raw(struct iio_dev *iio_dev,
-			      const struct iio_chan_spec *chan,
-			      int *val, int *val2, long m)
-{
-	struct mxs_lradc *lradc = iio_priv(iio_dev);
-
-	switch (m) {
-	case IIO_CHAN_INFO_RAW:
-		if (chan->type == IIO_TEMP)
-			return mxs_lradc_read_temp(iio_dev, val);
-
-		return mxs_lradc_read_single(iio_dev, chan->channel, val);
-
-	case IIO_CHAN_INFO_SCALE:
-		if (chan->type == IIO_TEMP) {
-			/*
-			 * From the datasheet, we have to multiply by 1.012 and
-			 * divide by 4
-			 */
-			*val = 0;
-			*val2 = 253000;
-			return IIO_VAL_INT_PLUS_MICRO;
-		}
-
-		*val = lradc->vref_mv[chan->channel];
-		*val2 = chan->scan_type.realbits -
-			test_bit(chan->channel, &lradc->is_divided);
-		return IIO_VAL_FRACTIONAL_LOG2;
-
-	case IIO_CHAN_INFO_OFFSET:
-		if (chan->type == IIO_TEMP) {
-			/*
-			 * The calculated value from the ADC is in Kelvin, we
-			 * want Celsius for hwmon so the offset is -273.15
-			 * The offset is applied before scaling so it is
-			 * actually -213.15 * 4 / 1.012 = -1079.644268
-			 */
-			*val = -1079;
-			*val2 = 644268;
-
-			return IIO_VAL_INT_PLUS_MICRO;
-		}
-
-		return -EINVAL;
-
-	default:
-		break;
-	}
-
-	return -EINVAL;
-}
-
-static int mxs_lradc_write_raw(struct iio_dev *iio_dev,
-			       const struct iio_chan_spec *chan,
-			       int val, int val2, long m)
-{
-	struct mxs_lradc *lradc = iio_priv(iio_dev);
-	struct mxs_lradc_scale *scale_avail =
-			lradc->scale_avail[chan->channel];
-	int ret;
-
-	ret = mutex_trylock(&lradc->lock);
-	if (!ret)
-		return -EBUSY;
-
-	switch (m) {
-	case IIO_CHAN_INFO_SCALE:
-		ret = -EINVAL;
-		if (val == scale_avail[MXS_LRADC_DIV_DISABLED].integer &&
-		    val2 == scale_avail[MXS_LRADC_DIV_DISABLED].nano) {
-			/* divider by two disabled */
-			clear_bit(chan->channel, &lradc->is_divided);
-			ret = 0;
-		} else if (val == scale_avail[MXS_LRADC_DIV_ENABLED].integer &&
-			   val2 == scale_avail[MXS_LRADC_DIV_ENABLED].nano) {
-			/* divider by two enabled */
-			set_bit(chan->channel, &lradc->is_divided);
-			ret = 0;
-		}
-
-		break;
-	default:
-		ret = -EINVAL;
-		break;
-	}
-
-	mutex_unlock(&lradc->lock);
-
-	return ret;
-}
-
-static int mxs_lradc_write_raw_get_fmt(struct iio_dev *iio_dev,
-				       const struct iio_chan_spec *chan,
-				       long m)
-{
-	return IIO_VAL_INT_PLUS_NANO;
-}
-
-static ssize_t mxs_lradc_show_scale_available_ch(struct device *dev,
-						 struct device_attribute *attr,
-						 char *buf,
-						 int ch)
-{
-	struct iio_dev *iio = dev_to_iio_dev(dev);
-	struct mxs_lradc *lradc = iio_priv(iio);
-	int i, len = 0;
-
-	for (i = 0; i < ARRAY_SIZE(lradc->scale_avail[ch]); i++)
-		len += sprintf(buf + len, "%u.%09u ",
-			       lradc->scale_avail[ch][i].integer,
-			       lradc->scale_avail[ch][i].nano);
-
-	len += sprintf(buf + len, "\n");
-
-	return len;
-}
-
-static ssize_t mxs_lradc_show_scale_available(struct device *dev,
-					      struct device_attribute *attr,
-					      char *buf)
-{
-	struct iio_dev_attr *iio_attr = to_iio_dev_attr(attr);
-
-	return mxs_lradc_show_scale_available_ch(dev, attr, buf,
-						 iio_attr->address);
-}
-
-#define SHOW_SCALE_AVAILABLE_ATTR(ch)					\
-static IIO_DEVICE_ATTR(in_voltage##ch##_scale_available, S_IRUGO,	\
-		       mxs_lradc_show_scale_available, NULL, ch)
-
-SHOW_SCALE_AVAILABLE_ATTR(0);
-SHOW_SCALE_AVAILABLE_ATTR(1);
-SHOW_SCALE_AVAILABLE_ATTR(2);
-SHOW_SCALE_AVAILABLE_ATTR(3);
-SHOW_SCALE_AVAILABLE_ATTR(4);
-SHOW_SCALE_AVAILABLE_ATTR(5);
-SHOW_SCALE_AVAILABLE_ATTR(6);
-SHOW_SCALE_AVAILABLE_ATTR(7);
-SHOW_SCALE_AVAILABLE_ATTR(10);
-SHOW_SCALE_AVAILABLE_ATTR(11);
-SHOW_SCALE_AVAILABLE_ATTR(12);
-SHOW_SCALE_AVAILABLE_ATTR(13);
-SHOW_SCALE_AVAILABLE_ATTR(14);
-SHOW_SCALE_AVAILABLE_ATTR(15);
-
-static struct attribute *mxs_lradc_attributes[] = {
-	&iio_dev_attr_in_voltage0_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage1_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage2_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage3_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage4_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage5_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage6_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage7_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage10_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage11_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage12_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage13_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage14_scale_available.dev_attr.attr,
-	&iio_dev_attr_in_voltage15_scale_available.dev_attr.attr,
-	NULL
-};
-
-static const struct attribute_group mxs_lradc_attribute_group = {
-	.attrs = mxs_lradc_attributes,
-};
-
-static const struct iio_info mxs_lradc_iio_info = {
-	.driver_module		= THIS_MODULE,
-	.read_raw		= mxs_lradc_read_raw,
-	.write_raw		= mxs_lradc_write_raw,
-	.write_raw_get_fmt	= mxs_lradc_write_raw_get_fmt,
-	.attrs			= &mxs_lradc_attribute_group,
-};
-
-static int mxs_lradc_ts_open(struct input_dev *dev)
-{
-	struct mxs_lradc *lradc = input_get_drvdata(dev);
-
-	/* Enable the touch-detect circuitry. */
-	mxs_lradc_enable_touch_detection(lradc);
-
-	return 0;
-}
-
-static void mxs_lradc_disable_ts(struct mxs_lradc *lradc)
-{
-	/* stop all interrupts from firing */
-	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN |
-		LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL1) |
-		LRADC_CTRL1_LRADC_IRQ_EN(TOUCHSCREEN_VCHANNEL2), LRADC_CTRL1);
-
-	/* Power-down touchscreen touch-detect circuitry. */
-	mxs_lradc_reg_clear(lradc, mxs_lradc_plate_mask(lradc), LRADC_CTRL0);
-}
-
-static void mxs_lradc_ts_close(struct input_dev *dev)
-{
-	struct mxs_lradc *lradc = input_get_drvdata(dev);
-
-	mxs_lradc_disable_ts(lradc);
-}
-
-static int mxs_lradc_ts_register(struct mxs_lradc *lradc)
-{
-	struct input_dev *input;
-	struct device *dev = lradc->dev;
-	int ret;
-
-	if (!lradc->use_touchscreen)
-		return 0;
-
-	input = input_allocate_device();
-	if (!input)
-		return -ENOMEM;
-
-	input->name = DRIVER_NAME;
-	input->id.bustype = BUS_HOST;
-	input->dev.parent = dev;
-	input->open = mxs_lradc_ts_open;
-	input->close = mxs_lradc_ts_close;
-
-	__set_bit(EV_ABS, input->evbit);
-	__set_bit(EV_KEY, input->evbit);
-	__set_bit(BTN_TOUCH, input->keybit);
-	input_set_abs_params(input, ABS_X, 0, LRADC_SINGLE_SAMPLE_MASK, 0, 0);
-	input_set_abs_params(input, ABS_Y, 0, LRADC_SINGLE_SAMPLE_MASK, 0, 0);
-	input_set_abs_params(input, ABS_PRESSURE, 0, LRADC_SINGLE_SAMPLE_MASK,
-			     0, 0);
-
-	lradc->ts_input = input;
-	input_set_drvdata(input, lradc);
-	ret = input_register_device(input);
-	if (ret)
-		input_free_device(lradc->ts_input);
-
-	return ret;
-}
-
-static void mxs_lradc_ts_unregister(struct mxs_lradc *lradc)
-{
-	if (!lradc->use_touchscreen)
-		return;
-
-	mxs_lradc_disable_ts(lradc);
-	input_unregister_device(lradc->ts_input);
-}
-
-/*
- * IRQ Handling
- */
-static irqreturn_t mxs_lradc_handle_irq(int irq, void *data)
-{
-	struct iio_dev *iio = data;
-	struct mxs_lradc *lradc = iio_priv(iio);
-	unsigned long reg = readl(lradc->base + LRADC_CTRL1);
-	u32 clr_irq = mxs_lradc_irq_mask(lradc);
-	const u32 ts_irq_mask =
-		LRADC_CTRL1_TOUCH_DETECT_IRQ |
-		LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
-		LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2);
-
-	if (!(reg & mxs_lradc_irq_mask(lradc)))
-		return IRQ_NONE;
-
-	if (lradc->use_touchscreen && (reg & ts_irq_mask)) {
-		mxs_lradc_handle_touch(lradc);
-
-		/* Make sure we don't clear the next conversion's interrupt. */
-		clr_irq &= ~(LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL1) |
-				LRADC_CTRL1_LRADC_IRQ(TOUCHSCREEN_VCHANNEL2));
-	}
-
-	if (iio_buffer_enabled(iio)) {
-		if (reg & lradc->buffer_vchans)
-			iio_trigger_poll(iio->trig);
-	} else if (reg & LRADC_CTRL1_LRADC_IRQ(0)) {
-		complete(&lradc->completion);
-	}
-
-	mxs_lradc_reg_clear(lradc, reg & clr_irq, LRADC_CTRL1);
-
-	return IRQ_HANDLED;
-}
-
-/*
- * Trigger handling
- */
-static irqreturn_t mxs_lradc_trigger_handler(int irq, void *p)
-{
-	struct iio_poll_func *pf = p;
-	struct iio_dev *iio = pf->indio_dev;
-	struct mxs_lradc *lradc = iio_priv(iio);
-	const u32 chan_value = LRADC_CH_ACCUMULATE |
-		((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET);
-	unsigned int i, j = 0;
-
-	for_each_set_bit(i, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
-		lradc->buffer[j] = readl(lradc->base + LRADC_CH(j));
-		mxs_lradc_reg_wrt(lradc, chan_value, LRADC_CH(j));
-		lradc->buffer[j] &= LRADC_CH_VALUE_MASK;
-		lradc->buffer[j] /= LRADC_DELAY_TIMER_LOOP;
-		j++;
-	}
-
-	iio_push_to_buffers_with_timestamp(iio, lradc->buffer, pf->timestamp);
-
-	iio_trigger_notify_done(iio->trig);
-
-	return IRQ_HANDLED;
-}
-
-static int mxs_lradc_configure_trigger(struct iio_trigger *trig, bool state)
-{
-	struct iio_dev *iio = iio_trigger_get_drvdata(trig);
-	struct mxs_lradc *lradc = iio_priv(iio);
-	const u32 st = state ? STMP_OFFSET_REG_SET : STMP_OFFSET_REG_CLR;
-
-	mxs_lradc_reg_wrt(lradc, LRADC_DELAY_KICK, LRADC_DELAY(0) + st);
-
-	return 0;
-}
-
-static const struct iio_trigger_ops mxs_lradc_trigger_ops = {
-	.owner = THIS_MODULE,
-	.set_trigger_state = &mxs_lradc_configure_trigger,
-};
-
-static int mxs_lradc_trigger_init(struct iio_dev *iio)
-{
-	int ret;
-	struct iio_trigger *trig;
-	struct mxs_lradc *lradc = iio_priv(iio);
-
-	trig = iio_trigger_alloc("%s-dev%i", iio->name, iio->id);
-	if (!trig)
-		return -ENOMEM;
-
-	trig->dev.parent = lradc->dev;
-	iio_trigger_set_drvdata(trig, iio);
-	trig->ops = &mxs_lradc_trigger_ops;
-
-	ret = iio_trigger_register(trig);
-	if (ret) {
-		iio_trigger_free(trig);
-		return ret;
-	}
-
-	lradc->trig = trig;
-
-	return 0;
-}
-
-static void mxs_lradc_trigger_remove(struct iio_dev *iio)
-{
-	struct mxs_lradc *lradc = iio_priv(iio);
-
-	iio_trigger_unregister(lradc->trig);
-	iio_trigger_free(lradc->trig);
-}
-
-static int mxs_lradc_buffer_preenable(struct iio_dev *iio)
-{
-	struct mxs_lradc *lradc = iio_priv(iio);
-	int ret = 0, chan, ofs = 0;
-	unsigned long enable = 0;
-	u32 ctrl4_set = 0;
-	u32 ctrl4_clr = 0;
-	u32 ctrl1_irq = 0;
-	const u32 chan_value = LRADC_CH_ACCUMULATE |
-		((LRADC_DELAY_TIMER_LOOP - 1) << LRADC_CH_NUM_SAMPLES_OFFSET);
-	const int len = bitmap_weight(iio->active_scan_mask,
-			LRADC_MAX_TOTAL_CHANS);
-
-	if (!len)
-		return -EINVAL;
-
-	/*
-	 * Lock the driver so raw access can not be done during buffered
-	 * operation. This simplifies the code a lot.
-	 */
-	ret = mutex_trylock(&lradc->lock);
-	if (!ret)
-		return -EBUSY;
-
-	lradc->buffer = kmalloc_array(len, sizeof(*lradc->buffer), GFP_KERNEL);
-	if (!lradc->buffer) {
-		ret = -ENOMEM;
-		goto err_mem;
-	}
-
-	if (lradc->soc == IMX28_LRADC)
-		mxs_lradc_reg_clear(
-			lradc,
-			lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
-			LRADC_CTRL1);
-	mxs_lradc_reg_clear(lradc, lradc->buffer_vchans, LRADC_CTRL0);
-
-	for_each_set_bit(chan, iio->active_scan_mask, LRADC_MAX_TOTAL_CHANS) {
-		ctrl4_set |= chan << LRADC_CTRL4_LRADCSELECT_OFFSET(ofs);
-		ctrl4_clr |= LRADC_CTRL4_LRADCSELECT_MASK(ofs);
-		ctrl1_irq |= LRADC_CTRL1_LRADC_IRQ_EN(ofs);
-		mxs_lradc_reg_wrt(lradc, chan_value, LRADC_CH(ofs));
-		bitmap_set(&enable, ofs, 1);
-		ofs++;
-	}
-
-	mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK |
-			    LRADC_DELAY_KICK, LRADC_DELAY(0));
-	mxs_lradc_reg_clear(lradc, ctrl4_clr, LRADC_CTRL4);
-	mxs_lradc_reg_set(lradc, ctrl4_set, LRADC_CTRL4);
-	mxs_lradc_reg_set(lradc, ctrl1_irq, LRADC_CTRL1);
-	mxs_lradc_reg_set(lradc, enable << LRADC_DELAY_TRIGGER_LRADCS_OFFSET,
-			  LRADC_DELAY(0));
-
-	return 0;
-
-err_mem:
-	mutex_unlock(&lradc->lock);
-	return ret;
-}
-
-static int mxs_lradc_buffer_postdisable(struct iio_dev *iio)
-{
-	struct mxs_lradc *lradc = iio_priv(iio);
-
-	mxs_lradc_reg_clear(lradc, LRADC_DELAY_TRIGGER_LRADCS_MASK |
-			    LRADC_DELAY_KICK, LRADC_DELAY(0));
-
-	mxs_lradc_reg_clear(lradc, lradc->buffer_vchans, LRADC_CTRL0);
-	if (lradc->soc == IMX28_LRADC)
-		mxs_lradc_reg_clear(
-			lradc,
-			lradc->buffer_vchans << LRADC_CTRL1_LRADC_IRQ_EN_OFFSET,
-			LRADC_CTRL1);
-
-	kfree(lradc->buffer);
-	mutex_unlock(&lradc->lock);
-
-	return 0;
-}
-
-static bool mxs_lradc_validate_scan_mask(struct iio_dev *iio,
-					 const unsigned long *mask)
-{
-	struct mxs_lradc *lradc = iio_priv(iio);
-	const int map_chans = bitmap_weight(mask, LRADC_MAX_TOTAL_CHANS);
-	int rsvd_chans = 0;
-	unsigned long rsvd_mask = 0;
-
-	if (lradc->use_touchbutton)
-		rsvd_mask |= CHAN_MASK_TOUCHBUTTON;
-	if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_4WIRE)
-		rsvd_mask |= CHAN_MASK_TOUCHSCREEN_4WIRE;
-	if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE)
-		rsvd_mask |= CHAN_MASK_TOUCHSCREEN_5WIRE;
-
-	if (lradc->use_touchbutton)
-		rsvd_chans++;
-	if (lradc->use_touchscreen)
-		rsvd_chans += 2;
-
-	/* Test for attempts to map channels with special mode of operation. */
-	if (bitmap_intersects(mask, &rsvd_mask, LRADC_MAX_TOTAL_CHANS))
-		return false;
-
-	/* Test for attempts to map more channels then available slots. */
-	if (map_chans + rsvd_chans > LRADC_MAX_MAPPED_CHANS)
-		return false;
-
-	return true;
-}
-
-static const struct iio_buffer_setup_ops mxs_lradc_buffer_ops = {
-	.preenable = &mxs_lradc_buffer_preenable,
-	.postenable = &iio_triggered_buffer_postenable,
-	.predisable = &iio_triggered_buffer_predisable,
-	.postdisable = &mxs_lradc_buffer_postdisable,
-	.validate_scan_mask = &mxs_lradc_validate_scan_mask,
-};
-
-/*
- * Driver initialization
- */
-
-#define MXS_ADC_CHAN(idx, chan_type, name) {			\
-	.type = (chan_type),					\
-	.indexed = 1,						\
-	.scan_index = (idx),					\
-	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
-			      BIT(IIO_CHAN_INFO_SCALE),		\
-	.channel = (idx),					\
-	.address = (idx),					\
-	.scan_type = {						\
-		.sign = 'u',					\
-		.realbits = LRADC_RESOLUTION,			\
-		.storagebits = 32,				\
-	},							\
-	.datasheet_name = (name),				\
-}
-
-static const struct iio_chan_spec mx23_lradc_chan_spec[] = {
-	MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"),
-	MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"),
-	MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"),
-	MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"),
-	MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"),
-	MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"),
-	MXS_ADC_CHAN(6, IIO_VOLTAGE, "VDDIO"),
-	MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"),
-	/* Combined Temperature sensors */
-	{
-		.type = IIO_TEMP,
-		.indexed = 1,
-		.scan_index = 8,
-		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
-				      BIT(IIO_CHAN_INFO_OFFSET) |
-				      BIT(IIO_CHAN_INFO_SCALE),
-		.channel = 8,
-		.scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
-		.datasheet_name = "TEMP_DIE",
-	},
-	/* Hidden channel to keep indexes */
-	{
-		.type = IIO_TEMP,
-		.indexed = 1,
-		.scan_index = -1,
-		.channel = 9,
-	},
-	MXS_ADC_CHAN(10, IIO_VOLTAGE, NULL),
-	MXS_ADC_CHAN(11, IIO_VOLTAGE, NULL),
-	MXS_ADC_CHAN(12, IIO_VOLTAGE, "USB_DP"),
-	MXS_ADC_CHAN(13, IIO_VOLTAGE, "USB_DN"),
-	MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"),
-	MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"),
-};
-
-static const struct iio_chan_spec mx28_lradc_chan_spec[] = {
-	MXS_ADC_CHAN(0, IIO_VOLTAGE, "LRADC0"),
-	MXS_ADC_CHAN(1, IIO_VOLTAGE, "LRADC1"),
-	MXS_ADC_CHAN(2, IIO_VOLTAGE, "LRADC2"),
-	MXS_ADC_CHAN(3, IIO_VOLTAGE, "LRADC3"),
-	MXS_ADC_CHAN(4, IIO_VOLTAGE, "LRADC4"),
-	MXS_ADC_CHAN(5, IIO_VOLTAGE, "LRADC5"),
-	MXS_ADC_CHAN(6, IIO_VOLTAGE, "LRADC6"),
-	MXS_ADC_CHAN(7, IIO_VOLTAGE, "VBATT"),
-	/* Combined Temperature sensors */
-	{
-		.type = IIO_TEMP,
-		.indexed = 1,
-		.scan_index = 8,
-		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
-				      BIT(IIO_CHAN_INFO_OFFSET) |
-				      BIT(IIO_CHAN_INFO_SCALE),
-		.channel = 8,
-		.scan_type = {.sign = 'u', .realbits = 18, .storagebits = 32,},
-		.datasheet_name = "TEMP_DIE",
-	},
-	/* Hidden channel to keep indexes */
-	{
-		.type = IIO_TEMP,
-		.indexed = 1,
-		.scan_index = -1,
-		.channel = 9,
-	},
-	MXS_ADC_CHAN(10, IIO_VOLTAGE, "VDDIO"),
-	MXS_ADC_CHAN(11, IIO_VOLTAGE, "VTH"),
-	MXS_ADC_CHAN(12, IIO_VOLTAGE, "VDDA"),
-	MXS_ADC_CHAN(13, IIO_VOLTAGE, "VDDD"),
-	MXS_ADC_CHAN(14, IIO_VOLTAGE, "VBG"),
-	MXS_ADC_CHAN(15, IIO_VOLTAGE, "VDD5V"),
-};
-
-static int mxs_lradc_hw_init(struct mxs_lradc *lradc)
-{
-	/* The ADC always uses DELAY CHANNEL 0. */
-	const u32 adc_cfg =
-		(1 << (LRADC_DELAY_TRIGGER_DELAYS_OFFSET + 0)) |
-		(LRADC_DELAY_TIMER_PER << LRADC_DELAY_DELAY_OFFSET);
-
-	int ret = stmp_reset_block(lradc->base);
-
-	if (ret)
-		return ret;
-
-	/* Configure DELAY CHANNEL 0 for generic ADC sampling. */
-	mxs_lradc_reg_wrt(lradc, adc_cfg, LRADC_DELAY(0));
-
-	/* Disable remaining DELAY CHANNELs */
-	mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(1));
-	mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(2));
-	mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(3));
-
-	/* Configure the touchscreen type */
-	if (lradc->soc == IMX28_LRADC) {
-		mxs_lradc_reg_clear(lradc, LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
-				    LRADC_CTRL0);
-
-	if (lradc->use_touchscreen == MXS_LRADC_TOUCHSCREEN_5WIRE)
-		mxs_lradc_reg_set(lradc, LRADC_CTRL0_MX28_TOUCH_SCREEN_TYPE,
-				  LRADC_CTRL0);
-	}
-
-	/* Start internal temperature sensing. */
-	mxs_lradc_reg_wrt(lradc, 0, LRADC_CTRL2);
-
-	return 0;
-}
-
-static void mxs_lradc_hw_stop(struct mxs_lradc *lradc)
-{
-	int i;
-
-	mxs_lradc_reg_clear(lradc, mxs_lradc_irq_en_mask(lradc), LRADC_CTRL1);
-
-	for (i = 0; i < LRADC_MAX_DELAY_CHANS; i++)
-		mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(i));
-}
-
-static const struct of_device_id mxs_lradc_dt_ids[] = {
-	{ .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
-	{ .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
-	{ /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
-
-static int mxs_lradc_probe_touchscreen(struct mxs_lradc *lradc,
-				       struct device_node *lradc_node)
-{
-	int ret;
-	u32 ts_wires = 0, adapt;
-
-	ret = of_property_read_u32(lradc_node, "fsl,lradc-touchscreen-wires",
-				   &ts_wires);
-	if (ret)
-		return -ENODEV; /* touchscreen feature disabled */
-
-	switch (ts_wires) {
-	case 4:
-		lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_4WIRE;
-		break;
-	case 5:
-		if (lradc->soc == IMX28_LRADC) {
-			lradc->use_touchscreen = MXS_LRADC_TOUCHSCREEN_5WIRE;
-			break;
-		}
-		/* fall through an error message for i.MX23 */
-	default:
-		dev_err(lradc->dev,
-			"Unsupported number of touchscreen wires (%d)\n",
-			ts_wires);
-		return -EINVAL;
-	}
-
-	if (of_property_read_u32(lradc_node, "fsl,ave-ctrl", &adapt)) {
-		lradc->over_sample_cnt = 4;
-	} else {
-		if (adapt < 1 || adapt > 32) {
-			dev_err(lradc->dev, "Invalid sample count (%u)\n",
-				adapt);
-			return -EINVAL;
-		}
-		lradc->over_sample_cnt = adapt;
-	}
-
-	if (of_property_read_u32(lradc_node, "fsl,ave-delay", &adapt)) {
-		lradc->over_sample_delay = 2;
-	} else {
-		if (adapt < 2 || adapt > LRADC_DELAY_DELAY_MASK + 1) {
-			dev_err(lradc->dev, "Invalid sample delay (%u)\n",
-				adapt);
-			return -EINVAL;
-		}
-		lradc->over_sample_delay = adapt;
-	}
-
-	if (of_property_read_u32(lradc_node, "fsl,settling", &adapt)) {
-		lradc->settling_delay = 10;
-	} else {
-		if (adapt < 1 || adapt > LRADC_DELAY_DELAY_MASK) {
-			dev_err(lradc->dev, "Invalid settling delay (%u)\n",
-				adapt);
-			return -EINVAL;
-		}
-		lradc->settling_delay = adapt;
-	}
-
-	return 0;
-}
-
-static int mxs_lradc_probe(struct platform_device *pdev)
-{
-	const struct of_device_id *of_id =
-		of_match_device(mxs_lradc_dt_ids, &pdev->dev);
-	const struct mxs_lradc_of_config *of_cfg =
-		&mxs_lradc_of_config[(enum mxs_lradc_id)of_id->data];
-	struct device *dev = &pdev->dev;
-	struct device_node *node = dev->of_node;
-	struct mxs_lradc *lradc;
-	struct iio_dev *iio;
-	struct resource *iores;
-	int ret = 0, touch_ret;
-	int i, s;
-	u64 scale_uv;
-
-	/* Allocate the IIO device. */
-	iio = devm_iio_device_alloc(dev, sizeof(*lradc));
-	if (!iio) {
-		dev_err(dev, "Failed to allocate IIO device\n");
-		return -ENOMEM;
-	}
-
-	lradc = iio_priv(iio);
-	lradc->soc = (enum mxs_lradc_id)of_id->data;
-
-	/* Grab the memory area */
-	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	lradc->dev = &pdev->dev;
-	lradc->base = devm_ioremap_resource(dev, iores);
-	if (IS_ERR(lradc->base))
-		return PTR_ERR(lradc->base);
-
-	lradc->clk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(lradc->clk)) {
-		dev_err(dev, "Failed to get the delay unit clock\n");
-		return PTR_ERR(lradc->clk);
-	}
-	ret = clk_prepare_enable(lradc->clk);
-	if (ret != 0) {
-		dev_err(dev, "Failed to enable the delay unit clock\n");
-		return ret;
-	}
-
-	touch_ret = mxs_lradc_probe_touchscreen(lradc, node);
-
-	if (touch_ret == 0)
-		lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;
-	else
-		lradc->buffer_vchans = BUFFER_VCHANS_ALL;
-
-	/* Grab all IRQ sources */
-	for (i = 0; i < of_cfg->irq_count; i++) {
-		lradc->irq[i] = platform_get_irq(pdev, i);
-		if (lradc->irq[i] < 0) {
-			ret = lradc->irq[i];
-			goto err_clk;
-		}
-
-		ret = devm_request_irq(dev, lradc->irq[i],
-				       mxs_lradc_handle_irq, 0,
-				       of_cfg->irq_name[i], iio);
-		if (ret)
-			goto err_clk;
-	}
-
-	lradc->vref_mv = of_cfg->vref_mv;
-
-	platform_set_drvdata(pdev, iio);
-
-	init_completion(&lradc->completion);
-	mutex_init(&lradc->lock);
-
-	iio->name = pdev->name;
-	iio->dev.parent = &pdev->dev;
-	iio->info = &mxs_lradc_iio_info;
-	iio->modes = INDIO_DIRECT_MODE;
-	iio->masklength = LRADC_MAX_TOTAL_CHANS;
-
-	if (lradc->soc == IMX23_LRADC) {
-		iio->channels = mx23_lradc_chan_spec;
-		iio->num_channels = ARRAY_SIZE(mx23_lradc_chan_spec);
-	} else {
-		iio->channels = mx28_lradc_chan_spec;
-		iio->num_channels = ARRAY_SIZE(mx28_lradc_chan_spec);
-	}
-
-	ret = iio_triggered_buffer_setup(iio, &iio_pollfunc_store_time,
-					 &mxs_lradc_trigger_handler,
-					 &mxs_lradc_buffer_ops);
-	if (ret)
-		goto err_clk;
-
-	ret = mxs_lradc_trigger_init(iio);
-	if (ret)
-		goto err_trig;
-
-	/* Populate available ADC input ranges */
-	for (i = 0; i < LRADC_MAX_TOTAL_CHANS; i++) {
-		for (s = 0; s < ARRAY_SIZE(lradc->scale_avail[i]); s++) {
-			/*
-			 * [s=0] = optional divider by two disabled (default)
-			 * [s=1] = optional divider by two enabled
-			 *
-			 * The scale is calculated by doing:
-			 *   Vref >> (realbits - s)
-			 * which multiplies by two on the second component
-			 * of the array.
-			 */
-			scale_uv = ((u64)lradc->vref_mv[i] * 100000000) >>
-				   (LRADC_RESOLUTION - s);
-			lradc->scale_avail[i][s].nano =
-					do_div(scale_uv, 100000000) * 10;
-			lradc->scale_avail[i][s].integer = scale_uv;
-		}
-	}
-
-	/* Configure the hardware. */
-	ret = mxs_lradc_hw_init(lradc);
-	if (ret)
-		goto err_dev;
-
-	/* Register the touchscreen input device. */
-	if (touch_ret == 0) {
-		ret = mxs_lradc_ts_register(lradc);
-		if (ret)
-			goto err_ts_register;
-	}
-
-	/* Register IIO device. */
-	ret = iio_device_register(iio);
-	if (ret) {
-		dev_err(dev, "Failed to register IIO device\n");
-		goto err_ts;
-	}
-
-	return 0;
-
-err_ts:
-	mxs_lradc_ts_unregister(lradc);
-err_ts_register:
-	mxs_lradc_hw_stop(lradc);
-err_dev:
-	mxs_lradc_trigger_remove(iio);
-err_trig:
-	iio_triggered_buffer_cleanup(iio);
-err_clk:
-	clk_disable_unprepare(lradc->clk);
-	return ret;
-}
-
-static int mxs_lradc_remove(struct platform_device *pdev)
-{
-	struct iio_dev *iio = platform_get_drvdata(pdev);
-	struct mxs_lradc *lradc = iio_priv(iio);
-
-	iio_device_unregister(iio);
-	mxs_lradc_ts_unregister(lradc);
-	mxs_lradc_hw_stop(lradc);
-	mxs_lradc_trigger_remove(iio);
-	iio_triggered_buffer_cleanup(iio);
-
-	clk_disable_unprepare(lradc->clk);
-
-	return 0;
-}
-
-static struct platform_driver mxs_lradc_driver = {
-	.driver	= {
-		.name	= DRIVER_NAME,
-		.of_match_table = mxs_lradc_dt_ids,
-	},
-	.probe	= mxs_lradc_probe,
-	.remove	= mxs_lradc_remove,
-};
-
-module_platform_driver(mxs_lradc_driver);
-
-MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
-MODULE_DESCRIPTION("Freescale MXS LRADC driver");
-MODULE_LICENSE("GPL v2");
-MODULE_ALIAS("platform:" DRIVER_NAME);
-- 
1.9.1