xref: /linux/drivers/leds/leds-lp5523.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2  * lp5523.c - LP5523, LP55231 LED Driver
3  *
4  * Copyright (C) 2010 Nokia Corporation
5  * Copyright (C) 2012 Texas Instruments
6  *
7  * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
8  *          Milo(Woogyom) Kim <milo.kim@ti.com>
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License
12  * version 2 as published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
22  * 02110-1301 USA
23  */
24 
25 #include <linux/delay.h>
26 #include <linux/firmware.h>
27 #include <linux/i2c.h>
28 #include <linux/leds.h>
29 #include <linux/module.h>
30 #include <linux/mutex.h>
31 #include <linux/of.h>
32 #include <linux/platform_data/leds-lp55xx.h>
33 #include <linux/slab.h>
34 
35 #include "leds-lp55xx-common.h"
36 
37 #define LP5523_PROGRAM_LENGTH		32	/* bytes */
38 /* Memory is used like this:
39    0x00 engine 1 program
40    0x10 engine 2 program
41    0x20 engine 3 program
42    0x30 engine 1 muxing info
43    0x40 engine 2 muxing info
44    0x50 engine 3 muxing info
45 */
46 #define LP5523_MAX_LEDS			9
47 
48 /* Registers */
49 #define LP5523_REG_ENABLE		0x00
50 #define LP5523_REG_OP_MODE		0x01
51 #define LP5523_REG_ENABLE_LEDS_MSB	0x04
52 #define LP5523_REG_ENABLE_LEDS_LSB	0x05
53 #define LP5523_REG_LED_PWM_BASE		0x16
54 #define LP5523_REG_LED_CURRENT_BASE	0x26
55 #define LP5523_REG_CONFIG		0x36
56 #define LP5523_REG_STATUS		0x3A
57 #define LP5523_REG_RESET		0x3D
58 #define LP5523_REG_LED_TEST_CTRL	0x41
59 #define LP5523_REG_LED_TEST_ADC		0x42
60 #define LP5523_REG_CH1_PROG_START	0x4C
61 #define LP5523_REG_CH2_PROG_START	0x4D
62 #define LP5523_REG_CH3_PROG_START	0x4E
63 #define LP5523_REG_PROG_PAGE_SEL	0x4F
64 #define LP5523_REG_PROG_MEM		0x50
65 
66 /* Bit description in registers */
67 #define LP5523_ENABLE			0x40
68 #define LP5523_AUTO_INC			0x40
69 #define LP5523_PWR_SAVE			0x20
70 #define LP5523_PWM_PWR_SAVE		0x04
71 #define LP5523_CP_AUTO			0x18
72 #define LP5523_AUTO_CLK			0x02
73 
74 #define LP5523_EN_LEDTEST		0x80
75 #define LP5523_LEDTEST_DONE		0x80
76 #define LP5523_RESET			0xFF
77 #define LP5523_ADC_SHORTCIRC_LIM	80
78 #define LP5523_EXT_CLK_USED		0x08
79 #define LP5523_ENG_STATUS_MASK		0x07
80 
81 /* Memory Page Selection */
82 #define LP5523_PAGE_ENG1		0
83 #define LP5523_PAGE_ENG2		1
84 #define LP5523_PAGE_ENG3		2
85 #define LP5523_PAGE_MUX1		3
86 #define LP5523_PAGE_MUX2		4
87 #define LP5523_PAGE_MUX3		5
88 
89 /* Program Memory Operations */
90 #define LP5523_MODE_ENG1_M		0x30	/* Operation Mode Register */
91 #define LP5523_MODE_ENG2_M		0x0C
92 #define LP5523_MODE_ENG3_M		0x03
93 #define LP5523_LOAD_ENG1		0x10
94 #define LP5523_LOAD_ENG2		0x04
95 #define LP5523_LOAD_ENG3		0x01
96 
97 #define LP5523_ENG1_IS_LOADING(mode)	\
98 	((mode & LP5523_MODE_ENG1_M) == LP5523_LOAD_ENG1)
99 #define LP5523_ENG2_IS_LOADING(mode)	\
100 	((mode & LP5523_MODE_ENG2_M) == LP5523_LOAD_ENG2)
101 #define LP5523_ENG3_IS_LOADING(mode)	\
102 	((mode & LP5523_MODE_ENG3_M) == LP5523_LOAD_ENG3)
103 
104 #define LP5523_EXEC_ENG1_M		0x30	/* Enable Register */
105 #define LP5523_EXEC_ENG2_M		0x0C
106 #define LP5523_EXEC_ENG3_M		0x03
107 #define LP5523_EXEC_M			0x3F
108 #define LP5523_RUN_ENG1			0x20
109 #define LP5523_RUN_ENG2			0x08
110 #define LP5523_RUN_ENG3			0x02
111 
112 #define LED_ACTIVE(mux, led)		(!!(mux & (0x0001 << led)))
113 
114 enum lp5523_chip_id {
115 	LP5523,
116 	LP55231,
117 };
118 
119 static int lp5523_init_program_engine(struct lp55xx_chip *chip);
120 
121 static inline void lp5523_wait_opmode_done(void)
122 {
123 	usleep_range(1000, 2000);
124 }
125 
126 static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current)
127 {
128 	led->led_current = led_current;
129 	lp55xx_write(led->chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
130 		led_current);
131 }
132 
133 static int lp5523_post_init_device(struct lp55xx_chip *chip)
134 {
135 	int ret;
136 
137 	ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE);
138 	if (ret)
139 		return ret;
140 
141 	/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
142 	usleep_range(1000, 2000);
143 
144 	ret = lp55xx_write(chip, LP5523_REG_CONFIG,
145 			    LP5523_AUTO_INC | LP5523_PWR_SAVE |
146 			    LP5523_CP_AUTO | LP5523_AUTO_CLK |
147 			    LP5523_PWM_PWR_SAVE);
148 	if (ret)
149 		return ret;
150 
151 	/* turn on all leds */
152 	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
153 	if (ret)
154 		return ret;
155 
156 	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
157 	if (ret)
158 		return ret;
159 
160 	return lp5523_init_program_engine(chip);
161 }
162 
163 static void lp5523_load_engine(struct lp55xx_chip *chip)
164 {
165 	enum lp55xx_engine_index idx = chip->engine_idx;
166 	u8 mask[] = {
167 		[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
168 		[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
169 		[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
170 	};
171 
172 	u8 val[] = {
173 		[LP55XX_ENGINE_1] = LP5523_LOAD_ENG1,
174 		[LP55XX_ENGINE_2] = LP5523_LOAD_ENG2,
175 		[LP55XX_ENGINE_3] = LP5523_LOAD_ENG3,
176 	};
177 
178 	lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]);
179 
180 	lp5523_wait_opmode_done();
181 }
182 
183 static void lp5523_load_engine_and_select_page(struct lp55xx_chip *chip)
184 {
185 	enum lp55xx_engine_index idx = chip->engine_idx;
186 	u8 page_sel[] = {
187 		[LP55XX_ENGINE_1] = LP5523_PAGE_ENG1,
188 		[LP55XX_ENGINE_2] = LP5523_PAGE_ENG2,
189 		[LP55XX_ENGINE_3] = LP5523_PAGE_ENG3,
190 	};
191 
192 	lp5523_load_engine(chip);
193 
194 	lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]);
195 }
196 
197 static void lp5523_stop_all_engines(struct lp55xx_chip *chip)
198 {
199 	lp55xx_write(chip, LP5523_REG_OP_MODE, 0);
200 	lp5523_wait_opmode_done();
201 }
202 
203 static void lp5523_stop_engine(struct lp55xx_chip *chip)
204 {
205 	enum lp55xx_engine_index idx = chip->engine_idx;
206 	u8 mask[] = {
207 		[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
208 		[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
209 		[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
210 	};
211 
212 	lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], 0);
213 
214 	lp5523_wait_opmode_done();
215 }
216 
217 static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
218 {
219 	int i;
220 
221 	for (i = 0; i < LP5523_MAX_LEDS; i++)
222 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
223 }
224 
225 static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
226 {
227 	int ret;
228 	u8 mode;
229 	u8 exec;
230 
231 	/* stop engine */
232 	if (!start) {
233 		lp5523_stop_engine(chip);
234 		lp5523_turn_off_channels(chip);
235 		return;
236 	}
237 
238 	/*
239 	 * To run the engine,
240 	 * operation mode and enable register should updated at the same time
241 	 */
242 
243 	ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
244 	if (ret)
245 		return;
246 
247 	ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
248 	if (ret)
249 		return;
250 
251 	/* change operation mode to RUN only when each engine is loading */
252 	if (LP5523_ENG1_IS_LOADING(mode)) {
253 		mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
254 		exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
255 	}
256 
257 	if (LP5523_ENG2_IS_LOADING(mode)) {
258 		mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
259 		exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
260 	}
261 
262 	if (LP5523_ENG3_IS_LOADING(mode)) {
263 		mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
264 		exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
265 	}
266 
267 	lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
268 	lp5523_wait_opmode_done();
269 
270 	lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
271 }
272 
273 static int lp5523_init_program_engine(struct lp55xx_chip *chip)
274 {
275 	int i;
276 	int j;
277 	int ret;
278 	u8 status;
279 	/* one pattern per engine setting LED MUX start and stop addresses */
280 	static const u8 pattern[][LP5523_PROGRAM_LENGTH] =  {
281 		{ 0x9c, 0x30, 0x9c, 0xb0, 0x9d, 0x80, 0xd8, 0x00, 0},
282 		{ 0x9c, 0x40, 0x9c, 0xc0, 0x9d, 0x80, 0xd8, 0x00, 0},
283 		{ 0x9c, 0x50, 0x9c, 0xd0, 0x9d, 0x80, 0xd8, 0x00, 0},
284 	};
285 
286 	/* hardcode 32 bytes of memory for each engine from program memory */
287 	ret = lp55xx_write(chip, LP5523_REG_CH1_PROG_START, 0x00);
288 	if (ret)
289 		return ret;
290 
291 	ret = lp55xx_write(chip, LP5523_REG_CH2_PROG_START, 0x10);
292 	if (ret)
293 		return ret;
294 
295 	ret = lp55xx_write(chip, LP5523_REG_CH3_PROG_START, 0x20);
296 	if (ret)
297 		return ret;
298 
299 	/* write LED MUX address space for each engine */
300 	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
301 		chip->engine_idx = i;
302 		lp5523_load_engine_and_select_page(chip);
303 
304 		for (j = 0; j < LP5523_PROGRAM_LENGTH; j++) {
305 			ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + j,
306 					pattern[i - 1][j]);
307 			if (ret)
308 				goto out;
309 		}
310 	}
311 
312 	lp5523_run_engine(chip, true);
313 
314 	/* Let the programs run for couple of ms and check the engine status */
315 	usleep_range(3000, 6000);
316 	lp55xx_read(chip, LP5523_REG_STATUS, &status);
317 	status &= LP5523_ENG_STATUS_MASK;
318 
319 	if (status != LP5523_ENG_STATUS_MASK) {
320 		dev_err(&chip->cl->dev,
321 			"cound not configure LED engine, status = 0x%.2x\n",
322 			status);
323 		ret = -1;
324 	}
325 
326 out:
327 	lp5523_stop_all_engines(chip);
328 	return ret;
329 }
330 
331 static int lp5523_update_program_memory(struct lp55xx_chip *chip,
332 					const u8 *data, size_t size)
333 {
334 	u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
335 	unsigned cmd;
336 	char c[3];
337 	int nrchars;
338 	int ret;
339 	int offset = 0;
340 	int i = 0;
341 
342 	while ((offset < size - 1) && (i < LP5523_PROGRAM_LENGTH)) {
343 		/* separate sscanfs because length is working only for %s */
344 		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
345 		if (ret != 1)
346 			goto err;
347 
348 		ret = sscanf(c, "%2x", &cmd);
349 		if (ret != 1)
350 			goto err;
351 
352 		pattern[i] = (u8)cmd;
353 		offset += nrchars;
354 		i++;
355 	}
356 
357 	/* Each instruction is 16bit long. Check that length is even */
358 	if (i % 2)
359 		goto err;
360 
361 	for (i = 0; i < LP5523_PROGRAM_LENGTH; i++) {
362 		ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
363 		if (ret)
364 			return -EINVAL;
365 	}
366 
367 	return size;
368 
369 err:
370 	dev_err(&chip->cl->dev, "wrong pattern format\n");
371 	return -EINVAL;
372 }
373 
374 static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
375 {
376 	const struct firmware *fw = chip->fw;
377 
378 	if (fw->size > LP5523_PROGRAM_LENGTH) {
379 		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
380 			fw->size);
381 		return;
382 	}
383 
384 	/*
385 	 * Program momery sequence
386 	 *  1) set engine mode to "LOAD"
387 	 *  2) write firmware data into program memory
388 	 */
389 
390 	lp5523_load_engine_and_select_page(chip);
391 	lp5523_update_program_memory(chip, fw->data, fw->size);
392 }
393 
394 static ssize_t show_engine_mode(struct device *dev,
395 				struct device_attribute *attr,
396 				char *buf, int nr)
397 {
398 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
399 	struct lp55xx_chip *chip = led->chip;
400 	enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
401 
402 	switch (mode) {
403 	case LP55XX_ENGINE_RUN:
404 		return sprintf(buf, "run\n");
405 	case LP55XX_ENGINE_LOAD:
406 		return sprintf(buf, "load\n");
407 	case LP55XX_ENGINE_DISABLED:
408 	default:
409 		return sprintf(buf, "disabled\n");
410 	}
411 }
412 show_mode(1)
413 show_mode(2)
414 show_mode(3)
415 
416 static ssize_t store_engine_mode(struct device *dev,
417 				 struct device_attribute *attr,
418 				 const char *buf, size_t len, int nr)
419 {
420 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
421 	struct lp55xx_chip *chip = led->chip;
422 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
423 
424 	mutex_lock(&chip->lock);
425 
426 	chip->engine_idx = nr;
427 
428 	if (!strncmp(buf, "run", 3)) {
429 		lp5523_run_engine(chip, true);
430 		engine->mode = LP55XX_ENGINE_RUN;
431 	} else if (!strncmp(buf, "load", 4)) {
432 		lp5523_stop_engine(chip);
433 		lp5523_load_engine(chip);
434 		engine->mode = LP55XX_ENGINE_LOAD;
435 	} else if (!strncmp(buf, "disabled", 8)) {
436 		lp5523_stop_engine(chip);
437 		engine->mode = LP55XX_ENGINE_DISABLED;
438 	}
439 
440 	mutex_unlock(&chip->lock);
441 
442 	return len;
443 }
444 store_mode(1)
445 store_mode(2)
446 store_mode(3)
447 
448 static int lp5523_mux_parse(const char *buf, u16 *mux, size_t len)
449 {
450 	u16 tmp_mux = 0;
451 	int i;
452 
453 	len = min_t(int, len, LP5523_MAX_LEDS);
454 
455 	for (i = 0; i < len; i++) {
456 		switch (buf[i]) {
457 		case '1':
458 			tmp_mux |= (1 << i);
459 			break;
460 		case '0':
461 			break;
462 		case '\n':
463 			i = len;
464 			break;
465 		default:
466 			return -1;
467 		}
468 	}
469 	*mux = tmp_mux;
470 
471 	return 0;
472 }
473 
474 static void lp5523_mux_to_array(u16 led_mux, char *array)
475 {
476 	int i, pos = 0;
477 	for (i = 0; i < LP5523_MAX_LEDS; i++)
478 		pos += sprintf(array + pos, "%x", LED_ACTIVE(led_mux, i));
479 
480 	array[pos] = '\0';
481 }
482 
483 static ssize_t show_engine_leds(struct device *dev,
484 			    struct device_attribute *attr,
485 			    char *buf, int nr)
486 {
487 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
488 	struct lp55xx_chip *chip = led->chip;
489 	char mux[LP5523_MAX_LEDS + 1];
490 
491 	lp5523_mux_to_array(chip->engines[nr - 1].led_mux, mux);
492 
493 	return sprintf(buf, "%s\n", mux);
494 }
495 show_leds(1)
496 show_leds(2)
497 show_leds(3)
498 
499 static int lp5523_load_mux(struct lp55xx_chip *chip, u16 mux, int nr)
500 {
501 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
502 	int ret;
503 	u8 mux_page[] = {
504 		[LP55XX_ENGINE_1] = LP5523_PAGE_MUX1,
505 		[LP55XX_ENGINE_2] = LP5523_PAGE_MUX2,
506 		[LP55XX_ENGINE_3] = LP5523_PAGE_MUX3,
507 	};
508 
509 	lp5523_load_engine(chip);
510 
511 	ret = lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, mux_page[nr]);
512 	if (ret)
513 		return ret;
514 
515 	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM , (u8)(mux >> 8));
516 	if (ret)
517 		return ret;
518 
519 	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + 1, (u8)(mux));
520 	if (ret)
521 		return ret;
522 
523 	engine->led_mux = mux;
524 	return 0;
525 }
526 
527 static ssize_t store_engine_leds(struct device *dev,
528 			     struct device_attribute *attr,
529 			     const char *buf, size_t len, int nr)
530 {
531 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
532 	struct lp55xx_chip *chip = led->chip;
533 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
534 	u16 mux = 0;
535 	ssize_t ret;
536 
537 	if (lp5523_mux_parse(buf, &mux, len))
538 		return -EINVAL;
539 
540 	mutex_lock(&chip->lock);
541 
542 	chip->engine_idx = nr;
543 	ret = -EINVAL;
544 
545 	if (engine->mode != LP55XX_ENGINE_LOAD)
546 		goto leave;
547 
548 	if (lp5523_load_mux(chip, mux, nr))
549 		goto leave;
550 
551 	ret = len;
552 leave:
553 	mutex_unlock(&chip->lock);
554 	return ret;
555 }
556 store_leds(1)
557 store_leds(2)
558 store_leds(3)
559 
560 static ssize_t store_engine_load(struct device *dev,
561 			     struct device_attribute *attr,
562 			     const char *buf, size_t len, int nr)
563 {
564 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
565 	struct lp55xx_chip *chip = led->chip;
566 	int ret;
567 
568 	mutex_lock(&chip->lock);
569 
570 	chip->engine_idx = nr;
571 	lp5523_load_engine_and_select_page(chip);
572 	ret = lp5523_update_program_memory(chip, buf, len);
573 
574 	mutex_unlock(&chip->lock);
575 
576 	return ret;
577 }
578 store_load(1)
579 store_load(2)
580 store_load(3)
581 
582 static ssize_t lp5523_selftest(struct device *dev,
583 			       struct device_attribute *attr,
584 			       char *buf)
585 {
586 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
587 	struct lp55xx_chip *chip = led->chip;
588 	struct lp55xx_platform_data *pdata = chip->pdata;
589 	int i, ret, pos = 0;
590 	u8 status, adc, vdd;
591 
592 	mutex_lock(&chip->lock);
593 
594 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
595 	if (ret < 0)
596 		goto fail;
597 
598 	/* Check that ext clock is really in use if requested */
599 	if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
600 		if  ((status & LP5523_EXT_CLK_USED) == 0)
601 			goto fail;
602 	}
603 
604 	/* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
605 	lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
606 	usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
607 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
608 	if (ret < 0)
609 		goto fail;
610 
611 	if (!(status & LP5523_LEDTEST_DONE))
612 		usleep_range(3000, 6000); /* Was not ready. Wait little bit */
613 
614 	ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
615 	if (ret < 0)
616 		goto fail;
617 
618 	vdd--;	/* There may be some fluctuation in measurement */
619 
620 	for (i = 0; i < LP5523_MAX_LEDS; i++) {
621 		/* Skip non-existing channels */
622 		if (pdata->led_config[i].led_current == 0)
623 			continue;
624 
625 		/* Set default current */
626 		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
627 			pdata->led_config[i].led_current);
628 
629 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff);
630 		/* let current stabilize 2 - 4ms before measurements start */
631 		usleep_range(2000, 4000);
632 		lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL,
633 			     LP5523_EN_LEDTEST | i);
634 		/* ADC conversion time is 2.7 ms typically */
635 		usleep_range(3000, 6000);
636 		ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
637 		if (ret < 0)
638 			goto fail;
639 
640 		if (!(status & LP5523_LEDTEST_DONE))
641 			usleep_range(3000, 6000);/* Was not ready. Wait. */
642 
643 		ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc);
644 		if (ret < 0)
645 			goto fail;
646 
647 		if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
648 			pos += sprintf(buf + pos, "LED %d FAIL\n", i);
649 
650 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00);
651 
652 		/* Restore current */
653 		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
654 			led->led_current);
655 		led++;
656 	}
657 	if (pos == 0)
658 		pos = sprintf(buf, "OK\n");
659 	goto release_lock;
660 fail:
661 	pos = sprintf(buf, "FAIL\n");
662 
663 release_lock:
664 	mutex_unlock(&chip->lock);
665 
666 	return pos;
667 }
668 
669 static void lp5523_led_brightness_work(struct work_struct *work)
670 {
671 	struct lp55xx_led *led = container_of(work, struct lp55xx_led,
672 					      brightness_work);
673 	struct lp55xx_chip *chip = led->chip;
674 
675 	mutex_lock(&chip->lock);
676 	lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
677 		     led->brightness);
678 	mutex_unlock(&chip->lock);
679 }
680 
681 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
682 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
683 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
684 static LP55XX_DEV_ATTR_RW(engine1_leds, show_engine1_leds, store_engine1_leds);
685 static LP55XX_DEV_ATTR_RW(engine2_leds, show_engine2_leds, store_engine2_leds);
686 static LP55XX_DEV_ATTR_RW(engine3_leds, show_engine3_leds, store_engine3_leds);
687 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
688 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
689 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
690 static LP55XX_DEV_ATTR_RO(selftest, lp5523_selftest);
691 
692 static struct attribute *lp5523_attributes[] = {
693 	&dev_attr_engine1_mode.attr,
694 	&dev_attr_engine2_mode.attr,
695 	&dev_attr_engine3_mode.attr,
696 	&dev_attr_engine1_load.attr,
697 	&dev_attr_engine2_load.attr,
698 	&dev_attr_engine3_load.attr,
699 	&dev_attr_engine1_leds.attr,
700 	&dev_attr_engine2_leds.attr,
701 	&dev_attr_engine3_leds.attr,
702 	&dev_attr_selftest.attr,
703 	NULL,
704 };
705 
706 static const struct attribute_group lp5523_group = {
707 	.attrs = lp5523_attributes,
708 };
709 
710 /* Chip specific configurations */
711 static struct lp55xx_device_config lp5523_cfg = {
712 	.reset = {
713 		.addr = LP5523_REG_RESET,
714 		.val  = LP5523_RESET,
715 	},
716 	.enable = {
717 		.addr = LP5523_REG_ENABLE,
718 		.val  = LP5523_ENABLE,
719 	},
720 	.max_channel  = LP5523_MAX_LEDS,
721 	.post_init_device   = lp5523_post_init_device,
722 	.brightness_work_fn = lp5523_led_brightness_work,
723 	.set_led_current    = lp5523_set_led_current,
724 	.firmware_cb        = lp5523_firmware_loaded,
725 	.run_engine         = lp5523_run_engine,
726 	.dev_attr_group     = &lp5523_group,
727 };
728 
729 static int lp5523_probe(struct i2c_client *client,
730 			const struct i2c_device_id *id)
731 {
732 	int ret;
733 	struct lp55xx_chip *chip;
734 	struct lp55xx_led *led;
735 	struct lp55xx_platform_data *pdata;
736 	struct device_node *np = client->dev.of_node;
737 
738 	if (!dev_get_platdata(&client->dev)) {
739 		if (np) {
740 			ret = lp55xx_of_populate_pdata(&client->dev, np);
741 			if (ret < 0)
742 				return ret;
743 		} else {
744 			dev_err(&client->dev, "no platform data\n");
745 			return -EINVAL;
746 		}
747 	}
748 	pdata = dev_get_platdata(&client->dev);
749 
750 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
751 	if (!chip)
752 		return -ENOMEM;
753 
754 	led = devm_kzalloc(&client->dev,
755 			sizeof(*led) * pdata->num_channels, GFP_KERNEL);
756 	if (!led)
757 		return -ENOMEM;
758 
759 	chip->cl = client;
760 	chip->pdata = pdata;
761 	chip->cfg = &lp5523_cfg;
762 
763 	mutex_init(&chip->lock);
764 
765 	i2c_set_clientdata(client, led);
766 
767 	ret = lp55xx_init_device(chip);
768 	if (ret)
769 		goto err_init;
770 
771 	dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
772 
773 	ret = lp55xx_register_leds(led, chip);
774 	if (ret)
775 		goto err_register_leds;
776 
777 	ret = lp55xx_register_sysfs(chip);
778 	if (ret) {
779 		dev_err(&client->dev, "registering sysfs failed\n");
780 		goto err_register_sysfs;
781 	}
782 
783 	return 0;
784 
785 err_register_sysfs:
786 	lp55xx_unregister_leds(led, chip);
787 err_register_leds:
788 	lp55xx_deinit_device(chip);
789 err_init:
790 	return ret;
791 }
792 
793 static int lp5523_remove(struct i2c_client *client)
794 {
795 	struct lp55xx_led *led = i2c_get_clientdata(client);
796 	struct lp55xx_chip *chip = led->chip;
797 
798 	lp5523_stop_all_engines(chip);
799 	lp55xx_unregister_sysfs(chip);
800 	lp55xx_unregister_leds(led, chip);
801 	lp55xx_deinit_device(chip);
802 
803 	return 0;
804 }
805 
806 static const struct i2c_device_id lp5523_id[] = {
807 	{ "lp5523",  LP5523 },
808 	{ "lp55231", LP55231 },
809 	{ }
810 };
811 
812 MODULE_DEVICE_TABLE(i2c, lp5523_id);
813 
814 #ifdef CONFIG_OF
815 static const struct of_device_id of_lp5523_leds_match[] = {
816 	{ .compatible = "national,lp5523", },
817 	{ .compatible = "ti,lp55231", },
818 	{},
819 };
820 
821 MODULE_DEVICE_TABLE(of, of_lp5523_leds_match);
822 #endif
823 
824 static struct i2c_driver lp5523_driver = {
825 	.driver = {
826 		.name	= "lp5523x",
827 		.of_match_table = of_match_ptr(of_lp5523_leds_match),
828 	},
829 	.probe		= lp5523_probe,
830 	.remove		= lp5523_remove,
831 	.id_table	= lp5523_id,
832 };
833 
834 module_i2c_driver(lp5523_driver);
835 
836 MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
837 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
838 MODULE_DESCRIPTION("LP5523 LED engine");
839 MODULE_LICENSE("GPL");
840