xref: /openbmc/linux/drivers/leds/leds-bd2802.c (revision 97e6f135)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * leds-bd2802.c - RGB LED Driver
4  *
5  * Copyright (C) 2009 Samsung Electronics
6  * Kim Kyuwon <q1.kim@samsung.com>
7  *
8  * Datasheet: http://www.rohm.com/products/databook/driver/pdf/bd2802gu-e.pdf
9  */
10 
11 #include <linux/module.h>
12 #include <linux/i2c.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/delay.h>
15 #include <linux/leds.h>
16 #include <linux/leds-bd2802.h>
17 #include <linux/slab.h>
18 #include <linux/pm.h>
19 
20 #define LED_CTL(rgb2en, rgb1en) ((rgb2en) << 4 | ((rgb1en) << 0))
21 
22 #define BD2802_LED_OFFSET		0xa
23 #define BD2802_COLOR_OFFSET		0x3
24 
25 #define BD2802_REG_CLKSETUP		0x00
26 #define BD2802_REG_CONTROL		0x01
27 #define BD2802_REG_HOURSETUP		0x02
28 #define BD2802_REG_CURRENT1SETUP	0x03
29 #define BD2802_REG_CURRENT2SETUP	0x04
30 #define BD2802_REG_WAVEPATTERN		0x05
31 
32 #define BD2802_CURRENT_032		0x10 /* 3.2mA */
33 #define BD2802_CURRENT_000		0x00 /* 0.0mA */
34 
35 #define BD2802_PATTERN_FULL		0x07
36 #define BD2802_PATTERN_HALF		0x03
37 
38 enum led_ids {
39 	LED1,
40 	LED2,
41 	LED_NUM,
42 };
43 
44 enum led_colors {
45 	RED,
46 	GREEN,
47 	BLUE,
48 };
49 
50 enum led_bits {
51 	BD2802_OFF,
52 	BD2802_BLINK,
53 	BD2802_ON,
54 };
55 
56 /*
57  * State '0' : 'off'
58  * State '1' : 'blink'
59  * State '2' : 'on'.
60  */
61 struct led_state {
62 	unsigned r:2;
63 	unsigned g:2;
64 	unsigned b:2;
65 };
66 
67 struct bd2802_led {
68 	struct bd2802_led_platform_data	*pdata;
69 	struct i2c_client		*client;
70 	struct gpio_desc		*reset;
71 	struct rw_semaphore		rwsem;
72 
73 	struct led_state		led[2];
74 
75 	/*
76 	 * Making led_classdev as array is not recommended, because array
77 	 * members prevent using 'container_of' macro. So repetitive works
78 	 * are needed.
79 	 */
80 	struct led_classdev		cdev_led1r;
81 	struct led_classdev		cdev_led1g;
82 	struct led_classdev		cdev_led1b;
83 	struct led_classdev		cdev_led2r;
84 	struct led_classdev		cdev_led2g;
85 	struct led_classdev		cdev_led2b;
86 
87 	/*
88 	 * Advanced Configuration Function(ADF) mode:
89 	 * In ADF mode, user can set registers of BD2802GU directly,
90 	 * therefore BD2802GU doesn't enter reset state.
91 	 */
92 	int				adf_on;
93 
94 	enum led_ids			led_id;
95 	enum led_colors			color;
96 	enum led_bits			state;
97 
98 	/* General attributes of RGB LEDs */
99 	int				wave_pattern;
100 	int				rgb_current;
101 };
102 
103 
104 /*--------------------------------------------------------------*/
105 /*	BD2802GU helper functions					*/
106 /*--------------------------------------------------------------*/
107 
108 static inline int bd2802_is_rgb_off(struct bd2802_led *led, enum led_ids id,
109 							enum led_colors color)
110 {
111 	switch (color) {
112 	case RED:
113 		return !led->led[id].r;
114 	case GREEN:
115 		return !led->led[id].g;
116 	case BLUE:
117 		return !led->led[id].b;
118 	default:
119 		dev_err(&led->client->dev, "%s: Invalid color\n", __func__);
120 		return -EINVAL;
121 	}
122 }
123 
124 static inline int bd2802_is_led_off(struct bd2802_led *led, enum led_ids id)
125 {
126 	if (led->led[id].r || led->led[id].g || led->led[id].b)
127 		return 0;
128 
129 	return 1;
130 }
131 
132 static inline int bd2802_is_all_off(struct bd2802_led *led)
133 {
134 	int i;
135 
136 	for (i = 0; i < LED_NUM; i++)
137 		if (!bd2802_is_led_off(led, i))
138 			return 0;
139 
140 	return 1;
141 }
142 
143 static inline u8 bd2802_get_base_offset(enum led_ids id, enum led_colors color)
144 {
145 	return id * BD2802_LED_OFFSET + color * BD2802_COLOR_OFFSET;
146 }
147 
148 static inline u8 bd2802_get_reg_addr(enum led_ids id, enum led_colors color,
149 								u8 reg_offset)
150 {
151 	return reg_offset + bd2802_get_base_offset(id, color);
152 }
153 
154 
155 /*--------------------------------------------------------------*/
156 /*	BD2802GU core functions					*/
157 /*--------------------------------------------------------------*/
158 
159 static int bd2802_write_byte(struct i2c_client *client, u8 reg, u8 val)
160 {
161 	int ret = i2c_smbus_write_byte_data(client, reg, val);
162 	if (ret >= 0)
163 		return 0;
164 
165 	dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
166 						__func__, reg, val, ret);
167 
168 	return ret;
169 }
170 
171 static void bd2802_update_state(struct bd2802_led *led, enum led_ids id,
172 				enum led_colors color, enum led_bits led_bit)
173 {
174 	int i;
175 	u8 value;
176 
177 	for (i = 0; i < LED_NUM; i++) {
178 		if (i == id) {
179 			switch (color) {
180 			case RED:
181 				led->led[i].r = led_bit;
182 				break;
183 			case GREEN:
184 				led->led[i].g = led_bit;
185 				break;
186 			case BLUE:
187 				led->led[i].b = led_bit;
188 				break;
189 			default:
190 				dev_err(&led->client->dev,
191 					"%s: Invalid color\n", __func__);
192 				return;
193 			}
194 		}
195 	}
196 
197 	if (led_bit == BD2802_BLINK || led_bit == BD2802_ON)
198 		return;
199 
200 	if (!bd2802_is_led_off(led, id))
201 		return;
202 
203 	if (bd2802_is_all_off(led) && !led->adf_on) {
204 		gpiod_set_value(led->reset, 1);
205 		return;
206 	}
207 
208 	/*
209 	 * In this case, other led is turned on, and current led is turned
210 	 * off. So set RGB LED Control register to stop the current RGB LED
211 	 */
212 	value = (id == LED1) ? LED_CTL(1, 0) : LED_CTL(0, 1);
213 	bd2802_write_byte(led->client, BD2802_REG_CONTROL, value);
214 }
215 
216 static void bd2802_configure(struct bd2802_led *led)
217 {
218 	struct bd2802_led_platform_data *pdata = led->pdata;
219 	u8 reg;
220 
221 	reg = bd2802_get_reg_addr(LED1, RED, BD2802_REG_HOURSETUP);
222 	bd2802_write_byte(led->client, reg, pdata->rgb_time);
223 
224 	reg = bd2802_get_reg_addr(LED2, RED, BD2802_REG_HOURSETUP);
225 	bd2802_write_byte(led->client, reg, pdata->rgb_time);
226 }
227 
228 static void bd2802_reset_cancel(struct bd2802_led *led)
229 {
230 	gpiod_set_value(led->reset, 0);
231 	udelay(100);
232 	bd2802_configure(led);
233 }
234 
235 static void bd2802_enable(struct bd2802_led *led, enum led_ids id)
236 {
237 	enum led_ids other_led = (id == LED1) ? LED2 : LED1;
238 	u8 value, other_led_on;
239 
240 	other_led_on = !bd2802_is_led_off(led, other_led);
241 	if (id == LED1)
242 		value = LED_CTL(other_led_on, 1);
243 	else
244 		value = LED_CTL(1 , other_led_on);
245 
246 	bd2802_write_byte(led->client, BD2802_REG_CONTROL, value);
247 }
248 
249 static void bd2802_set_on(struct bd2802_led *led, enum led_ids id,
250 							enum led_colors color)
251 {
252 	u8 reg;
253 
254 	if (bd2802_is_all_off(led) && !led->adf_on)
255 		bd2802_reset_cancel(led);
256 
257 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT1SETUP);
258 	bd2802_write_byte(led->client, reg, led->rgb_current);
259 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT2SETUP);
260 	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);
261 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_WAVEPATTERN);
262 	bd2802_write_byte(led->client, reg, BD2802_PATTERN_FULL);
263 
264 	bd2802_enable(led, id);
265 	bd2802_update_state(led, id, color, BD2802_ON);
266 }
267 
268 static void bd2802_set_blink(struct bd2802_led *led, enum led_ids id,
269 							enum led_colors color)
270 {
271 	u8 reg;
272 
273 	if (bd2802_is_all_off(led) && !led->adf_on)
274 		bd2802_reset_cancel(led);
275 
276 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT1SETUP);
277 	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);
278 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT2SETUP);
279 	bd2802_write_byte(led->client, reg, led->rgb_current);
280 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_WAVEPATTERN);
281 	bd2802_write_byte(led->client, reg, led->wave_pattern);
282 
283 	bd2802_enable(led, id);
284 	bd2802_update_state(led, id, color, BD2802_BLINK);
285 }
286 
287 static void bd2802_turn_on(struct bd2802_led *led, enum led_ids id,
288 				enum led_colors color, enum led_bits led_bit)
289 {
290 	if (led_bit == BD2802_OFF) {
291 		dev_err(&led->client->dev,
292 					"Only 'blink' and 'on' are allowed\n");
293 		return;
294 	}
295 
296 	if (led_bit == BD2802_BLINK)
297 		bd2802_set_blink(led, id, color);
298 	else
299 		bd2802_set_on(led, id, color);
300 }
301 
302 static void bd2802_turn_off(struct bd2802_led *led, enum led_ids id,
303 							enum led_colors color)
304 {
305 	u8 reg;
306 
307 	if (bd2802_is_rgb_off(led, id, color))
308 		return;
309 
310 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT1SETUP);
311 	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);
312 	reg = bd2802_get_reg_addr(id, color, BD2802_REG_CURRENT2SETUP);
313 	bd2802_write_byte(led->client, reg, BD2802_CURRENT_000);
314 
315 	bd2802_update_state(led, id, color, BD2802_OFF);
316 }
317 
318 #define BD2802_SET_REGISTER(reg_addr, reg_name)				\
319 static ssize_t bd2802_store_reg##reg_addr(struct device *dev,		\
320 	struct device_attribute *attr, const char *buf, size_t count)	\
321 {									\
322 	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));\
323 	unsigned long val;						\
324 	int ret;							\
325 	if (!count)							\
326 		return -EINVAL;						\
327 	ret = kstrtoul(buf, 16, &val);					\
328 	if (ret)							\
329 		return ret;						\
330 	down_write(&led->rwsem);					\
331 	bd2802_write_byte(led->client, reg_addr, (u8) val);		\
332 	up_write(&led->rwsem);						\
333 	return count;							\
334 }									\
335 static struct device_attribute bd2802_reg##reg_addr##_attr = {		\
336 	.attr = {.name = reg_name, .mode = 0644},			\
337 	.store = bd2802_store_reg##reg_addr,				\
338 };
339 
340 BD2802_SET_REGISTER(0x00, "0x00");
341 BD2802_SET_REGISTER(0x01, "0x01");
342 BD2802_SET_REGISTER(0x02, "0x02");
343 BD2802_SET_REGISTER(0x03, "0x03");
344 BD2802_SET_REGISTER(0x04, "0x04");
345 BD2802_SET_REGISTER(0x05, "0x05");
346 BD2802_SET_REGISTER(0x06, "0x06");
347 BD2802_SET_REGISTER(0x07, "0x07");
348 BD2802_SET_REGISTER(0x08, "0x08");
349 BD2802_SET_REGISTER(0x09, "0x09");
350 BD2802_SET_REGISTER(0x0a, "0x0a");
351 BD2802_SET_REGISTER(0x0b, "0x0b");
352 BD2802_SET_REGISTER(0x0c, "0x0c");
353 BD2802_SET_REGISTER(0x0d, "0x0d");
354 BD2802_SET_REGISTER(0x0e, "0x0e");
355 BD2802_SET_REGISTER(0x0f, "0x0f");
356 BD2802_SET_REGISTER(0x10, "0x10");
357 BD2802_SET_REGISTER(0x11, "0x11");
358 BD2802_SET_REGISTER(0x12, "0x12");
359 BD2802_SET_REGISTER(0x13, "0x13");
360 BD2802_SET_REGISTER(0x14, "0x14");
361 BD2802_SET_REGISTER(0x15, "0x15");
362 
363 static struct device_attribute *bd2802_addr_attributes[] = {
364 	&bd2802_reg0x00_attr,
365 	&bd2802_reg0x01_attr,
366 	&bd2802_reg0x02_attr,
367 	&bd2802_reg0x03_attr,
368 	&bd2802_reg0x04_attr,
369 	&bd2802_reg0x05_attr,
370 	&bd2802_reg0x06_attr,
371 	&bd2802_reg0x07_attr,
372 	&bd2802_reg0x08_attr,
373 	&bd2802_reg0x09_attr,
374 	&bd2802_reg0x0a_attr,
375 	&bd2802_reg0x0b_attr,
376 	&bd2802_reg0x0c_attr,
377 	&bd2802_reg0x0d_attr,
378 	&bd2802_reg0x0e_attr,
379 	&bd2802_reg0x0f_attr,
380 	&bd2802_reg0x10_attr,
381 	&bd2802_reg0x11_attr,
382 	&bd2802_reg0x12_attr,
383 	&bd2802_reg0x13_attr,
384 	&bd2802_reg0x14_attr,
385 	&bd2802_reg0x15_attr,
386 };
387 
388 static void bd2802_enable_adv_conf(struct bd2802_led *led)
389 {
390 	int i, ret;
391 
392 	for (i = 0; i < ARRAY_SIZE(bd2802_addr_attributes); i++) {
393 		ret = device_create_file(&led->client->dev,
394 						bd2802_addr_attributes[i]);
395 		if (ret) {
396 			dev_err(&led->client->dev, "failed: sysfs file %s\n",
397 					bd2802_addr_attributes[i]->attr.name);
398 			goto failed_remove_files;
399 		}
400 	}
401 
402 	if (bd2802_is_all_off(led))
403 		bd2802_reset_cancel(led);
404 
405 	led->adf_on = 1;
406 
407 	return;
408 
409 failed_remove_files:
410 	for (i--; i >= 0; i--)
411 		device_remove_file(&led->client->dev,
412 						bd2802_addr_attributes[i]);
413 }
414 
415 static void bd2802_disable_adv_conf(struct bd2802_led *led)
416 {
417 	int i;
418 
419 	for (i = 0; i < ARRAY_SIZE(bd2802_addr_attributes); i++)
420 		device_remove_file(&led->client->dev,
421 						bd2802_addr_attributes[i]);
422 
423 	if (bd2802_is_all_off(led))
424 		gpiod_set_value(led->reset, 1);
425 
426 	led->adf_on = 0;
427 }
428 
429 static ssize_t bd2802_show_adv_conf(struct device *dev,
430 	struct device_attribute *attr, char *buf)
431 {
432 	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));
433 	ssize_t ret;
434 
435 	down_read(&led->rwsem);
436 	if (led->adf_on)
437 		ret = sprintf(buf, "on\n");
438 	else
439 		ret = sprintf(buf, "off\n");
440 	up_read(&led->rwsem);
441 
442 	return ret;
443 }
444 
445 static ssize_t bd2802_store_adv_conf(struct device *dev,
446 	struct device_attribute *attr, const char *buf, size_t count)
447 {
448 	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));
449 
450 	if (!count)
451 		return -EINVAL;
452 
453 	down_write(&led->rwsem);
454 	if (!led->adf_on && !strncmp(buf, "on", 2))
455 		bd2802_enable_adv_conf(led);
456 	else if (led->adf_on && !strncmp(buf, "off", 3))
457 		bd2802_disable_adv_conf(led);
458 	up_write(&led->rwsem);
459 
460 	return count;
461 }
462 
463 static struct device_attribute bd2802_adv_conf_attr = {
464 	.attr = {
465 		.name = "advanced_configuration",
466 		.mode = 0644,
467 	},
468 	.show = bd2802_show_adv_conf,
469 	.store = bd2802_store_adv_conf,
470 };
471 
472 #define BD2802_CONTROL_ATTR(attr_name, name_str)			\
473 static ssize_t bd2802_show_##attr_name(struct device *dev,		\
474 	struct device_attribute *attr, char *buf)			\
475 {									\
476 	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));\
477 	ssize_t ret;							\
478 	down_read(&led->rwsem);						\
479 	ret = sprintf(buf, "0x%02x\n", led->attr_name);			\
480 	up_read(&led->rwsem);						\
481 	return ret;							\
482 }									\
483 static ssize_t bd2802_store_##attr_name(struct device *dev,		\
484 	struct device_attribute *attr, const char *buf, size_t count)	\
485 {									\
486 	struct bd2802_led *led = i2c_get_clientdata(to_i2c_client(dev));\
487 	unsigned long val;						\
488 	int ret;							\
489 	if (!count)							\
490 		return -EINVAL;						\
491 	ret = kstrtoul(buf, 16, &val);					\
492 	if (ret)							\
493 		return ret;						\
494 	down_write(&led->rwsem);					\
495 	led->attr_name = val;						\
496 	up_write(&led->rwsem);						\
497 	return count;							\
498 }									\
499 static struct device_attribute bd2802_##attr_name##_attr = {		\
500 	.attr = {							\
501 		.name = name_str,					\
502 		.mode = 0644,						\
503 	},								\
504 	.show = bd2802_show_##attr_name,				\
505 	.store = bd2802_store_##attr_name,				\
506 };
507 
508 BD2802_CONTROL_ATTR(wave_pattern, "wave_pattern");
509 BD2802_CONTROL_ATTR(rgb_current, "rgb_current");
510 
511 static struct device_attribute *bd2802_attributes[] = {
512 	&bd2802_adv_conf_attr,
513 	&bd2802_wave_pattern_attr,
514 	&bd2802_rgb_current_attr,
515 };
516 
517 #define BD2802_CONTROL_RGBS(name, id, clr)				\
518 static int bd2802_set_##name##_brightness(struct led_classdev *led_cdev,\
519 					enum led_brightness value)	\
520 {									\
521 	struct bd2802_led *led =					\
522 		container_of(led_cdev, struct bd2802_led, cdev_##name);	\
523 	led->led_id = id;						\
524 	led->color = clr;						\
525 	if (value == LED_OFF) {						\
526 		led->state = BD2802_OFF;				\
527 		bd2802_turn_off(led, led->led_id, led->color);		\
528 	} else {							\
529 		led->state = BD2802_ON;					\
530 		bd2802_turn_on(led, led->led_id, led->color, BD2802_ON);\
531 	}								\
532 	return 0;							\
533 }									\
534 static int bd2802_set_##name##_blink(struct led_classdev *led_cdev,	\
535 		unsigned long *delay_on, unsigned long *delay_off)	\
536 {									\
537 	struct bd2802_led *led =					\
538 		container_of(led_cdev, struct bd2802_led, cdev_##name);	\
539 	if (*delay_on == 0 || *delay_off == 0)				\
540 		return -EINVAL;						\
541 	led->led_id = id;						\
542 	led->color = clr;						\
543 	led->state = BD2802_BLINK;					\
544 	bd2802_turn_on(led, led->led_id, led->color, BD2802_BLINK);	\
545 	return 0;							\
546 }
547 
548 BD2802_CONTROL_RGBS(led1r, LED1, RED);
549 BD2802_CONTROL_RGBS(led1g, LED1, GREEN);
550 BD2802_CONTROL_RGBS(led1b, LED1, BLUE);
551 BD2802_CONTROL_RGBS(led2r, LED2, RED);
552 BD2802_CONTROL_RGBS(led2g, LED2, GREEN);
553 BD2802_CONTROL_RGBS(led2b, LED2, BLUE);
554 
555 static int bd2802_register_led_classdev(struct bd2802_led *led)
556 {
557 	int ret;
558 
559 	led->cdev_led1r.name = "led1_R";
560 	led->cdev_led1r.brightness = LED_OFF;
561 	led->cdev_led1r.brightness_set_blocking = bd2802_set_led1r_brightness;
562 	led->cdev_led1r.blink_set = bd2802_set_led1r_blink;
563 
564 	ret = led_classdev_register(&led->client->dev, &led->cdev_led1r);
565 	if (ret < 0) {
566 		dev_err(&led->client->dev, "couldn't register LED %s\n",
567 							led->cdev_led1r.name);
568 		goto failed_unregister_led1_R;
569 	}
570 
571 	led->cdev_led1g.name = "led1_G";
572 	led->cdev_led1g.brightness = LED_OFF;
573 	led->cdev_led1g.brightness_set_blocking = bd2802_set_led1g_brightness;
574 	led->cdev_led1g.blink_set = bd2802_set_led1g_blink;
575 
576 	ret = led_classdev_register(&led->client->dev, &led->cdev_led1g);
577 	if (ret < 0) {
578 		dev_err(&led->client->dev, "couldn't register LED %s\n",
579 							led->cdev_led1g.name);
580 		goto failed_unregister_led1_G;
581 	}
582 
583 	led->cdev_led1b.name = "led1_B";
584 	led->cdev_led1b.brightness = LED_OFF;
585 	led->cdev_led1b.brightness_set_blocking = bd2802_set_led1b_brightness;
586 	led->cdev_led1b.blink_set = bd2802_set_led1b_blink;
587 
588 	ret = led_classdev_register(&led->client->dev, &led->cdev_led1b);
589 	if (ret < 0) {
590 		dev_err(&led->client->dev, "couldn't register LED %s\n",
591 							led->cdev_led1b.name);
592 		goto failed_unregister_led1_B;
593 	}
594 
595 	led->cdev_led2r.name = "led2_R";
596 	led->cdev_led2r.brightness = LED_OFF;
597 	led->cdev_led2r.brightness_set_blocking = bd2802_set_led2r_brightness;
598 	led->cdev_led2r.blink_set = bd2802_set_led2r_blink;
599 
600 	ret = led_classdev_register(&led->client->dev, &led->cdev_led2r);
601 	if (ret < 0) {
602 		dev_err(&led->client->dev, "couldn't register LED %s\n",
603 							led->cdev_led2r.name);
604 		goto failed_unregister_led2_R;
605 	}
606 
607 	led->cdev_led2g.name = "led2_G";
608 	led->cdev_led2g.brightness = LED_OFF;
609 	led->cdev_led2g.brightness_set_blocking = bd2802_set_led2g_brightness;
610 	led->cdev_led2g.blink_set = bd2802_set_led2g_blink;
611 
612 	ret = led_classdev_register(&led->client->dev, &led->cdev_led2g);
613 	if (ret < 0) {
614 		dev_err(&led->client->dev, "couldn't register LED %s\n",
615 							led->cdev_led2g.name);
616 		goto failed_unregister_led2_G;
617 	}
618 
619 	led->cdev_led2b.name = "led2_B";
620 	led->cdev_led2b.brightness = LED_OFF;
621 	led->cdev_led2b.brightness_set_blocking = bd2802_set_led2b_brightness;
622 	led->cdev_led2b.blink_set = bd2802_set_led2b_blink;
623 	led->cdev_led2b.flags |= LED_CORE_SUSPENDRESUME;
624 
625 	ret = led_classdev_register(&led->client->dev, &led->cdev_led2b);
626 	if (ret < 0) {
627 		dev_err(&led->client->dev, "couldn't register LED %s\n",
628 							led->cdev_led2b.name);
629 		goto failed_unregister_led2_B;
630 	}
631 
632 	return 0;
633 
634 failed_unregister_led2_B:
635 	led_classdev_unregister(&led->cdev_led2g);
636 failed_unregister_led2_G:
637 	led_classdev_unregister(&led->cdev_led2r);
638 failed_unregister_led2_R:
639 	led_classdev_unregister(&led->cdev_led1b);
640 failed_unregister_led1_B:
641 	led_classdev_unregister(&led->cdev_led1g);
642 failed_unregister_led1_G:
643 	led_classdev_unregister(&led->cdev_led1r);
644 failed_unregister_led1_R:
645 
646 	return ret;
647 }
648 
649 static void bd2802_unregister_led_classdev(struct bd2802_led *led)
650 {
651 	led_classdev_unregister(&led->cdev_led2b);
652 	led_classdev_unregister(&led->cdev_led2g);
653 	led_classdev_unregister(&led->cdev_led2r);
654 	led_classdev_unregister(&led->cdev_led1b);
655 	led_classdev_unregister(&led->cdev_led1g);
656 	led_classdev_unregister(&led->cdev_led1r);
657 }
658 
659 static int bd2802_probe(struct i2c_client *client)
660 {
661 	struct bd2802_led *led;
662 	int ret, i;
663 
664 	led = devm_kzalloc(&client->dev, sizeof(struct bd2802_led), GFP_KERNEL);
665 	if (!led)
666 		return -ENOMEM;
667 
668 	led->client = client;
669 	i2c_set_clientdata(client, led);
670 
671 	/*
672 	 * Configure RESET GPIO (L: RESET, H: RESET cancel)
673 	 *
674 	 * We request the reset GPIO as OUT_LOW which means de-asserted,
675 	 * board files specifying this GPIO line in a machine descriptor
676 	 * table should take care to specify GPIO_ACTIVE_LOW for this line.
677 	 */
678 	led->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
679 	if (IS_ERR(led->reset))
680 		return PTR_ERR(led->reset);
681 
682 	/* Tacss = min 0.1ms */
683 	udelay(100);
684 
685 	/* Detect BD2802GU */
686 	ret = bd2802_write_byte(client, BD2802_REG_CLKSETUP, 0x00);
687 	if (ret < 0) {
688 		dev_err(&client->dev, "failed to detect device\n");
689 		return ret;
690 	} else
691 		dev_info(&client->dev, "return 0x%02x\n", ret);
692 
693 	/* To save the power, reset BD2802 after detecting */
694 	gpiod_set_value(led->reset, 1);
695 
696 	/* Default attributes */
697 	led->wave_pattern = BD2802_PATTERN_HALF;
698 	led->rgb_current = BD2802_CURRENT_032;
699 
700 	init_rwsem(&led->rwsem);
701 
702 	for (i = 0; i < ARRAY_SIZE(bd2802_attributes); i++) {
703 		ret = device_create_file(&led->client->dev,
704 						bd2802_attributes[i]);
705 		if (ret) {
706 			dev_err(&led->client->dev, "failed: sysfs file %s\n",
707 					bd2802_attributes[i]->attr.name);
708 			goto failed_unregister_dev_file;
709 		}
710 	}
711 
712 	ret = bd2802_register_led_classdev(led);
713 	if (ret < 0)
714 		goto failed_unregister_dev_file;
715 
716 	return 0;
717 
718 failed_unregister_dev_file:
719 	for (i--; i >= 0; i--)
720 		device_remove_file(&led->client->dev, bd2802_attributes[i]);
721 	return ret;
722 }
723 
724 static void bd2802_remove(struct i2c_client *client)
725 {
726 	struct bd2802_led *led = i2c_get_clientdata(client);
727 	int i;
728 
729 	gpiod_set_value(led->reset, 1);
730 	bd2802_unregister_led_classdev(led);
731 	if (led->adf_on)
732 		bd2802_disable_adv_conf(led);
733 	for (i = 0; i < ARRAY_SIZE(bd2802_attributes); i++)
734 		device_remove_file(&led->client->dev, bd2802_attributes[i]);
735 }
736 
737 #ifdef CONFIG_PM_SLEEP
738 static void bd2802_restore_state(struct bd2802_led *led)
739 {
740 	int i;
741 
742 	for (i = 0; i < LED_NUM; i++) {
743 		if (led->led[i].r)
744 			bd2802_turn_on(led, i, RED, led->led[i].r);
745 		if (led->led[i].g)
746 			bd2802_turn_on(led, i, GREEN, led->led[i].g);
747 		if (led->led[i].b)
748 			bd2802_turn_on(led, i, BLUE, led->led[i].b);
749 	}
750 }
751 
752 static int bd2802_suspend(struct device *dev)
753 {
754 	struct i2c_client *client = to_i2c_client(dev);
755 	struct bd2802_led *led = i2c_get_clientdata(client);
756 
757 	gpiod_set_value(led->reset, 1);
758 
759 	return 0;
760 }
761 
762 static int bd2802_resume(struct device *dev)
763 {
764 	struct i2c_client *client = to_i2c_client(dev);
765 	struct bd2802_led *led = i2c_get_clientdata(client);
766 
767 	if (!bd2802_is_all_off(led) || led->adf_on) {
768 		bd2802_reset_cancel(led);
769 		bd2802_restore_state(led);
770 	}
771 
772 	return 0;
773 }
774 #endif
775 
776 static SIMPLE_DEV_PM_OPS(bd2802_pm, bd2802_suspend, bd2802_resume);
777 
778 static const struct i2c_device_id bd2802_id[] = {
779 	{ "BD2802", 0 },
780 	{ }
781 };
782 MODULE_DEVICE_TABLE(i2c, bd2802_id);
783 
784 static struct i2c_driver bd2802_i2c_driver = {
785 	.driver	= {
786 		.name	= "BD2802",
787 		.pm	= &bd2802_pm,
788 	},
789 	.probe		= bd2802_probe,
790 	.remove		= bd2802_remove,
791 	.id_table	= bd2802_id,
792 };
793 
794 module_i2c_driver(bd2802_i2c_driver);
795 
796 MODULE_AUTHOR("Kim Kyuwon <q1.kim@samsung.com>");
797 MODULE_DESCRIPTION("BD2802 LED driver");
798 MODULE_LICENSE("GPL v2");
799