xref: /openbmc/linux/drivers/leds/leds-lp5523.c (revision b8d312aa)
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_AUTO			0x18
61 #define LP5523_AUTO_CLK			0x02
62 
63 #define LP5523_EN_LEDTEST		0x80
64 #define LP5523_LEDTEST_DONE		0x80
65 #define LP5523_RESET			0xFF
66 #define LP5523_ADC_SHORTCIRC_LIM	80
67 #define LP5523_EXT_CLK_USED		0x08
68 #define LP5523_ENG_STATUS_MASK		0x07
69 
70 #define LP5523_FADER_MAPPING_MASK	0xC0
71 #define LP5523_FADER_MAPPING_SHIFT	6
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 	static const 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 	static const 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 	static const 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_all_engines(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_stop_engine(struct lp55xx_chip *chip)
196 {
197 	enum lp55xx_engine_index idx = chip->engine_idx;
198 	static const u8 mask[] = {
199 		[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
200 		[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
201 		[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
202 	};
203 
204 	lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], 0);
205 
206 	lp5523_wait_opmode_done();
207 }
208 
209 static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
210 {
211 	int i;
212 
213 	for (i = 0; i < LP5523_MAX_LEDS; i++)
214 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
215 }
216 
217 static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
218 {
219 	int ret;
220 	u8 mode;
221 	u8 exec;
222 
223 	/* stop engine */
224 	if (!start) {
225 		lp5523_stop_engine(chip);
226 		lp5523_turn_off_channels(chip);
227 		return;
228 	}
229 
230 	/*
231 	 * To run the engine,
232 	 * operation mode and enable register should updated at the same time
233 	 */
234 
235 	ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
236 	if (ret)
237 		return;
238 
239 	ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
240 	if (ret)
241 		return;
242 
243 	/* change operation mode to RUN only when each engine is loading */
244 	if (LP5523_ENG1_IS_LOADING(mode)) {
245 		mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
246 		exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
247 	}
248 
249 	if (LP5523_ENG2_IS_LOADING(mode)) {
250 		mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
251 		exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
252 	}
253 
254 	if (LP5523_ENG3_IS_LOADING(mode)) {
255 		mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
256 		exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
257 	}
258 
259 	lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
260 	lp5523_wait_opmode_done();
261 
262 	lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
263 }
264 
265 static int lp5523_init_program_engine(struct lp55xx_chip *chip)
266 {
267 	int i;
268 	int j;
269 	int ret;
270 	u8 status;
271 	/* one pattern per engine setting LED MUX start and stop addresses */
272 	static const u8 pattern[][LP5523_PROGRAM_LENGTH] =  {
273 		{ 0x9c, 0x30, 0x9c, 0xb0, 0x9d, 0x80, 0xd8, 0x00, 0},
274 		{ 0x9c, 0x40, 0x9c, 0xc0, 0x9d, 0x80, 0xd8, 0x00, 0},
275 		{ 0x9c, 0x50, 0x9c, 0xd0, 0x9d, 0x80, 0xd8, 0x00, 0},
276 	};
277 
278 	/* hardcode 32 bytes of memory for each engine from program memory */
279 	ret = lp55xx_write(chip, LP5523_REG_CH1_PROG_START, 0x00);
280 	if (ret)
281 		return ret;
282 
283 	ret = lp55xx_write(chip, LP5523_REG_CH2_PROG_START, 0x10);
284 	if (ret)
285 		return ret;
286 
287 	ret = lp55xx_write(chip, LP5523_REG_CH3_PROG_START, 0x20);
288 	if (ret)
289 		return ret;
290 
291 	/* write LED MUX address space for each engine */
292 	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
293 		chip->engine_idx = i;
294 		lp5523_load_engine_and_select_page(chip);
295 
296 		for (j = 0; j < LP5523_PROGRAM_LENGTH; j++) {
297 			ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + j,
298 					pattern[i - 1][j]);
299 			if (ret)
300 				goto out;
301 		}
302 	}
303 
304 	lp5523_run_engine(chip, true);
305 
306 	/* Let the programs run for couple of ms and check the engine status */
307 	usleep_range(3000, 6000);
308 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
309 	if (ret)
310 		return ret;
311 	status &= LP5523_ENG_STATUS_MASK;
312 
313 	if (status != LP5523_ENG_STATUS_MASK) {
314 		dev_err(&chip->cl->dev,
315 			"could not configure LED engine, status = 0x%.2x\n",
316 			status);
317 		ret = -1;
318 	}
319 
320 out:
321 	lp5523_stop_all_engines(chip);
322 	return ret;
323 }
324 
325 static int lp5523_update_program_memory(struct lp55xx_chip *chip,
326 					const u8 *data, size_t size)
327 {
328 	u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
329 	unsigned cmd;
330 	char c[3];
331 	int nrchars;
332 	int ret;
333 	int offset = 0;
334 	int i = 0;
335 
336 	while ((offset < size - 1) && (i < LP5523_PROGRAM_LENGTH)) {
337 		/* separate sscanfs because length is working only for %s */
338 		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
339 		if (ret != 1)
340 			goto err;
341 
342 		ret = sscanf(c, "%2x", &cmd);
343 		if (ret != 1)
344 			goto err;
345 
346 		pattern[i] = (u8)cmd;
347 		offset += nrchars;
348 		i++;
349 	}
350 
351 	/* Each instruction is 16bit long. Check that length is even */
352 	if (i % 2)
353 		goto err;
354 
355 	for (i = 0; i < LP5523_PROGRAM_LENGTH; i++) {
356 		ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
357 		if (ret)
358 			return -EINVAL;
359 	}
360 
361 	return size;
362 
363 err:
364 	dev_err(&chip->cl->dev, "wrong pattern format\n");
365 	return -EINVAL;
366 }
367 
368 static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
369 {
370 	const struct firmware *fw = chip->fw;
371 
372 	if (fw->size > LP5523_PROGRAM_LENGTH) {
373 		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
374 			fw->size);
375 		return;
376 	}
377 
378 	/*
379 	 * Program memory sequence
380 	 *  1) set engine mode to "LOAD"
381 	 *  2) write firmware data into program memory
382 	 */
383 
384 	lp5523_load_engine_and_select_page(chip);
385 	lp5523_update_program_memory(chip, fw->data, fw->size);
386 }
387 
388 static ssize_t show_engine_mode(struct device *dev,
389 				struct device_attribute *attr,
390 				char *buf, int nr)
391 {
392 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
393 	struct lp55xx_chip *chip = led->chip;
394 	enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
395 
396 	switch (mode) {
397 	case LP55XX_ENGINE_RUN:
398 		return sprintf(buf, "run\n");
399 	case LP55XX_ENGINE_LOAD:
400 		return sprintf(buf, "load\n");
401 	case LP55XX_ENGINE_DISABLED:
402 	default:
403 		return sprintf(buf, "disabled\n");
404 	}
405 }
406 show_mode(1)
407 show_mode(2)
408 show_mode(3)
409 
410 static ssize_t store_engine_mode(struct device *dev,
411 				 struct device_attribute *attr,
412 				 const char *buf, size_t len, int nr)
413 {
414 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
415 	struct lp55xx_chip *chip = led->chip;
416 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
417 
418 	mutex_lock(&chip->lock);
419 
420 	chip->engine_idx = nr;
421 
422 	if (!strncmp(buf, "run", 3)) {
423 		lp5523_run_engine(chip, true);
424 		engine->mode = LP55XX_ENGINE_RUN;
425 	} else if (!strncmp(buf, "load", 4)) {
426 		lp5523_stop_engine(chip);
427 		lp5523_load_engine(chip);
428 		engine->mode = LP55XX_ENGINE_LOAD;
429 	} else if (!strncmp(buf, "disabled", 8)) {
430 		lp5523_stop_engine(chip);
431 		engine->mode = LP55XX_ENGINE_DISABLED;
432 	}
433 
434 	mutex_unlock(&chip->lock);
435 
436 	return len;
437 }
438 store_mode(1)
439 store_mode(2)
440 store_mode(3)
441 
442 static int lp5523_mux_parse(const char *buf, u16 *mux, size_t len)
443 {
444 	u16 tmp_mux = 0;
445 	int i;
446 
447 	len = min_t(int, len, LP5523_MAX_LEDS);
448 
449 	for (i = 0; i < len; i++) {
450 		switch (buf[i]) {
451 		case '1':
452 			tmp_mux |= (1 << i);
453 			break;
454 		case '0':
455 			break;
456 		case '\n':
457 			i = len;
458 			break;
459 		default:
460 			return -1;
461 		}
462 	}
463 	*mux = tmp_mux;
464 
465 	return 0;
466 }
467 
468 static void lp5523_mux_to_array(u16 led_mux, char *array)
469 {
470 	int i, pos = 0;
471 	for (i = 0; i < LP5523_MAX_LEDS; i++)
472 		pos += sprintf(array + pos, "%x", LED_ACTIVE(led_mux, i));
473 
474 	array[pos] = '\0';
475 }
476 
477 static ssize_t show_engine_leds(struct device *dev,
478 			    struct device_attribute *attr,
479 			    char *buf, int nr)
480 {
481 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
482 	struct lp55xx_chip *chip = led->chip;
483 	char mux[LP5523_MAX_LEDS + 1];
484 
485 	lp5523_mux_to_array(chip->engines[nr - 1].led_mux, mux);
486 
487 	return sprintf(buf, "%s\n", mux);
488 }
489 show_leds(1)
490 show_leds(2)
491 show_leds(3)
492 
493 static int lp5523_load_mux(struct lp55xx_chip *chip, u16 mux, int nr)
494 {
495 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
496 	int ret;
497 	static const u8 mux_page[] = {
498 		[LP55XX_ENGINE_1] = LP5523_PAGE_MUX1,
499 		[LP55XX_ENGINE_2] = LP5523_PAGE_MUX2,
500 		[LP55XX_ENGINE_3] = LP5523_PAGE_MUX3,
501 	};
502 
503 	lp5523_load_engine(chip);
504 
505 	ret = lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, mux_page[nr]);
506 	if (ret)
507 		return ret;
508 
509 	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM , (u8)(mux >> 8));
510 	if (ret)
511 		return ret;
512 
513 	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + 1, (u8)(mux));
514 	if (ret)
515 		return ret;
516 
517 	engine->led_mux = mux;
518 	return 0;
519 }
520 
521 static ssize_t store_engine_leds(struct device *dev,
522 			     struct device_attribute *attr,
523 			     const char *buf, size_t len, int nr)
524 {
525 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
526 	struct lp55xx_chip *chip = led->chip;
527 	struct lp55xx_engine *engine = &chip->engines[nr - 1];
528 	u16 mux = 0;
529 	ssize_t ret;
530 
531 	if (lp5523_mux_parse(buf, &mux, len))
532 		return -EINVAL;
533 
534 	mutex_lock(&chip->lock);
535 
536 	chip->engine_idx = nr;
537 	ret = -EINVAL;
538 
539 	if (engine->mode != LP55XX_ENGINE_LOAD)
540 		goto leave;
541 
542 	if (lp5523_load_mux(chip, mux, nr))
543 		goto leave;
544 
545 	ret = len;
546 leave:
547 	mutex_unlock(&chip->lock);
548 	return ret;
549 }
550 store_leds(1)
551 store_leds(2)
552 store_leds(3)
553 
554 static ssize_t store_engine_load(struct device *dev,
555 			     struct device_attribute *attr,
556 			     const char *buf, size_t len, int nr)
557 {
558 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
559 	struct lp55xx_chip *chip = led->chip;
560 	int ret;
561 
562 	mutex_lock(&chip->lock);
563 
564 	chip->engine_idx = nr;
565 	lp5523_load_engine_and_select_page(chip);
566 	ret = lp5523_update_program_memory(chip, buf, len);
567 
568 	mutex_unlock(&chip->lock);
569 
570 	return ret;
571 }
572 store_load(1)
573 store_load(2)
574 store_load(3)
575 
576 static ssize_t lp5523_selftest(struct device *dev,
577 			       struct device_attribute *attr,
578 			       char *buf)
579 {
580 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
581 	struct lp55xx_chip *chip = led->chip;
582 	struct lp55xx_platform_data *pdata = chip->pdata;
583 	int i, ret, pos = 0;
584 	u8 status, adc, vdd;
585 
586 	mutex_lock(&chip->lock);
587 
588 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
589 	if (ret < 0)
590 		goto fail;
591 
592 	/* Check that ext clock is really in use if requested */
593 	if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
594 		if  ((status & LP5523_EXT_CLK_USED) == 0)
595 			goto fail;
596 	}
597 
598 	/* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
599 	lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
600 	usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
601 	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
602 	if (ret < 0)
603 		goto fail;
604 
605 	if (!(status & LP5523_LEDTEST_DONE))
606 		usleep_range(3000, 6000); /* Was not ready. Wait little bit */
607 
608 	ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
609 	if (ret < 0)
610 		goto fail;
611 
612 	vdd--;	/* There may be some fluctuation in measurement */
613 
614 	for (i = 0; i < LP5523_MAX_LEDS; i++) {
615 		/* Skip non-existing channels */
616 		if (pdata->led_config[i].led_current == 0)
617 			continue;
618 
619 		/* Set default current */
620 		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
621 			pdata->led_config[i].led_current);
622 
623 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff);
624 		/* let current stabilize 2 - 4ms before measurements start */
625 		usleep_range(2000, 4000);
626 		lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL,
627 			     LP5523_EN_LEDTEST | i);
628 		/* ADC conversion time is 2.7 ms typically */
629 		usleep_range(3000, 6000);
630 		ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
631 		if (ret < 0)
632 			goto fail;
633 
634 		if (!(status & LP5523_LEDTEST_DONE))
635 			usleep_range(3000, 6000);/* Was not ready. Wait. */
636 
637 		ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc);
638 		if (ret < 0)
639 			goto fail;
640 
641 		if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
642 			pos += sprintf(buf + pos, "LED %d FAIL\n", i);
643 
644 		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00);
645 
646 		/* Restore current */
647 		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
648 			led->led_current);
649 		led++;
650 	}
651 	if (pos == 0)
652 		pos = sprintf(buf, "OK\n");
653 	goto release_lock;
654 fail:
655 	pos = sprintf(buf, "FAIL\n");
656 
657 release_lock:
658 	mutex_unlock(&chip->lock);
659 
660 	return pos;
661 }
662 
663 #define show_fader(nr)						\
664 static ssize_t show_master_fader##nr(struct device *dev,	\
665 			    struct device_attribute *attr,	\
666 			    char *buf)				\
667 {								\
668 	return show_master_fader(dev, attr, buf, nr);		\
669 }
670 
671 #define store_fader(nr)						\
672 static ssize_t store_master_fader##nr(struct device *dev,	\
673 			     struct device_attribute *attr,	\
674 			     const char *buf, size_t len)	\
675 {								\
676 	return store_master_fader(dev, attr, buf, len, nr);	\
677 }
678 
679 static ssize_t show_master_fader(struct device *dev,
680 				 struct device_attribute *attr,
681 				 char *buf, int nr)
682 {
683 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
684 	struct lp55xx_chip *chip = led->chip;
685 	int ret;
686 	u8 val;
687 
688 	mutex_lock(&chip->lock);
689 	ret = lp55xx_read(chip, LP5523_REG_MASTER_FADER_BASE + nr - 1, &val);
690 	mutex_unlock(&chip->lock);
691 
692 	if (ret == 0)
693 		ret = sprintf(buf, "%u\n", val);
694 
695 	return ret;
696 }
697 show_fader(1)
698 show_fader(2)
699 show_fader(3)
700 
701 static ssize_t store_master_fader(struct device *dev,
702 				  struct device_attribute *attr,
703 				  const char *buf, size_t len, int nr)
704 {
705 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
706 	struct lp55xx_chip *chip = led->chip;
707 	int ret;
708 	unsigned long val;
709 
710 	if (kstrtoul(buf, 0, &val))
711 		return -EINVAL;
712 
713 	if (val > 0xff)
714 		return -EINVAL;
715 
716 	mutex_lock(&chip->lock);
717 	ret = lp55xx_write(chip, LP5523_REG_MASTER_FADER_BASE + nr - 1,
718 			   (u8)val);
719 	mutex_unlock(&chip->lock);
720 
721 	if (ret == 0)
722 		ret = len;
723 
724 	return ret;
725 }
726 store_fader(1)
727 store_fader(2)
728 store_fader(3)
729 
730 static ssize_t show_master_fader_leds(struct device *dev,
731 				      struct device_attribute *attr,
732 				      char *buf)
733 {
734 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
735 	struct lp55xx_chip *chip = led->chip;
736 	int i, ret, pos = 0;
737 	u8 val;
738 
739 	mutex_lock(&chip->lock);
740 
741 	for (i = 0; i < LP5523_MAX_LEDS; i++) {
742 		ret = lp55xx_read(chip, LP5523_REG_LED_CTRL_BASE + i, &val);
743 		if (ret)
744 			goto leave;
745 
746 		val = (val & LP5523_FADER_MAPPING_MASK)
747 			>> LP5523_FADER_MAPPING_SHIFT;
748 		if (val > 3) {
749 			ret = -EINVAL;
750 			goto leave;
751 		}
752 		buf[pos++] = val + '0';
753 	}
754 	buf[pos++] = '\n';
755 	ret = pos;
756 leave:
757 	mutex_unlock(&chip->lock);
758 	return ret;
759 }
760 
761 static ssize_t store_master_fader_leds(struct device *dev,
762 				       struct device_attribute *attr,
763 				       const char *buf, size_t len)
764 {
765 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
766 	struct lp55xx_chip *chip = led->chip;
767 	int i, n, ret;
768 	u8 val;
769 
770 	n = min_t(int, len, LP5523_MAX_LEDS);
771 
772 	mutex_lock(&chip->lock);
773 
774 	for (i = 0; i < n; i++) {
775 		if (buf[i] >= '0' && buf[i] <= '3') {
776 			val = (buf[i] - '0') << LP5523_FADER_MAPPING_SHIFT;
777 			ret = lp55xx_update_bits(chip,
778 						 LP5523_REG_LED_CTRL_BASE + i,
779 						 LP5523_FADER_MAPPING_MASK,
780 						 val);
781 			if (ret)
782 				goto leave;
783 		} else {
784 			ret = -EINVAL;
785 			goto leave;
786 		}
787 	}
788 	ret = len;
789 leave:
790 	mutex_unlock(&chip->lock);
791 	return ret;
792 }
793 
794 static int lp5523_led_brightness(struct lp55xx_led *led)
795 {
796 	struct lp55xx_chip *chip = led->chip;
797 	int ret;
798 
799 	mutex_lock(&chip->lock);
800 	ret = lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
801 		     led->brightness);
802 	mutex_unlock(&chip->lock);
803 	return ret;
804 }
805 
806 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
807 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
808 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
809 static LP55XX_DEV_ATTR_RW(engine1_leds, show_engine1_leds, store_engine1_leds);
810 static LP55XX_DEV_ATTR_RW(engine2_leds, show_engine2_leds, store_engine2_leds);
811 static LP55XX_DEV_ATTR_RW(engine3_leds, show_engine3_leds, store_engine3_leds);
812 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
813 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
814 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
815 static LP55XX_DEV_ATTR_RO(selftest, lp5523_selftest);
816 static LP55XX_DEV_ATTR_RW(master_fader1, show_master_fader1,
817 			  store_master_fader1);
818 static LP55XX_DEV_ATTR_RW(master_fader2, show_master_fader2,
819 			  store_master_fader2);
820 static LP55XX_DEV_ATTR_RW(master_fader3, show_master_fader3,
821 			  store_master_fader3);
822 static LP55XX_DEV_ATTR_RW(master_fader_leds, show_master_fader_leds,
823 			  store_master_fader_leds);
824 
825 static struct attribute *lp5523_attributes[] = {
826 	&dev_attr_engine1_mode.attr,
827 	&dev_attr_engine2_mode.attr,
828 	&dev_attr_engine3_mode.attr,
829 	&dev_attr_engine1_load.attr,
830 	&dev_attr_engine2_load.attr,
831 	&dev_attr_engine3_load.attr,
832 	&dev_attr_engine1_leds.attr,
833 	&dev_attr_engine2_leds.attr,
834 	&dev_attr_engine3_leds.attr,
835 	&dev_attr_selftest.attr,
836 	&dev_attr_master_fader1.attr,
837 	&dev_attr_master_fader2.attr,
838 	&dev_attr_master_fader3.attr,
839 	&dev_attr_master_fader_leds.attr,
840 	NULL,
841 };
842 
843 static const struct attribute_group lp5523_group = {
844 	.attrs = lp5523_attributes,
845 };
846 
847 /* Chip specific configurations */
848 static struct lp55xx_device_config lp5523_cfg = {
849 	.reset = {
850 		.addr = LP5523_REG_RESET,
851 		.val  = LP5523_RESET,
852 	},
853 	.enable = {
854 		.addr = LP5523_REG_ENABLE,
855 		.val  = LP5523_ENABLE,
856 	},
857 	.max_channel  = LP5523_MAX_LEDS,
858 	.post_init_device   = lp5523_post_init_device,
859 	.brightness_fn      = lp5523_led_brightness,
860 	.set_led_current    = lp5523_set_led_current,
861 	.firmware_cb        = lp5523_firmware_loaded,
862 	.run_engine         = lp5523_run_engine,
863 	.dev_attr_group     = &lp5523_group,
864 };
865 
866 static int lp5523_probe(struct i2c_client *client,
867 			const struct i2c_device_id *id)
868 {
869 	int ret;
870 	struct lp55xx_chip *chip;
871 	struct lp55xx_led *led;
872 	struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
873 	struct device_node *np = client->dev.of_node;
874 
875 	if (!pdata) {
876 		if (np) {
877 			pdata = lp55xx_of_populate_pdata(&client->dev, np);
878 			if (IS_ERR(pdata))
879 				return PTR_ERR(pdata);
880 		} else {
881 			dev_err(&client->dev, "no platform data\n");
882 			return -EINVAL;
883 		}
884 	}
885 
886 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
887 	if (!chip)
888 		return -ENOMEM;
889 
890 	led = devm_kcalloc(&client->dev,
891 			pdata->num_channels, sizeof(*led), GFP_KERNEL);
892 	if (!led)
893 		return -ENOMEM;
894 
895 	chip->cl = client;
896 	chip->pdata = pdata;
897 	chip->cfg = &lp5523_cfg;
898 
899 	mutex_init(&chip->lock);
900 
901 	i2c_set_clientdata(client, led);
902 
903 	ret = lp55xx_init_device(chip);
904 	if (ret)
905 		goto err_init;
906 
907 	dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
908 
909 	ret = lp55xx_register_leds(led, chip);
910 	if (ret)
911 		goto err_register_leds;
912 
913 	ret = lp55xx_register_sysfs(chip);
914 	if (ret) {
915 		dev_err(&client->dev, "registering sysfs failed\n");
916 		goto err_register_sysfs;
917 	}
918 
919 	return 0;
920 
921 err_register_sysfs:
922 	lp55xx_unregister_leds(led, chip);
923 err_register_leds:
924 	lp55xx_deinit_device(chip);
925 err_init:
926 	return ret;
927 }
928 
929 static int lp5523_remove(struct i2c_client *client)
930 {
931 	struct lp55xx_led *led = i2c_get_clientdata(client);
932 	struct lp55xx_chip *chip = led->chip;
933 
934 	lp5523_stop_all_engines(chip);
935 	lp55xx_unregister_sysfs(chip);
936 	lp55xx_unregister_leds(led, chip);
937 	lp55xx_deinit_device(chip);
938 
939 	return 0;
940 }
941 
942 static const struct i2c_device_id lp5523_id[] = {
943 	{ "lp5523",  LP5523 },
944 	{ "lp55231", LP55231 },
945 	{ }
946 };
947 
948 MODULE_DEVICE_TABLE(i2c, lp5523_id);
949 
950 #ifdef CONFIG_OF
951 static const struct of_device_id of_lp5523_leds_match[] = {
952 	{ .compatible = "national,lp5523", },
953 	{ .compatible = "ti,lp55231", },
954 	{},
955 };
956 
957 MODULE_DEVICE_TABLE(of, of_lp5523_leds_match);
958 #endif
959 
960 static struct i2c_driver lp5523_driver = {
961 	.driver = {
962 		.name	= "lp5523x",
963 		.of_match_table = of_match_ptr(of_lp5523_leds_match),
964 	},
965 	.probe		= lp5523_probe,
966 	.remove		= lp5523_remove,
967 	.id_table	= lp5523_id,
968 };
969 
970 module_i2c_driver(lp5523_driver);
971 
972 MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
973 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
974 MODULE_DESCRIPTION("LP5523 LED engine");
975 MODULE_LICENSE("GPL");
976