Re: [PATCH v2 3/3] leds: Add ktd2692 flash LED driver

[Jacek Anaszewski <j.anaszewski@samsung.com>]

Hi Ingi,

Thanks for the update. Please find my comments below.

On 03/17/2015 09:45 AM, Ingi Kim wrote:
> This patch adds a driver to support the ktd2692 flash LEDs.
> ktd2692 can control flash current by ExpressWire interface.
>
> Signed-off-by: Ingi Kim <ingi2.kim@samsung.com>
> ---
>   drivers/leds/Kconfig        |   9 +
>   drivers/leds/Makefile       |   1 +
>   drivers/leds/leds-ktd2692.c | 522 ++++++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 532 insertions(+)
>   create mode 100644 drivers/leds/leds-ktd2692.c
>
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 25b320d..9311cfc4 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -498,6 +498,15 @@ config LEDS_MENF21BMC
>   	  This driver can also be built as a module. If so the module
>   	  will be called leds-menf21bmc.
>
> +config LEDS_KTD2692
> +	tristate "Flash LED support for the KTD2692 Driver"
> +	depends on LEDS_CLASS_FLASH && GPIOLIB
> +	help
> +	  This option enables support for the KTD2692 connected through
> +	  ExpressWire Interface. Say Y to enabled these.
> +	  It depends on LEDS_CLASS_FLASH for using flash led (strobe) and
> +	  GPIOLIB for using gpio pin to control Expresswire interface
> +
>   comment "LED driver for blink(1) USB RGB LED is under Special HID drivers (HID_THINGM)"
>
>   config LEDS_BLINKM
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index cbba921..289513b 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -58,6 +58,7 @@ obj-$(CONFIG_LEDS_BLINKM)		+= leds-blinkm.o
>   obj-$(CONFIG_LEDS_SYSCON)		+= leds-syscon.o
>   obj-$(CONFIG_LEDS_VERSATILE)		+= leds-versatile.o
>   obj-$(CONFIG_LEDS_MENF21BMC)		+= leds-menf21bmc.o
> +obj-$(CONFIG_LEDS_KTD2692)		+= leds-ktd2692.o
>
>   # LED SPI Drivers
>   obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o
> diff --git a/drivers/leds/leds-ktd2692.c b/drivers/leds/leds-ktd2692.c
> new file mode 100644
> index 0000000..8aa339c
> --- /dev/null
> +++ b/drivers/leds/leds-ktd2692.c
> @@ -0,0 +1,522 @@
> +/*
> + * LED driver : leds-ktd2692.c
> + *
> + * Copyright (C) 2015 Samsung Electronics
> + * Ingi Kim <ingi2.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/delay.h>
> +#include <linux/err.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/led-class-flash.h>

Please keep alphabetical order - 'l' is before 'm'.

> +#include <linux/of_gpio.h>
> +#include <linux/platform_device.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/workqueue.h>
> +
> +#define GET_BIT(bit, val)			(((val) >> (bit)) & 0x01)
> +
> +/* Value related the flash timeout */
> +#define KTD2692_FLASH_TM_LEVELS			8
> +#define KTD2692_DEFAULT_FLASH_TM_US		1049000
> +#define KTD2692_MAX_FLASH_TM_US			1835000
> +
> +/* Macro for getting offset of flash timeout */
> +#define GET_TIMEOUT_OFFSET(timeout, step)	((timeout) / (step))
> +
> +/* Adjust a multiple of brightness */
> +#define KTD2692_BRIGHTNESS_RANGE_255_TO_16(x)	(((x) >> 4) & 0x0F)
> +#define KTD2692_BRIGHTNESS_RANGE_255_TO_8(x)	(((x) >> 5) & 0x0F)
> +#define KTD2692_BRIGHTNESS_RANGE_255_TO_4(x)	(((x) >> 6) & 0x0F)
> +
> +/* Base register address */
> +#define KTD2692_REG_LVP_BASE			0x00
> +#define KTD2692_REG_FLASH_TIMEOUT_BASE		0x20
> +#define KTD2692_REG_MIN_CURRENT_SET_BASE	0x40
> +#define KTD2692_REG_MOVIE_CURRENT_BASE		0x60
> +#define KTD2692_REG_FLASH_CURRENT_BASE		0x80
> +#define KTD2692_REG_MODE_BASE			0xA0
> +
> +/* Set bit coding time for expresswire interface */
> +#define KTD2692_TIME_RESET_US			700
> +#define KTD2692_TIME_DATA_START_TIME_US		10
> +#define KTD2692_TIME_HIGH_END_OF_DATA_US	350
> +#define KTD2692_TIME_LOW_END_OF_DATA_US		10
> +#define KTD2692_TIME_SHORT_BITSET_US		4
> +#define KTD2692_TIME_LONG_BITSET_US		12
> +
> +/* KTD2692 default length of name */
> +#define KTD2692_NAME_LENGTH			20
> +
> +/* KTD2692 default name */
> +#define KTD2692_DEFAULT_NAME			"ktd2692"
> +
> +enum ktd2692_bitset {
> +	KTD2692_LOW = 0,
> +	KTD2692_HIGH,
> +};
> +
> +/* Low Voltage Protection Setting */
> +enum ktd2692_lvp_setting {
> +	KTD2692_LVP_DISABLE = 0,
> +	KTD2692_LVP_3_2V,
> +	KTD2692_LVP_3_3V,
> +	KTD2692_LVP_3_4V,		/* default */
> +	KTD2692_LVP_3_5V,
> +	KTD2692_LVP_3_6V,
> +	KTD2692_LVP_3_7V,
> +	KTD2692_LVP_3_8V,
> +};
> +
> +/* Flash Timeout Setting (msec) */
> +enum ktd2692_timeout_setting {
> +	KTD2692_TIMEOUT_DISABLE = 0,
> +	KTD2692_TIMEOUT_262ms,
> +	KTD2692_TIMEOUT_524ms,
> +	KTD2692_TIMEOUT_786ms,
> +	KTD2692_TIMEOUT_1049ms,		/* default */
> +	KTD2692_TIMEOUT_1311ms,
> +	KTD2692_TIMEOUT_1573ms,
> +	KTD2692_TIMEOUT_1835ms,
> +};
> +
> +/* Minimum Current Setting for Timer Operating */
> +enum ktd2692_min_current_setting {
> +	KTD2692_MIN_CURRENT_90mA = 0,
> +	KTD2692_MIN_CURRENT_120mA,
> +	KTD2692_MIN_CURRENT_150mA,
> +	KTD2692_MIN_CURRENT_180mA,
> +	KTD2692_MIN_CURRENT_210mA,
> +	KTD2692_MIN_CURRENT_240mA,	/* default */
> +	KTD2692_MIN_CURRENT_270mA,
> +	KTD2692_MIN_CURRENT_300mA,
> +};
> +
> +/* Movie current setting */
> +enum ktd2692_movie_current_setting {
> +	KTD2692_MOVIE_CURRENT_1 = 0,
> +	KTD2692_MOVIE_CURRENT_2,
> +	KTD2692_MOVIE_CURRENT_3,
> +	KTD2692_MOVIE_CURRENT_4,
> +	KTD2692_MOVIE_CURRENT_5,	/* default */
> +	KTD2692_MOVIE_CURRENT_6,
> +	KTD2692_MOVIE_CURRENT_7,
> +	KTD2692_MOVIE_CURRENT_8,
> +	KTD2692_MOVIE_CURRENT_9,
> +	KTD2692_MOVIE_CURRENT_10,
> +	KTD2692_MOVIE_CURRENT_11,
> +	KTD2692_MOVIE_CURRENT_12,
> +	KTD2692_MOVIE_CURRENT_13,
> +	KTD2692_MOVIE_CURRENT_14,
> +	KTD2692_MOVIE_CURRENT_15,
> +	KTD2692_MOVIE_CURRENT_16,
> +};

KTD2692_MOVIE_MODE_CURRENT_* would be more accurate.

> +/* Flash current setting */
> +enum ktd2692_flash_current_setting {
> +	KTD2692_FLASH_CURRENT_1 = 0,
> +	KTD2692_FLASH_CURRENT_2,
> +	KTD2692_FLASH_CURRENT_3,
> +	KTD2692_FLASH_CURRENT_4,
> +	KTD2692_FLASH_CURRENT_5,
> +	KTD2692_FLASH_CURRENT_6,
> +	KTD2692_FLASH_CURRENT_7,
> +	KTD2692_FLASH_CURRENT_8,
> +	KTD2692_FLASH_CURRENT_9,
> +	KTD2692_FLASH_CURRENT_10,
> +	KTD2692_FLASH_CURRENT_11,
> +	KTD2692_FLASH_CURRENT_12,
> +	KTD2692_FLASH_CURRENT_13,
> +	KTD2692_FLASH_CURRENT_14,
> +	KTD2692_FLASH_CURRENT_15,
> +	KTD2692_FLASH_CURRENT_16,	/* default */
> +};

KTD2692_FLASH_MODE_CURRENT_* ?

> +/* Movie / Flash Mode Control */
> +enum ktd2692_mode_setting {
> +	KTD2692_MODE_DISABLE = 0,	/* default */
> +	KTD2692_MODE_MOVIE,
> +	KTD2692_MODE_FLASH,
> +};
> +
> +struct ktd2692_led_settings {
> +	enum ktd2692_lvp_setting lvp;
> +	enum ktd2692_min_current_setting min_current;
> +	enum ktd2692_movie_current_setting movie_current;
> +	enum ktd2692_flash_current_setting flash_current;
> +	enum ktd2692_mode_setting mode;
> +};

I'd rather avoid extensive use of *setting* suffix. It should be
reserved only to struct led_flash_setting, which comprises the
value of given flash setting and its constraints.

Moreover only the 'mode' property from the struct ktd2692_led_settings
needs to be a variable. Please move it to struct ktd2692_context and
remove the struct ktd2692_led_settings.
After that only enum ktd2692_mode_setting type will be needed.
The remaining enums could be turned into macros then to avoid the
impression that there are some variables of their type somewhere.

> +struct ktd2692_flash_timeout_setting {
> +	struct led_flash_setting flash_timeout;
> +};
> +
> +struct ktd2692_context {
> +	struct ktd2692_led_settings setting;
> +	/* Related LED Flash class device */
> +	struct led_classdev_flash fled_cdev;
> +	struct mutex lock;
> +	struct regulator *regulator;
> +	struct work_struct work_brightness_set;
> +
> +	int ctrl_gpio;
> +	u32 flash_timeout_us;

You need flash_timeout_us variable only during probing. Please
use local variable for this.

> +	enum led_brightness torch_brightness;
> +};
> +
> +static struct ktd2692_context *fled_cdev_to_led(
> +				struct led_classdev_flash *fled_cdev)
> +{
> +	return container_of(fled_cdev, struct ktd2692_context, fled_cdev);
> +}
> +
> +static int ktd2692_led_regulator_enable(struct ktd2692_context *led)
> +{
> +	struct led_classdev_flash *fled_cdev = &led->fled_cdev;
> +	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
> +	int ret;
> +
> +	if (regulator_is_enabled(led->regulator) > 0)
> +		return 0;
> +
> +	ret = regulator_enable(led->regulator);
> +	if (ret)
> +		dev_err(led_cdev->dev, "Failed to enable vin:%d\n", ret);
> +
> +	return ret;
> +}
> +
> +static void ktd2692_led_regulator_disable(struct ktd2692_context *led)
> +{
> +	struct led_classdev_flash *fled_cdev = &led->fled_cdev;
> +	struct led_classdev *led_cdev = &fled_cdev->led_cdev;
> +	int ret;
> +
> +	if (!regulator_is_enabled(led->regulator))
> +		return;
> +
> +	ret = regulator_disable(led->regulator);
> +	if (ret)
> +		dev_err(led_cdev->dev, "Failed to disable vin:%d\n", ret);
> +}
> +
> +static void ktd2692_expresswire_start(struct ktd2692_context *led)
> +{
> +	gpio_set_value(led->ctrl_gpio, KTD2692_HIGH);
> +	udelay(KTD2692_TIME_DATA_START_TIME_US);
> +}
> +
> +static void ktd2692_expresswire_reset(struct ktd2692_context *led)
> +{
> +	gpio_set_value(led->ctrl_gpio, KTD2692_LOW);
> +	udelay(KTD2692_TIME_RESET_US);
> +}
> +
> +static void ktd2692_expresswire_end(struct ktd2692_context *led)
> +{
> +	gpio_set_value(led->ctrl_gpio, KTD2692_LOW);
> +	udelay(KTD2692_TIME_LOW_END_OF_DATA_US);
> +	gpio_set_value(led->ctrl_gpio, KTD2692_HIGH);
> +	udelay(KTD2692_TIME_HIGH_END_OF_DATA_US);
> +}
> +
> +static void ktd2692_expresswire_set_bit(struct ktd2692_context *led, bool bit)
> +{
> +	if (bit) {
> +		gpio_set_value(led->ctrl_gpio, KTD2692_LOW);
> +		udelay(KTD2692_TIME_SHORT_BITSET_US);
> +		gpio_set_value(led->ctrl_gpio, KTD2692_HIGH);
> +		udelay(KTD2692_TIME_LONG_BITSET_US);
> +	} else {
> +		gpio_set_value(led->ctrl_gpio, KTD2692_LOW);
> +		udelay(KTD2692_TIME_LONG_BITSET_US);
> +		gpio_set_value(led->ctrl_gpio, KTD2692_HIGH);
> +		udelay(KTD2692_TIME_SHORT_BITSET_US);
> +	}
> +}
> +
> +static void ktd2692_expresswire_write(struct ktd2692_context *led, u8 value)
> +{
> +	int i;
> +
> +	ktd2692_expresswire_start(led);
> +	for (i = 7; i >= 0; i--)
> +		ktd2692_expresswire_set_bit(led, GET_BIT(i, value));
> +	ktd2692_expresswire_end(led);
> +}
> +
> +static void ktd2692_brightness_set(struct ktd2692_context *led,
> +					enum led_brightness brightness)
> +{
> +	mutex_lock(&led->lock);
> +
> +	ktd2692_expresswire_reset(led);
> +
> +	if (brightness == LED_OFF) {
> +		led->setting.mode = KTD2692_MODE_DISABLE;
> +		led->fled_cdev.led_cdev.brightness = LED_OFF;

You don't need to set the brightness here - it is already handled
by the led-core.

> +		goto out;
> +	}
> +
> +	if (brightness < 0 ||
> +		brightness > led->fled_cdev.led_cdev.max_brightness) {
> +		dev_err(led->fled_cdev.led_cdev.dev,
> +			"Invalid brightness %d\n", brightness);
> +		goto out;
> +	}

Limits are also checked by core and LED_OFF is 0.

> +	led->setting.movie_current =
> +			KTD2692_BRIGHTNESS_RANGE_255_TO_8(brightness);
> +	ktd2692_expresswire_write(led, led->setting.movie_current
> +			| KTD2692_REG_MOVIE_CURRENT_BASE);
> +	ktd2692_expresswire_write(led, KTD2692_LVP_DISABLE
> +			| KTD2692_REG_LVP_BASE);
> +	ktd2692_expresswire_write(led, KTD2692_MIN_CURRENT_300mA
> +			| KTD2692_REG_MIN_CURRENT_SET_BASE);
> +	led->setting.mode = KTD2692_MODE_MOVIE;
> +	ktd2692_expresswire_write(led,
> +			led->setting.mode | KTD2692_REG_MODE_BASE);
> +
> +	led->fled_cdev.led_cdev.brightness = brightness;

Please remove the above line. What you get in brightness argument
of this function is led_cdev.brightness. It doesn't need to be
rewritten.

> +out:
> +	mutex_unlock(&led->lock);
> +}
> +
> +static void ktd2692_brightness_set_work(struct work_struct *work)
> +{
> +	struct ktd2692_context *led =
> +		container_of(work, struct ktd2692_context, work_brightness_set);
> +
> +	ktd2692_brightness_set(led, led->torch_brightness);
> +}
> +
> +static void ktd2692_led_brightness_set(struct led_classdev *led_cdev,
> +					enum led_brightness brightness)
> +{
> +	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
> +	struct ktd2692_context *led = fled_cdev_to_led(fled_cdev);
> +
> +	led->torch_brightness = brightness;
> +	schedule_work(&led->work_brightness_set);
> +}
> +
> +static int ktd2692_led_brightness_set_sync(struct led_classdev *led_cdev,
> +					enum led_brightness brightness)
> +{
> +	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
> +	struct ktd2692_context *led = fled_cdev_to_led(fled_cdev);
> +
> +	ktd2692_brightness_set(led, brightness);
> +
> +	return 0;
> +}
> +
> +static enum led_brightness ktd2692_brightness_get(struct led_classdev *led_cdev)
> +{
> +	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev);
> +	struct ktd2692_context *led = fled_cdev_to_led(fled_cdev);
> +
> +	return led->fled_cdev.led_cdev.brightness;
> +}

brightness_get op should be implemented only for devices which
allow to read the current brightness out from the device.

> +static int ktd2692_led_flash_strobe_set(struct led_classdev_flash *fled_cdev,
> +						bool state)
> +{
> +	struct ktd2692_context *led = fled_cdev_to_led(fled_cdev);
> +	struct led_flash_setting *timeout = &fled_cdev->timeout;
> +	u32 flash_tm_reg;
> +
> +	mutex_lock(&led->lock);
> +
> +	ktd2692_expresswire_reset(led);
> +
> +	if (state == 0)
> +		goto out;
> +
> +	led->setting.mode = KTD2692_MODE_FLASH;
> +	flash_tm_reg = GET_TIMEOUT_OFFSET(timeout->val, timeout->step);
> +
> +	ktd2692_expresswire_write(led, led->setting.lvp
> +			| KTD2692_REG_LVP_BASE);
> +	ktd2692_expresswire_write(led, led->setting.min_current
> +			| KTD2692_REG_MIN_CURRENT_SET_BASE);
> +	ktd2692_expresswire_write(led, flash_tm_reg
> +			| KTD2692_REG_FLASH_TIMEOUT_BASE);
> +	ktd2692_expresswire_write(led, led->setting.flash_current
> +			| KTD2692_REG_FLASH_CURRENT_BASE);
> +	ktd2692_expresswire_write(led, led->setting.mode
> +			| KTD2692_REG_MODE_BASE);

Do all these instructions need to be written before each strobe?
Can't it be done on init, and the flash strobe could be
then triggered with AUX pin?


> +	fled_cdev->led_cdev.brightness = LED_OFF;
> +	led->setting.mode = KTD2692_MODE_DISABLE;
> +
> +out:
> +	mutex_unlock(&led->lock);
> +	return 0;
> +}
> +
> +static int ktd2692_led_flash_timeout_set(struct led_classdev_flash *fled_cdev,
> +						u32 timeout)
> +{
> +	struct ktd2692_context *led = fled_cdev_to_led(fled_cdev);
> +
> +	led->fled_cdev.timeout.val = timeout;

Does the flash timeout register need to be rewritten before each strobe?

> +
> +	return 0;
> +}
> +
> +static int ktd2692_parse_dt(struct ktd2692_context *led, struct device *dev)
> +{
> +	struct device_node *np = dev->of_node;
> +	int ret;
> +
> +	led->ctrl_gpio = of_get_named_gpio(np, "ctrl-gpio", 0);
> +	if (!gpio_is_valid(led->ctrl_gpio)) {
> +		dev_err(dev, "no strobe_gpio property found\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = devm_gpio_request_one(dev, led->ctrl_gpio,
> +					GPIOF_OPEN_SOURCE, "ctrl-gpio");
> +	if (ret) {
> +		dev_err(dev, "failed to request ctrl-gpio %d error %d\n",
> +				led->ctrl_gpio, ret);
> +		return ret;
> +	}
> +
> +	ret = of_property_read_u32(np, "flash-timeout-us",
> +				&led->flash_timeout_us);
> +	/* default setting */
> +	if (ret)
> +		led->flash_timeout_us = KTD2692_DEFAULT_FLASH_TM_US;
> +
> +	return 0;
> +}
> +
> +static void ktd2692_init_flash_timeout_set(u32 flash_timeout_us,
> +					struct ktd2692_flash_timeout_setting *s)
> +{
> +	struct led_flash_setting *setting;
> +
> +	setting = &s->flash_timeout;
> +	setting->min = KTD2692_TIMEOUT_DISABLE;
> +	setting->max = KTD2692_MAX_FLASH_TM_US;
> +	setting->step = KTD2692_MAX_FLASH_TM_US / (KTD2692_FLASH_TM_LEVELS - 1);
> +	setting->val = flash_timeout_us;
> +}
> +
> +static const struct led_flash_ops flash_ops = {
> +	.strobe_set = ktd2692_led_flash_strobe_set,
> +	.timeout_set = ktd2692_led_flash_timeout_set,
> +};
> +
> +static int ktd2692_probe(struct platform_device *pdev)
> +{
> +	struct ktd2692_context *led;
> +	struct led_classdev *led_cdev;
> +	struct led_classdev_flash *fled_cdev;
> +	struct ktd2692_flash_timeout_setting timeout_setting;
> +	int ret;
> +
> +	led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
> +	if (!led)
> +		return -ENOMEM;
> +
> +	if (!pdev->dev.of_node)
> +		return -ENXIO;
> +
> +	fled_cdev = &led->fled_cdev;
> +	led_cdev = &fled_cdev->led_cdev;
> +	platform_set_drvdata(pdev, led);
> +
> +	ret = ktd2692_parse_dt(led, &pdev->dev);
> +	if (ret)
> +		return ret;
> +
> +	led->regulator = devm_regulator_get(&pdev->dev, "vin");
> +	if (IS_ERR(led->regulator)) {
> +		dev_err(&pdev->dev, "regulator get failed\n");
> +		ret = PTR_ERR(led->regulator);
> +		led->regulator = NULL;
> +		return ret;
> +	}
> +
> +	ret = ktd2692_led_regulator_enable(led);
> +	if (ret)
> +		goto err_regulator;
> +
> +	ktd2692_init_flash_timeout_set(led->flash_timeout_us, &timeout_setting);
> +	fled_cdev->timeout = timeout_setting.flash_timeout;
> +	fled_cdev->ops = &flash_ops;
> +
> +	led->setting.lvp = KTD2692_LVP_DISABLE;
> +	led->setting.min_current = KTD2692_MIN_CURRENT_240mA;
> +	led->setting.flash_current = KTD2692_FLASH_CURRENT_7;

These can be skipped in favour of constants.

> +	led->setting.mode = KTD2692_MODE_DISABLE;
> +
> +	led_cdev->name = KTD2692_DEFAULT_NAME;
> +	led_cdev->brightness = LED_OFF;
> +	led_cdev->max_brightness = LED_FULL;
> +	led_cdev->brightness_set = ktd2692_led_brightness_set;
> +	led_cdev->brightness_set_sync = ktd2692_led_brightness_set_sync;
> +	led_cdev->brightness_get = ktd2692_brightness_get;
> +	led_cdev->flags |= LED_DEV_CAP_FLASH;
> +	led_cdev->flags |= LED_CORE_SUSPENDRESUME;
> +
> +	INIT_WORK(&led->work_brightness_set, ktd2692_brightness_set_work);
> +
> +	ret = led_classdev_flash_register(&pdev->dev, fled_cdev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "can't register LED %s\n", led_cdev->name);
> +		goto err_register;
> +	}
> +
> +	mutex_init(&led->lock);
> +
> +	return 0;
> +err_register:
> +	cancel_work_sync(&led->work_brightness_set);
> +err_regulator:
> +	ktd2692_led_regulator_disable(led);
> +	platform_set_drvdata(pdev, NULL);
> +	return ret;
> +}
> +
> +static int ktd2692_remove(struct platform_device *pdev)
> +{
> +	struct ktd2692_context *led = platform_get_drvdata(pdev);
> +
> +	cancel_work_sync(&led->work_brightness_set);
> +	led_classdev_flash_unregister(&led->fled_cdev);
> +	ktd2692_led_regulator_disable(led);
> +
> +	mutex_destroy(&led->lock);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id ktd2692_match[] = {
> +	{ .compatible = "kinetic,ktd2692", },
> +	{ /* sentinel */ },
> +};
> +
> +static struct platform_driver ktd2692_driver = {
> +	.driver = {
> +		.name  = "leds-ktd2692",
> +		.of_match_table = ktd2692_match,
> +	},
> +	.probe  = ktd2692_probe,
> +	.remove = ktd2692_remove,
> +};
> +
> +module_platform_driver(ktd2692_driver);
> +
> +MODULE_AUTHOR("Ingi Kim <ingi2.kim@samsung.com>");
> +MODULE_DESCRIPTION("Kinetic KTD2692 LED driver");
> +MODULE_LICENSE("GPL v2");
>


-- 
Best Regards,
Jacek Anaszewski