[PATCH v5 2/3] mfd: add support for Allwinner SoCs ADC

Quentin Schulz
2016-09-08T14:28:36Z

The Allwinner SoCs all have an ADC that can also act as a touchscreen
controller and a thermal sensor. For now, only the ADC and the thermal
sensor drivers are probed by the MFD, the touchscreen controller support
will be added later.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
---

v5:
- correct mail address,

v4:
- rename files and variables from sunxi* to sun4i*,
- rename defines from SUNXI_* to SUN4I_* or SUN6I_*,
- remove TP in defines name,
- rename SUNXI_IRQ_* to SUN4I_GPADC_IRQ_* for consistency,
- use devm functions for regmap_add_irq_chip and mfd_add_devices,
- remove remove functions (now empty thanks to devm functions),

v3:
- use defines in regmap_irq instead of hard coded BITs,
- use of_device_id data field to chose which MFD cells to add considering
the compatible responsible of the MFD probe,
- remove useless initializations,
- disable all interrupts before adding them to regmap_irqchip,
- add goto error label in probe,
- correct wrapping in header license,
- move defines from IIO driver to header,
- use GENMASK to limit the size of the variable passed to a macro,
- prefix register BIT defines with the name of the register,
- reorder defines,

v2:
- add license headers,
- reorder alphabetically includes,
- add SUNXI_GPADC_ prefixes for defines,

drivers/mfd/Kconfig | 15 ++++
drivers/mfd/Makefile | 2 +
drivers/mfd/sun4i-gpadc-mfd.c | 174 ++++++++++++++++++++++++++++++++++++
include/linux/mfd/sun4i-gpadc-mfd.h | 94 +++++++++++++++++++
4 files changed, 285 insertions(+)
create mode 100644 drivers/mfd/sun4i-gpadc-mfd.c
create mode 100644 include/linux/mfd/sun4i-gpadc-mfd.h

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 1bcf601..95b3c3e 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -29,6 +29,21 @@ config MFD_ACT8945A
linear regulators, along with a complete ActivePath battery
charger.

+config MFD_SUN4I_GPADC
+ tristate "Allwinner sunxi platforms' GPADC MFD driver"
+ select MFD_CORE
+ select REGMAP_MMIO
+ depends on ARCH_SUNXI || COMPILE_TEST
+ help
+ Select this to get support for Allwinner SoCs (A10, A13 and A31) ADC.
+ This driver will only map the hardware interrupt and registers, you
+ have to select individual drivers based on this MFD to be able to use
+ the ADC or the thermal sensor. This will try to probe the ADC driver
+ sun4i-gpadc-iio and the hwmon driver iio_hwmon.
+
+ To compile this driver as a module, choose M here: the module will be
+ called sun4i-gpadc-mfd.
+
config MFD_AS3711
bool "AMS AS3711"
select MFD_CORE
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 42a66e1..3b964d7 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -205,3 +205,5 @@ 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_SUN4I_GPADC) += sun4i-gpadc-mfd.o
diff --git a/drivers/mfd/sun4i-gpadc-mfd.c b/drivers/mfd/sun4i-gpadc-mfd.c
new file mode 100644
index 0000000..b499545
--- /dev/null
+++ b/drivers/mfd/sun4i-gpadc-mfd.c
@@ -0,0 +1,174 @@
+/* ADC MFD core driver for sunxi platforms
+ *
+ * Copyright (c) 2016 Quentin Schulz <quentin.schulz@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/regmap.h>
+
+#include <linux/mfd/sun4i-gpadc-mfd.h>
+
+static struct resource adc_resources[] = {
+ {
+ .name = "FIFO_DATA_PENDING",
+ .start = SUN4I_GPADC_IRQ_FIFO_DATA,
+ .end = SUN4I_GPADC_IRQ_FIFO_DATA,
+ .flags = IORESOURCE_IRQ,
+ }, {
+ .name = "TEMP_DATA_PENDING",
+ .start = SUN4I_GPADC_IRQ_TEMP_DATA,
+ .end = SUN4I_GPADC_IRQ_TEMP_DATA,
+ .flags = IORESOURCE_IRQ,
+ },
+};
+
+static const struct regmap_irq sun4i_gpadc_mfd_regmap_irq[] = {
+ REGMAP_IRQ_REG(SUN4I_GPADC_IRQ_FIFO_DATA, 0,
+ SUN4I_GPADC_INT_FIFOC_TP_DATA_IRQ_EN),
+ REGMAP_IRQ_REG(SUN4I_GPADC_IRQ_TEMP_DATA, 0,
+ SUN4I_GPADC_INT_FIFOC_TEMP_IRQ_EN),
+};
+
+static const struct regmap_irq_chip sun4i_gpadc_mfd_regmap_irq_chip = {
+ .name = "sun4i_gpadc_mfd_irq_chip",
+ .status_base = SUN4I_GPADC_INT_FIFOS,
+ .ack_base = SUN4I_GPADC_INT_FIFOS,
+ .mask_base = SUN4I_GPADC_INT_FIFOC,
+ .init_ack_masked = true,
+ .mask_invert = true,
+ .irqs = sun4i_gpadc_mfd_regmap_irq,
+ .num_irqs = ARRAY_SIZE(sun4i_gpadc_mfd_regmap_irq),
+ .num_regs = 1,
+};
+
+static struct mfd_cell sun4i_gpadc_mfd_cells[] = {
+ {
+ .name = "sun4i-a10-gpadc-iio",
+ .resources = adc_resources,
+ .num_resources = ARRAY_SIZE(adc_resources),
+ }, {
+ .name = "iio_hwmon",
+ }
+};
+
+static struct mfd_cell sun5i_gpadc_mfd_cells[] = {
+ {
+ .name = "sun5i-a13-gpadc-iio",
+ .resources = adc_resources,
+ .num_resources = ARRAY_SIZE(adc_resources),
+ }, {
+ .name = "iio_hwmon",
+ },
+};
+
+static struct mfd_cell sun6i_gpadc_mfd_cells[] = {
+ {
+ .name = "sun6i-a31-gpadc-iio",
+ .resources = adc_resources,
+ .num_resources = ARRAY_SIZE(adc_resources),
+ }, {
+ .name = "iio_hwmon",
+ },
+};
+
+static const struct regmap_config sun4i_gpadc_mfd_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .fast_io = true,
+};
+
+static const struct of_device_id sun4i_gpadc_mfd_of_match[] = {
+ {
+ .compatible = "allwinner,sun4i-a10-ts",
+ .data = &sun4i_gpadc_mfd_cells,
+ }, {
+ .compatible = "allwinner,sun5i-a13-ts",
+ .data = &sun5i_gpadc_mfd_cells,
+ }, {
+ .compatible = "allwinner,sun6i-a31-ts",
+ .data = &sun6i_gpadc_mfd_cells,
+ }, { /* sentinel */ }
+};
+
+static int sun4i_gpadc_mfd_probe(struct platform_device *pdev)
+{
+ struct sun4i_gpadc_mfd_dev *mfd_dev;
+ struct resource *mem;
+ const struct of_device_id *of_id;
+ const struct mfd_cell *mfd_cells;
+ unsigned int irq;
+ int ret;
+
+ of_id = of_match_node(sun4i_gpadc_mfd_of_match, pdev->dev.of_node);
+ if (!of_id)
+ return -EINVAL;
+
+ mfd_dev = devm_kzalloc(&pdev->dev, sizeof(*mfd_dev), GFP_KERNEL);
+ if (!mfd_dev)
+ return -ENOMEM;
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ mfd_dev->regs = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(mfd_dev->regs))
+ return PTR_ERR(mfd_dev->regs);
+
+ mfd_dev->dev = &pdev->dev;
+ dev_set_drvdata(mfd_dev->dev, mfd_dev);
+
+ mfd_dev->regmap = devm_regmap_init_mmio(mfd_dev->dev, mfd_dev->regs,
+ &sun4i_gpadc_mfd_regmap_config);
+ if (IS_ERR(mfd_dev->regmap)) {
+ ret = PTR_ERR(mfd_dev->regmap);
+ dev_err(&pdev->dev, "failed to init regmap: %d\n", ret);
+ return ret;
+ }
+
+ /* Disable all interrupts */
+ regmap_write(mfd_dev->regmap, SUN4I_GPADC_INT_FIFOC, 0);
+
+ irq = platform_get_irq(pdev, 0);
+ ret = devm_regmap_add_irq_chip(&pdev->dev, mfd_dev->regmap, irq,
+ IRQF_ONESHOT, 0,
+ &sun4i_gpadc_mfd_regmap_irq_chip,
+ &mfd_dev->regmap_irqc);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to add irq chip: %d\n", ret);
+ return ret;
+ }
+
+ mfd_cells = of_id->data;
+ ret = devm_mfd_add_devices(mfd_dev->dev, 0, mfd_cells, 2, NULL, 0,
+ NULL);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to add MFD devices: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+MODULE_DEVICE_TABLE(of, sun4i_gpadc_mfd_of_match);
+
+static struct platform_driver sun4i_gpadc_mfd_driver = {
+ .driver = {
+ .name = "sun4i-adc-mfd",
+ .of_match_table = of_match_ptr(sun4i_gpadc_mfd_of_match),
+ },
+ .probe = sun4i_gpadc_mfd_probe,
+};
+
+module_platform_driver(sun4i_gpadc_mfd_driver);
+
+MODULE_DESCRIPTION("Allwinner sunxi platforms' GPADC MFD core driver");
+MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/mfd/sun4i-gpadc-mfd.h b/include/linux/mfd/sun4i-gpadc-mfd.h
new file mode 100644
index 0000000..5cc7863
--- /dev/null
+++ b/include/linux/mfd/sun4i-gpadc-mfd.h
@@ -0,0 +1,94 @@
+/* Header of ADC MFD core driver for sunxi platforms
+ *
+ * Copyright (c) 2016 Quentin Schulz <quentin.schulz@free-electrons.mfd>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ */
+
+#ifndef __SUN4I_GPADC_MFD__H__
+#define __SUN4I_GPADC_MFD__H__
+
+#define SUN4I_GPADC_CTRL0 0x00
+
+#define SUN4I_GPADC_CTRL0_ADC_FIRST_DLY(x) ((GENMASK(7, 0) & (x)) << 24)
+#define SUN4I_GPADC_CTRL0_ADC_FIRST_DLY_MODE BIT(23)
+#define SUN4I_GPADC_CTRL0_ADC_CLK_SELECT BIT(22)
+#define SUN4I_GPADC_CTRL0_ADC_CLK_DIVIDER(x) ((GENMASK(1, 0) & (x)) << 20)
+#define SUN4I_GPADC_CTRL0_FS_DIV(x) ((GENMASK(3, 0) & (x)) << 16)
+#define SUN4I_GPADC_CTRL0_T_ACQ(x) (GENMASK(15, 0) & (x))
+
+#define SUN4I_GPADC_CTRL1 0x04
+
+#define SUN4I_GPADC_CTRL1_STYLUS_UP_DEBOUNCE(x) ((GENMASK(7, 0) & (x)) << 12)
+#define SUN4I_GPADC_CTRL1_STYLUS_UP_DEBOUNCE_EN BIT(9)
+#define SUN4I_GPADC_CTRL1_TOUCH_PAN_CALI_EN BIT(6)
+#define SUN4I_GPADC_CTRL1_TP_DUAL_EN BIT(5)
+#define SUN4I_GPADC_CTRL1_TP_MODE_EN BIT(4)
+#define SUN4I_GPADC_CTRL1_TP_ADC_SELECT BIT(3)
+#define SUN4I_GPADC_CTRL1_ADC_CHAN_SELECT(x) (GENMASK(2, 0) & (x))
+
+/* TP_CTRL1 bits for sun6i SOCs */
+#define SUN6I_GPADC_CTRL1_TOUCH_PAN_CALI_EN BIT(7)
+#define SUN6I_GPADC_CTRL1_TP_DUAL_EN BIT(6)
+#define SUN6I_GPADC_CTRL1_TP_MODE_EN BIT(5)
+#define SUN6I_GPADC_CTRL1_TP_ADC_SELECT BIT(4)
+#define SUN6I_GPADC_CTRL1_ADC_CHAN_SELECT(x) (GENMASK(3, 0) & BIT(x))
+
+#define SUN4I_GPADC_CTRL2 0x08
+
+#define SUN4I_GPADC_CTRL2_TP_SENSITIVE_ADJUST(x) ((GENMASK(3, 0) & (x)) << 28)
+#define SUN4I_GPADC_CTRL2_TP_MODE_SELECT(x) ((GENMASK(1, 0) & (x)) << 26)
+#define SUN4I_GPADC_CTRL2_PRE_MEA_EN BIT(24)
+#define SUN4I_GPADC_CTRL2_PRE_MEA_THRE_CNT(x) (GENMASK(23, 0) & (x))
+
+#define SUN4I_GPADC_CTRL3 0x0c
+
+#define SUN4I_GPADC_CTRL3_FILTER_EN BIT(2)
+#define SUN4I_GPADC_CTRL3_FILTER_TYPE(x) (GENMASK(1, 0) & (x))
+
+#define SUN4I_GPADC_TPR 0x18
+
+#define SUN4I_GPADC_TPR_TEMP_ENABLE BIT(16)
+#define SUN4I_GPADC_TPR_TEMP_PERIOD(x) (GENMASK(15, 0) & (x))
+
+#define SUN4I_GPADC_INT_FIFOC 0x10
+
+#define SUN4I_GPADC_INT_FIFOC_TEMP_IRQ_EN BIT(18)
+#define SUN4I_GPADC_INT_FIFOC_TP_OVERRUN_IRQ_EN BIT(17)
+#define SUN4I_GPADC_INT_FIFOC_TP_DATA_IRQ_EN BIT(16)
+#define SUN4I_GPADC_INT_FIFOC_TP_DATA_XY_CHANGE BIT(13)
+#define SUN4I_GPADC_INT_FIFOC_TP_FIFO_TRIG_LEVEL(x) ((GENMASK(4, 0) & (x)) << 8)
+#define SUN4I_GPADC_INT_FIFOC_TP_DATA_DRQ_EN BIT(7)
+#define SUN4I_GPADC_INT_FIFOC_TP_FIFO_FLUSH BIT(4)
+#define SUN4I_GPADC_INT_FIFOC_TP_UP_IRQ_EN BIT(1)
+#define SUN4I_GPADC_INT_FIFOC_TP_DOWN_IRQ_EN BIT(0)
+
+#define SUN4I_GPADC_INT_FIFOS 0x14
+
+#define SUN4I_GPADC_INT_FIFOS_TEMP_DATA_PENDING BIT(18)
+#define SUN4I_GPADC_INT_FIFOS_FIFO_OVERRUN_PENDING BIT(17)
+#define SUN4I_GPADC_INT_FIFOS_FIFO_DATA_PENDING BIT(16)
+#define SUN4I_GPADC_INT_FIFOS_TP_IDLE_FLG BIT(2)
+#define SUN4I_GPADC_INT_FIFOS_TP_UP_PENDING BIT(1)
+#define SUN4I_GPADC_INT_FIFOS_TP_DOWN_PENDING BIT(0)
+
+#define SUN4I_GPADC_CDAT 0x1c
+#define SUN4I_GPADC_TEMP_DATA 0x20
+#define SUN4I_GPADC_DATA 0x24
+
+#define SUN4I_GPADC_IRQ_FIFO_DATA 0
+#define SUN4I_GPADC_IRQ_TEMP_DATA 1
+
+/* 10s delay before suspending the IP */
+#define SUN4I_GPADC_AUTOSUSPEND_DELAY 10000
+
+struct sun4i_gpadc_mfd_dev {
+ struct device *dev;
+ struct regmap *regmap;
+ struct regmap_irq_chip_data *regmap_irqc;
+ void __iomem *regs;
+};
+
+#endif
--
2.5.0