xref: /openbmc/linux/drivers/leds/leds-lp5523.c (revision 5bd8e16d)
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/platform_data/leds-lp55xx.h>
33 #include <linux/slab.h>
34 
35 #include "leds-lp55xx-common.h"
36 
37 #define LP5523_PROGRAM_LENGTH		32
38 #define LP5523_MAX_LEDS			9
39 
40 /* Registers */
41 #define LP5523_REG_ENABLE		0x00
42 #define LP5523_REG_OP_MODE		0x01
43 #define LP5523_REG_ENABLE_LEDS_MSB	0x04
44 #define LP5523_REG_ENABLE_LEDS_LSB	0x05
45 #define LP5523_REG_LED_PWM_BASE		0x16
46 #define LP5523_REG_LED_CURRENT_BASE	0x26
47 #define LP5523_REG_CONFIG		0x36
48 #define LP5523_REG_STATUS		0x3A
49 #define LP5523_REG_RESET		0x3D
50 #define LP5523_REG_LED_TEST_CTRL	0x41
51 #define LP5523_REG_LED_TEST_ADC		0x42
52 #define LP5523_REG_CH1_PROG_START	0x4C
53 #define LP5523_REG_CH2_PROG_START	0x4D
54 #define LP5523_REG_CH3_PROG_START	0x4E
55 #define LP5523_REG_PROG_PAGE_SEL	0x4F
56 #define LP5523_REG_PROG_MEM		0x50
57 
58 /* Bit description in registers */
59 #define LP5523_ENABLE			0x40
60 #define LP5523_AUTO_INC			0x40
61 #define LP5523_PWR_SAVE			0x20
62 #define LP5523_PWM_PWR_SAVE		0x04
63 #define LP5523_CP_AUTO			0x18
64 #define LP5523_AUTO_CLK			0x02
65 
66 #define LP5523_EN_LEDTEST		0x80
67 #define LP5523_LEDTEST_DONE		0x80
68 #define LP5523_RESET			0xFF
69 #define LP5523_ADC_SHORTCIRC_LIM	80
70 #define LP5523_EXT_CLK_USED		0x08
71 #define LP5523_ENG_STATUS_MASK		0x07
72 
73 /* Memory Page Selection */
74 #define LP5523_PAGE_ENG1		0
75 #define LP5523_PAGE_ENG2		1
76 #define LP5523_PAGE_ENG3		2
77 #define LP5523_PAGE_MUX1		3
78 #define LP5523_PAGE_MUX2		4
79 #define LP5523_PAGE_MUX3		5
80 
81 /* Program Memory Operations */
82 #define LP5523_MODE_ENG1_M		0x30	/* Operation Mode Register */
83 #define LP5523_MODE_ENG2_M		0x0C
84 #define LP5523_MODE_ENG3_M		0x03
85 #define LP5523_LOAD_ENG1		0x10
86 #define LP5523_LOAD_ENG2		0x04
87 #define LP5523_LOAD_ENG3		0x01
88 
89 #define LP5523_ENG1_IS_LOADING(mode)	\
90 	((mode & LP5523_MODE_ENG1_M) == LP5523_LOAD_ENG1)
91 #define LP5523_ENG2_IS_LOADING(mode)	\
92 	((mode & LP5523_MODE_ENG2_M) == LP5523_LOAD_ENG2)
93 #define LP5523_ENG3_IS_LOADING(mode)	\
94 	((mode & LP5523_MODE_ENG3_M) == LP5523_LOAD_ENG3)
95 
96 #define LP5523_EXEC_ENG1_M		0x30	/* Enable Register */
97 #define LP5523_EXEC_ENG2_M		0x0C
98 #define LP5523_EXEC_ENG3_M		0x03
99 #define LP5523_EXEC_M			0x3F
100 #define LP5523_RUN_ENG1			0x20
101 #define LP5523_RUN_ENG2			0x08
102 #define LP5523_RUN_ENG3			0x02
103 
104 #define LED_ACTIVE(mux, led)		(!!(mux & (0x0001 << led)))
105 
106 enum lp5523_chip_id {
107 	LP5523,
108 	LP55231,
109 };
110 
111 static int lp5523_init_program_engine(struct lp55xx_chip *chip);
112 
113 static inline void lp5523_wait_opmode_done(void)
114 {
115 	usleep_range(1000, 2000);
116 }
117 
118 static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current)
119 {
120 	led->led_current = led_current;
121 	lp55xx_write(led->chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
122 		led_current);
123 }
124 
125 static int lp5523_post_init_device(struct lp55xx_chip *chip)
126 {
127 	int ret;
128 
129 	ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE);
130 	if (ret)
131 		return ret;
132 
133 	/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
134 	usleep_range(1000, 2000);
135 
136 	ret = lp55xx_write(chip, LP5523_REG_CONFIG,
137 			    LP5523_AUTO_INC | LP5523_PWR_SAVE |
138 			    LP5523_CP_AUTO | LP5523_AUTO_CLK |
139 			    LP5523_PWM_PWR_SAVE);
140 	if (ret)
141 		return ret;
142 
143 	/* turn on all leds */
144 	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
145 	if (ret)
146 		return ret;
147 
148 	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
149 	if (ret)
150 		return ret;
151 
152 	return lp5523_init_program_engine(chip);
153 }
154 
155 static void lp5523_load_engine(struct lp55xx_chip *chip)
156 {
157 	enum lp55xx_engine_index idx = chip->engine_idx;
158 	u8 mask[] = {
159 		[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
160 		[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
161 		[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
162 	};
163 
164 	u8 val[] = {
165 		[LP55XX_ENGINE_1] = LP5523_LOAD_ENG1,
166 		[LP55XX_ENGINE_2] = LP5523_LOAD_ENG2,
167 		[LP55XX_ENGINE_3] = LP5523_LOAD_ENG3,
168 	};
169 
170 	lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]);
171 
172 	lp5523_wait_opmode_done();
173 }
174 
175 static void lp5523_load_engine_and_select_page(struct lp55xx_chip *chip)
176 {
177 	enum lp55xx_engine_index idx = chip->engine_idx;
178 	u8 page_sel[] = {
179 		[LP55XX_ENGINE_1] = LP5523_PAGE_ENG1,
180 		[LP55XX_ENGINE_2] = LP5523_PAGE_ENG2,
181 		[LP55XX_ENGINE_3] = LP5523_PAGE_ENG3,
182 	};
183 
184 	lp5523_load_engine(chip);
185 
186 	lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]);
187 }
188 
189 static void lp5523_stop_engine(struct lp55xx_chip *chip)
190 {
191 	lp55xx_write(chip, LP5523_REG_OP_MODE, 0);
192 	lp5523_wait_opmode_done();
193 }
194 
195 static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
196 {
197 	int i;
198 
199 	for (i = 0; i < LP5523_MAX_LEDS; i++)
200 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
201 }
202 
203 static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
204 {
205 	int ret;
206 	u8 mode;
207 	u8 exec;
208 
209 	/* stop engine */
210 	if (!start) {
211 		lp5523_stop_engine(chip);
212 		lp5523_turn_off_channels(chip);
213 		return;
214 	}
215 
216 	/*
217 	 * To run the engine,
218 	 * operation mode and enable register should updated at the same time
219 	 */
220 
221 	ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
222 	if (ret)
223 		return;
224 
225 	ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
226 	if (ret)
227 		return;
228 
229 	/* change operation mode to RUN only when each engine is loading */
230 	if (LP5523_ENG1_IS_LOADING(mode)) {
231 		mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
232 		exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
233 	}
234 
235 	if (LP5523_ENG2_IS_LOADING(mode)) {
236 		mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
237 		exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
238 	}
239 
240 	if (LP5523_ENG3_IS_LOADING(mode)) {
241 		mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
242 		exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
243 	}
244 
245 	lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
246 	lp5523_wait_opmode_done();
247 
248 	lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
249 }
250 
251 static int lp5523_init_program_engine(struct lp55xx_chip *chip)
252 {
253 	int i;
254 	int j;
255 	int ret;
256 	u8 status;
257 	/* one pattern per engine setting LED MUX start and stop addresses */
258 	static const u8 pattern[][LP5523_PROGRAM_LENGTH] =  {
259 		{ 0x9c, 0x30, 0x9c, 0xb0, 0x9d, 0x80, 0xd8, 0x00, 0},
260 		{ 0x9c, 0x40, 0x9c, 0xc0, 0x9d, 0x80, 0xd8, 0x00, 0},
261 		{ 0x9c, 0x50, 0x9c, 0xd0, 0x9d, 0x80, 0xd8, 0x00, 0},
262 	};
263 
264 	/* hardcode 32 bytes of memory for each engine from program memory */
265 	ret = lp55xx_write(chip, LP5523_REG_CH1_PROG_START, 0x00);
266 	if (ret)
267 		return ret;
268 
269 	ret = lp55xx_write(chip, LP5523_REG_CH2_PROG_START, 0x10);
270 	if (ret)
271 		return ret;
272 
273 	ret = lp55xx_write(chip, LP5523_REG_CH3_PROG_START, 0x20);
274 	if (ret)
275 		return ret;
276 
277 	/* write LED MUX address space for each engine */
278 	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
279 		chip->engine_idx = i;
280 		lp5523_load_engine_and_select_page(chip);
281 
282 		for (j = 0; j < LP5523_PROGRAM_LENGTH; j++) {
283 			ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + j,
284 					pattern[i - 1][j]);
285 			if (ret)
286 				goto out;
287 		}
288 	}
289 
290 	lp5523_run_engine(chip, true);
291 
292 	/* Let the programs run for couple of ms and check the engine status */
293 	usleep_range(3000, 6000);
294 	lp55xx_read(chip, LP5523_REG_STATUS, &status);
295 	status &= LP5523_ENG_STATUS_MASK;
296 
297 	if (status != LP5523_ENG_STATUS_MASK) {
298 		dev_err(&chip->cl->dev,
299 			"cound not configure LED engine, status = 0x%.2x\n",
300 			status);
301 		ret = -1;
302 	}
303 
304 out:
305 	lp5523_stop_engine(chip);
306 	return ret;
307 }
308 
309 static int lp5523_update_program_memory(struct lp55xx_chip *chip,
310 					const u8 *data, size_t size)
311 {
312 	u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
313 	unsigned cmd;
314 	char c[3];
315 	int nrchars;
316 	int ret;
317 	int offset = 0;
318 	int i = 0;
319 
320 	while ((offset < size - 1) && (i < LP5523_PROGRAM_LENGTH)) {
321 		/* separate sscanfs because length is working only for %s */
322 		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
323 		if (ret != 1)
324 			goto err;
325 
326 		ret = sscanf(c, "%2x", &cmd);
327 		if (ret != 1)
328 			goto err;
329 
330 		pattern[i] = (u8)cmd;
331 		offset += nrchars;
332 		i++;
333 	}
334 
335 	/* Each instruction is 16bit long. Check that length is even */
336 	if (i % 2)
337 		goto err;
338 
339 	mutex_lock(&chip->lock);
340 
341 	for (i = 0; i < LP5523_PROGRAM_LENGTH; i++) {
342 		ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
343 		if (ret) {
344 			mutex_unlock(&chip->lock);
345 			return -EINVAL;
346 		}
347 	}
348 
349 	mutex_unlock(&chip->lock);
350 
351 	return size;
352 
353 err:
354 	dev_err(&chip->cl->dev, "wrong pattern format\n");
355 	return -EINVAL;
356 }
357 
358 static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
359 {
360 	const struct firmware *fw = chip->fw;
361 
362 	if (fw->size > LP5523_PROGRAM_LENGTH) {
363 		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
364 			fw->size);
365 		return;
366 	}
367 
368 	/*
369 	 * Program momery sequence
370 	 *  1) set engine mode to "LOAD"
371 	 *  2) write firmware data into program memory
372 	 */
373 
374 	lp5523_load_engine_and_select_page(chip);
375 	lp5523_update_program_memory(chip, fw->data, fw->size);
376 }
377 
378 static ssize_t show_engine_mode(struct device *dev,
379 				struct device_attribute *attr,
380 				char *buf, int nr)
381 {
382 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
383 	struct lp55xx_chip *chip = led->chip;
384 	enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
385 
386 	switch (mode) {
387 	case LP55XX_ENGINE_RUN:
388 		return sprintf(buf, "run\n");
389 	case LP55XX_ENGINE_LOAD:
390 		return sprintf(buf, "load\n");
391 	case LP55XX_ENGINE_DISABLED:
392 	default:
393 		return sprintf(buf, "disabled\n");
394 	}
395 }
396 show_mode(1)
397 show_mode(2)
398 show_mode(3)
399 
400 static ssize_t store_engine_mode(struct device *dev,
401 				 struct device_attribute *attr,
402 				 const char *buf, size_t len, int nr)
403 {
404 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
405 	struct lp55xx_chip *chip = led->chip;
406 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
407 
408 	mutex_lock(&chip->lock);
409 
410 	chip->engine_idx = nr;
411 
412 	if (!strncmp(buf, "run", 3)) {
413 		lp5523_run_engine(chip, true);
414 		engine->mode = LP55XX_ENGINE_RUN;
415 	} else if (!strncmp(buf, "load", 4)) {
416 		lp5523_stop_engine(chip);
417 		lp5523_load_engine(chip);
418 		engine->mode = LP55XX_ENGINE_LOAD;
419 	} else if (!strncmp(buf, "disabled", 8)) {
420 		lp5523_stop_engine(chip);
421 		engine->mode = LP55XX_ENGINE_DISABLED;
422 	}
423 
424 	mutex_unlock(&chip->lock);
425 
426 	return len;
427 }
428 store_mode(1)
429 store_mode(2)
430 store_mode(3)
431 
432 static int lp5523_mux_parse(const char *buf, u16 *mux, size_t len)
433 {
434 	u16 tmp_mux = 0;
435 	int i;
436 
437 	len = min_t(int, len, LP5523_MAX_LEDS);
438 
439 	for (i = 0; i < len; i++) {
440 		switch (buf[i]) {
441 		case '1':
442 			tmp_mux |= (1 << i);
443 			break;
444 		case '0':
445 			break;
446 		case '\n':
447 			i = len;
448 			break;
449 		default:
450 			return -1;
451 		}
452 	}
453 	*mux = tmp_mux;
454 
455 	return 0;
456 }
457 
458 static void lp5523_mux_to_array(u16 led_mux, char *array)
459 {
460 	int i, pos = 0;
461 	for (i = 0; i < LP5523_MAX_LEDS; i++)
462 		pos += sprintf(array + pos, "%x", LED_ACTIVE(led_mux, i));
463 
464 	array[pos] = '\0';
465 }
466 
467 static ssize_t show_engine_leds(struct device *dev,
468 			    struct device_attribute *attr,
469 			    char *buf, int nr)
470 {
471 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
472 	struct lp55xx_chip *chip = led->chip;
473 	char mux[LP5523_MAX_LEDS + 1];
474 
475 	lp5523_mux_to_array(chip->engines[nr - 1].led_mux, mux);
476 
477 	return sprintf(buf, "%s\n", mux);
478 }
479 show_leds(1)
480 show_leds(2)
481 show_leds(3)
482 
483 static int lp5523_load_mux(struct lp55xx_chip *chip, u16 mux, int nr)
484 {
485 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
486 	int ret;
487 	u8 mux_page[] = {
488 		[LP55XX_ENGINE_1] = LP5523_PAGE_MUX1,
489 		[LP55XX_ENGINE_2] = LP5523_PAGE_MUX2,
490 		[LP55XX_ENGINE_3] = LP5523_PAGE_MUX3,
491 	};
492 
493 	lp5523_load_engine(chip);
494 
495 	ret = lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, mux_page[nr]);
496 	if (ret)
497 		return ret;
498 
499 	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM , (u8)(mux >> 8));
500 	if (ret)
501 		return ret;
502 
503 	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + 1, (u8)(mux));
504 	if (ret)
505 		return ret;
506 
507 	engine->led_mux = mux;
508 	return 0;
509 }
510 
511 static ssize_t store_engine_leds(struct device *dev,
512 			     struct device_attribute *attr,
513 			     const char *buf, size_t len, int nr)
514 {
515 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
516 	struct lp55xx_chip *chip = led->chip;
517 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
518 	u16 mux = 0;
519 	ssize_t ret;
520 
521 	if (lp5523_mux_parse(buf, &mux, len))
522 		return -EINVAL;
523 
524 	mutex_lock(&chip->lock);
525 
526 	chip->engine_idx = nr;
527 	ret = -EINVAL;
528 
529 	if (engine->mode != LP55XX_ENGINE_LOAD)
530 		goto leave;
531 
532 	if (lp5523_load_mux(chip, mux, nr))
533 		goto leave;
534 
535 	ret = len;
536 leave:
537 	mutex_unlock(&chip->lock);
538 	return ret;
539 }
540 store_leds(1)
541 store_leds(2)
542 store_leds(3)
543 
544 static ssize_t store_engine_load(struct device *dev,
545 			     struct device_attribute *attr,
546 			     const char *buf, size_t len, int nr)
547 {
548 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
549 	struct lp55xx_chip *chip = led->chip;
550 
551 	mutex_lock(&chip->lock);
552 
553 	chip->engine_idx = nr;
554 	lp5523_load_engine_and_select_page(chip);
555 
556 	mutex_unlock(&chip->lock);
557 
558 	return lp5523_update_program_memory(chip, buf, len);
559 }
560 store_load(1)
561 store_load(2)
562 store_load(3)
563 
564 static ssize_t lp5523_selftest(struct device *dev,
565 			       struct device_attribute *attr,
566 			       char *buf)
567 {
568 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
569 	struct lp55xx_chip *chip = led->chip;
570 	struct lp55xx_platform_data *pdata = chip->pdata;
571 	int i, ret, pos = 0;
572 	u8 status, adc, vdd;
573 
574 	mutex_lock(&chip->lock);
575 
576 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
577 	if (ret < 0)
578 		goto fail;
579 
580 	/* Check that ext clock is really in use if requested */
581 	if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
582 		if  ((status & LP5523_EXT_CLK_USED) == 0)
583 			goto fail;
584 	}
585 
586 	/* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
587 	lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
588 	usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
589 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
590 	if (ret < 0)
591 		goto fail;
592 
593 	if (!(status & LP5523_LEDTEST_DONE))
594 		usleep_range(3000, 6000); /* Was not ready. Wait little bit */
595 
596 	ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
597 	if (ret < 0)
598 		goto fail;
599 
600 	vdd--;	/* There may be some fluctuation in measurement */
601 
602 	for (i = 0; i < LP5523_MAX_LEDS; i++) {
603 		/* Skip non-existing channels */
604 		if (pdata->led_config[i].led_current == 0)
605 			continue;
606 
607 		/* Set default current */
608 		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
609 			pdata->led_config[i].led_current);
610 
611 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff);
612 		/* let current stabilize 2 - 4ms before measurements start */
613 		usleep_range(2000, 4000);
614 		lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL,
615 			     LP5523_EN_LEDTEST | i);
616 		/* ADC conversion time is 2.7 ms typically */
617 		usleep_range(3000, 6000);
618 		ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
619 		if (ret < 0)
620 			goto fail;
621 
622 		if (!(status & LP5523_LEDTEST_DONE))
623 			usleep_range(3000, 6000);/* Was not ready. Wait. */
624 
625 		ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc);
626 		if (ret < 0)
627 			goto fail;
628 
629 		if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
630 			pos += sprintf(buf + pos, "LED %d FAIL\n", i);
631 
632 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00);
633 
634 		/* Restore current */
635 		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
636 			led->led_current);
637 		led++;
638 	}
639 	if (pos == 0)
640 		pos = sprintf(buf, "OK\n");
641 	goto release_lock;
642 fail:
643 	pos = sprintf(buf, "FAIL\n");
644 
645 release_lock:
646 	mutex_unlock(&chip->lock);
647 
648 	return pos;
649 }
650 
651 static void lp5523_led_brightness_work(struct work_struct *work)
652 {
653 	struct lp55xx_led *led = container_of(work, struct lp55xx_led,
654 					      brightness_work);
655 	struct lp55xx_chip *chip = led->chip;
656 
657 	mutex_lock(&chip->lock);
658 	lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
659 		     led->brightness);
660 	mutex_unlock(&chip->lock);
661 }
662 
663 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
664 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
665 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
666 static LP55XX_DEV_ATTR_RW(engine1_leds, show_engine1_leds, store_engine1_leds);
667 static LP55XX_DEV_ATTR_RW(engine2_leds, show_engine2_leds, store_engine2_leds);
668 static LP55XX_DEV_ATTR_RW(engine3_leds, show_engine3_leds, store_engine3_leds);
669 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
670 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
671 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
672 static LP55XX_DEV_ATTR_RO(selftest, lp5523_selftest);
673 
674 static struct attribute *lp5523_attributes[] = {
675 	&dev_attr_engine1_mode.attr,
676 	&dev_attr_engine2_mode.attr,
677 	&dev_attr_engine3_mode.attr,
678 	&dev_attr_engine1_load.attr,
679 	&dev_attr_engine2_load.attr,
680 	&dev_attr_engine3_load.attr,
681 	&dev_attr_engine1_leds.attr,
682 	&dev_attr_engine2_leds.attr,
683 	&dev_attr_engine3_leds.attr,
684 	&dev_attr_selftest.attr,
685 	NULL,
686 };
687 
688 static const struct attribute_group lp5523_group = {
689 	.attrs = lp5523_attributes,
690 };
691 
692 /* Chip specific configurations */
693 static struct lp55xx_device_config lp5523_cfg = {
694 	.reset = {
695 		.addr = LP5523_REG_RESET,
696 		.val  = LP5523_RESET,
697 	},
698 	.enable = {
699 		.addr = LP5523_REG_ENABLE,
700 		.val  = LP5523_ENABLE,
701 	},
702 	.max_channel  = LP5523_MAX_LEDS,
703 	.post_init_device   = lp5523_post_init_device,
704 	.brightness_work_fn = lp5523_led_brightness_work,
705 	.set_led_current    = lp5523_set_led_current,
706 	.firmware_cb        = lp5523_firmware_loaded,
707 	.run_engine         = lp5523_run_engine,
708 	.dev_attr_group     = &lp5523_group,
709 };
710 
711 static int lp5523_probe(struct i2c_client *client,
712 			const struct i2c_device_id *id)
713 {
714 	int ret;
715 	struct lp55xx_chip *chip;
716 	struct lp55xx_led *led;
717 	struct lp55xx_platform_data *pdata;
718 	struct device_node *np = client->dev.of_node;
719 
720 	if (!dev_get_platdata(&client->dev)) {
721 		if (np) {
722 			ret = lp55xx_of_populate_pdata(&client->dev, np);
723 			if (ret < 0)
724 				return ret;
725 		} else {
726 			dev_err(&client->dev, "no platform data\n");
727 			return -EINVAL;
728 		}
729 	}
730 	pdata = dev_get_platdata(&client->dev);
731 
732 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
733 	if (!chip)
734 		return -ENOMEM;
735 
736 	led = devm_kzalloc(&client->dev,
737 			sizeof(*led) * pdata->num_channels, GFP_KERNEL);
738 	if (!led)
739 		return -ENOMEM;
740 
741 	chip->cl = client;
742 	chip->pdata = pdata;
743 	chip->cfg = &lp5523_cfg;
744 
745 	mutex_init(&chip->lock);
746 
747 	i2c_set_clientdata(client, led);
748 
749 	ret = lp55xx_init_device(chip);
750 	if (ret)
751 		goto err_init;
752 
753 	dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
754 
755 	ret = lp55xx_register_leds(led, chip);
756 	if (ret)
757 		goto err_register_leds;
758 
759 	ret = lp55xx_register_sysfs(chip);
760 	if (ret) {
761 		dev_err(&client->dev, "registering sysfs failed\n");
762 		goto err_register_sysfs;
763 	}
764 
765 	return 0;
766 
767 err_register_sysfs:
768 	lp55xx_unregister_leds(led, chip);
769 err_register_leds:
770 	lp55xx_deinit_device(chip);
771 err_init:
772 	return ret;
773 }
774 
775 static int lp5523_remove(struct i2c_client *client)
776 {
777 	struct lp55xx_led *led = i2c_get_clientdata(client);
778 	struct lp55xx_chip *chip = led->chip;
779 
780 	lp5523_stop_engine(chip);
781 	lp55xx_unregister_sysfs(chip);
782 	lp55xx_unregister_leds(led, chip);
783 	lp55xx_deinit_device(chip);
784 
785 	return 0;
786 }
787 
788 static const struct i2c_device_id lp5523_id[] = {
789 	{ "lp5523",  LP5523 },
790 	{ "lp55231", LP55231 },
791 	{ }
792 };
793 
794 MODULE_DEVICE_TABLE(i2c, lp5523_id);
795 
796 #ifdef CONFIG_OF
797 static const struct of_device_id of_lp5523_leds_match[] = {
798 	{ .compatible = "national,lp5523", },
799 	{},
800 };
801 
802 MODULE_DEVICE_TABLE(of, of_lp5523_leds_match);
803 #endif
804 
805 static struct i2c_driver lp5523_driver = {
806 	.driver = {
807 		.name	= "lp5523x",
808 		.of_match_table = of_match_ptr(of_lp5523_leds_match),
809 	},
810 	.probe		= lp5523_probe,
811 	.remove		= lp5523_remove,
812 	.id_table	= lp5523_id,
813 };
814 
815 module_i2c_driver(lp5523_driver);
816 
817 MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
818 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
819 MODULE_DESCRIPTION("LP5523 LED engine");
820 MODULE_LICENSE("GPL");
821