* [PATCH v6 1/4] pwm: Imagination Technologies PWM DAC driver
2014-11-28 18:12 [PATCH v6 0/4] Initial support for ImgTec PWM DAC and PDM DAC Naidu Tellapati
@ 2014-11-28 18:12 ` Naidu Tellapati
2014-11-28 18:12 ` [PATCH v6 2/4] DT: pwm: Add binding document for IMG PWM DAC Naidu Tellapati
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Naidu Tellapati @ 2014-11-28 18:12 UTC (permalink / raw)
To: thierry.reding, abrestic, gregkh, arnd, James.Hartley,
Ezequiel.Garcia
Cc: devicetree, linux-pwm, Arul.Ramasamy, Sai.Masarapu,
Naidu Tellapati, Naidu Tellapati
The Pistachio SOC from Imagination Technologies includes a Pulse Width
Modulation DAC which produces 1 to 4 digital bit-outputs which represent
digital waveforms. These PWM outputs are primarily in charge of controlling
backlight LED devices.
Signed-off-by: Naidu Tellapati <Naidu.Tellapati@imgtec.com>
Signed-off-by: Sai Masarapu <Sai.Masarapu@imgtec.com>
---
drivers/pwm/Kconfig | 13 +++
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-img.c | 250 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 264 insertions(+), 0 deletions(-)
create mode 100644 drivers/pwm/pwm-img.c
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index ef2dd2e..21b82b9 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -110,6 +110,19 @@ config PWM_FSL_FTM
To compile this driver as a module, choose M here: the module
will be called pwm-fsl-ftm.
+config PWM_IMG
+ tristate "Imagination Technologies PWM driver"
+ depends on HAS_IOMEM
+ depends on MFD_SYSCON
+ depends on COMMON_CLK
+ depends on MIPS || COMPILE_TEST
+ help
+ Generic PWM framework driver for Imagination Technologies
+ PWM block which supports 4 channels.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-img
+
config PWM_IMX
tristate "i.MX PWM support"
depends on ARCH_MXC
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index c458606..29655fd 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o
obj-$(CONFIG_PWM_CLPS711X) += pwm-clps711x.o
obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o
obj-$(CONFIG_PWM_FSL_FTM) += pwm-fsl-ftm.o
+obj-$(CONFIG_PWM_IMG) += pwm-img.o
obj-$(CONFIG_PWM_IMX) += pwm-imx.o
obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o
obj-$(CONFIG_PWM_LP3943) += pwm-lp3943.o
diff --git a/drivers/pwm/pwm-img.c b/drivers/pwm/pwm-img.c
new file mode 100644
index 0000000..48204cb
--- /dev/null
+++ b/drivers/pwm/pwm-img.c
@@ -0,0 +1,250 @@
+/*
+ * Imagination Technologies Pulse Width Modulator driver
+ *
+ * Copyright (c) 2014, Imagination Technologies
+ *
+ * Based on drivers/pwm/pwm-tegra.c, Copyright (c) 2010, NVIDIA Corporation
+ *
+ * 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.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+/* PWM registers */
+#define PWM_CTRL_CFG 0x0000
+#define PWM_CTRL_CFG_NO_SUB_DIV 0
+#define PWM_CTRL_CFG_SUB_DIV0 1
+#define PWM_CTRL_CFG_SUB_DIV1 2
+#define PWM_CTRL_CFG_SUB_DIV0_DIV1 3
+#define PWM_CTRL_CFG_DIV_SHIFT(ch) ((ch) * 2 + 4)
+#define PWM_CTRL_CFG_DIV_MASK 0x3
+
+#define PWM_CH_CFG(ch) (0x4 + (ch) * 4)
+#define PWM_CH_CFG_TMBASE_SHIFT 0
+#define PWM_CH_CFG_DUTY_SHIFT 16
+
+#define PERIP_PWM_PDM_CONTROL 0x0140
+#define PERIP_PWM_PDM_CONTROL_CH_MASK 0x1
+#define PERIP_PWM_PDM_CONTROL_CH_SHIFT(ch) ((ch) * 4)
+
+#define MAX_TMBASE_STEPS 65536
+
+struct img_pwm_chip {
+ struct device *dev;
+ struct pwm_chip chip;
+ struct clk *pwm_clk;
+ struct clk *sys_clk;
+ void __iomem *base;
+ struct regmap *periph_regs;
+};
+
+static inline struct img_pwm_chip *to_img_pwm_chip(struct pwm_chip *chip)
+{
+ return container_of(chip, struct img_pwm_chip, chip);
+}
+
+static inline void img_pwm_writel(struct img_pwm_chip *chip,
+ u32 reg, u32 val)
+{
+ writel(val, chip->base + reg);
+}
+
+static inline u32 img_pwm_readl(struct img_pwm_chip *chip,
+ u32 reg)
+{
+ return readl(chip->base + reg);
+}
+
+static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns)
+{
+ u32 val, div, duty, timebase;
+ unsigned long mul, output_clk_hz, input_clk_hz;
+ struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip);
+
+ input_clk_hz = clk_get_rate(pwm_chip->pwm_clk);
+ output_clk_hz = DIV_ROUND_UP(NSEC_PER_SEC, period_ns);
+
+ mul = DIV_ROUND_UP(input_clk_hz, output_clk_hz);
+ if (mul <= MAX_TMBASE_STEPS) {
+ div = PWM_CTRL_CFG_NO_SUB_DIV;
+ timebase = DIV_ROUND_UP(mul, 1);
+ } else if (mul <= MAX_TMBASE_STEPS * 8) {
+ div = PWM_CTRL_CFG_SUB_DIV0;
+ timebase = DIV_ROUND_UP(mul, 8);
+ } else if (mul <= MAX_TMBASE_STEPS * 64) {
+ div = PWM_CTRL_CFG_SUB_DIV1;
+ timebase = DIV_ROUND_UP(mul, 64);
+ } else if (mul <= MAX_TMBASE_STEPS * 512) {
+ div = PWM_CTRL_CFG_SUB_DIV0_DIV1;
+ timebase = DIV_ROUND_UP(mul, 512);
+ } else if (mul > MAX_TMBASE_STEPS * 512) {
+ dev_err(chip->dev,
+ "failed to configure timebase steps/divider value.\n");
+ return -EINVAL;
+ }
+
+ duty = DIV_ROUND_UP(timebase * duty_ns, period_ns);
+
+ val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
+ val &= ~(PWM_CTRL_CFG_DIV_MASK << PWM_CTRL_CFG_DIV_SHIFT(pwm->hwpwm));
+ val |= (div & PWM_CTRL_CFG_DIV_MASK) <<
+ PWM_CTRL_CFG_DIV_SHIFT(pwm->hwpwm);
+ img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
+
+ val = (duty << PWM_CH_CFG_DUTY_SHIFT) |
+ (timebase << PWM_CH_CFG_TMBASE_SHIFT);
+ img_pwm_writel(pwm_chip, PWM_CH_CFG(pwm->hwpwm), val);
+
+ return 0;
+}
+
+static int img_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ u32 val;
+ struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip);
+
+ val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
+ val |= BIT(pwm->hwpwm);
+ img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
+
+ regmap_update_bits(pwm_chip->periph_regs, PERIP_PWM_PDM_CONTROL,
+ PERIP_PWM_PDM_CONTROL_CH_MASK <<
+ PERIP_PWM_PDM_CONTROL_CH_SHIFT(pwm->hwpwm), 0);
+
+ return 0;
+}
+
+static void img_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ u32 val;
+ struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip);
+
+ val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
+ val &= ~BIT(pwm->hwpwm);
+ img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
+}
+
+static const struct pwm_ops img_pwm_ops = {
+ .config = img_pwm_config,
+ .enable = img_pwm_enable,
+ .disable = img_pwm_disable,
+ .owner = THIS_MODULE,
+};
+
+static int img_pwm_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct resource *res;
+ struct img_pwm_chip *pwm;
+
+ pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
+ if (!pwm)
+ return -ENOMEM;
+
+ pwm->dev = &pdev->dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pwm->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(pwm->base))
+ return PTR_ERR(pwm->base);
+
+ pwm->periph_regs = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
+ "img,cr-periph");
+ if (IS_ERR(pwm->periph_regs))
+ return PTR_ERR(pwm->periph_regs);
+
+ pwm->sys_clk = devm_clk_get(&pdev->dev, "sys");
+ if (IS_ERR(pwm->sys_clk)) {
+ dev_err(&pdev->dev, "failed to get system clock.\n");
+ return PTR_ERR(pwm->sys_clk);
+ }
+
+ pwm->pwm_clk = devm_clk_get(&pdev->dev, "pwm");
+ if (IS_ERR(pwm->pwm_clk)) {
+ dev_err(&pdev->dev, "failed to get pwm clock.\n");
+ return PTR_ERR(pwm->pwm_clk);
+ }
+
+ ret = clk_prepare_enable(pwm->sys_clk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "could not prepare or enable sys clock.\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(pwm->pwm_clk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "could not prepare or enable pwm clock.\n");
+ goto disable_sysclk;
+ }
+
+ pwm->chip.dev = &pdev->dev;
+ pwm->chip.ops = &img_pwm_ops;
+ pwm->chip.base = -1;
+ pwm->chip.npwm = 4;
+
+ ret = pwmchip_add(&pwm->chip);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "pwmchip_add failed: %d\n", ret);
+ goto disable_pwmclk;
+ }
+
+ platform_set_drvdata(pdev, pwm);
+
+disable_pwmclk:
+ clk_disable_unprepare(pwm->pwm_clk);
+disable_sysclk:
+ clk_disable_unprepare(pwm->sys_clk);
+
+ return 0;
+}
+
+static int img_pwm_remove(struct platform_device *pdev)
+{
+ struct img_pwm_chip *pwm_chip = platform_get_drvdata(pdev);
+ u32 val;
+ unsigned int i;
+
+ for (i = 0; i < pwm_chip->chip.npwm; i++) {
+ val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG);
+ val &= ~BIT(i);
+ img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val);
+ }
+
+ clk_disable_unprepare(pwm_chip->pwm_clk);
+ clk_disable_unprepare(pwm_chip->sys_clk);
+
+ return pwmchip_remove(&pwm_chip->chip);
+}
+
+static const struct of_device_id img_pwm_of_match[] = {
+ { .compatible = "img,pistachio-pwm", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, img_pwm_of_match);
+
+static struct platform_driver img_pwm_driver = {
+ .driver = {
+ .name = "img-pwm",
+ .of_match_table = of_match_ptr(img_pwm_of_match),
+ },
+ .probe = img_pwm_probe,
+ .remove = img_pwm_remove,
+};
+module_platform_driver(img_pwm_driver);
+
+MODULE_AUTHOR("Sai Masarapu <Sai.Masarapu@imgtec.com>");
+MODULE_DESCRIPTION("Imagination Technologies PWM DAC driver");
+MODULE_LICENSE("GPL v2");
--
1.7.0.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v6 3/4] pdm: Imagination Technologies PDM DAC driver
2014-11-28 18:12 [PATCH v6 0/4] Initial support for ImgTec PWM DAC and PDM DAC Naidu Tellapati
2014-11-28 18:12 ` [PATCH v6 1/4] pwm: Imagination Technologies PWM DAC driver Naidu Tellapati
2014-11-28 18:12 ` [PATCH v6 2/4] DT: pwm: Add binding document for IMG PWM DAC Naidu Tellapati
@ 2014-11-28 18:12 ` Naidu Tellapati
2014-11-28 18:12 ` [PATCH v6 4/4] DT: pdm: Add binding document for IMG PDM DAC Naidu Tellapati
2014-12-05 11:52 ` [PATCH v6 0/4] Initial support for ImgTec PWM DAC and " Ezequiel Garcia
4 siblings, 0 replies; 6+ messages in thread
From: Naidu Tellapati @ 2014-11-28 18:12 UTC (permalink / raw)
To: thierry.reding, abrestic, gregkh, arnd, James.Hartley,
Ezequiel.Garcia
Cc: devicetree, linux-pwm, Arul.Ramasamy, Sai.Masarapu,
Naidu Tellapati, Naidu Tellapati
The Pistachio SOC from Imagination Technologies includes a Pulse Density
Modulation DAC which produces a form of analogue output according to the
relative density of output pulses to the intended analogue signal amplitude.
Four PDM outputs are provided that can be used to control targets such as LCD
backlight.
Signed-off-by: Naidu Tellapati <Naidu.Tellapati@imgtec.com>
Signed-off-by: Arul Ramasamy <Arul.Ramasamy@imgtec.com>
---
drivers/misc/Kconfig | 13 +
drivers/misc/Makefile | 1 +
drivers/misc/img-pdm.c | 672 +++++++++++++++++++++++++++++++++++++++++++++++
include/linux/img_pdm.h | 35 +++
4 files changed, 721 insertions(+), 0 deletions(-)
create mode 100644 drivers/misc/img-pdm.c
create mode 100644 include/linux/img_pdm.h
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index bbeb451..e2b9fa4 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -515,6 +515,19 @@ config VEXPRESS_SYSCFG
bus. System Configuration interface is one of the possible means
of generating transactions on this bus.
+config IMG_PDM
+ tristate "Imagination Technologies PDM driver"
+ depends on HAS_IOMEM
+ depends on MFD_SYSCON
+ depends on COMMON_CLK
+ depends on MIPS || COMPILE_TEST
+ help
+ PDM driver for Imagination Technologies PDM block which supports 4
+ channels.
+
+ To compile this driver as a module, choose M here: the module will
+ be called img-pdm.
+
source "drivers/misc/c2port/Kconfig"
source "drivers/misc/eeprom/Kconfig"
source "drivers/misc/cb710/Kconfig"
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 7d5c4cd..9b00a75 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -56,3 +56,4 @@ obj-$(CONFIG_GENWQE) += genwqe/
obj-$(CONFIG_ECHO) += echo/
obj-$(CONFIG_VEXPRESS_SYSCFG) += vexpress-syscfg.o
obj-$(CONFIG_CXL_BASE) += cxl/
+obj-$(CONFIG_IMG) += img-pdm.o
diff --git a/drivers/misc/img-pdm.c b/drivers/misc/img-pdm.c
new file mode 100644
index 0000000..9818a74
--- /dev/null
+++ b/drivers/misc/img-pdm.c
@@ -0,0 +1,672 @@
+/**
+ * Imagination Technologies Pulse Density Modulator driver
+ *
+ * Copyright (C) 2014 Imagination Technologies Ltd.
+ *
+ * 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/capability.h>
+#include <linux/clk.h>
+#include <linux/ctype.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/img_pdm.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/kobject.h>
+#include <linux/list.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+
+/* Registers */
+#define PERIP_PWM_PDM_CONTROL 0x0140
+#define PERIP_PWM_PDM_CONTROL_CH_MASK 0x1
+#define PERIP_PWM_PDM_CONTROL_CH_SHIFT(ch) ((ch) * 4)
+#define PERIP_PDM_CHANNEL_ENABLE 1
+#define PERIP_PDM_CHANNEL_DISABLE 0
+
+#define PERIP_PDM0_VAL 0x0144
+#define PERIP_PDM_CH_ADDR_SHIFT(ch) ((ch) * 4)
+#define PERIP_PDM_SRC_DATA_MASK 0xfff
+
+#define IMG_NUM_PDM 4
+#define PDM_CHANNEL_REQUESTED 1
+#define PDM_CHANNEL_ENABLED 2
+
+struct img_pdm_channel *pdm_channels;
+
+static DEFINE_MUTEX(pdm_lock);
+
+static struct img_pdm_channel *img_pdm_channel_request(unsigned int pdm_id);
+static int img_pdm_channel_free(struct img_pdm_channel *chan);
+
+static struct img_pdm_channel *of_img_pdm_channel_get(struct device_node *np)
+{
+ int err, index;
+ struct of_phandle_args args;
+ struct img_pdm_channel *chan;
+
+ err = of_parse_phandle_with_args(np, "pdms", "#pdm-cells",
+ index, &args);
+ if (err) {
+ pr_debug("%s(): can't parse \"pdms\" property\n", __func__);
+ return ERR_PTR(err);
+ }
+
+ if (args.args_count != 2) {
+ pr_debug("%s(): wrong #pwm-cells\n", __func__);
+ return ERR_PTR(-EINVAL);
+ }
+
+ chan = img_pdm_channel_request(args.args[0]);
+ if (chan)
+ img_pdm_channel_pulse_in_set(chan, args.args[1]);
+
+ return chan;
+}
+
+static void of_img_pdm_channel_put(struct device_node *np)
+{
+ int err, index;
+ struct of_phandle_args args;
+ struct img_pdm_channel *chan;
+
+ err = of_parse_phandle_with_args(np, "pdms", "#pdm-cells",
+ index, &args);
+ if (err) {
+ pr_debug("%s(): can't parse \"pdms\" property\n", __func__);
+ return;
+ }
+
+ if (args.args_count != 2) {
+ pr_debug("%s(): wrong #pwm-cells\n", __func__);
+ return;
+ }
+
+ if (args.args[0] < 0 || args.args[0] >= IMG_NUM_PDM || !pdm_channels)
+ return;
+
+ chan = &pdm_channels[args.args[0]];
+ img_pdm_channel_free(chan);
+}
+
+struct img_pdm_channel *img_pdm_channel_get(struct device *dev)
+{
+ /* look up via DT */
+ if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
+ return of_img_pdm_channel_get(dev->of_node);
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(img_pdm_channel_get);
+
+void img_pdm_channel_put(struct device *dev)
+{
+ /* look up via DT */
+ if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
+ of_img_pdm_channel_put(dev->of_node);
+}
+EXPORT_SYMBOL_GPL(img_pdm_channel_put);
+
+static struct img_pdm_channel *img_pdm_channel_request(unsigned int pdm_id)
+{
+ unsigned int i;
+ struct img_pdm_device *pdm_dev;
+ struct img_pdm_channel *chan;
+
+ mutex_lock(&pdm_lock);
+
+ if (pdm_id < 0 || pdm_id >= IMG_NUM_PDM || !pdm_channels)
+ return NULL;
+
+ pdm_dev = pdm_channels[0].pdm_dev;
+ if (!pdm_dev)
+ return NULL;
+
+ for (i = 0; i < IMG_NUM_PDM; i++) {
+ if (&pdm_channels[i] && (pdm_channels[i].pdm_id == pdm_id)) {
+ chan = &pdm_channels[i];
+ break;
+ }
+ }
+
+ if (!chan) {
+ mutex_unlock(&pdm_lock);
+ return NULL;
+ }
+
+ /* Check if channel is already requested */
+ if (test_bit(PDM_CHANNEL_REQUESTED, &chan->flags)) {
+ dev_err(&pdm_dev->pdev->dev,
+ "pdm channel %d already requested\n", chan->pdm_id);
+ mutex_unlock(&pdm_lock);
+ return NULL;
+ }
+
+ set_bit(PDM_CHANNEL_REQUESTED, &chan->flags);
+ mutex_unlock(&pdm_lock);
+
+ return chan;
+}
+
+static int img_pdm_channel_free(struct img_pdm_channel *chan)
+{
+ unsigned int i;
+ struct img_pdm_device *pdm_dev;
+
+ mutex_lock(&pdm_lock);
+
+ if (!pdm_channels || !chan) {
+ mutex_unlock(&pdm_lock);
+ return -EINVAL;
+ }
+
+ pdm_dev = pdm_channels[0].pdm_dev;
+ if (!pdm_dev) {
+ mutex_unlock(&pdm_lock);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < IMG_NUM_PDM; i++) {
+ if (&pdm_channels[i] && (&pdm_channels[i] == chan))
+ break;
+ }
+
+ if (i == IMG_NUM_PDM) {
+ dev_err(&pdm_dev->pdev->dev,
+ "Invalid pdm channel address to free\n");
+ mutex_unlock(&pdm_lock);
+ return -EINVAL;
+ }
+
+ if (test_bit(PDM_CHANNEL_ENABLED, &chan->flags)) {
+ dev_err(&pdm_dev->pdev->dev,
+ "can't free the channel while it is enabled\n");
+ mutex_unlock(&pdm_lock);
+ return -EINVAL;
+ }
+
+ if (!test_bit(PDM_CHANNEL_REQUESTED, &chan->flags)) {
+ dev_err(&pdm_dev->pdev->dev,
+ "trying to free channel which is not requested\n");
+ mutex_unlock(&pdm_lock);
+ return -EINVAL;
+ }
+
+ clear_bit(PDM_CHANNEL_REQUESTED, &chan->flags);
+
+ mutex_unlock(&pdm_lock);
+
+ return 0;
+}
+
+int img_pdm_channel_enable_get(struct img_pdm_channel *chan)
+{
+ int ret;
+ struct img_pdm_device *pdm_dev;
+
+ if (!chan)
+ return -EINVAL;
+
+ pdm_dev = chan->pdm_dev;
+
+ if (!test_bit(PDM_CHANNEL_REQUESTED, &chan->flags)) {
+ dev_err(&pdm_dev->pdev->dev, "pdm chan is notrequested\n");
+ return -EINVAL;
+ }
+
+ if (test_bit(PDM_CHANNEL_ENABLED, &chan->flags))
+ ret = PERIP_PDM_CHANNEL_ENABLE;
+ else
+ ret = PERIP_PDM_CHANNEL_DISABLE;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(img_pdm_channel_enable_get);
+
+int img_pdm_channel_pulse_in_get(struct img_pdm_channel *chan)
+{
+ u32 val;
+ struct img_pdm_device *pdm_dev;
+
+ if (!chan)
+ return -EINVAL;
+
+ pdm_dev = chan->pdm_dev;
+
+ if (!test_bit(PDM_CHANNEL_REQUESTED, &chan->flags)) {
+ dev_err(&pdm_dev->pdev->dev, "pdm chan is notrequested\n");
+ return -EINVAL;
+ }
+
+ regmap_read(pdm_dev->periph_regs,
+ PERIP_PDM0_VAL +
+ PERIP_PDM_CH_ADDR_SHIFT(chan->pdm_id), &val);
+ val &= PERIP_PDM_SRC_DATA_MASK;
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(img_pdm_channel_pulse_in_get);
+
+int img_pdm_channel_enable_set(struct img_pdm_channel *chan, bool state)
+{
+ struct img_pdm_device *pdm_dev;
+
+ if (!chan)
+ return -EINVAL;
+
+ pdm_dev = chan->pdm_dev;
+
+ if (!test_bit(PDM_CHANNEL_REQUESTED, &chan->flags)) {
+ dev_err(&pdm_dev->pdev->dev, "invalid pdm chan enable\n");
+ return -EINVAL;
+ }
+
+ if ((state == PERIP_PDM_CHANNEL_ENABLE) &&
+ test_bit(PDM_CHANNEL_ENABLED, &chan->flags)) {
+ dev_err(&pdm_dev->pdev->dev, "pdm chan already enabled\n");
+ return -EBUSY;
+ } else if ((state == PERIP_PDM_CHANNEL_DISABLE) &&
+ !test_bit(PDM_CHANNEL_ENABLED, &chan->flags)) {
+ dev_err(&pdm_dev->pdev->dev, "pdm chan not enabled\n");
+ return -EINVAL;
+ }
+
+ if (state == PERIP_PDM_CHANNEL_ENABLE) {
+ regmap_update_bits(pdm_dev->periph_regs,
+ PERIP_PWM_PDM_CONTROL,
+ PERIP_PWM_PDM_CONTROL_CH_MASK <<
+ PERIP_PWM_PDM_CONTROL_CH_SHIFT(chan->pdm_id),
+ 1);
+ set_bit(PDM_CHANNEL_ENABLED, &chan->flags);
+ } else if (state == PERIP_PDM_CHANNEL_DISABLE) {
+ regmap_write(pdm_dev->periph_regs,
+ PERIP_PDM0_VAL +
+ PERIP_PDM_CH_ADDR_SHIFT(chan->pdm_id), 0);
+ regmap_update_bits(pdm_dev->periph_regs,
+ PERIP_PWM_PDM_CONTROL,
+ PERIP_PWM_PDM_CONTROL_CH_MASK <<
+ PERIP_PWM_PDM_CONTROL_CH_SHIFT(chan->pdm_id),
+ 0);
+ clear_bit(PDM_CHANNEL_ENABLED, &chan->flags);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(img_pdm_channel_enable_set);
+
+int img_pdm_channel_pulse_in_set(struct img_pdm_channel *chan, u32 val)
+{
+ struct img_pdm_device *pdm_dev;
+
+ if (!chan)
+ return -EINVAL;
+
+ pdm_dev = chan->pdm_dev;
+
+ if (!test_bit(PDM_CHANNEL_REQUESTED, &chan->flags)) {
+ dev_err(&pdm_dev->pdev->dev, "invalid pdm chan to configure\n");
+ return -EINVAL;
+ }
+
+ val = val & PERIP_PDM_SRC_DATA_MASK;
+ regmap_write(pdm_dev->periph_regs,
+ PERIP_PDM0_VAL +
+ PERIP_PDM_CH_ADDR_SHIFT(chan->pdm_id), val);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(img_pdm_channel_pulse_in_set);
+
+static ssize_t img_pdm_enable_read(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ int ret;
+ unsigned int ch_num, val;
+ unsigned char kobj_name[2];
+ struct platform_device *pdev;
+ struct img_pdm_device *pdm_dev;
+
+ pdev = to_platform_device(kobj_to_dev(kobj->parent));
+ pdm_dev = platform_get_drvdata(pdev);
+ kobj_name[0] = *(kobj->name+3);
+ kobj_name[1] = '\0';
+ ret = kstrtou32(kobj_name, 10, &ch_num);
+ if (ret) {
+ dev_err(&pdev->dev, "could not parse channel number string\n");
+ return ret;
+ }
+
+ val = img_pdm_channel_enable_get(&pdm_channels[ch_num]);
+
+ return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t img_pdm_pulse_in_read(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ int ret;
+ unsigned int ch_num, val;
+ unsigned char kobj_name[2];
+ struct platform_device *pdev;
+ struct img_pdm_device *pdm_dev;
+
+ pdev = to_platform_device(kobj_to_dev(kobj->parent));
+ pdm_dev = platform_get_drvdata(pdev);
+ kobj_name[0] = *(kobj->name+3);
+ kobj_name[1] = '\0';
+ ret = kstrtou32(kobj_name, 10, &ch_num);
+ if (ret) {
+ dev_err(&pdev->dev, "could not parse channel number string\n");
+ return ret;
+ }
+
+ val = img_pdm_channel_pulse_in_get(&pdm_channels[ch_num]);
+
+ return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t img_pdm_enable_write(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t size)
+{
+ int ret;
+ unsigned int ch_num, enable;
+ unsigned char kobj_name[2];
+ struct platform_device *pdev;
+ struct img_pdm_device *pdm_dev;
+
+ pdev = to_platform_device(kobj_to_dev(kobj->parent));
+ pdm_dev = platform_get_drvdata(pdev);
+ kobj_name[0] = *(kobj->name+3);
+ kobj_name[1] = '\0';
+ ret = kstrtou32(kobj_name, 10, &ch_num);
+ if (ret) {
+ dev_err(&pdev->dev, "could not parse channel number string\n");
+ return ret;
+ }
+
+ ret = kstrtou32(buf, 10, &enable);
+ if (ret) {
+ dev_err(&pdev->dev, "could not parse enable attr value\n");
+ return ret;
+ }
+
+ if (enable > PERIP_PDM_CHANNEL_ENABLE) {
+ dev_err(&pdev->dev, "invalid enable attribute value\n");
+ return ret;
+ }
+
+ ret = img_pdm_channel_enable_set(&pdm_channels[ch_num],
+ enable ? PERIP_PDM_CHANNEL_ENABLE :
+ PERIP_PDM_CHANNEL_DISABLE);
+ if (ret < 0)
+ return ret;
+
+ return size;
+}
+
+static ssize_t img_pdm_pulse_in_write(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t size)
+{
+ int ret;
+ unsigned int pulse_in, ch_num;
+ unsigned char kobj_name[2];
+ struct platform_device *pdev;
+ struct img_pdm_device *pdm_dev;
+
+ pdev = to_platform_device(kobj_to_dev(kobj->parent));
+ pdm_dev = platform_get_drvdata(pdev);
+ kobj_name[0] = *(kobj->name+3);
+ kobj_name[1] = '\0';
+ ret = kstrtou32(kobj_name, 10, &ch_num);
+ if (ret) {
+ dev_err(&pdev->dev, "could not parse channel number string\n");
+ return ret;
+ }
+
+ ret = kstrtouint(buf, 16, &pulse_in);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "could not parse pulse_in attr value\n");
+ return ret;
+ }
+
+ if (pulse_in > PERIP_PDM_SRC_DATA_MASK) {
+ dev_err(&pdev->dev,
+ "invalid attr value for pulse_in string\n");
+ return -EINVAL;
+ }
+
+ ret = img_pdm_channel_pulse_in_set(&pdm_channels[ch_num], pulse_in);
+ if (ret < 0)
+ return ret;
+
+ return size;
+}
+
+#define PDM_ATTR(_name, _mode, _show, _store) \
+struct kobj_attribute pdm_attr_##_name = { \
+ .attr = {.name = __stringify(_name), .mode = _mode}, \
+ .show = _show, \
+ .store = _store, \
+}
+
+static PDM_ATTR(enable, S_IRUGO | S_IWUSR, img_pdm_enable_read,
+ img_pdm_enable_write);
+static PDM_ATTR(pulse_in, S_IRUGO | S_IWUSR, img_pdm_pulse_in_read,
+ img_pdm_pulse_in_write);
+
+static struct attribute *pdm_sysfs_attrs[] = {
+ &pdm_attr_enable.attr,
+ &pdm_attr_pulse_in.attr,
+ NULL,
+};
+
+static const struct attribute_group pdm_attr_group = {
+ .attrs = pdm_sysfs_attrs,
+};
+
+static ssize_t img_pdm_export(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ int ret;
+ unsigned int ch_num;
+ unsigned char buf1[5];
+ struct platform_device *pdev;
+ struct img_pdm_device *pdm_dev;
+
+ pdev = to_platform_device(dev);
+ pdm_dev = platform_get_drvdata(pdev);
+
+ ret = kstrtou32(buf, 10, &ch_num);
+ if (ret) {
+ dev_err(&pdev->dev, "could not parse channel number string\n");
+ return ret;
+ }
+
+ if (img_pdm_channel_request(ch_num) == NULL)
+ return -EINVAL;
+
+ memset(buf1, 0, sizeof(buf1));
+ sprintf(buf1, "pdm%d", ch_num);
+ pdm_dev->pdm_kobj[ch_num] = kobject_create_and_add(buf1,
+ &pdev->dev.kobj);
+ if (!pdm_dev->pdm_kobj[ch_num])
+ return -ENOMEM;
+
+ ret = sysfs_create_group(pdm_dev->pdm_kobj[ch_num], &pdm_attr_group);
+ if (ret) {
+ kobject_put(pdm_dev->pdm_kobj[ch_num]);
+ dev_err(&pdev->dev, "unable to register device attributes\n");
+ return ret;
+ }
+
+ return size;
+}
+
+static ssize_t img_pdm_unexport(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ int ret;
+ unsigned int ch_num;
+ struct img_pdm_channel *channel;
+ struct platform_device *pdev;
+ struct img_pdm_device *pdm_dev;
+
+ pdev = to_platform_device(dev);
+ pdm_dev = platform_get_drvdata(pdev);
+
+ ret = kstrtou32(buf, 10, &ch_num);
+ if (ret < 0)
+ return ret;
+
+ if (ch_num < 0 || ch_num >= IMG_NUM_PDM) {
+ dev_err(&pdev->dev, "Invalid channel number %d\n", ch_num);
+ return -EINVAL;
+ }
+
+ channel = &pdm_channels[ch_num];
+ if (img_pdm_channel_free(channel) < 0)
+ return -EINVAL;
+
+ if (pdm_dev->pdm_kobj[ch_num]) {
+ sysfs_remove_group(pdm_dev->pdm_kobj[ch_num], &pdm_attr_group);
+ kobject_put(pdm_dev->pdm_kobj[ch_num]);
+ }
+
+ return size;
+}
+
+/* The sysfs attributes. */
+static DEVICE_ATTR(export, S_IRUGO | S_IWUSR, NULL, img_pdm_export);
+static DEVICE_ATTR(unexport, S_IRUGO | S_IWUSR, NULL, img_pdm_unexport);
+
+static struct attribute *img_pdm_sysfs_attrs[] = {
+ &dev_attr_export.attr,
+ &dev_attr_unexport.attr,
+ NULL,
+};
+
+static const struct attribute_group img_pdm_attr_group = {
+ .attrs = img_pdm_sysfs_attrs,
+};
+
+static int img_pdm_probe(struct platform_device *pdev)
+{
+ int ret;
+ unsigned int i;
+ struct img_pdm_device *pdm_dev;
+
+ pdm_dev = devm_kzalloc(&pdev->dev,
+ sizeof(struct img_pdm_device), GFP_KERNEL);
+ if (!pdm_dev)
+ return -ENOMEM;
+
+ pdm_dev->pdm_kobj = devm_kzalloc(&pdev->dev,
+ IMG_NUM_PDM *
+ sizeof(struct img_pdm_device *),
+ GFP_KERNEL);
+ if (!pdm_dev->pdm_kobj)
+ return -ENOMEM;
+
+ pdm_channels = devm_kzalloc(&pdev->dev,
+ IMG_NUM_PDM *
+ sizeof(struct img_pdm_channel), GFP_KERNEL);
+ if (!pdm_channels)
+ return -ENOMEM;
+
+ pdm_dev->periph_regs = syscon_regmap_lookup_by_phandle(
+ pdev->dev.of_node, "img,cr-periph");
+ if (IS_ERR(pdm_dev->periph_regs))
+ return PTR_ERR(pdm_dev->periph_regs);
+
+ pdm_dev->clk = devm_clk_get(&pdev->dev, "pdm");
+ if (IS_ERR(pdm_dev->clk)) {
+ dev_err(&pdev->dev, "failed to get pdm clock\n");
+ return PTR_ERR(pdm_dev->clk);
+ }
+
+ ret = clk_prepare_enable(pdm_dev->clk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "could not prepare or enable pdm clock.\n");
+ return ret;
+ }
+
+ for (i = 0; i < IMG_NUM_PDM; i++) {
+ pdm_channels[i].pdm_id = i;
+ pdm_channels[i].pdm_dev = pdm_dev;
+ }
+
+ ret = sysfs_create_group(&pdev->dev.kobj, &img_pdm_attr_group);
+ if (ret) {
+ dev_err(&pdev->dev, "unable to register device attributes\n");
+ clk_disable_unprepare(pdm_dev->clk);
+ return ret;
+ }
+
+ pdm_dev->pdev = pdev;
+ platform_set_drvdata(pdev, pdm_dev);
+
+ return 0;
+}
+
+static int img_pdm_remove(struct platform_device *pdev)
+{
+ unsigned int i;
+ struct img_pdm_channel *chan;
+ struct img_pdm_device *pdm_dev;
+
+ pdm_dev = platform_get_drvdata(pdev);
+
+ for (i = 0; i < IMG_NUM_PDM; i++) {
+ chan = &pdm_channels[i];
+ if (test_bit(PDM_CHANNEL_REQUESTED, &chan->flags)) {
+ img_pdm_channel_enable_set(chan,
+ PERIP_PDM_CHANNEL_DISABLE);
+ img_pdm_channel_pulse_in_set(chan, 0);
+ if (pdm_dev->pdm_kobj[i]) {
+ sysfs_remove_group(pdm_dev->pdm_kobj[i],
+ &pdm_attr_group);
+ kobject_del(pdm_dev->pdm_kobj[i]);
+ }
+ }
+ }
+
+ clk_disable_unprepare(pdm_dev->clk);
+
+ return 0;
+}
+
+static const struct of_device_id img_pdm_of_match[] = {
+ { .compatible = "img,pistachio-pdm", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, img_pdm_of_match);
+
+static struct platform_driver img_pdm_driver = {
+ .driver = {
+ .name = "imgtec-pdm",
+ .of_match_table = img_pdm_of_match,
+ },
+ .probe = img_pdm_probe,
+ .remove = img_pdm_remove,
+};
+module_platform_driver(img_pdm_driver);
+
+MODULE_AUTHOR("Arul Ramasamy <Arul.Ramasamy@imgtec.com>");
+MODULE_DESCRIPTION("Imagination Technologies PDM driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/img_pdm.h b/include/linux/img_pdm.h
new file mode 100644
index 0000000..0203951
--- /dev/null
+++ b/include/linux/img_pdm.h
@@ -0,0 +1,35 @@
+/**
+ * Imagination Technologies Pulse Density Modulator driver
+ *
+ * Copyright (C) 2014 Imagination Technologies Ltd.
+ *
+ * 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 __IMG_PDM_H
+#define __IMG_PDM_H
+
+struct img_pdm_device {
+ struct clk *clk;
+ struct kobject **pdm_kobj;
+ struct regmap *periph_regs;
+ struct platform_device *pdev;
+};
+
+struct img_pdm_channel {
+ unsigned int pdm_id;
+ unsigned long flags;
+ struct img_pdm_device *pdm_dev;
+};
+
+void img_pdm_channel_put(struct device *dev);
+struct img_pdm_channel *img_pdm_channel_get(struct device *dev);
+int img_pdm_channel_enable_set(struct img_pdm_channel *chan, bool state);
+int img_pdm_channel_enable_get(struct img_pdm_channel *chan);
+int img_pdm_channel_pulse_in_get(struct img_pdm_channel *chan);
+int img_pdm_channel_pulse_in_set(struct img_pdm_channel *chan,
+ unsigned int val);
+
+#endif /* ifndef _IMG_PDM_H */
--
1.7.0.4
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