xref: /linux/drivers/leds/leds-lm3533.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
1 /*
2  * leds-lm3533.c -- LM3533 LED driver
3  *
4  * Copyright (C) 2011-2012 Texas Instruments
5  *
6  * Author: Johan Hovold <jhovold@gmail.com>
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under  the terms of the GNU General  Public License as published by the
10  * Free Software Foundation;  either version 2 of the License, or (at your
11  * option) any later version.
12  */
13 
14 #include <linux/module.h>
15 #include <linux/leds.h>
16 #include <linux/mfd/core.h>
17 #include <linux/mutex.h>
18 #include <linux/platform_device.h>
19 #include <linux/slab.h>
20 #include <linux/workqueue.h>
21 
22 #include <linux/mfd/lm3533.h>
23 
24 
25 #define LM3533_LVCTRLBANK_MIN		2
26 #define LM3533_LVCTRLBANK_MAX		5
27 #define LM3533_LVCTRLBANK_COUNT		4
28 #define LM3533_RISEFALLTIME_MAX		7
29 #define LM3533_ALS_CHANNEL_LV_MIN	1
30 #define LM3533_ALS_CHANNEL_LV_MAX	2
31 
32 #define LM3533_REG_CTRLBANK_BCONF_BASE		0x1b
33 #define LM3533_REG_PATTERN_ENABLE		0x28
34 #define LM3533_REG_PATTERN_LOW_TIME_BASE	0x71
35 #define LM3533_REG_PATTERN_HIGH_TIME_BASE	0x72
36 #define LM3533_REG_PATTERN_RISETIME_BASE	0x74
37 #define LM3533_REG_PATTERN_FALLTIME_BASE	0x75
38 
39 #define LM3533_REG_PATTERN_STEP			0x10
40 
41 #define LM3533_REG_CTRLBANK_BCONF_MAPPING_MASK		0x04
42 #define LM3533_REG_CTRLBANK_BCONF_ALS_EN_MASK		0x02
43 #define LM3533_REG_CTRLBANK_BCONF_ALS_CHANNEL_MASK	0x01
44 
45 #define LM3533_LED_FLAG_PATTERN_ENABLE		1
46 
47 
48 struct lm3533_led {
49 	struct lm3533 *lm3533;
50 	struct lm3533_ctrlbank cb;
51 	struct led_classdev cdev;
52 	int id;
53 
54 	struct mutex mutex;
55 	unsigned long flags;
56 
57 	struct work_struct work;
58 	u8 new_brightness;
59 };
60 
61 
62 static inline struct lm3533_led *to_lm3533_led(struct led_classdev *cdev)
63 {
64 	return container_of(cdev, struct lm3533_led, cdev);
65 }
66 
67 static inline int lm3533_led_get_ctrlbank_id(struct lm3533_led *led)
68 {
69 	return led->id + 2;
70 }
71 
72 static inline u8 lm3533_led_get_lv_reg(struct lm3533_led *led, u8 base)
73 {
74 	return base + led->id;
75 }
76 
77 static inline u8 lm3533_led_get_pattern(struct lm3533_led *led)
78 {
79 	return led->id;
80 }
81 
82 static inline u8 lm3533_led_get_pattern_reg(struct lm3533_led *led,
83 								u8 base)
84 {
85 	return base + lm3533_led_get_pattern(led) * LM3533_REG_PATTERN_STEP;
86 }
87 
88 static int lm3533_led_pattern_enable(struct lm3533_led *led, int enable)
89 {
90 	u8 mask;
91 	u8 val;
92 	int pattern;
93 	int state;
94 	int ret = 0;
95 
96 	dev_dbg(led->cdev.dev, "%s - %d\n", __func__, enable);
97 
98 	mutex_lock(&led->mutex);
99 
100 	state = test_bit(LM3533_LED_FLAG_PATTERN_ENABLE, &led->flags);
101 	if ((enable && state) || (!enable && !state))
102 		goto out;
103 
104 	pattern = lm3533_led_get_pattern(led);
105 	mask = 1 << (2 * pattern);
106 
107 	if (enable)
108 		val = mask;
109 	else
110 		val = 0;
111 
112 	ret = lm3533_update(led->lm3533, LM3533_REG_PATTERN_ENABLE, val, mask);
113 	if (ret) {
114 		dev_err(led->cdev.dev, "failed to enable pattern %d (%d)\n",
115 							pattern, enable);
116 		goto out;
117 	}
118 
119 	__change_bit(LM3533_LED_FLAG_PATTERN_ENABLE, &led->flags);
120 out:
121 	mutex_unlock(&led->mutex);
122 
123 	return ret;
124 }
125 
126 static void lm3533_led_work(struct work_struct *work)
127 {
128 	struct lm3533_led *led = container_of(work, struct lm3533_led, work);
129 
130 	dev_dbg(led->cdev.dev, "%s - %u\n", __func__, led->new_brightness);
131 
132 	if (led->new_brightness == 0)
133 		lm3533_led_pattern_enable(led, 0);	/* disable blink */
134 
135 	lm3533_ctrlbank_set_brightness(&led->cb, led->new_brightness);
136 }
137 
138 static void lm3533_led_set(struct led_classdev *cdev,
139 						enum led_brightness value)
140 {
141 	struct lm3533_led *led = to_lm3533_led(cdev);
142 
143 	dev_dbg(led->cdev.dev, "%s - %d\n", __func__, value);
144 
145 	led->new_brightness = value;
146 	schedule_work(&led->work);
147 }
148 
149 static enum led_brightness lm3533_led_get(struct led_classdev *cdev)
150 {
151 	struct lm3533_led *led = to_lm3533_led(cdev);
152 	u8 val;
153 	int ret;
154 
155 	ret = lm3533_ctrlbank_get_brightness(&led->cb, &val);
156 	if (ret)
157 		return ret;
158 
159 	dev_dbg(led->cdev.dev, "%s - %u\n", __func__, val);
160 
161 	return val;
162 }
163 
164 /* Pattern generator defines (delays in us). */
165 #define LM3533_LED_DELAY1_VMIN	0x00
166 #define LM3533_LED_DELAY2_VMIN	0x3d
167 #define LM3533_LED_DELAY3_VMIN	0x80
168 
169 #define LM3533_LED_DELAY1_VMAX	(LM3533_LED_DELAY2_VMIN - 1)
170 #define LM3533_LED_DELAY2_VMAX	(LM3533_LED_DELAY3_VMIN - 1)
171 #define LM3533_LED_DELAY3_VMAX	0xff
172 
173 #define LM3533_LED_DELAY1_TMIN	16384U
174 #define LM3533_LED_DELAY2_TMIN	1130496U
175 #define LM3533_LED_DELAY3_TMIN	10305536U
176 
177 #define LM3533_LED_DELAY1_TMAX	999424U
178 #define LM3533_LED_DELAY2_TMAX	9781248U
179 #define LM3533_LED_DELAY3_TMAX	76890112U
180 
181 /* t_step = (t_max - t_min) / (v_max - v_min) */
182 #define LM3533_LED_DELAY1_TSTEP	16384
183 #define LM3533_LED_DELAY2_TSTEP	131072
184 #define LM3533_LED_DELAY3_TSTEP	524288
185 
186 /* Delay limits for hardware accelerated blinking (in ms). */
187 #define LM3533_LED_DELAY_ON_MAX \
188 	((LM3533_LED_DELAY2_TMAX + LM3533_LED_DELAY2_TSTEP / 2) / 1000)
189 #define LM3533_LED_DELAY_OFF_MAX \
190 	((LM3533_LED_DELAY3_TMAX + LM3533_LED_DELAY3_TSTEP / 2) / 1000)
191 
192 /*
193  * Returns linear map of *t from [t_min,t_max] to [v_min,v_max] with a step
194  * size of t_step, where
195  *
196  *	t_step = (t_max - t_min) / (v_max - v_min)
197  *
198  * and updates *t to reflect the mapped value.
199  */
200 static u8 time_to_val(unsigned *t, unsigned t_min, unsigned t_step,
201 							u8 v_min, u8 v_max)
202 {
203 	unsigned val;
204 
205 	val = (*t + t_step / 2 - t_min) / t_step + v_min;
206 
207 	*t = t_step * (val - v_min) + t_min;
208 
209 	return (u8)val;
210 }
211 
212 /*
213  * Returns time code corresponding to *delay (in ms) and updates *delay to
214  * reflect actual hardware delay.
215  *
216  * Hardware supports 256 discrete delay times, divided into three groups with
217  * the following ranges and step-sizes:
218  *
219  *	[   16,   999]	[0x00, 0x3e]	step  16 ms
220  *	[ 1130,  9781]	[0x3d, 0x7f]	step 131 ms
221  *	[10306, 76890]	[0x80, 0xff]	step 524 ms
222  *
223  * Note that delay group 3 is only available for delay_off.
224  */
225 static u8 lm3533_led_get_hw_delay(unsigned *delay)
226 {
227 	unsigned t;
228 	u8 val;
229 
230 	t = *delay * 1000;
231 
232 	if (t >= (LM3533_LED_DELAY2_TMAX + LM3533_LED_DELAY3_TMIN) / 2) {
233 		t = clamp(t, LM3533_LED_DELAY3_TMIN, LM3533_LED_DELAY3_TMAX);
234 		val = time_to_val(&t,	LM3533_LED_DELAY3_TMIN,
235 					LM3533_LED_DELAY3_TSTEP,
236 					LM3533_LED_DELAY3_VMIN,
237 					LM3533_LED_DELAY3_VMAX);
238 	} else if (t >= (LM3533_LED_DELAY1_TMAX + LM3533_LED_DELAY2_TMIN) / 2) {
239 		t = clamp(t, LM3533_LED_DELAY2_TMIN, LM3533_LED_DELAY2_TMAX);
240 		val = time_to_val(&t,	LM3533_LED_DELAY2_TMIN,
241 					LM3533_LED_DELAY2_TSTEP,
242 					LM3533_LED_DELAY2_VMIN,
243 					LM3533_LED_DELAY2_VMAX);
244 	} else {
245 		t = clamp(t, LM3533_LED_DELAY1_TMIN, LM3533_LED_DELAY1_TMAX);
246 		val = time_to_val(&t,	LM3533_LED_DELAY1_TMIN,
247 					LM3533_LED_DELAY1_TSTEP,
248 					LM3533_LED_DELAY1_VMIN,
249 					LM3533_LED_DELAY1_VMAX);
250 	}
251 
252 	*delay = (t + 500) / 1000;
253 
254 	return val;
255 }
256 
257 /*
258  * Set delay register base to *delay (in ms) and update *delay to reflect
259  * actual hardware delay used.
260  */
261 static u8 lm3533_led_delay_set(struct lm3533_led *led, u8 base,
262 							unsigned long *delay)
263 {
264 	unsigned t;
265 	u8 val;
266 	u8 reg;
267 	int ret;
268 
269 	t = (unsigned)*delay;
270 
271 	/* Delay group 3 is only available for low time (delay off). */
272 	if (base != LM3533_REG_PATTERN_LOW_TIME_BASE)
273 		t = min(t, LM3533_LED_DELAY2_TMAX / 1000);
274 
275 	val = lm3533_led_get_hw_delay(&t);
276 
277 	dev_dbg(led->cdev.dev, "%s - %lu: %u (0x%02x)\n", __func__,
278 							*delay, t, val);
279 	reg = lm3533_led_get_pattern_reg(led, base);
280 	ret = lm3533_write(led->lm3533, reg, val);
281 	if (ret)
282 		dev_err(led->cdev.dev, "failed to set delay (%02x)\n", reg);
283 
284 	*delay = t;
285 
286 	return ret;
287 }
288 
289 static int lm3533_led_delay_on_set(struct lm3533_led *led, unsigned long *t)
290 {
291 	return lm3533_led_delay_set(led, LM3533_REG_PATTERN_HIGH_TIME_BASE, t);
292 }
293 
294 static int lm3533_led_delay_off_set(struct lm3533_led *led, unsigned long *t)
295 {
296 	return lm3533_led_delay_set(led, LM3533_REG_PATTERN_LOW_TIME_BASE, t);
297 }
298 
299 static int lm3533_led_blink_set(struct led_classdev *cdev,
300 				unsigned long *delay_on,
301 				unsigned long *delay_off)
302 {
303 	struct lm3533_led *led = to_lm3533_led(cdev);
304 	int ret;
305 
306 	dev_dbg(led->cdev.dev, "%s - on = %lu, off = %lu\n", __func__,
307 							*delay_on, *delay_off);
308 
309 	if (*delay_on > LM3533_LED_DELAY_ON_MAX ||
310 					*delay_off > LM3533_LED_DELAY_OFF_MAX)
311 		return -EINVAL;
312 
313 	if (*delay_on == 0 && *delay_off == 0) {
314 		*delay_on = 500;
315 		*delay_off = 500;
316 	}
317 
318 	ret = lm3533_led_delay_on_set(led, delay_on);
319 	if (ret)
320 		return ret;
321 
322 	ret = lm3533_led_delay_off_set(led, delay_off);
323 	if (ret)
324 		return ret;
325 
326 	return lm3533_led_pattern_enable(led, 1);
327 }
328 
329 static ssize_t show_id(struct device *dev,
330 				struct device_attribute *attr, char *buf)
331 {
332 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
333 	struct lm3533_led *led = to_lm3533_led(led_cdev);
334 
335 	return scnprintf(buf, PAGE_SIZE, "%d\n", led->id);
336 }
337 
338 /*
339  * Pattern generator rise/fall times:
340  *
341  *   0 - 2048 us (default)
342  *   1 - 262 ms
343  *   2 - 524 ms
344  *   3 - 1.049 s
345  *   4 - 2.097 s
346  *   5 - 4.194 s
347  *   6 - 8.389 s
348  *   7 - 16.78 s
349  */
350 static ssize_t show_risefalltime(struct device *dev,
351 					struct device_attribute *attr,
352 					char *buf, u8 base)
353 {
354 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
355 	struct lm3533_led *led = to_lm3533_led(led_cdev);
356 	ssize_t ret;
357 	u8 reg;
358 	u8 val;
359 
360 	reg = lm3533_led_get_pattern_reg(led, base);
361 	ret = lm3533_read(led->lm3533, reg, &val);
362 	if (ret)
363 		return ret;
364 
365 	return scnprintf(buf, PAGE_SIZE, "%x\n", val);
366 }
367 
368 static ssize_t show_risetime(struct device *dev,
369 				struct device_attribute *attr, char *buf)
370 {
371 	return show_risefalltime(dev, attr, buf,
372 					LM3533_REG_PATTERN_RISETIME_BASE);
373 }
374 
375 static ssize_t show_falltime(struct device *dev,
376 				struct device_attribute *attr, char *buf)
377 {
378 	return show_risefalltime(dev, attr, buf,
379 					LM3533_REG_PATTERN_FALLTIME_BASE);
380 }
381 
382 static ssize_t store_risefalltime(struct device *dev,
383 					struct device_attribute *attr,
384 					const char *buf, size_t len, u8 base)
385 {
386 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
387 	struct lm3533_led *led = to_lm3533_led(led_cdev);
388 	u8 val;
389 	u8 reg;
390 	int ret;
391 
392 	if (kstrtou8(buf, 0, &val) || val > LM3533_RISEFALLTIME_MAX)
393 		return -EINVAL;
394 
395 	reg = lm3533_led_get_pattern_reg(led, base);
396 	ret = lm3533_write(led->lm3533, reg, val);
397 	if (ret)
398 		return ret;
399 
400 	return len;
401 }
402 
403 static ssize_t store_risetime(struct device *dev,
404 					struct device_attribute *attr,
405 					const char *buf, size_t len)
406 {
407 	return store_risefalltime(dev, attr, buf, len,
408 					LM3533_REG_PATTERN_RISETIME_BASE);
409 }
410 
411 static ssize_t store_falltime(struct device *dev,
412 					struct device_attribute *attr,
413 					const char *buf, size_t len)
414 {
415 	return store_risefalltime(dev, attr, buf, len,
416 					LM3533_REG_PATTERN_FALLTIME_BASE);
417 }
418 
419 static ssize_t show_als_channel(struct device *dev,
420 				struct device_attribute *attr, char *buf)
421 {
422 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
423 	struct lm3533_led *led = to_lm3533_led(led_cdev);
424 	unsigned channel;
425 	u8 reg;
426 	u8 val;
427 	int ret;
428 
429 	reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);
430 	ret = lm3533_read(led->lm3533, reg, &val);
431 	if (ret)
432 		return ret;
433 
434 	channel = (val & LM3533_REG_CTRLBANK_BCONF_ALS_CHANNEL_MASK) + 1;
435 
436 	return scnprintf(buf, PAGE_SIZE, "%u\n", channel);
437 }
438 
439 static ssize_t store_als_channel(struct device *dev,
440 					struct device_attribute *attr,
441 					const char *buf, size_t len)
442 {
443 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
444 	struct lm3533_led *led = to_lm3533_led(led_cdev);
445 	unsigned channel;
446 	u8 reg;
447 	u8 val;
448 	u8 mask;
449 	int ret;
450 
451 	if (kstrtouint(buf, 0, &channel))
452 		return -EINVAL;
453 
454 	if (channel < LM3533_ALS_CHANNEL_LV_MIN ||
455 					channel > LM3533_ALS_CHANNEL_LV_MAX)
456 		return -EINVAL;
457 
458 	reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);
459 	mask = LM3533_REG_CTRLBANK_BCONF_ALS_CHANNEL_MASK;
460 	val = channel - 1;
461 
462 	ret = lm3533_update(led->lm3533, reg, val, mask);
463 	if (ret)
464 		return ret;
465 
466 	return len;
467 }
468 
469 static ssize_t show_als_en(struct device *dev,
470 				struct device_attribute *attr, char *buf)
471 {
472 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
473 	struct lm3533_led *led = to_lm3533_led(led_cdev);
474 	bool enable;
475 	u8 reg;
476 	u8 val;
477 	int ret;
478 
479 	reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);
480 	ret = lm3533_read(led->lm3533, reg, &val);
481 	if (ret)
482 		return ret;
483 
484 	enable = val & LM3533_REG_CTRLBANK_BCONF_ALS_EN_MASK;
485 
486 	return scnprintf(buf, PAGE_SIZE, "%d\n", enable);
487 }
488 
489 static ssize_t store_als_en(struct device *dev,
490 					struct device_attribute *attr,
491 					const char *buf, size_t len)
492 {
493 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
494 	struct lm3533_led *led = to_lm3533_led(led_cdev);
495 	unsigned enable;
496 	u8 reg;
497 	u8 mask;
498 	u8 val;
499 	int ret;
500 
501 	if (kstrtouint(buf, 0, &enable))
502 		return -EINVAL;
503 
504 	reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);
505 	mask = LM3533_REG_CTRLBANK_BCONF_ALS_EN_MASK;
506 
507 	if (enable)
508 		val = mask;
509 	else
510 		val = 0;
511 
512 	ret = lm3533_update(led->lm3533, reg, val, mask);
513 	if (ret)
514 		return ret;
515 
516 	return len;
517 }
518 
519 static ssize_t show_linear(struct device *dev,
520 				struct device_attribute *attr, char *buf)
521 {
522 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
523 	struct lm3533_led *led = to_lm3533_led(led_cdev);
524 	u8 reg;
525 	u8 val;
526 	int linear;
527 	int ret;
528 
529 	reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);
530 	ret = lm3533_read(led->lm3533, reg, &val);
531 	if (ret)
532 		return ret;
533 
534 	if (val & LM3533_REG_CTRLBANK_BCONF_MAPPING_MASK)
535 		linear = 1;
536 	else
537 		linear = 0;
538 
539 	return scnprintf(buf, PAGE_SIZE, "%x\n", linear);
540 }
541 
542 static ssize_t store_linear(struct device *dev,
543 					struct device_attribute *attr,
544 					const char *buf, size_t len)
545 {
546 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
547 	struct lm3533_led *led = to_lm3533_led(led_cdev);
548 	unsigned long linear;
549 	u8 reg;
550 	u8 mask;
551 	u8 val;
552 	int ret;
553 
554 	if (kstrtoul(buf, 0, &linear))
555 		return -EINVAL;
556 
557 	reg = lm3533_led_get_lv_reg(led, LM3533_REG_CTRLBANK_BCONF_BASE);
558 	mask = LM3533_REG_CTRLBANK_BCONF_MAPPING_MASK;
559 
560 	if (linear)
561 		val = mask;
562 	else
563 		val = 0;
564 
565 	ret = lm3533_update(led->lm3533, reg, val, mask);
566 	if (ret)
567 		return ret;
568 
569 	return len;
570 }
571 
572 static ssize_t show_pwm(struct device *dev,
573 					struct device_attribute *attr,
574 					char *buf)
575 {
576 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
577 	struct lm3533_led *led = to_lm3533_led(led_cdev);
578 	u8 val;
579 	int ret;
580 
581 	ret = lm3533_ctrlbank_get_pwm(&led->cb, &val);
582 	if (ret)
583 		return ret;
584 
585 	return scnprintf(buf, PAGE_SIZE, "%u\n", val);
586 }
587 
588 static ssize_t store_pwm(struct device *dev,
589 					struct device_attribute *attr,
590 					const char *buf, size_t len)
591 {
592 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
593 	struct lm3533_led *led = to_lm3533_led(led_cdev);
594 	u8 val;
595 	int ret;
596 
597 	if (kstrtou8(buf, 0, &val))
598 		return -EINVAL;
599 
600 	ret = lm3533_ctrlbank_set_pwm(&led->cb, val);
601 	if (ret)
602 		return ret;
603 
604 	return len;
605 }
606 
607 static LM3533_ATTR_RW(als_channel);
608 static LM3533_ATTR_RW(als_en);
609 static LM3533_ATTR_RW(falltime);
610 static LM3533_ATTR_RO(id);
611 static LM3533_ATTR_RW(linear);
612 static LM3533_ATTR_RW(pwm);
613 static LM3533_ATTR_RW(risetime);
614 
615 static struct attribute *lm3533_led_attributes[] = {
616 	&dev_attr_als_channel.attr,
617 	&dev_attr_als_en.attr,
618 	&dev_attr_falltime.attr,
619 	&dev_attr_id.attr,
620 	&dev_attr_linear.attr,
621 	&dev_attr_pwm.attr,
622 	&dev_attr_risetime.attr,
623 	NULL,
624 };
625 
626 static umode_t lm3533_led_attr_is_visible(struct kobject *kobj,
627 					     struct attribute *attr, int n)
628 {
629 	struct device *dev = container_of(kobj, struct device, kobj);
630 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
631 	struct lm3533_led *led = to_lm3533_led(led_cdev);
632 	umode_t mode = attr->mode;
633 
634 	if (attr == &dev_attr_als_channel.attr ||
635 					attr == &dev_attr_als_en.attr) {
636 		if (!led->lm3533->have_als)
637 			mode = 0;
638 	}
639 
640 	return mode;
641 };
642 
643 static struct attribute_group lm3533_led_attribute_group = {
644 	.is_visible	= lm3533_led_attr_is_visible,
645 	.attrs		= lm3533_led_attributes
646 };
647 
648 static const struct attribute_group *lm3533_led_attribute_groups[] = {
649 	&lm3533_led_attribute_group,
650 	NULL
651 };
652 
653 static int lm3533_led_setup(struct lm3533_led *led,
654 					struct lm3533_led_platform_data *pdata)
655 {
656 	int ret;
657 
658 	ret = lm3533_ctrlbank_set_max_current(&led->cb, pdata->max_current);
659 	if (ret)
660 		return ret;
661 
662 	return lm3533_ctrlbank_set_pwm(&led->cb, pdata->pwm);
663 }
664 
665 static int lm3533_led_probe(struct platform_device *pdev)
666 {
667 	struct lm3533 *lm3533;
668 	struct lm3533_led_platform_data *pdata;
669 	struct lm3533_led *led;
670 	int ret;
671 
672 	dev_dbg(&pdev->dev, "%s\n", __func__);
673 
674 	lm3533 = dev_get_drvdata(pdev->dev.parent);
675 	if (!lm3533)
676 		return -EINVAL;
677 
678 	pdata = dev_get_platdata(&pdev->dev);
679 	if (!pdata) {
680 		dev_err(&pdev->dev, "no platform data\n");
681 		return -EINVAL;
682 	}
683 
684 	if (pdev->id < 0 || pdev->id >= LM3533_LVCTRLBANK_COUNT) {
685 		dev_err(&pdev->dev, "illegal LED id %d\n", pdev->id);
686 		return -EINVAL;
687 	}
688 
689 	led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
690 	if (!led)
691 		return -ENOMEM;
692 
693 	led->lm3533 = lm3533;
694 	led->cdev.name = pdata->name;
695 	led->cdev.default_trigger = pdata->default_trigger;
696 	led->cdev.brightness_set = lm3533_led_set;
697 	led->cdev.brightness_get = lm3533_led_get;
698 	led->cdev.blink_set = lm3533_led_blink_set;
699 	led->cdev.brightness = LED_OFF;
700 	led->cdev.groups = lm3533_led_attribute_groups,
701 	led->id = pdev->id;
702 
703 	mutex_init(&led->mutex);
704 	INIT_WORK(&led->work, lm3533_led_work);
705 
706 	/* The class framework makes a callback to get brightness during
707 	 * registration so use parent device (for error reporting) until
708 	 * registered.
709 	 */
710 	led->cb.lm3533 = lm3533;
711 	led->cb.id = lm3533_led_get_ctrlbank_id(led);
712 	led->cb.dev = lm3533->dev;
713 
714 	platform_set_drvdata(pdev, led);
715 
716 	ret = led_classdev_register(pdev->dev.parent, &led->cdev);
717 	if (ret) {
718 		dev_err(&pdev->dev, "failed to register LED %d\n", pdev->id);
719 		return ret;
720 	}
721 
722 	led->cb.dev = led->cdev.dev;
723 
724 	ret = lm3533_led_setup(led, pdata);
725 	if (ret)
726 		goto err_unregister;
727 
728 	ret = lm3533_ctrlbank_enable(&led->cb);
729 	if (ret)
730 		goto err_unregister;
731 
732 	return 0;
733 
734 err_unregister:
735 	led_classdev_unregister(&led->cdev);
736 	flush_work(&led->work);
737 
738 	return ret;
739 }
740 
741 static int lm3533_led_remove(struct platform_device *pdev)
742 {
743 	struct lm3533_led *led = platform_get_drvdata(pdev);
744 
745 	dev_dbg(&pdev->dev, "%s\n", __func__);
746 
747 	lm3533_ctrlbank_disable(&led->cb);
748 	led_classdev_unregister(&led->cdev);
749 	flush_work(&led->work);
750 
751 	return 0;
752 }
753 
754 static void lm3533_led_shutdown(struct platform_device *pdev)
755 {
756 
757 	struct lm3533_led *led = platform_get_drvdata(pdev);
758 
759 	dev_dbg(&pdev->dev, "%s\n", __func__);
760 
761 	lm3533_ctrlbank_disable(&led->cb);
762 	lm3533_led_set(&led->cdev, LED_OFF);		/* disable blink */
763 	flush_work(&led->work);
764 }
765 
766 static struct platform_driver lm3533_led_driver = {
767 	.driver = {
768 		.name = "lm3533-leds",
769 	},
770 	.probe		= lm3533_led_probe,
771 	.remove		= lm3533_led_remove,
772 	.shutdown	= lm3533_led_shutdown,
773 };
774 module_platform_driver(lm3533_led_driver);
775 
776 MODULE_AUTHOR("Johan Hovold <jhovold@gmail.com>");
777 MODULE_DESCRIPTION("LM3533 LED driver");
778 MODULE_LICENSE("GPL");
779 MODULE_ALIAS("platform:lm3533-leds");
780