[PATCH] Input: add regulator haptic driver

[PATCH] Input: add regulator haptic driver

[hyunhee.kim]

From: Hyunhee Kim <hyunhee.kim@samsung.com>
Date: Wed, 9 Oct 2013 16:21:36 +0900
Subject: [PATCH] Input: add regulator haptic driver

The regulator haptic driver function can be used to control motor by on/off
regulator.
User can control the haptic driver by using force feedback framework.

Signed-off-by: Hyunhee Kim <hyunhee.kim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 drivers/input/misc/Kconfig            |    6 ++
 drivers/input/misc/Makefile           |    1 +
 drivers/input/misc/regulator-haptic.c |  185
+++++++++++++++++++++++++++++++++
 3 files changed, 192 insertions(+)
 create mode 100644 drivers/input/misc/regulator-haptic.c

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index bb698e1..f391cd7 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -82,6 +82,12 @@ config INPUT_ARIZONA_HAPTICS
 	  To compile this driver as a module, choose M here: the
 	  module will be called arizona-haptics.
 
+config INPUT_REGULATOR_HAPTIC
+	tristate "regulator haptics support"
+	select INPUT_FF_MEMLESS
+	help
+	  Say Y to enable support for the haptics module for regulator.
+
 config INPUT_BMA150
 	tristate "BMA150/SMB380 acceleration sensor support"
 	depends on I2C
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index d7fc17f..106f0bc 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_INPUT_ADXL34X_I2C)		+=
adxl34x-i2c.o
 obj-$(CONFIG_INPUT_ADXL34X_SPI)		+= adxl34x-spi.o
 obj-$(CONFIG_INPUT_APANEL)		+= apanel.o
 obj-$(CONFIG_INPUT_ARIZONA_HAPTICS)	+= arizona-haptics.o
+obj-$(CONFIG_INPUT_REGULATOR_HAPTIC)	+= regulator-haptic.o
 obj-$(CONFIG_INPUT_ATI_REMOTE2)		+= ati_remote2.o
 obj-$(CONFIG_INPUT_ATLAS_BTNS)		+= atlas_btns.o
 obj-$(CONFIG_INPUT_BFIN_ROTARY)		+= bfin_rotary.o
diff --git a/drivers/input/misc/regulator-haptic.c
b/drivers/input/misc/regulator-haptic.c
new file mode 100644
index 0000000..29f57ea
--- /dev/null
+++ b/drivers/input/misc/regulator-haptic.c
@@ -0,0 +1,185 @@
+/*
+ * Regulator haptic driver
+ *
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ *
+ * Author: Hyunhee Kim <hyunhee.kim@samsung.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/module.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/regulator/driver.h>
+
+struct regulator_haptic {
+	struct device *dev;
+	struct input_dev *input_dev;
+	struct work_struct work;
+	bool enabled;
+	struct regulator *regulator;
+	struct mutex mutex;
+	int level;
+};
+
+static void regulator_haptic_enable(struct regulator_haptic *haptic, bool
enable)
+{
+	int ret;
+
+	mutex_lock(&haptic->mutex);
+	if (enable && !haptic->enabled) {
+		haptic->enabled = true;
+		ret = regulator_enable(haptic->regulator);
+		if (ret)
+			pr_err("haptic: %s failed to enable regulator\n",
+				__func__);
+	} else if (!enable && haptic->enabled) {
+		haptic->enabled = false;
+		ret = regulator_disable(haptic->regulator);
+		if (ret)
+			pr_err("haptic: %s failed to disable regulator\n",
+				__func__);
+	}
+	mutex_unlock(&haptic->mutex);
+}
+
+static void regulator_haptic_work(struct work_struct *work)
+{
+	struct regulator_haptic *haptic = container_of(work,
+						       struct
regulator_haptic,
+						       work);
+	if (haptic->level)
+		regulator_haptic_enable(haptic, true);
+	else
+		regulator_haptic_enable(haptic, false);
+
+}
+
+static int regulator_haptic_play(struct input_dev *input, void *data,
+				struct ff_effect *effect)
+{
+	struct regulator_haptic *haptic = input_get_drvdata(input);
+
+	haptic->level = effect->u.rumble.strong_magnitude;
+	if (!haptic->level)
+		haptic->level = effect->u.rumble.weak_magnitude;
+	schedule_work(&haptic->work);
+
+	return 0;
+}
+
+static void regulator_haptic_close(struct input_dev *input)
+{
+	struct regulator_haptic *haptic = input_get_drvdata(input);
+
+	cancel_work_sync(&haptic->work);
+	regulator_haptic_enable(haptic, false);
+}
+
+static int regulator_haptic_probe(struct platform_device *pdev)
+{
+	struct regulator_haptic *haptic;
+	struct input_dev *input_dev;
+	int error;
+
+	haptic = kzalloc(sizeof(*haptic), GFP_KERNEL);
+	if (!haptic) {
+		dev_err(&pdev->dev, "unable to allocate memory for
haptic\n");
+		return -ENOMEM;
+	}
+
+	input_dev = input_allocate_device();
+
+	if (!input_dev) {
+		dev_err(&pdev->dev, "unable to allocate memory\n");
+		error =  -ENOMEM;
+		goto err_kfree_mem;
+	}
+
+	INIT_WORK(&haptic->work, regulator_haptic_work);
+	mutex_init(&haptic->mutex);
+	haptic->input_dev = input_dev;
+	haptic->dev = &pdev->dev;
+	haptic->regulator = regulator_get(&pdev->dev, "haptic");
+
+	if (IS_ERR(haptic->regulator)) {
+		error = PTR_ERR(haptic->regulator);
+		dev_err(&pdev->dev, "unable to get regulator, err: %d\n",
+			error);
+		goto err_ifree_mem;
+	}
+
+	haptic->input_dev->name = "regulator:haptic";
+	haptic->input_dev->dev.parent = &pdev->dev;
+	haptic->input_dev->close = regulator_haptic_close;
+	haptic->enabled = false;
+	input_set_drvdata(haptic->input_dev, haptic);
+	input_set_capability(haptic->input_dev, EV_FF, FF_RUMBLE);
+
+	error = input_ff_create_memless(input_dev, NULL,
+				      regulator_haptic_play);
+	if (error) {
+		dev_err(&pdev->dev,
+			"input_ff_create_memless() failed: %d\n",
+			error);
+		goto err_put_regulator;
+	}
+
+	error = input_register_device(haptic->input_dev);
+	if (error) {
+		dev_err(&pdev->dev,
+			"couldn't register input device: %d\n",
+			error);
+		goto err_destroy_ff;
+	}
+
+	platform_set_drvdata(pdev, haptic);
+
+	return 0;
+
+err_destroy_ff:
+	input_ff_destroy(haptic->input_dev);
+err_put_regulator:
+	regulator_put(haptic->regulator);
+err_ifree_mem:
+	input_free_device(haptic->input_dev);
+err_kfree_mem:
+	kfree(haptic);
+
+	return error;
+}
+
+static int regulator_haptic_remove(struct platform_device *pdev)
+{
+	struct regulator_haptic *haptic = platform_get_drvdata(pdev);
+
+	input_unregister_device(haptic->input_dev);
+
+	return 0;
+}
+
+static struct of_device_id regulator_haptic_dt_match[] = {
+	{ .compatible = "linux,regulator-haptic" },
+	{},
+};
+
+static struct platform_driver regulator_haptic_driver = {
+	.driver		= {
+		.name	= "regulator-haptic",
+		.owner	= THIS_MODULE,
+		.of_match_table = regulator_haptic_dt_match,
+	},
+
+	.probe		= regulator_haptic_probe,
+	.remove		= regulator_haptic_remove,
+};
+module_platform_driver(regulator_haptic_driver);
+
+MODULE_ALIAS("platform:regulator-haptic");
+MODULE_DESCRIPTION("Regulator haptic driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Hyunhee Kim <hyunhee.kim@samsung.com>");
-- 
1.7.9.5

Re: [PATCH] Input: add regulator haptic driver

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 1607 bytes --]

On Fri, Oct 11, 2013 at 11:22:00AM +0900, hyunhee.kim wrote:

> +	if (enable && !haptic->enabled) {
> +		haptic->enabled = true;
> +		ret = regulator_enable(haptic->regulator);
> +		if (ret)
> +			pr_err("haptic: %s failed to enable regulator\n",
> +				__func__);

These should probably set the flag after the regulator API call has
succeeded, otherwise if the call fails the driver will incorrectly
remember that the regulator is enabled and never disable it (or vice
versa on disable). 

> +static void regulator_haptic_work(struct work_struct *work)
> +{
> +	struct regulator_haptic *haptic = container_of(work,
> +						       struct
> regulator_haptic,
> +						       work);
> +	if (haptic->level)
> +		regulator_haptic_enable(haptic, true);
> +	else
> +		regulator_haptic_enable(haptic, false);
> +
> +}

Should the mutex for the level be at this level rather than in the
subfunctions?  Though it'd probably be just as well to inline the true
and false cases since there's basically two equivalent forks in the
enable function anyway.

> +
> +	haptic = kzalloc(sizeof(*haptic), GFP_KERNEL);
> +	if (!haptic) {
> +		dev_err(&pdev->dev, "unable to allocate memory for
> haptic\n");
> +		return -ENOMEM;
> +	}

Might be better to use devm_ functions throughout here, saves error
handling and cleanup code...

> +static int regulator_haptic_remove(struct platform_device *pdev)
> +{
> +	struct regulator_haptic *haptic = platform_get_drvdata(pdev);
> +
> +	input_unregister_device(haptic->input_dev);
> +
> +	return 0;

...which is currently missing.

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[PATCH v4] Input: add regulator haptic driver

[Hyunhee Kim]

From: Hyunhee Kim <hyunhee.kim@samsung.com>
Date: Wed, 9 Oct 2013 16:21:36 +0900
Subject: [PATCH] Input: add regulator haptic driver

Signed-off-by: Hyunhee Kim <hyunhee.kim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Aristeu Rozanski <aris@ruivo.org>

---
 drivers/input/misc/Kconfig            |   10 ++
 drivers/input/misc/Makefile           |    1 +
 drivers/input/misc/regulator-haptic.c |  187
+++++++++++++++++++++++++++++++++
 3 files changed, 198 insertions(+)
 create mode 100644 drivers/input/misc/regulator-haptic.c

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index bb698e1..21b4d5b 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -82,6 +82,16 @@ config INPUT_ARIZONA_HAPTICS
 	  To compile this driver as a module, choose M here: the
 	  module will be called arizona-haptics.
 
+config INPUT_REGULATOR_HAPTIC
+	tristate "support haptics on/off using regulator"
+	select INPUT_FF_MEMLESS
+	help
+	  Say Y to enable support for the haptic module. Haptic can be
+	  enabled/disabled by regulator.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called regulator-haptic.
+
 config INPUT_BMA150
 	tristate "BMA150/SMB380 acceleration sensor support"
 	depends on I2C
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index d7fc17f..106f0bc 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_INPUT_ADXL34X_I2C)		+=
adxl34x-i2c.o
 obj-$(CONFIG_INPUT_ADXL34X_SPI)		+= adxl34x-spi.o
 obj-$(CONFIG_INPUT_APANEL)		+= apanel.o
 obj-$(CONFIG_INPUT_ARIZONA_HAPTICS)	+= arizona-haptics.o
+obj-$(CONFIG_INPUT_REGULATOR_HAPTIC)	+= regulator-haptic.o
 obj-$(CONFIG_INPUT_ATI_REMOTE2)		+= ati_remote2.o
 obj-$(CONFIG_INPUT_ATLAS_BTNS)		+= atlas_btns.o
 obj-$(CONFIG_INPUT_BFIN_ROTARY)		+= bfin_rotary.o
diff --git a/drivers/input/misc/regulator-haptic.c
b/drivers/input/misc/regulator-haptic.c
new file mode 100644
index 0000000..bab2ad9
--- /dev/null
+++ b/drivers/input/misc/regulator-haptic.c
@@ -0,0 +1,187 @@
+/*
+ * Regulator haptic driver
+ *
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ *
+ * Author: Hyunhee Kim <hyunhee.kim@samsung.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/module.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/regulator/driver.h>
+
+struct regulator_haptic {
+	struct device *dev;
+	struct input_dev *input_dev;
+	struct work_struct work;
+	bool enabled;
+	struct regulator *regulator;
+	struct mutex mutex;
+	int level;
+};
+
+static void regulator_haptic_enable(struct regulator_haptic *haptic)
+{
+	int ret;
+
+	if (!haptic->enabled) {
+		ret = regulator_enable(haptic->regulator);
+		if (ret)
+			dev_err(haptic->dev, "failed to enable
regulator\n");
+		haptic->enabled = true;
+	}
+}
+
+static void regulator_haptic_disable(struct regulator_haptic *haptic)
+{
+	int ret;
+
+	if (haptic->enabled) {
+		ret = regulator_disable(haptic->regulator);
+		if (ret)
+			dev_err(haptic->dev, "failed to disable
regulator\n");
+		haptic->enabled = false;
+	}
+}
+
+static void regulator_haptic_work(struct work_struct *work)
+{
+	struct regulator_haptic *haptic = container_of(work,
+						       struct
regulator_haptic,
+						       work);
+	mutex_lock(&haptic->mutex);
+	if (haptic->level)
+		regulator_haptic_enable(haptic);
+	else
+		regulator_haptic_disable(haptic);
+	mutex_unlock(&haptic->mutex);
+}
+
+static int regulator_haptic_play(struct input_dev *input, void *data,
+				struct ff_effect *effect)
+{
+	struct regulator_haptic *haptic = input_get_drvdata(input);
+
+	haptic->level = effect->u.rumble.strong_magnitude;
+	if (!haptic->level)
+		haptic->level = effect->u.rumble.weak_magnitude;
+	schedule_work(&haptic->work);
+
+	return 0;
+}
+
+static void regulator_haptic_close(struct input_dev *input)
+{
+	struct regulator_haptic *haptic = input_get_drvdata(input);
+
+	cancel_work_sync(&haptic->work);
+	regulator_haptic_disable(haptic);
+}
+
+static int regulator_haptic_probe(struct platform_device *pdev)
+{
+	struct regulator_haptic *haptic;
+	struct input_dev *input_dev;
+	int error;
+
+	haptic = devm_kzalloc(&pdev->dev, sizeof(*haptic), GFP_KERNEL);
+	if (!haptic) {
+		dev_err(&pdev->dev, "unable to allocate memory for
haptic\n");
+		return -ENOMEM;
+	}
+
+	input_dev = input_allocate_device();
+
+	if (!input_dev) {
+		dev_err(&pdev->dev, "unable to allocate memory\n");
+		return  -ENOMEM;
+	}
+
+	INIT_WORK(&haptic->work, regulator_haptic_work);
+	mutex_init(&haptic->mutex);
+	haptic->input_dev = input_dev;
+	haptic->dev = &pdev->dev;
+	haptic->regulator = regulator_get(&pdev->dev, "haptic");
+
+	if (IS_ERR(haptic->regulator)) {
+		error = PTR_ERR(haptic->regulator);
+		dev_err(&pdev->dev, "unable to get regulator, err: %d\n",
+			error);
+		goto err_ifree_mem;
+	}
+
+	haptic->input_dev->name = "regulator:haptic";
+	haptic->input_dev->dev.parent = &pdev->dev;
+	haptic->input_dev->close = regulator_haptic_close;
+	haptic->enabled = false;
+	input_set_drvdata(haptic->input_dev, haptic);
+	input_set_capability(haptic->input_dev, EV_FF, FF_RUMBLE);
+
+	error = input_ff_create_memless(input_dev, NULL,
+				      regulator_haptic_play);
+	if (error) {
+		dev_err(&pdev->dev,
+			"input_ff_create_memless() failed: %d\n",
+			error);
+		goto err_put_regulator;
+	}
+
+	error = input_register_device(haptic->input_dev);
+	if (error) {
+		dev_err(&pdev->dev,
+			"couldn't register input device: %d\n",
+			error);
+		goto err_destroy_ff;
+	}
+
+	platform_set_drvdata(pdev, haptic);
+
+	return 0;
+
+err_destroy_ff:
+	input_ff_destroy(haptic->input_dev);
+err_put_regulator:
+	regulator_put(haptic->regulator);
+err_ifree_mem:
+	input_free_device(haptic->input_dev);
+
+	return error;
+}
+
+static int regulator_haptic_remove(struct platform_device *pdev)
+{
+	struct regulator_haptic *haptic = platform_get_drvdata(pdev);
+
+	input_unregister_device(haptic->input_dev);
+	regulator_put(haptic->regulator);
+
+	return 0;
+}
+
+static struct of_device_id regulator_haptic_dt_match[] = {
+	{ .compatible = "linux,regulator-haptic" },
+	{},
+};
+
+static struct platform_driver regulator_haptic_driver = {
+	.driver		= {
+		.name	= "regulator-haptic",
+		.owner	= THIS_MODULE,
+		.of_match_table = regulator_haptic_dt_match,
+	},
+
+	.probe		= regulator_haptic_probe,
+	.remove		= regulator_haptic_remove,
+};
+module_platform_driver(regulator_haptic_driver);
+
+MODULE_ALIAS("platform:regulator-haptic");
+MODULE_DESCRIPTION("Regulator haptic driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Hyunhee Kim <hyunhee.kim@samsung.com>");
-- 
1.7.9.5

Re: [PATCH v4] Input: add regulator haptic driver

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 492 bytes --]

On Fri, Oct 25, 2013 at 03:29:51PM +0900, Hyunhee Kim wrote:
> From: Hyunhee Kim <hyunhee.kim@samsung.com>
> Date: Wed, 9 Oct 2013 16:21:36 +0900
> Subject: [PATCH] Input: add regulator haptic driver

This is OK from a regulator point of view though there's still a lot of
use of regulator devm_ and input devm_ that could happen - it wasn't
just the kzalloc(), it was most of the allocations in the driver.

You also have some word wrapping in your e-mail so the patch probably
won't apply.

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[PATCH v5] Input: add regulator haptic driver

[Hyunhee Kim]

From: Hyunhee Kim <hyunhee.kim@samsung.com>
Date: Wed, 9 Oct 2013 16:21:36 +0900
Subject: [PATCH] Input: add regulator haptic driver

Signed-off-by: Hyunhee Kim <hyunhee.kim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Aristeu Rozanski <aris@ruivo.org>
---
 drivers/input/misc/Kconfig            |   10 ++
 drivers/input/misc/Makefile           |    1 +
 drivers/input/misc/regulator-haptic.c |  187 +++++++++++++++++++++++++++++++++
 3 files changed, 198 insertions(+)
 create mode 100644 drivers/input/misc/regulator-haptic.c

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index bb698e1..21b4d5b 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -82,6 +82,16 @@ config INPUT_ARIZONA_HAPTICS
 	  To compile this driver as a module, choose M here: the
 	  module will be called arizona-haptics.

+config INPUT_REGULATOR_HAPTIC
+	tristate "support haptics on/off using regulator"
+	select INPUT_FF_MEMLESS
+	help
+	  Say Y to enable support for the haptic module. Haptic can be
+	  enabled/disabled by regulator.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called regulator-haptic.
+
 config INPUT_BMA150
 	tristate "BMA150/SMB380 acceleration sensor support"
 	depends on I2C
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index d7fc17f..106f0bc 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_INPUT_ADXL34X_I2C)		+= adxl34x-i2c.o
 obj-$(CONFIG_INPUT_ADXL34X_SPI)		+= adxl34x-spi.o
 obj-$(CONFIG_INPUT_APANEL)		+= apanel.o
 obj-$(CONFIG_INPUT_ARIZONA_HAPTICS)	+= arizona-haptics.o
+obj-$(CONFIG_INPUT_REGULATOR_HAPTIC)	+= regulator-haptic.o
 obj-$(CONFIG_INPUT_ATI_REMOTE2)		+= ati_remote2.o
 obj-$(CONFIG_INPUT_ATLAS_BTNS)		+= atlas_btns.o
 obj-$(CONFIG_INPUT_BFIN_ROTARY)		+= bfin_rotary.o
diff --git a/drivers/input/misc/regulator-haptic.c b/drivers/input/misc/regulator-haptic.c
new file mode 100644
index 0000000..bab2ad9
--- /dev/null
+++ b/drivers/input/misc/regulator-haptic.c
@@ -0,0 +1,187 @@
+/*
+ * Regulator haptic driver
+ *
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ *
+ * Author: Hyunhee Kim <hyunhee.kim@samsung.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/module.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/regulator/driver.h>
+
+struct regulator_haptic {
+	struct device *dev;
+	struct input_dev *input_dev;
+	struct work_struct work;
+	bool enabled;
+	struct regulator *regulator;
+	struct mutex mutex;
+	int level;
+};
+
+static void regulator_haptic_enable(struct regulator_haptic *haptic)
+{
+	int ret;
+
+	if (!haptic->enabled) {
+		ret = regulator_enable(haptic->regulator);
+		if (ret)
+			dev_err(haptic->dev, "failed to enable regulator\n");
+		haptic->enabled = true;
+	}
+}
+
+static void regulator_haptic_disable(struct regulator_haptic *haptic)
+{
+	int ret;
+
+	if (haptic->enabled) {
+		ret = regulator_disable(haptic->regulator);
+		if (ret)
+			dev_err(haptic->dev, "failed to disable regulator\n");
+		haptic->enabled = false;
+	}
+}
+
+static void regulator_haptic_work(struct work_struct *work)
+{
+	struct regulator_haptic *haptic = container_of(work,
+						       struct regulator_haptic,
+						       work);
+	mutex_lock(&haptic->mutex);
+	if (haptic->level)
+		regulator_haptic_enable(haptic);
+	else
+		regulator_haptic_disable(haptic);
+	mutex_unlock(&haptic->mutex);
+}
+
+static int regulator_haptic_play(struct input_dev *input, void *data,
+				struct ff_effect *effect)
+{
+	struct regulator_haptic *haptic = input_get_drvdata(input);
+
+	haptic->level = effect->u.rumble.strong_magnitude;
+	if (!haptic->level)
+		haptic->level = effect->u.rumble.weak_magnitude;
+	schedule_work(&haptic->work);
+
+	return 0;
+}
+
+static void regulator_haptic_close(struct input_dev *input)
+{
+	struct regulator_haptic *haptic = input_get_drvdata(input);
+
+	cancel_work_sync(&haptic->work);
+	regulator_haptic_disable(haptic);
+}
+
+static int regulator_haptic_probe(struct platform_device *pdev)
+{
+	struct regulator_haptic *haptic;
+	struct input_dev *input_dev;
+	int error;
+
+	haptic = devm_kzalloc(&pdev->dev, sizeof(*haptic), GFP_KERNEL);
+	if (!haptic) {
+		dev_err(&pdev->dev, "unable to allocate memory for haptic\n");
+		return -ENOMEM;
+	}
+
+	input_dev = input_allocate_device();
+
+	if (!input_dev) {
+		dev_err(&pdev->dev, "unable to allocate memory\n");
+		return  -ENOMEM;
+	}
+
+	INIT_WORK(&haptic->work, regulator_haptic_work);
+	mutex_init(&haptic->mutex);
+	haptic->input_dev = input_dev;
+	haptic->dev = &pdev->dev;
+	haptic->regulator = regulator_get(&pdev->dev, "haptic");
+
+	if (IS_ERR(haptic->regulator)) {
+		error = PTR_ERR(haptic->regulator);
+		dev_err(&pdev->dev, "unable to get regulator, err: %d\n",
+			error);
+		goto err_ifree_mem;
+	}
+
+	haptic->input_dev->name = "regulator:haptic";
+	haptic->input_dev->dev.parent = &pdev->dev;
+	haptic->input_dev->close = regulator_haptic_close;
+	haptic->enabled = false;
+	input_set_drvdata(haptic->input_dev, haptic);
+	input_set_capability(haptic->input_dev, EV_FF, FF_RUMBLE);
+
+	error = input_ff_create_memless(input_dev, NULL,
+				      regulator_haptic_play);
+	if (error) {
+		dev_err(&pdev->dev,
+			"input_ff_create_memless() failed: %d\n",
+			error);
+		goto err_put_regulator;
+	}
+
+	error = input_register_device(haptic->input_dev);
+	if (error) {
+		dev_err(&pdev->dev,
+			"couldn't register input device: %d\n",
+			error);
+		goto err_destroy_ff;
+	}
+
+	platform_set_drvdata(pdev, haptic);
+
+	return 0;
+
+err_destroy_ff:
+	input_ff_destroy(haptic->input_dev);
+err_put_regulator:
+	regulator_put(haptic->regulator);
+err_ifree_mem:
+	input_free_device(haptic->input_dev);
+
+	return error;
+}
+
+static int regulator_haptic_remove(struct platform_device *pdev)
+{
+	struct regulator_haptic *haptic = platform_get_drvdata(pdev);
+
+	input_unregister_device(haptic->input_dev);
+	regulator_put(haptic->regulator);
+
+	return 0;
+}
+
+static struct of_device_id regulator_haptic_dt_match[] = {
+	{ .compatible = "linux,regulator-haptic" },
+	{},
+};
+
+static struct platform_driver regulator_haptic_driver = {
+	.driver		= {
+		.name	= "regulator-haptic",
+		.owner	= THIS_MODULE,
+		.of_match_table = regulator_haptic_dt_match,
+	},
+
+	.probe		= regulator_haptic_probe,
+	.remove		= regulator_haptic_remove,
+};
+module_platform_driver(regulator_haptic_driver);
+
+MODULE_ALIAS("platform:regulator-haptic");
+MODULE_DESCRIPTION("Regulator haptic driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Hyunhee Kim <hyunhee.kim@samsung.com>");
--
1.7.9.5