drivers/leds/leds-bd2802.c - maze/linux - Git at Google

 /*
  * leds-bd2802.c - RGB LED Driver
  *
  * Copyright (C) 2009 Samsung Electronics
  * Kim Kyuwon <q1.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.
  *
  * Datasheet: http://www.rohm.com/products/databook/driver/pdf/bd2802gu-e.pdf
  *
  */

 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/gpio.h>
 #include <linux/delay.h>
 #include <linux/leds.h>
 #include <linux/leds-bd2802.h>


 #define LED_CTL(rgb2en, rgb1en) ((rgb2en) << 4 | ((rgb1en) << 0))

 #define BD2802_LED_OFFSET		0xa
 #define BD2802_COLOR_OFFSET		0x3

 #define BD2802_REG_CLKSETUP 		0x00
 #define BD2802_REG_CONTROL 		0x01
 #define BD2802_REG_HOURSETUP		0x02
 #define BD2802_REG_CURRENT1SETUP	0x03
 #define BD2802_REG_CURRENT2SETUP	0x04
 #define BD2802_REG_WAVEPATTERN		0x05

 #define BD2802_CURRENT_032		0x10 /* 3.2mA */
 #define BD2802_CURRENT_000		0x00 /* 0.0mA */

 #define BD2802_PATTERN_FULL		0x07
 #define BD2802_PATTERN_HALF		0x03

 enum led_ids {
 	LED1,
 	LED2,
 	LED_NUM,
 };

 enum led_colors {
 	RED,
 	GREEN,
 	BLUE,
 };

 enum led_bits {
 	BD2802_OFF,
 	BD2802_BLINK,
 	BD2802_ON,
 };

 /*
  * State '0' : 'off'
  * State '1' : 'blink'
  * State '2' : 'on'.
  */
 struct led_state {
 	unsigned r:2;
 	unsigned g:2;
 	unsigned b:2;
 };

 struct bd2802_led {
 	struct bd2802_led_platform_data	*pdata;
 	struct i2c_client		*client;
 	struct rw_semaphore		rwsem;
 	struct work_struct		work;

 	struct led_state		led[2];

 	/*
 	 * Making led_classdev as array is not recommended, because array
 	 * members prevent using 'container_of' macro. So repetitive works
 	 * are needed.
 	 */
 	struct led_classdev		cdev_led1r;
 	struct led_classdev		cdev_led1g;
 	struct led_classdev		cdev_led1b;
 	struct led_classdev		cdev_led2r;
 	struct led_classdev		cdev_led2g;
 	struct led_classdev		cdev_led2b;

 	/*
 	 * Advanced Configuration Function(ADF) mode:
 	 * In ADF mode, user can set registers of BD2802GU directly,
 	 * therefore BD2802GU doesn't enter reset state.
 	 */
 	int 				adf_on;

 	enum led_ids			led_id;
 	enum led_colors			color;
 	enum led_bits			state;
 };


 /*--------------------------------------------------------------*/
 /*	BD2802GU helper functions					*/
 /*--------------------------------------------------------------*/

 static inline int bd2802_is_rgb_off(struct bd2802_led *led, enum led_ids id,
 							enum led_colors color)
 {
 	switch (color) {
 	case RED:
 		return !led->led[id].r;
 	case GREEN:
 		return !led->led[id].g;
 	case BLUE:
 		return !led->led[id].b;
 	default:
 		dev_err(&led->client->dev, "%s: Invalid color\n", __func__);
 		return -EINVAL;
 	}
 }

 static inline int bd2802_is_led_off(struct bd2802_led *led, enum led_ids id)
 {
 	if (led->led[id].r || led->led[id].g || led->led[id].b)
 		return 0;

 	return 1;
 }

 static inline int bd2802_is_all_off(struct bd2802_led *led)
 {
 	int i;

 	for (i = 0; i < LED_NUM; i++)
 		if (!bd2802_is_led_off(led, i))
 			return 0;

 	return 1;
 }

 static inline u8 bd2802_get_base_offset(enum led_ids id, enum led_colors color)
 {
 	return id * BD2802_LED_OFFSET + color * BD2802_COLOR_OFFSET;
 }

 static inline u8 bd2802_get_reg_addr(enum led_ids id, enum led_colors color,
 								u8 reg_offset)
 {
 	return reg_offset + bd2802_get_base_offset(id, color);
 }


 /*--------------------------------------------------------------*/
 /*	BD2802GU core functions					*/
 /*--------------------------------------------------------------*/

 static int bd2802_write_byte(struct i2c_client *client, u8 reg, u8 val)
 {
 	int ret = i2c_smbus_write_byte_data(client, reg, val);
 	if (ret >= 0)
 		return 0;

 	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
 						__func__, reg, val, ret);

 	return ret;
 }

 static void bd2802_update_state(struct bd2802_led *led, enum led_ids id,
 				enum led_colors color, enum led_bits led_bit)
 {
 	int i;
 	u8 value;

 	for (i = 0; i < LED_NUM; i++) {
 		if (i == id) {
 			switch (color) {
 			case RED:
 				led->led[i].r = led_bit;
 				break;
 			case GREEN:
 				led->led[i].g = led_bit;
 				break;
 			case BLUE:
 				led->led[i].b = led_bit;
 				break;
 			default:
 				dev_err(&led->client->dev,
 					"%s: Invalid color\n", __func__);
 				return;
 			}
 		}
 	}

 	if (led_bit == BD2802_BLINK || led_bit == BD2802_ON)
 		return;

 	if (!bd2802_is_led_off(led, id))
 		return;

 	if (bd2802_is_all_off(led) && !led->adf_on) {
 		gpio_set_value(led->pdata->reset_gpio, 0);
 		return;
 	}

 	/*
 	 * In this case, other led is turned on, and current led is turned
 	 * off. So set RGB LED Control register to stop the current RGB LED
 	 */
 	value = (id == LED1) ? LED_CTL(1, 0) : LED_CTL(0, 1);
 	bd2802_write_byte(led->client, BD2802_REG_CONTROL, value);
 }

 static void bd2802_configure(struct bd2802_led *led)
 {
 	struct bd2802_led_platform_data *pdata = led->pdata;
 	u8 reg;

 	reg = bd2802_get_reg_addr(LED1, RED, BD2802_REG_HOURSETUP);
 	bd2802_write_byte(led->client, reg, pdata->rgb_time);

 	reg = bd2802_get_reg_addr(LED2, RED, BD2802_REG_HOURSETUP);
 	bd2802_write_byte(led->client, reg, pdata->rgb_time);
 }

 static void bd2802_reset_cancel(struct bd2802_led *led)
 {
 	gpio_set_value(led->pdata->reset_gpio, 1);
 	udelay(100);
 	bd2802_configure(led);
 }

 static void bd2802_enable(struct bd2802_led *led, enum led_ids id)
 {
 	enum led_ids other_led = (id == LED1) ? LED2 : LED1;
 	u8 value, other_led_on;

 	other_led_on = !bd2802_is_led_off(led, other_led);
 	if (id == LED1)
 		value = LED_CTL(other_led_on, 1);
 	else
 		value = LED_CTL(1 , other_led_on);

 	bd2802_write_byte(led->client, BD2802_REG_CONTROL, value);
 }

 static void bd2802_set_on(struct bd2802_led *led, enum led_ids id,
 							enum led_colors color)
 {
 	u8 reg;

 	if (bd2802_is_all_off(led) && !led->adf_on)
 		bd2802_reset_cancel(led);

 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT1SETUP);
 	bd2802_write_byte(led->client, reg, BD2802_CURRENT_032);
 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT2SETUP);
 	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);
 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_WAVEPATTERN);
 	bd2802_write_byte(led->client, reg, BD2802_PATTERN_FULL);

 	bd2802_enable(led, id);
 	bd2802_update_state(led, id, color, BD2802_ON);
 }

 static void bd2802_set_blink(struct bd2802_led *led, enum led_ids id,
 							enum led_colors color)
 {
 	u8 reg;

 	if (bd2802_is_all_off(led) && !led->adf_on)
 		bd2802_reset_cancel(led);

 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT1SETUP);
 	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);
 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT2SETUP);
 	bd2802_write_byte(led->client, reg, BD2802_CURRENT_032);
 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_WAVEPATTERN);
 	bd2802_write_byte(led->client, reg, BD2802_PATTERN_HALF);

 	bd2802_enable(led, id);
 	bd2802_update_state(led, id, color, BD2802_BLINK);
 }

 static void bd2802_turn_on(struct bd2802_led *led, enum led_ids id,
 				enum led_colors color, enum led_bits led_bit)
 {
 	if (led_bit == BD2802_OFF) {
 		dev_err(&led->client->dev,
 					"Only 'blink' and 'on' are allowed\n");
 		return;
 	}

 	if (led_bit == BD2802_BLINK)
 		bd2802_set_blink(led, id, color);
 	else
 		bd2802_set_on(led, id, color);
 }

 static void bd2802_turn_off(struct bd2802_led *led, enum led_ids id,
 							enum led_colors color)
 {
 	u8 reg;

 	if (bd2802_is_rgb_off(led, id, color))
 		return;

 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT1SETUP);
 	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);
 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT2SETUP);
 	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);

 	bd2802_update_state(led, id, color, BD2802_OFF);
 }

 static void bd2802_restore_state(struct bd2802_led *led)
 {
 	int i;

 	for (i = 0; i < LED_NUM; i++) {
 		if (led->led[i].r)
 			bd2802_turn_on(led, i, RED, led->led[i].r);
 		if (led->led[i].g)
 			bd2802_turn_on(led, i, GREEN, led->led[i].g);
 		if (led->led[i].b)
 			bd2802_turn_on(led, i, BLUE, led->led[i].b);
 	}
 }

 #define BD2802_SET_REGISTER(reg_addr, reg_name)				\
 static ssize_t bd2802_store_reg##reg_addr(struct device *dev,		\
 	struct device_attribute *attr, const char *buf, size_t count)	\
 {									\
 	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));\
 	unsigned long val;						\
 	int ret;							\
 	if (!count)							\
 		return -EINVAL;						\
 	ret = strict_strtoul(buf, 16, &val);				\
 	if (ret)							\
 		return ret;						\
 	down_write(&led->rwsem);					\
 	bd2802_write_byte(led->client, reg_addr, (u8) val);		\
 	up_write(&led->rwsem);						\
 	return count;							\
 }									\
 static struct device_attribute bd2802_reg##reg_addr##_attr = {		\
 	.attr = {.name = reg_name, .mode = 0644, .owner = THIS_MODULE},	\
 	.store = bd2802_store_reg##reg_addr,				\
 };

 BD2802_SET_REGISTER(0x00, "0x00");
 BD2802_SET_REGISTER(0x01, "0x01");
 BD2802_SET_REGISTER(0x02, "0x02");
 BD2802_SET_REGISTER(0x03, "0x03");
 BD2802_SET_REGISTER(0x04, "0x04");
 BD2802_SET_REGISTER(0x05, "0x05");
 BD2802_SET_REGISTER(0x06, "0x06");
 BD2802_SET_REGISTER(0x07, "0x07");
 BD2802_SET_REGISTER(0x08, "0x08");
 BD2802_SET_REGISTER(0x09, "0x09");
 BD2802_SET_REGISTER(0x0a, "0x0a");
 BD2802_SET_REGISTER(0x0b, "0x0b");
 BD2802_SET_REGISTER(0x0c, "0x0c");
 BD2802_SET_REGISTER(0x0d, "0x0d");
 BD2802_SET_REGISTER(0x0e, "0x0e");
 BD2802_SET_REGISTER(0x0f, "0x0f");
 BD2802_SET_REGISTER(0x10, "0x10");
 BD2802_SET_REGISTER(0x11, "0x11");
 BD2802_SET_REGISTER(0x12, "0x12");
 BD2802_SET_REGISTER(0x13, "0x13");
 BD2802_SET_REGISTER(0x14, "0x14");
 BD2802_SET_REGISTER(0x15, "0x15");

 static struct device_attribute *bd2802_addr_attributes[] = {
 	&bd2802_reg0x00_attr,
 	&bd2802_reg0x01_attr,
 	&bd2802_reg0x02_attr,
 	&bd2802_reg0x03_attr,
 	&bd2802_reg0x04_attr,
 	&bd2802_reg0x05_attr,
 	&bd2802_reg0x06_attr,
 	&bd2802_reg0x07_attr,
 	&bd2802_reg0x08_attr,
 	&bd2802_reg0x09_attr,
 	&bd2802_reg0x0a_attr,
 	&bd2802_reg0x0b_attr,
 	&bd2802_reg0x0c_attr,
 	&bd2802_reg0x0d_attr,
 	&bd2802_reg0x0e_attr,
 	&bd2802_reg0x0f_attr,
 	&bd2802_reg0x10_attr,
 	&bd2802_reg0x11_attr,
 	&bd2802_reg0x12_attr,
 	&bd2802_reg0x13_attr,
 	&bd2802_reg0x14_attr,
 	&bd2802_reg0x15_attr,
 };

 static void bd2802_enable_adv_conf(struct bd2802_led *led)
 {
 	int i, ret;

 	for (i = 0; i < ARRAY_SIZE(bd2802_addr_attributes); i++) {
 		ret = device_create_file(&led->client->dev,
 						bd2802_addr_attributes[i]);
 		if (ret) {
 			dev_err(&led->client->dev, "failed to sysfs file %s\n",
 					bd2802_addr_attributes[i]->attr.name);
 			goto failed_remove_files;
 		}
 	}

 	if (bd2802_is_all_off(led))
 		bd2802_reset_cancel(led);

 	led->adf_on = 1;

 	return;

 failed_remove_files:
 	for (i--; i >= 0; i--)
 		device_remove_file(&led->client->dev,
 						bd2802_addr_attributes[i]);
 }

 static void bd2802_disable_adv_conf(struct bd2802_led *led)
 {
 	int i;

 	for (i = 0; i < ARRAY_SIZE(bd2802_addr_attributes); i++)
 		device_remove_file(&led->client->dev,
 						bd2802_addr_attributes[i]);

 	if (bd2802_is_all_off(led))
 		gpio_set_value(led->pdata->reset_gpio, 0);

 	led->adf_on = 0;
 }

 static ssize_t bd2802_show_adv_conf(struct device *dev,
 	struct device_attribute *attr, char *buf)
 {
 	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));
 	ssize_t ret;

 	down_read(&led->rwsem);
 	if (led->adf_on)
 		ret = sprintf(buf, "on\n");
 	else
 		ret = sprintf(buf, "off\n");
 	up_read(&led->rwsem);

 	return ret;
 }

 static ssize_t bd2802_store_adv_conf(struct device *dev,
 	struct device_attribute *attr, const char *buf, size_t count)
 {
 	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));

 	if (!count)
 		return -EINVAL;

 	down_write(&led->rwsem);
 	if (!led->adf_on && !strncmp(buf, "on", 2))
 		bd2802_enable_adv_conf(led);
 	else if (led->adf_on && !strncmp(buf, "off", 3))
 		bd2802_disable_adv_conf(led);
 	up_write(&led->rwsem);

 	return count;
 }

 static struct device_attribute bd2802_adv_conf_attr = {
 	.attr = {
 		.name = "advanced_configuration",
 		.mode = 0644,
 		.owner = THIS_MODULE
 	},
 	.show = bd2802_show_adv_conf,
 	.store = bd2802_store_adv_conf,
 };

 static void bd2802_led_work(struct work_struct *work)
 {
 	struct bd2802_led *led = container_of(work, struct bd2802_led, work);

 	if (led->state)
 		bd2802_turn_on(led, led->led_id, led->color, led->state);
 	else
 		bd2802_turn_off(led, led->led_id, led->color);
 }

 #define BD2802_CONTROL_RGBS(name, id, clr)				\
 static void bd2802_set_##name##_brightness(struct led_classdev *led_cdev,\
 					enum led_brightness value)	\
 {									\
 	struct bd2802_led *led =					\
 		container_of(led_cdev, struct bd2802_led, cdev_##name);	\
 	led->led_id = id;						\
 	led->color = clr;						\
 	if (value == LED_OFF)						\
 		led->state = BD2802_OFF;				\
 	else								\
 		led->state = BD2802_ON;					\
 	schedule_work(&led->work);					\
 }									\
 static int bd2802_set_##name##_blink(struct led_classdev *led_cdev,	\
 		unsigned long *delay_on, unsigned long *delay_off)	\
 {									\
 	struct bd2802_led *led =					\
 		container_of(led_cdev, struct bd2802_led, cdev_##name);	\
 	if (*delay_on == 0 || *delay_off == 0)				\
 		return -EINVAL;						\
 	led->led_id = id;						\
 	led->color = clr;						\
 	led->state = BD2802_BLINK;					\
 	schedule_work(&led->work);					\
 	return 0;							\
 }

 BD2802_CONTROL_RGBS(led1r, LED1, RED);
 BD2802_CONTROL_RGBS(led1g, LED1, GREEN);
 BD2802_CONTROL_RGBS(led1b, LED1, BLUE);
 BD2802_CONTROL_RGBS(led2r, LED2, RED);
 BD2802_CONTROL_RGBS(led2g, LED2, GREEN);
 BD2802_CONTROL_RGBS(led2b, LED2, BLUE);

 static int bd2802_register_led_classdev(struct bd2802_led *led)
 {
 	int ret;

 	INIT_WORK(&led->work, bd2802_led_work);

 	led->cdev_led1r.name = "led1_R";
 	led->cdev_led1r.brightness = LED_OFF;
 	led->cdev_led1r.brightness_set = bd2802_set_led1r_brightness;
 	led->cdev_led1r.blink_set = bd2802_set_led1r_blink;
 	led->cdev_led1r.flags |= LED_CORE_SUSPENDRESUME;

 	ret = led_classdev_register(&led->client->dev, &led->cdev_led1r);
 	if (ret < 0) {
 		dev_err(&led->client->dev, "couldn't register LED %s\n",
 							led->cdev_led1r.name);
 		goto failed_unregister_led1_R;
 	}

 	led->cdev_led1g.name = "led1_G";
 	led->cdev_led1g.brightness = LED_OFF;
 	led->cdev_led1g.brightness_set = bd2802_set_led1g_brightness;
 	led->cdev_led1g.blink_set = bd2802_set_led1g_blink;
 	led->cdev_led1g.flags |= LED_CORE_SUSPENDRESUME;

 	ret = led_classdev_register(&led->client->dev, &led->cdev_led1g);
 	if (ret < 0) {
 		dev_err(&led->client->dev, "couldn't register LED %s\n",
 							led->cdev_led1g.name);
 		goto failed_unregister_led1_G;
 	}

 	led->cdev_led1b.name = "led1_B";
 	led->cdev_led1b.brightness = LED_OFF;
 	led->cdev_led1b.brightness_set = bd2802_set_led1b_brightness;
 	led->cdev_led1b.blink_set = bd2802_set_led1b_blink;
 	led->cdev_led1b.flags |= LED_CORE_SUSPENDRESUME;

 	ret = led_classdev_register(&led->client->dev, &led->cdev_led1b);
 	if (ret < 0) {
 		dev_err(&led->client->dev, "couldn't register LED %s\n",
 							led->cdev_led1b.name);
 		goto failed_unregister_led1_B;
 	}

 	led->cdev_led2r.name = "led2_R";
 	led->cdev_led2r.brightness = LED_OFF;
 	led->cdev_led2r.brightness_set = bd2802_set_led2r_brightness;
 	led->cdev_led2r.blink_set = bd2802_set_led2r_blink;
 	led->cdev_led2r.flags |= LED_CORE_SUSPENDRESUME;

 	ret = led_classdev_register(&led->client->dev, &led->cdev_led2r);
 	if (ret < 0) {
 		dev_err(&led->client->dev, "couldn't register LED %s\n",
 							led->cdev_led2r.name);
 		goto failed_unregister_led2_R;
 	}

 	led->cdev_led2g.name = "led2_G";
 	led->cdev_led2g.brightness = LED_OFF;
 	led->cdev_led2g.brightness_set = bd2802_set_led2g_brightness;
 	led->cdev_led2g.blink_set = bd2802_set_led2g_blink;
 	led->cdev_led2g.flags |= LED_CORE_SUSPENDRESUME;

 	ret = led_classdev_register(&led->client->dev, &led->cdev_led2g);
 	if (ret < 0) {
 		dev_err(&led->client->dev, "couldn't register LED %s\n",
 							led->cdev_led2g.name);
 		goto failed_unregister_led2_G;
 	}

 	led->cdev_led2b.name = "led2_B";
 	led->cdev_led2b.brightness = LED_OFF;
 	led->cdev_led2b.brightness_set = bd2802_set_led2b_brightness;
 	led->cdev_led2b.blink_set = bd2802_set_led2b_blink;
 	led->cdev_led2b.flags |= LED_CORE_SUSPENDRESUME;

 	ret = led_classdev_register(&led->client->dev, &led->cdev_led2b);
 	if (ret < 0) {
 		dev_err(&led->client->dev, "couldn't register LED %s\n",
 							led->cdev_led2b.name);
 		goto failed_unregister_led2_B;
 	}

 	return 0;

 failed_unregister_led2_B:
 	led_classdev_unregister(&led->cdev_led2g);
 failed_unregister_led2_G:
 	led_classdev_unregister(&led->cdev_led2r);
 failed_unregister_led2_R:
 	led_classdev_unregister(&led->cdev_led1b);
 failed_unregister_led1_B:
 	led_classdev_unregister(&led->cdev_led1g);
 failed_unregister_led1_G:
 	led_classdev_unregister(&led->cdev_led1r);
 failed_unregister_led1_R:

 	return ret;
 }

 static void bd2802_unregister_led_classdev(struct bd2802_led *led)
 {
 	cancel_work_sync(&led->work);
 	led_classdev_unregister(&led->cdev_led1r);
 }

 static int __devinit bd2802_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
 	struct bd2802_led *led;
 	struct bd2802_led_platform_data *pdata;
 	int ret;

 	led = kzalloc(sizeof(struct bd2802_led), GFP_KERNEL);
 	if (!led) {
 		dev_err(&client->dev, "failed to allocate driver data\n");
 		return -ENOMEM;
 	}

 	led->client = client;
 	pdata = led->pdata = client->dev.platform_data;
 	i2c_set_clientdata(client, led);

 	/* Configure RESET GPIO (L: RESET, H: RESET cancel) */
 	gpio_request(pdata->reset_gpio, "RGB_RESETB");
 	gpio_direction_output(pdata->reset_gpio, 1);

 	/* Tacss = min 0.1ms */
 	udelay(100);

 	/* Detect BD2802GU */
 	ret = bd2802_write_byte(client, BD2802_REG_CLKSETUP, 0x00);
 	if (ret < 0) {
 		dev_err(&client->dev, "failed to detect device\n");
 		goto failed_free;
 	} else
 		dev_info(&client->dev, "return 0x%02x\n", ret);

 	/* To save the power, reset BD2802 after detecting */
 	gpio_set_value(led->pdata->reset_gpio, 0);

 	init_rwsem(&led->rwsem);

 	ret = device_create_file(&client->dev, &bd2802_adv_conf_attr);
 	if (ret) {
 		dev_err(&client->dev, "failed to create sysfs file %s\n",
 					bd2802_adv_conf_attr.attr.name);
 		goto failed_free;
 	}

 	ret = bd2802_register_led_classdev(led);
 	if (ret < 0)
 		goto failed_unregister_dev_file;

 	return 0;

 failed_unregister_dev_file:
 	device_remove_file(&client->dev, &bd2802_adv_conf_attr);
 failed_free:
 	i2c_set_clientdata(client, NULL);
 	kfree(led);

 	return ret;
 }

 static int __exit bd2802_remove(struct i2c_client *client)
 {
 	struct bd2802_led *led = i2c_get_clientdata(client);

 	bd2802_unregister_led_classdev(led);
 	gpio_set_value(led->pdata->reset_gpio, 0);
 	if (led->adf_on)
 		bd2802_disable_adv_conf(led);
 	device_remove_file(&client->dev, &bd2802_adv_conf_attr);
 	i2c_set_clientdata(client, NULL);
 	kfree(led);

 	return 0;
 }

 static int bd2802_suspend(struct i2c_client *client, pm_message_t mesg)
 {
 	struct bd2802_led *led = i2c_get_clientdata(client);

 	gpio_set_value(led->pdata->reset_gpio, 0);

 	return 0;
 }

 static int bd2802_resume(struct i2c_client *client)
 {
 	struct bd2802_led *led = i2c_get_clientdata(client);

 	if (!bd2802_is_all_off(led) || led->adf_on) {
 		gpio_set_value(led->pdata->reset_gpio, 1);
 		udelay(100);
 		bd2802_restore_state(led);
 	}

 	return 0;
 }

 static const struct i2c_device_id bd2802_id[] = {
 	{ "BD2802", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, bd2802_id);

 static struct i2c_driver bd2802_i2c_driver = {
 	.driver	= {
 		.name	= "BD2802",
 	},
 	.probe		= bd2802_probe,
 	.remove		= __exit_p(bd2802_remove),
 	.suspend	= bd2802_suspend,
 	.resume		= bd2802_resume,
 	.id_table	= bd2802_id,
 };

 static int __init bd2802_init(void)
 {
 	return i2c_add_driver(&bd2802_i2c_driver);
 }
 module_init(bd2802_init);

 static void __exit bd2802_exit(void)
 {
 	i2c_del_driver(&bd2802_i2c_driver);
 }
 module_exit(bd2802_exit);

 MODULE_AUTHOR("Kim Kyuwon <q1.kim@samsung.com>");
 MODULE_DESCRIPTION("BD2802 LED driver");
 MODULE_LICENSE("GPL");
	/*
	* leds-bd2802.c - RGB LED Driver
	*
	* Copyright (C) 2009 Samsung Electronics
	* Kim Kyuwon <q1.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.
	*
	* Datasheet: http://www.rohm.com/products/databook/driver/pdf/bd2802gu-e.pdf
	*
	*/

	#include <linux/module.h>
	#include <linux/i2c.h>
	#include <linux/gpio.h>
	#include <linux/delay.h>
	#include <linux/leds.h>
	#include <linux/leds-bd2802.h>


	#define LED_CTL(rgb2en, rgb1en) ((rgb2en) << 4 \| ((rgb1en) << 0))

	#define BD2802_LED_OFFSET 0xa
	#define BD2802_COLOR_OFFSET 0x3

	#define BD2802_REG_CLKSETUP 0x00
	#define BD2802_REG_CONTROL 0x01
	#define BD2802_REG_HOURSETUP 0x02
	#define BD2802_REG_CURRENT1SETUP 0x03
	#define BD2802_REG_CURRENT2SETUP 0x04
	#define BD2802_REG_WAVEPATTERN 0x05

	#define BD2802_CURRENT_032 0x10 /* 3.2mA */
	#define BD2802_CURRENT_000 0x00 /* 0.0mA */

	#define BD2802_PATTERN_FULL 0x07
	#define BD2802_PATTERN_HALF 0x03

	enum led_ids {
	LED1,
	LED2,
	LED_NUM,
	};

	enum led_colors {
	RED,
	GREEN,
	BLUE,
	};

	enum led_bits {
	BD2802_OFF,
	BD2802_BLINK,
	BD2802_ON,
	};

	/*
	* State '0' : 'off'
	* State '1' : 'blink'
	* State '2' : 'on'.
	*/
	struct led_state {
	unsigned r:2;
	unsigned g:2;
	unsigned b:2;
	};

	struct bd2802_led {
	struct bd2802_led_platform_data *pdata;
	struct i2c_client *client;
	struct rw_semaphore rwsem;
	struct work_struct work;

	struct led_state led[2];

	/*
	* Making led_classdev as array is not recommended, because array
	* members prevent using 'container_of' macro. So repetitive works
	* are needed.
	*/
	struct led_classdev cdev_led1r;
	struct led_classdev cdev_led1g;
	struct led_classdev cdev_led1b;
	struct led_classdev cdev_led2r;
	struct led_classdev cdev_led2g;
	struct led_classdev cdev_led2b;

	/*
	* Advanced Configuration Function(ADF) mode:
	* In ADF mode, user can set registers of BD2802GU directly,
	* therefore BD2802GU doesn't enter reset state.
	*/
	int adf_on;

	enum led_ids led_id;
	enum led_colors color;
	enum led_bits state;
	};


	/--------------------------------------------------------------/
	/* BD2802GU helper functions */
	/--------------------------------------------------------------/

	static inline int bd2802_is_rgb_off(struct bd2802_led *led, enum led_ids id,
	enum led_colors color)
	{
	switch (color) {
	case RED:
	return !led->led[id].r;
	case GREEN:
	return !led->led[id].g;
	case BLUE:
	return !led->led[id].b;
	default:
	dev_err(&led->client->dev, "%s: Invalid color\n", __func__);
	return -EINVAL;
	}
	}

	static inline int bd2802_is_led_off(struct bd2802_led *led, enum led_ids id)
	{
	if (led->led[id].r \|\| led->led[id].g \|\| led->led[id].b)
	return 0;

	return 1;
	}

	static inline int bd2802_is_all_off(struct bd2802_led *led)
	{
	int i;

	for (i = 0; i < LED_NUM; i++)
	if (!bd2802_is_led_off(led, i))
	return 0;

	return 1;
	}

	static inline u8 bd2802_get_base_offset(enum led_ids id, enum led_colors color)
	{
	return id * BD2802_LED_OFFSET + color * BD2802_COLOR_OFFSET;
	}

	static inline u8 bd2802_get_reg_addr(enum led_ids id, enum led_colors color,
	u8 reg_offset)
	{
	return reg_offset + bd2802_get_base_offset(id, color);
	}


	/--------------------------------------------------------------/
	/* BD2802GU core functions */
	/--------------------------------------------------------------/

	static int bd2802_write_byte(struct i2c_client *client, u8 reg, u8 val)
	{
	int ret = i2c_smbus_write_byte_data(client, reg, val);
	if (ret >= 0)
	return 0;

	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
	__func__, reg, val, ret);

	return ret;
	}

	static void bd2802_update_state(struct bd2802_led *led, enum led_ids id,
	enum led_colors color, enum led_bits led_bit)
	{
	int i;
	u8 value;

	for (i = 0; i < LED_NUM; i++) {
	if (i == id) {
	switch (color) {
	case RED:
	led->led[i].r = led_bit;
	break;
	case GREEN:
	led->led[i].g = led_bit;
	break;
	case BLUE:
	led->led[i].b = led_bit;
	break;
	default:
	dev_err(&led->client->dev,
	"%s: Invalid color\n", __func__);
	return;
	}
	}
	}

	if (led_bit == BD2802_BLINK \|\| led_bit == BD2802_ON)
	return;

	if (!bd2802_is_led_off(led, id))
	return;

	if (bd2802_is_all_off(led) && !led->adf_on) {
	gpio_set_value(led->pdata->reset_gpio, 0);
	return;
	}

	/*
	* In this case, other led is turned on, and current led is turned
	* off. So set RGB LED Control register to stop the current RGB LED
	*/
	value = (id == LED1) ? LED_CTL(1, 0) : LED_CTL(0, 1);
	bd2802_write_byte(led->client, BD2802_REG_CONTROL, value);
	}

	static void bd2802_configure(struct bd2802_led *led)
	{
	struct bd2802_led_platform_data *pdata = led->pdata;
	u8 reg;

	reg = bd2802_get_reg_addr(LED1, RED, BD2802_REG_HOURSETUP);
	bd2802_write_byte(led->client, reg, pdata->rgb_time);

	reg = bd2802_get_reg_addr(LED2, RED, BD2802_REG_HOURSETUP);
	bd2802_write_byte(led->client, reg, pdata->rgb_time);
	}

	static void bd2802_reset_cancel(struct bd2802_led *led)
	{
	gpio_set_value(led->pdata->reset_gpio, 1);
	udelay(100);
	bd2802_configure(led);
	}

	static void bd2802_enable(struct bd2802_led *led, enum led_ids id)
	{
	enum led_ids other_led = (id == LED1) ? LED2 : LED1;
	u8 value, other_led_on;

	other_led_on = !bd2802_is_led_off(led, other_led);
	if (id == LED1)
	value = LED_CTL(other_led_on, 1);
	else
	value = LED_CTL(1 , other_led_on);

	bd2802_write_byte(led->client, BD2802_REG_CONTROL, value);
	}

	static void bd2802_set_on(struct bd2802_led *led, enum led_ids id,
	enum led_colors color)
	{
	u8 reg;

	if (bd2802_is_all_off(led) && !led->adf_on)
	bd2802_reset_cancel(led);

	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT1SETUP);
	bd2802_write_byte(led->client, reg, BD2802_CURRENT_032);
	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT2SETUP);
	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);
	reg = bd2802_get_reg_addr(id, color, BD2802_REG_WAVEPATTERN);
	bd2802_write_byte(led->client, reg, BD2802_PATTERN_FULL);

	bd2802_enable(led, id);
	bd2802_update_state(led, id, color, BD2802_ON);
	}

	static void bd2802_set_blink(struct bd2802_led *led, enum led_ids id,
	enum led_colors color)
	{
	u8 reg;

	if (bd2802_is_all_off(led) && !led->adf_on)
	bd2802_reset_cancel(led);

	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT1SETUP);
	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);
	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT2SETUP);
	bd2802_write_byte(led->client, reg, BD2802_CURRENT_032);
	reg = bd2802_get_reg_addr(id, color, BD2802_REG_WAVEPATTERN);
	bd2802_write_byte(led->client, reg, BD2802_PATTERN_HALF);

	bd2802_enable(led, id);
	bd2802_update_state(led, id, color, BD2802_BLINK);
	}

	static void bd2802_turn_on(struct bd2802_led *led, enum led_ids id,
	enum led_colors color, enum led_bits led_bit)
	{
	if (led_bit == BD2802_OFF) {
	dev_err(&led->client->dev,
	"Only 'blink' and 'on' are allowed\n");
	return;
	}

	if (led_bit == BD2802_BLINK)
	bd2802_set_blink(led, id, color);
	else
	bd2802_set_on(led, id, color);
	}

	static void bd2802_turn_off(struct bd2802_led *led, enum led_ids id,
	enum led_colors color)
	{
	u8 reg;

	if (bd2802_is_rgb_off(led, id, color))
	return;

	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT1SETUP);
	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);
	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT2SETUP);
	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);

	bd2802_update_state(led, id, color, BD2802_OFF);
	}

	static void bd2802_restore_state(struct bd2802_led *led)
	{
	int i;

	for (i = 0; i < LED_NUM; i++) {
	if (led->led[i].r)
	bd2802_turn_on(led, i, RED, led->led[i].r);
	if (led->led[i].g)
	bd2802_turn_on(led, i, GREEN, led->led[i].g);
	if (led->led[i].b)
	bd2802_turn_on(led, i, BLUE, led->led[i].b);
	}
	}

	#define BD2802_SET_REGISTER(reg_addr, reg_name) \
	static ssize_t bd2802_store_reg##reg_addr(struct device *dev, \
	struct device_attribute attr, const char buf, size_t count) \
	{ \
	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));\
	unsigned long val; \
	int ret; \
	if (!count) \
	return -EINVAL; \
	ret = strict_strtoul(buf, 16, &val); \
	if (ret) \
	return ret; \
	down_write(&led->rwsem); \
	bd2802_write_byte(led->client, reg_addr, (u8) val); \
	up_write(&led->rwsem); \
	return count; \
	} \
	static struct device_attribute bd2802_reg##reg_addr##_attr = { \
	.attr = {.name = reg_name, .mode = 0644, .owner = THIS_MODULE}, \
	.store = bd2802_store_reg##reg_addr, \
	};

	BD2802_SET_REGISTER(0x00, "0x00");
	BD2802_SET_REGISTER(0x01, "0x01");
	BD2802_SET_REGISTER(0x02, "0x02");
	BD2802_SET_REGISTER(0x03, "0x03");
	BD2802_SET_REGISTER(0x04, "0x04");
	BD2802_SET_REGISTER(0x05, "0x05");
	BD2802_SET_REGISTER(0x06, "0x06");
	BD2802_SET_REGISTER(0x07, "0x07");
	BD2802_SET_REGISTER(0x08, "0x08");
	BD2802_SET_REGISTER(0x09, "0x09");
	BD2802_SET_REGISTER(0x0a, "0x0a");
	BD2802_SET_REGISTER(0x0b, "0x0b");
	BD2802_SET_REGISTER(0x0c, "0x0c");
	BD2802_SET_REGISTER(0x0d, "0x0d");
	BD2802_SET_REGISTER(0x0e, "0x0e");
	BD2802_SET_REGISTER(0x0f, "0x0f");
	BD2802_SET_REGISTER(0x10, "0x10");
	BD2802_SET_REGISTER(0x11, "0x11");
	BD2802_SET_REGISTER(0x12, "0x12");
	BD2802_SET_REGISTER(0x13, "0x13");
	BD2802_SET_REGISTER(0x14, "0x14");
	BD2802_SET_REGISTER(0x15, "0x15");

	static struct device_attribute *bd2802_addr_attributes[] = {
	&bd2802_reg0x00_attr,
	&bd2802_reg0x01_attr,
	&bd2802_reg0x02_attr,
	&bd2802_reg0x03_attr,
	&bd2802_reg0x04_attr,
	&bd2802_reg0x05_attr,
	&bd2802_reg0x06_attr,
	&bd2802_reg0x07_attr,
	&bd2802_reg0x08_attr,
	&bd2802_reg0x09_attr,
	&bd2802_reg0x0a_attr,
	&bd2802_reg0x0b_attr,
	&bd2802_reg0x0c_attr,
	&bd2802_reg0x0d_attr,
	&bd2802_reg0x0e_attr,
	&bd2802_reg0x0f_attr,
	&bd2802_reg0x10_attr,
	&bd2802_reg0x11_attr,
	&bd2802_reg0x12_attr,
	&bd2802_reg0x13_attr,
	&bd2802_reg0x14_attr,
	&bd2802_reg0x15_attr,
	};

	static void bd2802_enable_adv_conf(struct bd2802_led *led)
	{
	int i, ret;

	for (i = 0; i < ARRAY_SIZE(bd2802_addr_attributes); i++) {
	ret = device_create_file(&led->client->dev,
	bd2802_addr_attributes[i]);
	if (ret) {
	dev_err(&led->client->dev, "failed to sysfs file %s\n",
	bd2802_addr_attributes[i]->attr.name);
	goto failed_remove_files;
	}
	}

	if (bd2802_is_all_off(led))
	bd2802_reset_cancel(led);

	led->adf_on = 1;

	return;

	failed_remove_files:
	for (i--; i >= 0; i--)
	device_remove_file(&led->client->dev,
	bd2802_addr_attributes[i]);
	}

	static void bd2802_disable_adv_conf(struct bd2802_led *led)
	{
	int i;

	for (i = 0; i < ARRAY_SIZE(bd2802_addr_attributes); i++)
	device_remove_file(&led->client->dev,
	bd2802_addr_attributes[i]);

	if (bd2802_is_all_off(led))
	gpio_set_value(led->pdata->reset_gpio, 0);

	led->adf_on = 0;
	}

	static ssize_t bd2802_show_adv_conf(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));
	ssize_t ret;

	down_read(&led->rwsem);
	if (led->adf_on)
	ret = sprintf(buf, "on\n");
	else
	ret = sprintf(buf, "off\n");
	up_read(&led->rwsem);

	return ret;
	}

	static ssize_t bd2802_store_adv_conf(struct device *dev,
	struct device_attribute attr, const char buf, size_t count)
	{
	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));

	if (!count)
	return -EINVAL;

	down_write(&led->rwsem);
	if (!led->adf_on && !strncmp(buf, "on", 2))
	bd2802_enable_adv_conf(led);
	else if (led->adf_on && !strncmp(buf, "off", 3))
	bd2802_disable_adv_conf(led);
	up_write(&led->rwsem);

	return count;
	}

	static struct device_attribute bd2802_adv_conf_attr = {
	.attr = {
	.name = "advanced_configuration",
	.mode = 0644,
	.owner = THIS_MODULE
	},
	.show = bd2802_show_adv_conf,
	.store = bd2802_store_adv_conf,
	};

	static void bd2802_led_work(struct work_struct *work)
	{
	struct bd2802_led *led = container_of(work, struct bd2802_led, work);

	if (led->state)
	bd2802_turn_on(led, led->led_id, led->color, led->state);
	else
	bd2802_turn_off(led, led->led_id, led->color);
	}

	#define BD2802_CONTROL_RGBS(name, id, clr) \
	static void bd2802_set_##name##_brightness(struct led_classdev *led_cdev,\
	enum led_brightness value) \
	{ \
	struct bd2802_led *led = \
	container_of(led_cdev, struct bd2802_led, cdev_##name); \
	led->led_id = id; \
	led->color = clr; \
	if (value == LED_OFF) \
	led->state = BD2802_OFF; \
	else \
	led->state = BD2802_ON; \
	schedule_work(&led->work); \
	} \
	static int bd2802_set_##name##_blink(struct led_classdev *led_cdev, \
	unsigned long delay_on, unsigned long delay_off) \
	{ \
	struct bd2802_led *led = \
	container_of(led_cdev, struct bd2802_led, cdev_##name); \
	if (delay_on == 0 \|\| delay_off == 0) \
	return -EINVAL; \
	led->led_id = id; \
	led->color = clr; \
	led->state = BD2802_BLINK; \
	schedule_work(&led->work); \
	return 0; \
	}

	BD2802_CONTROL_RGBS(led1r, LED1, RED);
	BD2802_CONTROL_RGBS(led1g, LED1, GREEN);
	BD2802_CONTROL_RGBS(led1b, LED1, BLUE);
	BD2802_CONTROL_RGBS(led2r, LED2, RED);
	BD2802_CONTROL_RGBS(led2g, LED2, GREEN);
	BD2802_CONTROL_RGBS(led2b, LED2, BLUE);

	static int bd2802_register_led_classdev(struct bd2802_led *led)
	{
	int ret;

	INIT_WORK(&led->work, bd2802_led_work);

	led->cdev_led1r.name = "led1_R";
	led->cdev_led1r.brightness = LED_OFF;
	led->cdev_led1r.brightness_set = bd2802_set_led1r_brightness;
	led->cdev_led1r.blink_set = bd2802_set_led1r_blink;
	led->cdev_led1r.flags \|= LED_CORE_SUSPENDRESUME;

	ret = led_classdev_register(&led->client->dev, &led->cdev_led1r);
	if (ret < 0) {
	dev_err(&led->client->dev, "couldn't register LED %s\n",
	led->cdev_led1r.name);
	goto failed_unregister_led1_R;
	}

	led->cdev_led1g.name = "led1_G";
	led->cdev_led1g.brightness = LED_OFF;
	led->cdev_led1g.brightness_set = bd2802_set_led1g_brightness;
	led->cdev_led1g.blink_set = bd2802_set_led1g_blink;
	led->cdev_led1g.flags \|= LED_CORE_SUSPENDRESUME;

	ret = led_classdev_register(&led->client->dev, &led->cdev_led1g);
	if (ret < 0) {
	dev_err(&led->client->dev, "couldn't register LED %s\n",
	led->cdev_led1g.name);
	goto failed_unregister_led1_G;
	}

	led->cdev_led1b.name = "led1_B";
	led->cdev_led1b.brightness = LED_OFF;
	led->cdev_led1b.brightness_set = bd2802_set_led1b_brightness;
	led->cdev_led1b.blink_set = bd2802_set_led1b_blink;
	led->cdev_led1b.flags \|= LED_CORE_SUSPENDRESUME;

	ret = led_classdev_register(&led->client->dev, &led->cdev_led1b);
	if (ret < 0) {
	dev_err(&led->client->dev, "couldn't register LED %s\n",
	led->cdev_led1b.name);
	goto failed_unregister_led1_B;
	}

	led->cdev_led2r.name = "led2_R";
	led->cdev_led2r.brightness = LED_OFF;
	led->cdev_led2r.brightness_set = bd2802_set_led2r_brightness;
	led->cdev_led2r.blink_set = bd2802_set_led2r_blink;
	led->cdev_led2r.flags \|= LED_CORE_SUSPENDRESUME;

	ret = led_classdev_register(&led->client->dev, &led->cdev_led2r);
	if (ret < 0) {
	dev_err(&led->client->dev, "couldn't register LED %s\n",
	led->cdev_led2r.name);
	goto failed_unregister_led2_R;
	}

	led->cdev_led2g.name = "led2_G";
	led->cdev_led2g.brightness = LED_OFF;
	led->cdev_led2g.brightness_set = bd2802_set_led2g_brightness;
	led->cdev_led2g.blink_set = bd2802_set_led2g_blink;
	led->cdev_led2g.flags \|= LED_CORE_SUSPENDRESUME;

	ret = led_classdev_register(&led->client->dev, &led->cdev_led2g);
	if (ret < 0) {
	dev_err(&led->client->dev, "couldn't register LED %s\n",
	led->cdev_led2g.name);
	goto failed_unregister_led2_G;
	}

	led->cdev_led2b.name = "led2_B";
	led->cdev_led2b.brightness = LED_OFF;
	led->cdev_led2b.brightness_set = bd2802_set_led2b_brightness;
	led->cdev_led2b.blink_set = bd2802_set_led2b_blink;
	led->cdev_led2b.flags \|= LED_CORE_SUSPENDRESUME;

	ret = led_classdev_register(&led->client->dev, &led->cdev_led2b);
	if (ret < 0) {
	dev_err(&led->client->dev, "couldn't register LED %s\n",
	led->cdev_led2b.name);
	goto failed_unregister_led2_B;
	}

	return 0;

	failed_unregister_led2_B:
	led_classdev_unregister(&led->cdev_led2g);
	failed_unregister_led2_G:
	led_classdev_unregister(&led->cdev_led2r);
	failed_unregister_led2_R:
	led_classdev_unregister(&led->cdev_led1b);
	failed_unregister_led1_B:
	led_classdev_unregister(&led->cdev_led1g);
	failed_unregister_led1_G:
	led_classdev_unregister(&led->cdev_led1r);
	failed_unregister_led1_R:

	return ret;
	}

	static void bd2802_unregister_led_classdev(struct bd2802_led *led)
	{
	cancel_work_sync(&led->work);
	led_classdev_unregister(&led->cdev_led1r);
	}

	static int __devinit bd2802_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct bd2802_led *led;
	struct bd2802_led_platform_data *pdata;
	int ret;

	led = kzalloc(sizeof(struct bd2802_led), GFP_KERNEL);
	if (!led) {
	dev_err(&client->dev, "failed to allocate driver data\n");
	return -ENOMEM;
	}

	led->client = client;
	pdata = led->pdata = client->dev.platform_data;
	i2c_set_clientdata(client, led);

	/* Configure RESET GPIO (L: RESET, H: RESET cancel) */
	gpio_request(pdata->reset_gpio, "RGB_RESETB");
	gpio_direction_output(pdata->reset_gpio, 1);

	/* Tacss = min 0.1ms */
	udelay(100);

	/* Detect BD2802GU */
	ret = bd2802_write_byte(client, BD2802_REG_CLKSETUP, 0x00);
	if (ret < 0) {
	dev_err(&client->dev, "failed to detect device\n");
	goto failed_free;
	} else
	dev_info(&client->dev, "return 0x%02x\n", ret);

	/* To save the power, reset BD2802 after detecting */
	gpio_set_value(led->pdata->reset_gpio, 0);

	init_rwsem(&led->rwsem);

	ret = device_create_file(&client->dev, &bd2802_adv_conf_attr);
	if (ret) {
	dev_err(&client->dev, "failed to create sysfs file %s\n",
	bd2802_adv_conf_attr.attr.name);
	goto failed_free;
	}

	ret = bd2802_register_led_classdev(led);
	if (ret < 0)
	goto failed_unregister_dev_file;

	return 0;

	failed_unregister_dev_file:
	device_remove_file(&client->dev, &bd2802_adv_conf_attr);
	failed_free:
	i2c_set_clientdata(client, NULL);
	kfree(led);

	return ret;
	}

	static int __exit bd2802_remove(struct i2c_client *client)
	{
	struct bd2802_led *led = i2c_get_clientdata(client);

	bd2802_unregister_led_classdev(led);
	gpio_set_value(led->pdata->reset_gpio, 0);
	if (led->adf_on)
	bd2802_disable_adv_conf(led);
	device_remove_file(&client->dev, &bd2802_adv_conf_attr);
	i2c_set_clientdata(client, NULL);
	kfree(led);

	return 0;
	}

	static int bd2802_suspend(struct i2c_client *client, pm_message_t mesg)
	{
	struct bd2802_led *led = i2c_get_clientdata(client);

	gpio_set_value(led->pdata->reset_gpio, 0);

	return 0;
	}

	static int bd2802_resume(struct i2c_client *client)
	{
	struct bd2802_led *led = i2c_get_clientdata(client);

	if (!bd2802_is_all_off(led) \|\| led->adf_on) {
	gpio_set_value(led->pdata->reset_gpio, 1);
	udelay(100);
	bd2802_restore_state(led);
	}

	return 0;
	}

	static const struct i2c_device_id bd2802_id[] = {
	{ "BD2802", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, bd2802_id);

	static struct i2c_driver bd2802_i2c_driver = {
	.driver = {
	.name = "BD2802",
	},
	.probe = bd2802_probe,
	.remove = __exit_p(bd2802_remove),
	.suspend = bd2802_suspend,
	.resume = bd2802_resume,
	.id_table = bd2802_id,
	};

	static int __init bd2802_init(void)
	{
	return i2c_add_driver(&bd2802_i2c_driver);
	}
	module_init(bd2802_init);

	static void __exit bd2802_exit(void)
	{
	i2c_del_driver(&bd2802_i2c_driver);
	}
	module_exit(bd2802_exit);

	MODULE_AUTHOR("Kim Kyuwon <q1.kim@samsung.com>");
	MODULE_DESCRIPTION("BD2802 LED driver");
	MODULE_LICENSE("GPL");