xref: /openbmc/linux/drivers/leds/leds-lp5523.c (revision 79f08d9e)
1 /*
2  * lp5523.c - LP5523 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/init.h>
29 #include <linux/leds.h>
30 #include <linux/module.h>
31 #include <linux/mutex.h>
32 #include <linux/of.h>
33 #include <linux/platform_data/leds-lp55xx.h>
34 #include <linux/slab.h>
35 
36 #include "leds-lp55xx-common.h"
37 
38 #define LP5523_PROGRAM_LENGTH		32
39 #define LP5523_MAX_LEDS			9
40 
41 /* Registers */
42 #define LP5523_REG_ENABLE		0x00
43 #define LP5523_REG_OP_MODE		0x01
44 #define LP5523_REG_ENABLE_LEDS_MSB	0x04
45 #define LP5523_REG_ENABLE_LEDS_LSB	0x05
46 #define LP5523_REG_LED_PWM_BASE		0x16
47 #define LP5523_REG_LED_CURRENT_BASE	0x26
48 #define LP5523_REG_CONFIG		0x36
49 #define LP5523_REG_STATUS		0x3A
50 #define LP5523_REG_RESET		0x3D
51 #define LP5523_REG_LED_TEST_CTRL	0x41
52 #define LP5523_REG_LED_TEST_ADC		0x42
53 #define LP5523_REG_CH1_PROG_START	0x4C
54 #define LP5523_REG_CH2_PROG_START	0x4D
55 #define LP5523_REG_CH3_PROG_START	0x4E
56 #define LP5523_REG_PROG_PAGE_SEL	0x4F
57 #define LP5523_REG_PROG_MEM		0x50
58 
59 /* Bit description in registers */
60 #define LP5523_ENABLE			0x40
61 #define LP5523_AUTO_INC			0x40
62 #define LP5523_PWR_SAVE			0x20
63 #define LP5523_PWM_PWR_SAVE		0x04
64 #define LP5523_CP_AUTO			0x18
65 #define LP5523_AUTO_CLK			0x02
66 
67 #define LP5523_EN_LEDTEST		0x80
68 #define LP5523_LEDTEST_DONE		0x80
69 #define LP5523_RESET			0xFF
70 #define LP5523_ADC_SHORTCIRC_LIM	80
71 #define LP5523_EXT_CLK_USED		0x08
72 #define LP5523_ENG_STATUS_MASK		0x07
73 
74 /* Memory Page Selection */
75 #define LP5523_PAGE_ENG1		0
76 #define LP5523_PAGE_ENG2		1
77 #define LP5523_PAGE_ENG3		2
78 #define LP5523_PAGE_MUX1		3
79 #define LP5523_PAGE_MUX2		4
80 #define LP5523_PAGE_MUX3		5
81 
82 /* Program Memory Operations */
83 #define LP5523_MODE_ENG1_M		0x30	/* Operation Mode Register */
84 #define LP5523_MODE_ENG2_M		0x0C
85 #define LP5523_MODE_ENG3_M		0x03
86 #define LP5523_LOAD_ENG1		0x10
87 #define LP5523_LOAD_ENG2		0x04
88 #define LP5523_LOAD_ENG3		0x01
89 
90 #define LP5523_ENG1_IS_LOADING(mode)	\
91 	((mode & LP5523_MODE_ENG1_M) == LP5523_LOAD_ENG1)
92 #define LP5523_ENG2_IS_LOADING(mode)	\
93 	((mode & LP5523_MODE_ENG2_M) == LP5523_LOAD_ENG2)
94 #define LP5523_ENG3_IS_LOADING(mode)	\
95 	((mode & LP5523_MODE_ENG3_M) == LP5523_LOAD_ENG3)
96 
97 #define LP5523_EXEC_ENG1_M		0x30	/* Enable Register */
98 #define LP5523_EXEC_ENG2_M		0x0C
99 #define LP5523_EXEC_ENG3_M		0x03
100 #define LP5523_EXEC_M			0x3F
101 #define LP5523_RUN_ENG1			0x20
102 #define LP5523_RUN_ENG2			0x08
103 #define LP5523_RUN_ENG3			0x02
104 
105 #define LED_ACTIVE(mux, led)		(!!(mux & (0x0001 << led)))
106 
107 enum lp5523_chip_id {
108 	LP5523,
109 	LP55231,
110 };
111 
112 static int lp5523_init_program_engine(struct lp55xx_chip *chip);
113 
114 static inline void lp5523_wait_opmode_done(void)
115 {
116 	usleep_range(1000, 2000);
117 }
118 
119 static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current)
120 {
121 	led->led_current = led_current;
122 	lp55xx_write(led->chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
123 		led_current);
124 }
125 
126 static int lp5523_post_init_device(struct lp55xx_chip *chip)
127 {
128 	int ret;
129 
130 	ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE);
131 	if (ret)
132 		return ret;
133 
134 	/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
135 	usleep_range(1000, 2000);
136 
137 	ret = lp55xx_write(chip, LP5523_REG_CONFIG,
138 			    LP5523_AUTO_INC | LP5523_PWR_SAVE |
139 			    LP5523_CP_AUTO | LP5523_AUTO_CLK |
140 			    LP5523_PWM_PWR_SAVE);
141 	if (ret)
142 		return ret;
143 
144 	/* turn on all leds */
145 	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
146 	if (ret)
147 		return ret;
148 
149 	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
150 	if (ret)
151 		return ret;
152 
153 	return lp5523_init_program_engine(chip);
154 }
155 
156 static void lp5523_load_engine(struct lp55xx_chip *chip)
157 {
158 	enum lp55xx_engine_index idx = chip->engine_idx;
159 	u8 mask[] = {
160 		[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
161 		[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
162 		[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
163 	};
164 
165 	u8 val[] = {
166 		[LP55XX_ENGINE_1] = LP5523_LOAD_ENG1,
167 		[LP55XX_ENGINE_2] = LP5523_LOAD_ENG2,
168 		[LP55XX_ENGINE_3] = LP5523_LOAD_ENG3,
169 	};
170 
171 	lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]);
172 
173 	lp5523_wait_opmode_done();
174 }
175 
176 static void lp5523_load_engine_and_select_page(struct lp55xx_chip *chip)
177 {
178 	enum lp55xx_engine_index idx = chip->engine_idx;
179 	u8 page_sel[] = {
180 		[LP55XX_ENGINE_1] = LP5523_PAGE_ENG1,
181 		[LP55XX_ENGINE_2] = LP5523_PAGE_ENG2,
182 		[LP55XX_ENGINE_3] = LP5523_PAGE_ENG3,
183 	};
184 
185 	lp5523_load_engine(chip);
186 
187 	lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]);
188 }
189 
190 static void lp5523_stop_engine(struct lp55xx_chip *chip)
191 {
192 	lp55xx_write(chip, LP5523_REG_OP_MODE, 0);
193 	lp5523_wait_opmode_done();
194 }
195 
196 static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
197 {
198 	int i;
199 
200 	for (i = 0; i < LP5523_MAX_LEDS; i++)
201 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
202 }
203 
204 static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
205 {
206 	int ret;
207 	u8 mode;
208 	u8 exec;
209 
210 	/* stop engine */
211 	if (!start) {
212 		lp5523_stop_engine(chip);
213 		lp5523_turn_off_channels(chip);
214 		return;
215 	}
216 
217 	/*
218 	 * To run the engine,
219 	 * operation mode and enable register should updated at the same time
220 	 */
221 
222 	ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
223 	if (ret)
224 		return;
225 
226 	ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
227 	if (ret)
228 		return;
229 
230 	/* change operation mode to RUN only when each engine is loading */
231 	if (LP5523_ENG1_IS_LOADING(mode)) {
232 		mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
233 		exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
234 	}
235 
236 	if (LP5523_ENG2_IS_LOADING(mode)) {
237 		mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
238 		exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
239 	}
240 
241 	if (LP5523_ENG3_IS_LOADING(mode)) {
242 		mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
243 		exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
244 	}
245 
246 	lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
247 	lp5523_wait_opmode_done();
248 
249 	lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
250 }
251 
252 static int lp5523_init_program_engine(struct lp55xx_chip *chip)
253 {
254 	int i;
255 	int j;
256 	int ret;
257 	u8 status;
258 	/* one pattern per engine setting LED MUX start and stop addresses */
259 	static const u8 pattern[][LP5523_PROGRAM_LENGTH] =  {
260 		{ 0x9c, 0x30, 0x9c, 0xb0, 0x9d, 0x80, 0xd8, 0x00, 0},
261 		{ 0x9c, 0x40, 0x9c, 0xc0, 0x9d, 0x80, 0xd8, 0x00, 0},
262 		{ 0x9c, 0x50, 0x9c, 0xd0, 0x9d, 0x80, 0xd8, 0x00, 0},
263 	};
264 
265 	/* hardcode 32 bytes of memory for each engine from program memory */
266 	ret = lp55xx_write(chip, LP5523_REG_CH1_PROG_START, 0x00);
267 	if (ret)
268 		return ret;
269 
270 	ret = lp55xx_write(chip, LP5523_REG_CH2_PROG_START, 0x10);
271 	if (ret)
272 		return ret;
273 
274 	ret = lp55xx_write(chip, LP5523_REG_CH3_PROG_START, 0x20);
275 	if (ret)
276 		return ret;
277 
278 	/* write LED MUX address space for each engine */
279 	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
280 		chip->engine_idx = i;
281 		lp5523_load_engine_and_select_page(chip);
282 
283 		for (j = 0; j < LP5523_PROGRAM_LENGTH; j++) {
284 			ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + j,
285 					pattern[i - 1][j]);
286 			if (ret)
287 				goto out;
288 		}
289 	}
290 
291 	lp5523_run_engine(chip, true);
292 
293 	/* Let the programs run for couple of ms and check the engine status */
294 	usleep_range(3000, 6000);
295 	lp55xx_read(chip, LP5523_REG_STATUS, &status);
296 	status &= LP5523_ENG_STATUS_MASK;
297 
298 	if (status != LP5523_ENG_STATUS_MASK) {
299 		dev_err(&chip->cl->dev,
300 			"cound not configure LED engine, status = 0x%.2x\n",
301 			status);
302 		ret = -1;
303 	}
304 
305 out:
306 	lp5523_stop_engine(chip);
307 	return ret;
308 }
309 
310 static int lp5523_update_program_memory(struct lp55xx_chip *chip,
311 					const u8 *data, size_t size)
312 {
313 	u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
314 	unsigned cmd;
315 	char c[3];
316 	int nrchars;
317 	int ret;
318 	int offset = 0;
319 	int i = 0;
320 
321 	while ((offset < size - 1) && (i < LP5523_PROGRAM_LENGTH)) {
322 		/* separate sscanfs because length is working only for %s */
323 		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
324 		if (ret != 1)
325 			goto err;
326 
327 		ret = sscanf(c, "%2x", &cmd);
328 		if (ret != 1)
329 			goto err;
330 
331 		pattern[i] = (u8)cmd;
332 		offset += nrchars;
333 		i++;
334 	}
335 
336 	/* Each instruction is 16bit long. Check that length is even */
337 	if (i % 2)
338 		goto err;
339 
340 	mutex_lock(&chip->lock);
341 
342 	for (i = 0; i < LP5523_PROGRAM_LENGTH; i++) {
343 		ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
344 		if (ret) {
345 			mutex_unlock(&chip->lock);
346 			return -EINVAL;
347 		}
348 	}
349 
350 	mutex_unlock(&chip->lock);
351 
352 	return size;
353 
354 err:
355 	dev_err(&chip->cl->dev, "wrong pattern format\n");
356 	return -EINVAL;
357 }
358 
359 static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
360 {
361 	const struct firmware *fw = chip->fw;
362 
363 	if (fw->size > LP5523_PROGRAM_LENGTH) {
364 		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
365 			fw->size);
366 		return;
367 	}
368 
369 	/*
370 	 * Program momery sequence
371 	 *  1) set engine mode to "LOAD"
372 	 *  2) write firmware data into program memory
373 	 */
374 
375 	lp5523_load_engine_and_select_page(chip);
376 	lp5523_update_program_memory(chip, fw->data, fw->size);
377 }
378 
379 static ssize_t show_engine_mode(struct device *dev,
380 				struct device_attribute *attr,
381 				char *buf, int nr)
382 {
383 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
384 	struct lp55xx_chip *chip = led->chip;
385 	enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
386 
387 	switch (mode) {
388 	case LP55XX_ENGINE_RUN:
389 		return sprintf(buf, "run\n");
390 	case LP55XX_ENGINE_LOAD:
391 		return sprintf(buf, "load\n");
392 	case LP55XX_ENGINE_DISABLED:
393 	default:
394 		return sprintf(buf, "disabled\n");
395 	}
396 }
397 show_mode(1)
398 show_mode(2)
399 show_mode(3)
400 
401 static ssize_t store_engine_mode(struct device *dev,
402 				 struct device_attribute *attr,
403 				 const char *buf, size_t len, int nr)
404 {
405 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
406 	struct lp55xx_chip *chip = led->chip;
407 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
408 
409 	mutex_lock(&chip->lock);
410 
411 	chip->engine_idx = nr;
412 
413 	if (!strncmp(buf, "run", 3)) {
414 		lp5523_run_engine(chip, true);
415 		engine->mode = LP55XX_ENGINE_RUN;
416 	} else if (!strncmp(buf, "load", 4)) {
417 		lp5523_stop_engine(chip);
418 		lp5523_load_engine(chip);
419 		engine->mode = LP55XX_ENGINE_LOAD;
420 	} else if (!strncmp(buf, "disabled", 8)) {
421 		lp5523_stop_engine(chip);
422 		engine->mode = LP55XX_ENGINE_DISABLED;
423 	}
424 
425 	mutex_unlock(&chip->lock);
426 
427 	return len;
428 }
429 store_mode(1)
430 store_mode(2)
431 store_mode(3)
432 
433 static int lp5523_mux_parse(const char *buf, u16 *mux, size_t len)
434 {
435 	u16 tmp_mux = 0;
436 	int i;
437 
438 	len = min_t(int, len, LP5523_MAX_LEDS);
439 
440 	for (i = 0; i < len; i++) {
441 		switch (buf[i]) {
442 		case '1':
443 			tmp_mux |= (1 << i);
444 			break;
445 		case '0':
446 			break;
447 		case '\n':
448 			i = len;
449 			break;
450 		default:
451 			return -1;
452 		}
453 	}
454 	*mux = tmp_mux;
455 
456 	return 0;
457 }
458 
459 static void lp5523_mux_to_array(u16 led_mux, char *array)
460 {
461 	int i, pos = 0;
462 	for (i = 0; i < LP5523_MAX_LEDS; i++)
463 		pos += sprintf(array + pos, "%x", LED_ACTIVE(led_mux, i));
464 
465 	array[pos] = '\0';
466 }
467 
468 static ssize_t show_engine_leds(struct device *dev,
469 			    struct device_attribute *attr,
470 			    char *buf, int nr)
471 {
472 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
473 	struct lp55xx_chip *chip = led->chip;
474 	char mux[LP5523_MAX_LEDS + 1];
475 
476 	lp5523_mux_to_array(chip->engines[nr - 1].led_mux, mux);
477 
478 	return sprintf(buf, "%s\n", mux);
479 }
480 show_leds(1)
481 show_leds(2)
482 show_leds(3)
483 
484 static int lp5523_load_mux(struct lp55xx_chip *chip, u16 mux, int nr)
485 {
486 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
487 	int ret;
488 	u8 mux_page[] = {
489 		[LP55XX_ENGINE_1] = LP5523_PAGE_MUX1,
490 		[LP55XX_ENGINE_2] = LP5523_PAGE_MUX2,
491 		[LP55XX_ENGINE_3] = LP5523_PAGE_MUX3,
492 	};
493 
494 	lp5523_load_engine(chip);
495 
496 	ret = lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, mux_page[nr]);
497 	if (ret)
498 		return ret;
499 
500 	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM , (u8)(mux >> 8));
501 	if (ret)
502 		return ret;
503 
504 	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + 1, (u8)(mux));
505 	if (ret)
506 		return ret;
507 
508 	engine->led_mux = mux;
509 	return 0;
510 }
511 
512 static ssize_t store_engine_leds(struct device *dev,
513 			     struct device_attribute *attr,
514 			     const char *buf, size_t len, int nr)
515 {
516 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
517 	struct lp55xx_chip *chip = led->chip;
518 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
519 	u16 mux = 0;
520 	ssize_t ret;
521 
522 	if (lp5523_mux_parse(buf, &mux, len))
523 		return -EINVAL;
524 
525 	mutex_lock(&chip->lock);
526 
527 	chip->engine_idx = nr;
528 	ret = -EINVAL;
529 
530 	if (engine->mode != LP55XX_ENGINE_LOAD)
531 		goto leave;
532 
533 	if (lp5523_load_mux(chip, mux, nr))
534 		goto leave;
535 
536 	ret = len;
537 leave:
538 	mutex_unlock(&chip->lock);
539 	return ret;
540 }
541 store_leds(1)
542 store_leds(2)
543 store_leds(3)
544 
545 static ssize_t store_engine_load(struct device *dev,
546 			     struct device_attribute *attr,
547 			     const char *buf, size_t len, int nr)
548 {
549 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
550 	struct lp55xx_chip *chip = led->chip;
551 
552 	mutex_lock(&chip->lock);
553 
554 	chip->engine_idx = nr;
555 	lp5523_load_engine_and_select_page(chip);
556 
557 	mutex_unlock(&chip->lock);
558 
559 	return lp5523_update_program_memory(chip, buf, len);
560 }
561 store_load(1)
562 store_load(2)
563 store_load(3)
564 
565 static ssize_t lp5523_selftest(struct device *dev,
566 			       struct device_attribute *attr,
567 			       char *buf)
568 {
569 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
570 	struct lp55xx_chip *chip = led->chip;
571 	struct lp55xx_platform_data *pdata = chip->pdata;
572 	int i, ret, pos = 0;
573 	u8 status, adc, vdd;
574 
575 	mutex_lock(&chip->lock);
576 
577 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
578 	if (ret < 0)
579 		goto fail;
580 
581 	/* Check that ext clock is really in use if requested */
582 	if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
583 		if  ((status & LP5523_EXT_CLK_USED) == 0)
584 			goto fail;
585 	}
586 
587 	/* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
588 	lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
589 	usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
590 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
591 	if (ret < 0)
592 		goto fail;
593 
594 	if (!(status & LP5523_LEDTEST_DONE))
595 		usleep_range(3000, 6000); /* Was not ready. Wait little bit */
596 
597 	ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
598 	if (ret < 0)
599 		goto fail;
600 
601 	vdd--;	/* There may be some fluctuation in measurement */
602 
603 	for (i = 0; i < LP5523_MAX_LEDS; i++) {
604 		/* Skip non-existing channels */
605 		if (pdata->led_config[i].led_current == 0)
606 			continue;
607 
608 		/* Set default current */
609 		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
610 			pdata->led_config[i].led_current);
611 
612 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff);
613 		/* let current stabilize 2 - 4ms before measurements start */
614 		usleep_range(2000, 4000);
615 		lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL,
616 			     LP5523_EN_LEDTEST | i);
617 		/* ADC conversion time is 2.7 ms typically */
618 		usleep_range(3000, 6000);
619 		ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
620 		if (ret < 0)
621 			goto fail;
622 
623 		if (!(status & LP5523_LEDTEST_DONE))
624 			usleep_range(3000, 6000);/* Was not ready. Wait. */
625 
626 		ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc);
627 		if (ret < 0)
628 			goto fail;
629 
630 		if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
631 			pos += sprintf(buf + pos, "LED %d FAIL\n", i);
632 
633 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00);
634 
635 		/* Restore current */
636 		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
637 			led->led_current);
638 		led++;
639 	}
640 	if (pos == 0)
641 		pos = sprintf(buf, "OK\n");
642 	goto release_lock;
643 fail:
644 	pos = sprintf(buf, "FAIL\n");
645 
646 release_lock:
647 	mutex_unlock(&chip->lock);
648 
649 	return pos;
650 }
651 
652 static void lp5523_led_brightness_work(struct work_struct *work)
653 {
654 	struct lp55xx_led *led = container_of(work, struct lp55xx_led,
655 					      brightness_work);
656 	struct lp55xx_chip *chip = led->chip;
657 
658 	mutex_lock(&chip->lock);
659 	lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
660 		     led->brightness);
661 	mutex_unlock(&chip->lock);
662 }
663 
664 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
665 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
666 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
667 static LP55XX_DEV_ATTR_RW(engine1_leds, show_engine1_leds, store_engine1_leds);
668 static LP55XX_DEV_ATTR_RW(engine2_leds, show_engine2_leds, store_engine2_leds);
669 static LP55XX_DEV_ATTR_RW(engine3_leds, show_engine3_leds, store_engine3_leds);
670 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
671 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
672 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
673 static LP55XX_DEV_ATTR_RO(selftest, lp5523_selftest);
674 
675 static struct attribute *lp5523_attributes[] = {
676 	&dev_attr_engine1_mode.attr,
677 	&dev_attr_engine2_mode.attr,
678 	&dev_attr_engine3_mode.attr,
679 	&dev_attr_engine1_load.attr,
680 	&dev_attr_engine2_load.attr,
681 	&dev_attr_engine3_load.attr,
682 	&dev_attr_engine1_leds.attr,
683 	&dev_attr_engine2_leds.attr,
684 	&dev_attr_engine3_leds.attr,
685 	&dev_attr_selftest.attr,
686 	NULL,
687 };
688 
689 static const struct attribute_group lp5523_group = {
690 	.attrs = lp5523_attributes,
691 };
692 
693 /* Chip specific configurations */
694 static struct lp55xx_device_config lp5523_cfg = {
695 	.reset = {
696 		.addr = LP5523_REG_RESET,
697 		.val  = LP5523_RESET,
698 	},
699 	.enable = {
700 		.addr = LP5523_REG_ENABLE,
701 		.val  = LP5523_ENABLE,
702 	},
703 	.max_channel  = LP5523_MAX_LEDS,
704 	.post_init_device   = lp5523_post_init_device,
705 	.brightness_work_fn = lp5523_led_brightness_work,
706 	.set_led_current    = lp5523_set_led_current,
707 	.firmware_cb        = lp5523_firmware_loaded,
708 	.run_engine         = lp5523_run_engine,
709 	.dev_attr_group     = &lp5523_group,
710 };
711 
712 static int lp5523_probe(struct i2c_client *client,
713 			const struct i2c_device_id *id)
714 {
715 	int ret;
716 	struct lp55xx_chip *chip;
717 	struct lp55xx_led *led;
718 	struct lp55xx_platform_data *pdata;
719 	struct device_node *np = client->dev.of_node;
720 
721 	if (!dev_get_platdata(&client->dev)) {
722 		if (np) {
723 			ret = lp55xx_of_populate_pdata(&client->dev, np);
724 			if (ret < 0)
725 				return ret;
726 		} else {
727 			dev_err(&client->dev, "no platform data\n");
728 			return -EINVAL;
729 		}
730 	}
731 	pdata = dev_get_platdata(&client->dev);
732 
733 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
734 	if (!chip)
735 		return -ENOMEM;
736 
737 	led = devm_kzalloc(&client->dev,
738 			sizeof(*led) * pdata->num_channels, GFP_KERNEL);
739 	if (!led)
740 		return -ENOMEM;
741 
742 	chip->cl = client;
743 	chip->pdata = pdata;
744 	chip->cfg = &lp5523_cfg;
745 
746 	mutex_init(&chip->lock);
747 
748 	i2c_set_clientdata(client, led);
749 
750 	ret = lp55xx_init_device(chip);
751 	if (ret)
752 		goto err_init;
753 
754 	dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
755 
756 	ret = lp55xx_register_leds(led, chip);
757 	if (ret)
758 		goto err_register_leds;
759 
760 	ret = lp55xx_register_sysfs(chip);
761 	if (ret) {
762 		dev_err(&client->dev, "registering sysfs failed\n");
763 		goto err_register_sysfs;
764 	}
765 
766 	return 0;
767 
768 err_register_sysfs:
769 	lp55xx_unregister_leds(led, chip);
770 err_register_leds:
771 	lp55xx_deinit_device(chip);
772 err_init:
773 	return ret;
774 }
775 
776 static int lp5523_remove(struct i2c_client *client)
777 {
778 	struct lp55xx_led *led = i2c_get_clientdata(client);
779 	struct lp55xx_chip *chip = led->chip;
780 
781 	lp5523_stop_engine(chip);
782 	lp55xx_unregister_sysfs(chip);
783 	lp55xx_unregister_leds(led, chip);
784 	lp55xx_deinit_device(chip);
785 
786 	return 0;
787 }
788 
789 static const struct i2c_device_id lp5523_id[] = {
790 	{ "lp5523",  LP5523 },
791 	{ "lp55231", LP55231 },
792 	{ }
793 };
794 
795 MODULE_DEVICE_TABLE(i2c, lp5523_id);
796 
797 #ifdef CONFIG_OF
798 static const struct of_device_id of_lp5523_leds_match[] = {
799 	{ .compatible = "national,lp5523", },
800 	{},
801 };
802 
803 MODULE_DEVICE_TABLE(of, of_lp5523_leds_match);
804 #endif
805 
806 static struct i2c_driver lp5523_driver = {
807 	.driver = {
808 		.name	= "lp5523x",
809 		.of_match_table = of_match_ptr(of_lp5523_leds_match),
810 	},
811 	.probe		= lp5523_probe,
812 	.remove		= lp5523_remove,
813 	.id_table	= lp5523_id,
814 };
815 
816 module_i2c_driver(lp5523_driver);
817 
818 MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
819 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
820 MODULE_DESCRIPTION("LP5523 LED engine");
821 MODULE_LICENSE("GPL");
822