xref: /openbmc/linux/drivers/leds/leds-lp5523.c (revision 6db6b729)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * lp5523.c - LP5523, LP55231 LED Driver
4  *
5  * Copyright (C) 2010 Nokia Corporation
6  * Copyright (C) 2012 Texas Instruments
7  *
8  * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
9  *          Milo(Woogyom) Kim <milo.kim@ti.com>
10  */
11 
12 #include <linux/delay.h>
13 #include <linux/firmware.h>
14 #include <linux/i2c.h>
15 #include <linux/leds.h>
16 #include <linux/module.h>
17 #include <linux/mutex.h>
18 #include <linux/of.h>
19 #include <linux/platform_data/leds-lp55xx.h>
20 #include <linux/slab.h>
21 
22 #include "leds-lp55xx-common.h"
23 
24 #define LP5523_PROGRAM_LENGTH		32	/* bytes */
25 /* Memory is used like this:
26  * 0x00 engine 1 program
27  * 0x10 engine 2 program
28  * 0x20 engine 3 program
29  * 0x30 engine 1 muxing info
30  * 0x40 engine 2 muxing info
31  * 0x50 engine 3 muxing info
32  */
33 #define LP5523_MAX_LEDS			9
34 
35 /* Registers */
36 #define LP5523_REG_ENABLE		0x00
37 #define LP5523_REG_OP_MODE		0x01
38 #define LP5523_REG_ENABLE_LEDS_MSB	0x04
39 #define LP5523_REG_ENABLE_LEDS_LSB	0x05
40 #define LP5523_REG_LED_CTRL_BASE	0x06
41 #define LP5523_REG_LED_PWM_BASE		0x16
42 #define LP5523_REG_LED_CURRENT_BASE	0x26
43 #define LP5523_REG_CONFIG		0x36
44 #define LP5523_REG_STATUS		0x3A
45 #define LP5523_REG_RESET		0x3D
46 #define LP5523_REG_LED_TEST_CTRL	0x41
47 #define LP5523_REG_LED_TEST_ADC		0x42
48 #define LP5523_REG_MASTER_FADER_BASE	0x48
49 #define LP5523_REG_CH1_PROG_START	0x4C
50 #define LP5523_REG_CH2_PROG_START	0x4D
51 #define LP5523_REG_CH3_PROG_START	0x4E
52 #define LP5523_REG_PROG_PAGE_SEL	0x4F
53 #define LP5523_REG_PROG_MEM		0x50
54 
55 /* Bit description in registers */
56 #define LP5523_ENABLE			0x40
57 #define LP5523_AUTO_INC			0x40
58 #define LP5523_PWR_SAVE			0x20
59 #define LP5523_PWM_PWR_SAVE		0x04
60 #define LP5523_CP_MODE_MASK		0x18
61 #define LP5523_CP_MODE_SHIFT		3
62 #define LP5523_AUTO_CLK			0x02
63 #define LP5523_DEFAULT_CONFIG \
64 	(LP5523_AUTO_INC | LP5523_PWR_SAVE | LP5523_AUTO_CLK | LP5523_PWM_PWR_SAVE)
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 #define LP5523_FADER_MAPPING_MASK	0xC0
74 #define LP5523_FADER_MAPPING_SHIFT	6
75 
76 /* Memory Page Selection */
77 #define LP5523_PAGE_ENG1		0
78 #define LP5523_PAGE_ENG2		1
79 #define LP5523_PAGE_ENG3		2
80 #define LP5523_PAGE_MUX1		3
81 #define LP5523_PAGE_MUX2		4
82 #define LP5523_PAGE_MUX3		5
83 
84 /* Program Memory Operations */
85 #define LP5523_MODE_ENG1_M		0x30	/* Operation Mode Register */
86 #define LP5523_MODE_ENG2_M		0x0C
87 #define LP5523_MODE_ENG3_M		0x03
88 #define LP5523_LOAD_ENG1		0x10
89 #define LP5523_LOAD_ENG2		0x04
90 #define LP5523_LOAD_ENG3		0x01
91 
92 #define LP5523_ENG1_IS_LOADING(mode)	\
93 	((mode & LP5523_MODE_ENG1_M) == LP5523_LOAD_ENG1)
94 #define LP5523_ENG2_IS_LOADING(mode)	\
95 	((mode & LP5523_MODE_ENG2_M) == LP5523_LOAD_ENG2)
96 #define LP5523_ENG3_IS_LOADING(mode)	\
97 	((mode & LP5523_MODE_ENG3_M) == LP5523_LOAD_ENG3)
98 
99 #define LP5523_EXEC_ENG1_M		0x30	/* Enable Register */
100 #define LP5523_EXEC_ENG2_M		0x0C
101 #define LP5523_EXEC_ENG3_M		0x03
102 #define LP5523_EXEC_M			0x3F
103 #define LP5523_RUN_ENG1			0x20
104 #define LP5523_RUN_ENG2			0x08
105 #define LP5523_RUN_ENG3			0x02
106 
107 #define LED_ACTIVE(mux, led)		(!!(mux & (0x0001 << led)))
108 
109 enum lp5523_chip_id {
110 	LP5523,
111 	LP55231,
112 };
113 
114 static int lp5523_init_program_engine(struct lp55xx_chip *chip);
115 
116 static inline void lp5523_wait_opmode_done(void)
117 {
118 	usleep_range(1000, 2000);
119 }
120 
121 static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current)
122 {
123 	led->led_current = led_current;
124 	lp55xx_write(led->chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
125 		led_current);
126 }
127 
128 static int lp5523_post_init_device(struct lp55xx_chip *chip)
129 {
130 	int ret;
131 	int val;
132 
133 	ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE);
134 	if (ret)
135 		return ret;
136 
137 	/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
138 	usleep_range(1000, 2000);
139 
140 	val = LP5523_DEFAULT_CONFIG;
141 	val |= (chip->pdata->charge_pump_mode << LP5523_CP_MODE_SHIFT) & LP5523_CP_MODE_MASK;
142 
143 	ret = lp55xx_write(chip, LP5523_REG_CONFIG, val);
144 	if (ret)
145 		return ret;
146 
147 	/* turn on all leds */
148 	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
149 	if (ret)
150 		return ret;
151 
152 	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
153 	if (ret)
154 		return ret;
155 
156 	return lp5523_init_program_engine(chip);
157 }
158 
159 static void lp5523_load_engine(struct lp55xx_chip *chip)
160 {
161 	enum lp55xx_engine_index idx = chip->engine_idx;
162 	static const u8 mask[] = {
163 		[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
164 		[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
165 		[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
166 	};
167 
168 	static const u8 val[] = {
169 		[LP55XX_ENGINE_1] = LP5523_LOAD_ENG1,
170 		[LP55XX_ENGINE_2] = LP5523_LOAD_ENG2,
171 		[LP55XX_ENGINE_3] = LP5523_LOAD_ENG3,
172 	};
173 
174 	lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]);
175 
176 	lp5523_wait_opmode_done();
177 }
178 
179 static void lp5523_load_engine_and_select_page(struct lp55xx_chip *chip)
180 {
181 	enum lp55xx_engine_index idx = chip->engine_idx;
182 	static const u8 page_sel[] = {
183 		[LP55XX_ENGINE_1] = LP5523_PAGE_ENG1,
184 		[LP55XX_ENGINE_2] = LP5523_PAGE_ENG2,
185 		[LP55XX_ENGINE_3] = LP5523_PAGE_ENG3,
186 	};
187 
188 	lp5523_load_engine(chip);
189 
190 	lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]);
191 }
192 
193 static void lp5523_stop_all_engines(struct lp55xx_chip *chip)
194 {
195 	lp55xx_write(chip, LP5523_REG_OP_MODE, 0);
196 	lp5523_wait_opmode_done();
197 }
198 
199 static void lp5523_stop_engine(struct lp55xx_chip *chip)
200 {
201 	enum lp55xx_engine_index idx = chip->engine_idx;
202 	static const u8 mask[] = {
203 		[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
204 		[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
205 		[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
206 	};
207 
208 	lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], 0);
209 
210 	lp5523_wait_opmode_done();
211 }
212 
213 static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
214 {
215 	int i;
216 
217 	for (i = 0; i < LP5523_MAX_LEDS; i++)
218 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
219 }
220 
221 static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
222 {
223 	int ret;
224 	u8 mode;
225 	u8 exec;
226 
227 	/* stop engine */
228 	if (!start) {
229 		lp5523_stop_engine(chip);
230 		lp5523_turn_off_channels(chip);
231 		return;
232 	}
233 
234 	/*
235 	 * To run the engine,
236 	 * operation mode and enable register should updated at the same time
237 	 */
238 
239 	ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
240 	if (ret)
241 		return;
242 
243 	ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
244 	if (ret)
245 		return;
246 
247 	/* change operation mode to RUN only when each engine is loading */
248 	if (LP5523_ENG1_IS_LOADING(mode)) {
249 		mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
250 		exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
251 	}
252 
253 	if (LP5523_ENG2_IS_LOADING(mode)) {
254 		mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
255 		exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
256 	}
257 
258 	if (LP5523_ENG3_IS_LOADING(mode)) {
259 		mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
260 		exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
261 	}
262 
263 	lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
264 	lp5523_wait_opmode_done();
265 
266 	lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
267 }
268 
269 static int lp5523_init_program_engine(struct lp55xx_chip *chip)
270 {
271 	int i;
272 	int j;
273 	int ret;
274 	u8 status;
275 	/* one pattern per engine setting LED MUX start and stop addresses */
276 	static const u8 pattern[][LP5523_PROGRAM_LENGTH] =  {
277 		{ 0x9c, 0x30, 0x9c, 0xb0, 0x9d, 0x80, 0xd8, 0x00, 0},
278 		{ 0x9c, 0x40, 0x9c, 0xc0, 0x9d, 0x80, 0xd8, 0x00, 0},
279 		{ 0x9c, 0x50, 0x9c, 0xd0, 0x9d, 0x80, 0xd8, 0x00, 0},
280 	};
281 
282 	/* hardcode 32 bytes of memory for each engine from program memory */
283 	ret = lp55xx_write(chip, LP5523_REG_CH1_PROG_START, 0x00);
284 	if (ret)
285 		return ret;
286 
287 	ret = lp55xx_write(chip, LP5523_REG_CH2_PROG_START, 0x10);
288 	if (ret)
289 		return ret;
290 
291 	ret = lp55xx_write(chip, LP5523_REG_CH3_PROG_START, 0x20);
292 	if (ret)
293 		return ret;
294 
295 	/* write LED MUX address space for each engine */
296 	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
297 		chip->engine_idx = i;
298 		lp5523_load_engine_and_select_page(chip);
299 
300 		for (j = 0; j < LP5523_PROGRAM_LENGTH; j++) {
301 			ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + j,
302 					pattern[i - 1][j]);
303 			if (ret)
304 				goto out;
305 		}
306 	}
307 
308 	lp5523_run_engine(chip, true);
309 
310 	/* Let the programs run for couple of ms and check the engine status */
311 	usleep_range(3000, 6000);
312 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
313 	if (ret)
314 		goto out;
315 	status &= LP5523_ENG_STATUS_MASK;
316 
317 	if (status != LP5523_ENG_STATUS_MASK) {
318 		dev_err(&chip->cl->dev,
319 			"could not configure LED engine, status = 0x%.2x\n",
320 			status);
321 		ret = -1;
322 	}
323 
324 out:
325 	lp5523_stop_all_engines(chip);
326 	return ret;
327 }
328 
329 static int lp5523_update_program_memory(struct lp55xx_chip *chip,
330 					const u8 *data, size_t size)
331 {
332 	u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
333 	unsigned int cmd;
334 	char c[3];
335 	int nrchars;
336 	int ret;
337 	int offset = 0;
338 	int i = 0;
339 
340 	while ((offset < size - 1) && (i < LP5523_PROGRAM_LENGTH)) {
341 		/* separate sscanfs because length is working only for %s */
342 		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
343 		if (ret != 1)
344 			goto err;
345 
346 		ret = sscanf(c, "%2x", &cmd);
347 		if (ret != 1)
348 			goto err;
349 
350 		pattern[i] = (u8)cmd;
351 		offset += nrchars;
352 		i++;
353 	}
354 
355 	/* Each instruction is 16bit long. Check that length is even */
356 	if (i % 2)
357 		goto err;
358 
359 	for (i = 0; i < LP5523_PROGRAM_LENGTH; i++) {
360 		ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
361 		if (ret)
362 			return -EINVAL;
363 	}
364 
365 	return size;
366 
367 err:
368 	dev_err(&chip->cl->dev, "wrong pattern format\n");
369 	return -EINVAL;
370 }
371 
372 static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
373 {
374 	const struct firmware *fw = chip->fw;
375 
376 	if (fw->size > LP5523_PROGRAM_LENGTH) {
377 		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
378 			fw->size);
379 		return;
380 	}
381 
382 	/*
383 	 * Program memory sequence
384 	 *  1) set engine mode to "LOAD"
385 	 *  2) write firmware data into program memory
386 	 */
387 
388 	lp5523_load_engine_and_select_page(chip);
389 	lp5523_update_program_memory(chip, fw->data, fw->size);
390 }
391 
392 static ssize_t show_engine_mode(struct device *dev,
393 				struct device_attribute *attr,
394 				char *buf, int nr)
395 {
396 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
397 	struct lp55xx_chip *chip = led->chip;
398 	enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
399 
400 	switch (mode) {
401 	case LP55XX_ENGINE_RUN:
402 		return sprintf(buf, "run\n");
403 	case LP55XX_ENGINE_LOAD:
404 		return sprintf(buf, "load\n");
405 	case LP55XX_ENGINE_DISABLED:
406 	default:
407 		return sprintf(buf, "disabled\n");
408 	}
409 }
410 show_mode(1)
411 show_mode(2)
412 show_mode(3)
413 
414 static ssize_t store_engine_mode(struct device *dev,
415 				 struct device_attribute *attr,
416 				 const char *buf, size_t len, int nr)
417 {
418 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
419 	struct lp55xx_chip *chip = led->chip;
420 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
421 
422 	mutex_lock(&chip->lock);
423 
424 	chip->engine_idx = nr;
425 
426 	if (!strncmp(buf, "run", 3)) {
427 		lp5523_run_engine(chip, true);
428 		engine->mode = LP55XX_ENGINE_RUN;
429 	} else if (!strncmp(buf, "load", 4)) {
430 		lp5523_stop_engine(chip);
431 		lp5523_load_engine(chip);
432 		engine->mode = LP55XX_ENGINE_LOAD;
433 	} else if (!strncmp(buf, "disabled", 8)) {
434 		lp5523_stop_engine(chip);
435 		engine->mode = LP55XX_ENGINE_DISABLED;
436 	}
437 
438 	mutex_unlock(&chip->lock);
439 
440 	return len;
441 }
442 store_mode(1)
443 store_mode(2)
444 store_mode(3)
445 
446 static int lp5523_mux_parse(const char *buf, u16 *mux, size_t len)
447 {
448 	u16 tmp_mux = 0;
449 	int i;
450 
451 	len = min_t(int, len, LP5523_MAX_LEDS);
452 
453 	for (i = 0; i < len; i++) {
454 		switch (buf[i]) {
455 		case '1':
456 			tmp_mux |= (1 << i);
457 			break;
458 		case '0':
459 			break;
460 		case '\n':
461 			i = len;
462 			break;
463 		default:
464 			return -1;
465 		}
466 	}
467 	*mux = tmp_mux;
468 
469 	return 0;
470 }
471 
472 static void lp5523_mux_to_array(u16 led_mux, char *array)
473 {
474 	int i, pos = 0;
475 
476 	for (i = 0; i < LP5523_MAX_LEDS; i++)
477 		pos += sprintf(array + pos, "%x", LED_ACTIVE(led_mux, i));
478 
479 	array[pos] = '\0';
480 }
481 
482 static ssize_t show_engine_leds(struct device *dev,
483 			    struct device_attribute *attr,
484 			    char *buf, int nr)
485 {
486 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
487 	struct lp55xx_chip *chip = led->chip;
488 	char mux[LP5523_MAX_LEDS + 1];
489 
490 	lp5523_mux_to_array(chip->engines[nr - 1].led_mux, mux);
491 
492 	return sprintf(buf, "%s\n", mux);
493 }
494 show_leds(1)
495 show_leds(2)
496 show_leds(3)
497 
498 static int lp5523_load_mux(struct lp55xx_chip *chip, u16 mux, int nr)
499 {
500 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
501 	int ret;
502 	static const u8 mux_page[] = {
503 		[LP55XX_ENGINE_1] = LP5523_PAGE_MUX1,
504 		[LP55XX_ENGINE_2] = LP5523_PAGE_MUX2,
505 		[LP55XX_ENGINE_3] = LP5523_PAGE_MUX3,
506 	};
507 
508 	lp5523_load_engine(chip);
509 
510 	ret = lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, mux_page[nr]);
511 	if (ret)
512 		return ret;
513 
514 	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM, (u8)(mux >> 8));
515 	if (ret)
516 		return ret;
517 
518 	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + 1, (u8)(mux));
519 	if (ret)
520 		return ret;
521 
522 	engine->led_mux = mux;
523 	return 0;
524 }
525 
526 static ssize_t store_engine_leds(struct device *dev,
527 			     struct device_attribute *attr,
528 			     const char *buf, size_t len, int nr)
529 {
530 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
531 	struct lp55xx_chip *chip = led->chip;
532 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
533 	u16 mux = 0;
534 	ssize_t ret;
535 
536 	if (lp5523_mux_parse(buf, &mux, len))
537 		return -EINVAL;
538 
539 	mutex_lock(&chip->lock);
540 
541 	chip->engine_idx = nr;
542 	ret = -EINVAL;
543 
544 	if (engine->mode != LP55XX_ENGINE_LOAD)
545 		goto leave;
546 
547 	if (lp5523_load_mux(chip, mux, nr))
548 		goto leave;
549 
550 	ret = len;
551 leave:
552 	mutex_unlock(&chip->lock);
553 	return ret;
554 }
555 store_leds(1)
556 store_leds(2)
557 store_leds(3)
558 
559 static ssize_t store_engine_load(struct device *dev,
560 			     struct device_attribute *attr,
561 			     const char *buf, size_t len, int nr)
562 {
563 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
564 	struct lp55xx_chip *chip = led->chip;
565 	int ret;
566 
567 	mutex_lock(&chip->lock);
568 
569 	chip->engine_idx = nr;
570 	lp5523_load_engine_and_select_page(chip);
571 	ret = lp5523_update_program_memory(chip, buf, len);
572 
573 	mutex_unlock(&chip->lock);
574 
575 	return ret;
576 }
577 store_load(1)
578 store_load(2)
579 store_load(3)
580 
581 static ssize_t lp5523_selftest(struct device *dev,
582 			       struct device_attribute *attr,
583 			       char *buf)
584 {
585 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
586 	struct lp55xx_chip *chip = led->chip;
587 	struct lp55xx_platform_data *pdata = chip->pdata;
588 	int ret, pos = 0;
589 	u8 status, adc, vdd, i;
590 
591 	mutex_lock(&chip->lock);
592 
593 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
594 	if (ret < 0)
595 		goto fail;
596 
597 	/* Check that ext clock is really in use if requested */
598 	if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
599 		if  ((status & LP5523_EXT_CLK_USED) == 0)
600 			goto fail;
601 	}
602 
603 	/* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
604 	lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
605 	usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
606 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
607 	if (ret < 0)
608 		goto fail;
609 
610 	if (!(status & LP5523_LEDTEST_DONE))
611 		usleep_range(3000, 6000); /* Was not ready. Wait little bit */
612 
613 	ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
614 	if (ret < 0)
615 		goto fail;
616 
617 	vdd--;	/* There may be some fluctuation in measurement */
618 
619 	for (i = 0; i < pdata->num_channels; i++) {
620 		/* Skip disabled channels */
621 		if (pdata->led_config[i].led_current == 0)
622 			continue;
623 
624 		/* Set default current */
625 		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
626 			pdata->led_config[i].led_current);
627 
628 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
629 			     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 | led->chan_nr);
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",
649 				       led->chan_nr);
650 
651 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
652 			     0x00);
653 
654 		/* Restore current */
655 		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
656 			     led->led_current);
657 		led++;
658 	}
659 	if (pos == 0)
660 		pos = sprintf(buf, "OK\n");
661 	goto release_lock;
662 fail:
663 	pos = sprintf(buf, "FAIL\n");
664 
665 release_lock:
666 	mutex_unlock(&chip->lock);
667 
668 	return pos;
669 }
670 
671 #define show_fader(nr)						\
672 static ssize_t show_master_fader##nr(struct device *dev,	\
673 			    struct device_attribute *attr,	\
674 			    char *buf)				\
675 {								\
676 	return show_master_fader(dev, attr, buf, nr);		\
677 }
678 
679 #define store_fader(nr)						\
680 static ssize_t store_master_fader##nr(struct device *dev,	\
681 			     struct device_attribute *attr,	\
682 			     const char *buf, size_t len)	\
683 {								\
684 	return store_master_fader(dev, attr, buf, len, nr);	\
685 }
686 
687 static ssize_t show_master_fader(struct device *dev,
688 				 struct device_attribute *attr,
689 				 char *buf, int nr)
690 {
691 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
692 	struct lp55xx_chip *chip = led->chip;
693 	int ret;
694 	u8 val;
695 
696 	mutex_lock(&chip->lock);
697 	ret = lp55xx_read(chip, LP5523_REG_MASTER_FADER_BASE + nr - 1, &val);
698 	mutex_unlock(&chip->lock);
699 
700 	if (ret == 0)
701 		ret = sprintf(buf, "%u\n", val);
702 
703 	return ret;
704 }
705 show_fader(1)
706 show_fader(2)
707 show_fader(3)
708 
709 static ssize_t store_master_fader(struct device *dev,
710 				  struct device_attribute *attr,
711 				  const char *buf, size_t len, int nr)
712 {
713 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
714 	struct lp55xx_chip *chip = led->chip;
715 	int ret;
716 	unsigned long val;
717 
718 	if (kstrtoul(buf, 0, &val))
719 		return -EINVAL;
720 
721 	if (val > 0xff)
722 		return -EINVAL;
723 
724 	mutex_lock(&chip->lock);
725 	ret = lp55xx_write(chip, LP5523_REG_MASTER_FADER_BASE + nr - 1,
726 			   (u8)val);
727 	mutex_unlock(&chip->lock);
728 
729 	if (ret == 0)
730 		ret = len;
731 
732 	return ret;
733 }
734 store_fader(1)
735 store_fader(2)
736 store_fader(3)
737 
738 static ssize_t show_master_fader_leds(struct device *dev,
739 				      struct device_attribute *attr,
740 				      char *buf)
741 {
742 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
743 	struct lp55xx_chip *chip = led->chip;
744 	int i, ret, pos = 0;
745 	u8 val;
746 
747 	mutex_lock(&chip->lock);
748 
749 	for (i = 0; i < LP5523_MAX_LEDS; i++) {
750 		ret = lp55xx_read(chip, LP5523_REG_LED_CTRL_BASE + i, &val);
751 		if (ret)
752 			goto leave;
753 
754 		val = (val & LP5523_FADER_MAPPING_MASK)
755 			>> LP5523_FADER_MAPPING_SHIFT;
756 		if (val > 3) {
757 			ret = -EINVAL;
758 			goto leave;
759 		}
760 		buf[pos++] = val + '0';
761 	}
762 	buf[pos++] = '\n';
763 	ret = pos;
764 leave:
765 	mutex_unlock(&chip->lock);
766 	return ret;
767 }
768 
769 static ssize_t store_master_fader_leds(struct device *dev,
770 				       struct device_attribute *attr,
771 				       const char *buf, size_t len)
772 {
773 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
774 	struct lp55xx_chip *chip = led->chip;
775 	int i, n, ret;
776 	u8 val;
777 
778 	n = min_t(int, len, LP5523_MAX_LEDS);
779 
780 	mutex_lock(&chip->lock);
781 
782 	for (i = 0; i < n; i++) {
783 		if (buf[i] >= '0' && buf[i] <= '3') {
784 			val = (buf[i] - '0') << LP5523_FADER_MAPPING_SHIFT;
785 			ret = lp55xx_update_bits(chip,
786 						 LP5523_REG_LED_CTRL_BASE + i,
787 						 LP5523_FADER_MAPPING_MASK,
788 						 val);
789 			if (ret)
790 				goto leave;
791 		} else {
792 			ret = -EINVAL;
793 			goto leave;
794 		}
795 	}
796 	ret = len;
797 leave:
798 	mutex_unlock(&chip->lock);
799 	return ret;
800 }
801 
802 static int lp5523_multicolor_brightness(struct lp55xx_led *led)
803 {
804 	struct lp55xx_chip *chip = led->chip;
805 	int ret;
806 	int i;
807 
808 	mutex_lock(&chip->lock);
809 	for (i = 0; i < led->mc_cdev.num_colors; i++) {
810 		ret = lp55xx_write(chip,
811 				   LP5523_REG_LED_PWM_BASE +
812 				   led->mc_cdev.subled_info[i].channel,
813 				   led->mc_cdev.subled_info[i].brightness);
814 		if (ret)
815 			break;
816 	}
817 	mutex_unlock(&chip->lock);
818 	return ret;
819 }
820 
821 static int lp5523_led_brightness(struct lp55xx_led *led)
822 {
823 	struct lp55xx_chip *chip = led->chip;
824 	int ret;
825 
826 	mutex_lock(&chip->lock);
827 	ret = lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
828 		     led->brightness);
829 	mutex_unlock(&chip->lock);
830 	return ret;
831 }
832 
833 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
834 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
835 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
836 static LP55XX_DEV_ATTR_RW(engine1_leds, show_engine1_leds, store_engine1_leds);
837 static LP55XX_DEV_ATTR_RW(engine2_leds, show_engine2_leds, store_engine2_leds);
838 static LP55XX_DEV_ATTR_RW(engine3_leds, show_engine3_leds, store_engine3_leds);
839 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
840 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
841 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
842 static LP55XX_DEV_ATTR_RO(selftest, lp5523_selftest);
843 static LP55XX_DEV_ATTR_RW(master_fader1, show_master_fader1,
844 			  store_master_fader1);
845 static LP55XX_DEV_ATTR_RW(master_fader2, show_master_fader2,
846 			  store_master_fader2);
847 static LP55XX_DEV_ATTR_RW(master_fader3, show_master_fader3,
848 			  store_master_fader3);
849 static LP55XX_DEV_ATTR_RW(master_fader_leds, show_master_fader_leds,
850 			  store_master_fader_leds);
851 
852 static struct attribute *lp5523_attributes[] = {
853 	&dev_attr_engine1_mode.attr,
854 	&dev_attr_engine2_mode.attr,
855 	&dev_attr_engine3_mode.attr,
856 	&dev_attr_engine1_load.attr,
857 	&dev_attr_engine2_load.attr,
858 	&dev_attr_engine3_load.attr,
859 	&dev_attr_engine1_leds.attr,
860 	&dev_attr_engine2_leds.attr,
861 	&dev_attr_engine3_leds.attr,
862 	&dev_attr_selftest.attr,
863 	&dev_attr_master_fader1.attr,
864 	&dev_attr_master_fader2.attr,
865 	&dev_attr_master_fader3.attr,
866 	&dev_attr_master_fader_leds.attr,
867 	NULL,
868 };
869 
870 static const struct attribute_group lp5523_group = {
871 	.attrs = lp5523_attributes,
872 };
873 
874 /* Chip specific configurations */
875 static struct lp55xx_device_config lp5523_cfg = {
876 	.reset = {
877 		.addr = LP5523_REG_RESET,
878 		.val  = LP5523_RESET,
879 	},
880 	.enable = {
881 		.addr = LP5523_REG_ENABLE,
882 		.val  = LP5523_ENABLE,
883 	},
884 	.max_channel  = LP5523_MAX_LEDS,
885 	.post_init_device   = lp5523_post_init_device,
886 	.brightness_fn      = lp5523_led_brightness,
887 	.multicolor_brightness_fn = lp5523_multicolor_brightness,
888 	.set_led_current    = lp5523_set_led_current,
889 	.firmware_cb        = lp5523_firmware_loaded,
890 	.run_engine         = lp5523_run_engine,
891 	.dev_attr_group     = &lp5523_group,
892 };
893 
894 static int lp5523_probe(struct i2c_client *client)
895 {
896 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
897 	int ret;
898 	struct lp55xx_chip *chip;
899 	struct lp55xx_led *led;
900 	struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
901 	struct device_node *np = dev_of_node(&client->dev);
902 
903 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
904 	if (!chip)
905 		return -ENOMEM;
906 
907 	chip->cfg = &lp5523_cfg;
908 
909 	if (!pdata) {
910 		if (np) {
911 			pdata = lp55xx_of_populate_pdata(&client->dev, np,
912 							 chip);
913 			if (IS_ERR(pdata))
914 				return PTR_ERR(pdata);
915 		} else {
916 			dev_err(&client->dev, "no platform data\n");
917 			return -EINVAL;
918 		}
919 	}
920 
921 	led = devm_kcalloc(&client->dev,
922 			pdata->num_channels, sizeof(*led), GFP_KERNEL);
923 	if (!led)
924 		return -ENOMEM;
925 
926 	chip->cl = client;
927 	chip->pdata = pdata;
928 
929 	mutex_init(&chip->lock);
930 
931 	i2c_set_clientdata(client, led);
932 
933 	ret = lp55xx_init_device(chip);
934 	if (ret)
935 		goto err_init;
936 
937 	dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
938 
939 	ret = lp55xx_register_leds(led, chip);
940 	if (ret)
941 		goto err_out;
942 
943 	ret = lp55xx_register_sysfs(chip);
944 	if (ret) {
945 		dev_err(&client->dev, "registering sysfs failed\n");
946 		goto err_out;
947 	}
948 
949 	return 0;
950 
951 err_out:
952 	lp55xx_deinit_device(chip);
953 err_init:
954 	return ret;
955 }
956 
957 static void lp5523_remove(struct i2c_client *client)
958 {
959 	struct lp55xx_led *led = i2c_get_clientdata(client);
960 	struct lp55xx_chip *chip = led->chip;
961 
962 	lp5523_stop_all_engines(chip);
963 	lp55xx_unregister_sysfs(chip);
964 	lp55xx_deinit_device(chip);
965 }
966 
967 static const struct i2c_device_id lp5523_id[] = {
968 	{ "lp5523",  LP5523 },
969 	{ "lp55231", LP55231 },
970 	{ }
971 };
972 
973 MODULE_DEVICE_TABLE(i2c, lp5523_id);
974 
975 static const struct of_device_id of_lp5523_leds_match[] = {
976 	{ .compatible = "national,lp5523", },
977 	{ .compatible = "ti,lp55231", },
978 	{},
979 };
980 
981 MODULE_DEVICE_TABLE(of, of_lp5523_leds_match);
982 
983 static struct i2c_driver lp5523_driver = {
984 	.driver = {
985 		.name	= "lp5523x",
986 		.of_match_table = of_lp5523_leds_match,
987 	},
988 	.probe		= lp5523_probe,
989 	.remove		= lp5523_remove,
990 	.id_table	= lp5523_id,
991 };
992 
993 module_i2c_driver(lp5523_driver);
994 
995 MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
996 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
997 MODULE_DESCRIPTION("LP5523 LED engine");
998 MODULE_LICENSE("GPL");
999