xref: /openbmc/linux/drivers/leds/leds-lp5562.c (revision 275876e2)
1 /*
2  * LP5562 LED driver
3  *
4  * Copyright (C) 2013 Texas Instruments
5  *
6  * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/delay.h>
14 #include <linux/firmware.h>
15 #include <linux/i2c.h>
16 #include <linux/leds.h>
17 #include <linux/module.h>
18 #include <linux/mutex.h>
19 #include <linux/of.h>
20 #include <linux/platform_data/leds-lp55xx.h>
21 #include <linux/slab.h>
22 
23 #include "leds-lp55xx-common.h"
24 
25 #define LP5562_PROGRAM_LENGTH		32
26 #define LP5562_MAX_LEDS			4
27 
28 /* ENABLE Register 00h */
29 #define LP5562_REG_ENABLE		0x00
30 #define LP5562_EXEC_ENG1_M		0x30
31 #define LP5562_EXEC_ENG2_M		0x0C
32 #define LP5562_EXEC_ENG3_M		0x03
33 #define LP5562_EXEC_M			0x3F
34 #define LP5562_MASTER_ENABLE		0x40	/* Chip master enable */
35 #define LP5562_LOGARITHMIC_PWM		0x80	/* Logarithmic PWM adjustment */
36 #define LP5562_EXEC_RUN			0x2A
37 #define LP5562_ENABLE_DEFAULT	\
38 	(LP5562_MASTER_ENABLE | LP5562_LOGARITHMIC_PWM)
39 #define LP5562_ENABLE_RUN_PROGRAM	\
40 	(LP5562_ENABLE_DEFAULT | LP5562_EXEC_RUN)
41 
42 /* OPMODE Register 01h */
43 #define LP5562_REG_OP_MODE		0x01
44 #define LP5562_MODE_ENG1_M		0x30
45 #define LP5562_MODE_ENG2_M		0x0C
46 #define LP5562_MODE_ENG3_M		0x03
47 #define LP5562_LOAD_ENG1		0x10
48 #define LP5562_LOAD_ENG2		0x04
49 #define LP5562_LOAD_ENG3		0x01
50 #define LP5562_RUN_ENG1			0x20
51 #define LP5562_RUN_ENG2			0x08
52 #define LP5562_RUN_ENG3			0x02
53 #define LP5562_ENG1_IS_LOADING(mode)	\
54 	((mode & LP5562_MODE_ENG1_M) == LP5562_LOAD_ENG1)
55 #define LP5562_ENG2_IS_LOADING(mode)	\
56 	((mode & LP5562_MODE_ENG2_M) == LP5562_LOAD_ENG2)
57 #define LP5562_ENG3_IS_LOADING(mode)	\
58 	((mode & LP5562_MODE_ENG3_M) == LP5562_LOAD_ENG3)
59 
60 /* BRIGHTNESS Registers */
61 #define LP5562_REG_R_PWM		0x04
62 #define LP5562_REG_G_PWM		0x03
63 #define LP5562_REG_B_PWM		0x02
64 #define LP5562_REG_W_PWM		0x0E
65 
66 /* CURRENT Registers */
67 #define LP5562_REG_R_CURRENT		0x07
68 #define LP5562_REG_G_CURRENT		0x06
69 #define LP5562_REG_B_CURRENT		0x05
70 #define LP5562_REG_W_CURRENT		0x0F
71 
72 /* CONFIG Register 08h */
73 #define LP5562_REG_CONFIG		0x08
74 #define LP5562_PWM_HF			0x40
75 #define LP5562_PWRSAVE_EN		0x20
76 #define LP5562_CLK_INT			0x01	/* Internal clock */
77 #define LP5562_DEFAULT_CFG		(LP5562_PWM_HF | LP5562_PWRSAVE_EN)
78 
79 /* RESET Register 0Dh */
80 #define LP5562_REG_RESET		0x0D
81 #define LP5562_RESET			0xFF
82 
83 /* PROGRAM ENGINE Registers */
84 #define LP5562_REG_PROG_MEM_ENG1	0x10
85 #define LP5562_REG_PROG_MEM_ENG2	0x30
86 #define LP5562_REG_PROG_MEM_ENG3	0x50
87 
88 /* LEDMAP Register 70h */
89 #define LP5562_REG_ENG_SEL		0x70
90 #define LP5562_ENG_SEL_PWM		0
91 #define LP5562_ENG_FOR_RGB_M		0x3F
92 #define LP5562_ENG_SEL_RGB		0x1B	/* R:ENG1, G:ENG2, B:ENG3 */
93 #define LP5562_ENG_FOR_W_M		0xC0
94 #define LP5562_ENG1_FOR_W		0x40	/* W:ENG1 */
95 #define LP5562_ENG2_FOR_W		0x80	/* W:ENG2 */
96 #define LP5562_ENG3_FOR_W		0xC0	/* W:ENG3 */
97 
98 /* Program Commands */
99 #define LP5562_CMD_DISABLE		0x00
100 #define LP5562_CMD_LOAD			0x15
101 #define LP5562_CMD_RUN			0x2A
102 #define LP5562_CMD_DIRECT		0x3F
103 #define LP5562_PATTERN_OFF		0
104 
105 static inline void lp5562_wait_opmode_done(void)
106 {
107 	/* operation mode change needs to be longer than 153 us */
108 	usleep_range(200, 300);
109 }
110 
111 static inline void lp5562_wait_enable_done(void)
112 {
113 	/* it takes more 488 us to update ENABLE register */
114 	usleep_range(500, 600);
115 }
116 
117 static void lp5562_set_led_current(struct lp55xx_led *led, u8 led_current)
118 {
119 	u8 addr[] = {
120 		LP5562_REG_R_CURRENT,
121 		LP5562_REG_G_CURRENT,
122 		LP5562_REG_B_CURRENT,
123 		LP5562_REG_W_CURRENT,
124 	};
125 
126 	led->led_current = led_current;
127 	lp55xx_write(led->chip, addr[led->chan_nr], led_current);
128 }
129 
130 static void lp5562_load_engine(struct lp55xx_chip *chip)
131 {
132 	enum lp55xx_engine_index idx = chip->engine_idx;
133 	u8 mask[] = {
134 		[LP55XX_ENGINE_1] = LP5562_MODE_ENG1_M,
135 		[LP55XX_ENGINE_2] = LP5562_MODE_ENG2_M,
136 		[LP55XX_ENGINE_3] = LP5562_MODE_ENG3_M,
137 	};
138 
139 	u8 val[] = {
140 		[LP55XX_ENGINE_1] = LP5562_LOAD_ENG1,
141 		[LP55XX_ENGINE_2] = LP5562_LOAD_ENG2,
142 		[LP55XX_ENGINE_3] = LP5562_LOAD_ENG3,
143 	};
144 
145 	lp55xx_update_bits(chip, LP5562_REG_OP_MODE, mask[idx], val[idx]);
146 
147 	lp5562_wait_opmode_done();
148 }
149 
150 static void lp5562_stop_engine(struct lp55xx_chip *chip)
151 {
152 	lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DISABLE);
153 	lp5562_wait_opmode_done();
154 }
155 
156 static void lp5562_run_engine(struct lp55xx_chip *chip, bool start)
157 {
158 	int ret;
159 	u8 mode;
160 	u8 exec;
161 
162 	/* stop engine */
163 	if (!start) {
164 		lp55xx_write(chip, LP5562_REG_ENABLE, LP5562_ENABLE_DEFAULT);
165 		lp5562_wait_enable_done();
166 		lp5562_stop_engine(chip);
167 		lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
168 		lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
169 		lp5562_wait_opmode_done();
170 		return;
171 	}
172 
173 	/*
174 	 * To run the engine,
175 	 * operation mode and enable register should updated at the same time
176 	 */
177 
178 	ret = lp55xx_read(chip, LP5562_REG_OP_MODE, &mode);
179 	if (ret)
180 		return;
181 
182 	ret = lp55xx_read(chip, LP5562_REG_ENABLE, &exec);
183 	if (ret)
184 		return;
185 
186 	/* change operation mode to RUN only when each engine is loading */
187 	if (LP5562_ENG1_IS_LOADING(mode)) {
188 		mode = (mode & ~LP5562_MODE_ENG1_M) | LP5562_RUN_ENG1;
189 		exec = (exec & ~LP5562_EXEC_ENG1_M) | LP5562_RUN_ENG1;
190 	}
191 
192 	if (LP5562_ENG2_IS_LOADING(mode)) {
193 		mode = (mode & ~LP5562_MODE_ENG2_M) | LP5562_RUN_ENG2;
194 		exec = (exec & ~LP5562_EXEC_ENG2_M) | LP5562_RUN_ENG2;
195 	}
196 
197 	if (LP5562_ENG3_IS_LOADING(mode)) {
198 		mode = (mode & ~LP5562_MODE_ENG3_M) | LP5562_RUN_ENG3;
199 		exec = (exec & ~LP5562_EXEC_ENG3_M) | LP5562_RUN_ENG3;
200 	}
201 
202 	lp55xx_write(chip, LP5562_REG_OP_MODE, mode);
203 	lp5562_wait_opmode_done();
204 
205 	lp55xx_update_bits(chip, LP5562_REG_ENABLE, LP5562_EXEC_M, exec);
206 	lp5562_wait_enable_done();
207 }
208 
209 static int lp5562_update_firmware(struct lp55xx_chip *chip,
210 					const u8 *data, size_t size)
211 {
212 	enum lp55xx_engine_index idx = chip->engine_idx;
213 	u8 pattern[LP5562_PROGRAM_LENGTH] = {0};
214 	u8 addr[] = {
215 		[LP55XX_ENGINE_1] = LP5562_REG_PROG_MEM_ENG1,
216 		[LP55XX_ENGINE_2] = LP5562_REG_PROG_MEM_ENG2,
217 		[LP55XX_ENGINE_3] = LP5562_REG_PROG_MEM_ENG3,
218 	};
219 	unsigned cmd;
220 	char c[3];
221 	int program_size;
222 	int nrchars;
223 	int offset = 0;
224 	int ret;
225 	int i;
226 
227 	/* clear program memory before updating */
228 	for (i = 0; i < LP5562_PROGRAM_LENGTH; i++)
229 		lp55xx_write(chip, addr[idx] + i, 0);
230 
231 	i = 0;
232 	while ((offset < size - 1) && (i < LP5562_PROGRAM_LENGTH)) {
233 		/* separate sscanfs because length is working only for %s */
234 		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
235 		if (ret != 1)
236 			goto err;
237 
238 		ret = sscanf(c, "%2x", &cmd);
239 		if (ret != 1)
240 			goto err;
241 
242 		pattern[i] = (u8)cmd;
243 		offset += nrchars;
244 		i++;
245 	}
246 
247 	/* Each instruction is 16bit long. Check that length is even */
248 	if (i % 2)
249 		goto err;
250 
251 	program_size = i;
252 	for (i = 0; i < program_size; i++)
253 		lp55xx_write(chip, addr[idx] + i, pattern[i]);
254 
255 	return 0;
256 
257 err:
258 	dev_err(&chip->cl->dev, "wrong pattern format\n");
259 	return -EINVAL;
260 }
261 
262 static void lp5562_firmware_loaded(struct lp55xx_chip *chip)
263 {
264 	const struct firmware *fw = chip->fw;
265 
266 	if (fw->size > LP5562_PROGRAM_LENGTH) {
267 		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
268 			fw->size);
269 		return;
270 	}
271 
272 	/*
273 	 * Program momery sequence
274 	 *  1) set engine mode to "LOAD"
275 	 *  2) write firmware data into program memory
276 	 */
277 
278 	lp5562_load_engine(chip);
279 	lp5562_update_firmware(chip, fw->data, fw->size);
280 }
281 
282 static int lp5562_post_init_device(struct lp55xx_chip *chip)
283 {
284 	int ret;
285 	u8 cfg = LP5562_DEFAULT_CFG;
286 
287 	/* Set all PWMs to direct control mode */
288 	ret = lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
289 	if (ret)
290 		return ret;
291 
292 	lp5562_wait_opmode_done();
293 
294 	/* Update configuration for the clock setting */
295 	if (!lp55xx_is_extclk_used(chip))
296 		cfg |= LP5562_CLK_INT;
297 
298 	ret = lp55xx_write(chip, LP5562_REG_CONFIG, cfg);
299 	if (ret)
300 		return ret;
301 
302 	/* Initialize all channels PWM to zero -> leds off */
303 	lp55xx_write(chip, LP5562_REG_R_PWM, 0);
304 	lp55xx_write(chip, LP5562_REG_G_PWM, 0);
305 	lp55xx_write(chip, LP5562_REG_B_PWM, 0);
306 	lp55xx_write(chip, LP5562_REG_W_PWM, 0);
307 
308 	/* Set LED map as register PWM by default */
309 	lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
310 
311 	return 0;
312 }
313 
314 static void lp5562_led_brightness_work(struct work_struct *work)
315 {
316 	struct lp55xx_led *led = container_of(work, struct lp55xx_led,
317 					      brightness_work);
318 	struct lp55xx_chip *chip = led->chip;
319 	u8 addr[] = {
320 		LP5562_REG_R_PWM,
321 		LP5562_REG_G_PWM,
322 		LP5562_REG_B_PWM,
323 		LP5562_REG_W_PWM,
324 	};
325 
326 	mutex_lock(&chip->lock);
327 	lp55xx_write(chip, addr[led->chan_nr], led->brightness);
328 	mutex_unlock(&chip->lock);
329 }
330 
331 static void lp5562_write_program_memory(struct lp55xx_chip *chip,
332 					u8 base, const u8 *rgb, int size)
333 {
334 	int i;
335 
336 	if (!rgb || size <= 0)
337 		return;
338 
339 	for (i = 0; i < size; i++)
340 		lp55xx_write(chip, base + i, *(rgb + i));
341 
342 	lp55xx_write(chip, base + i, 0);
343 	lp55xx_write(chip, base + i + 1, 0);
344 }
345 
346 /* check the size of program count */
347 static inline bool _is_pc_overflow(struct lp55xx_predef_pattern *ptn)
348 {
349 	return ptn->size_r >= LP5562_PROGRAM_LENGTH ||
350 	       ptn->size_g >= LP5562_PROGRAM_LENGTH ||
351 	       ptn->size_b >= LP5562_PROGRAM_LENGTH;
352 }
353 
354 static int lp5562_run_predef_led_pattern(struct lp55xx_chip *chip, int mode)
355 {
356 	struct lp55xx_predef_pattern *ptn;
357 	int i;
358 
359 	if (mode == LP5562_PATTERN_OFF) {
360 		lp5562_run_engine(chip, false);
361 		return 0;
362 	}
363 
364 	ptn = chip->pdata->patterns + (mode - 1);
365 	if (!ptn || _is_pc_overflow(ptn)) {
366 		dev_err(&chip->cl->dev, "invalid pattern data\n");
367 		return -EINVAL;
368 	}
369 
370 	lp5562_stop_engine(chip);
371 
372 	/* Set LED map as RGB */
373 	lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_RGB);
374 
375 	/* Load engines */
376 	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
377 		chip->engine_idx = i;
378 		lp5562_load_engine(chip);
379 	}
380 
381 	/* Clear program registers */
382 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1, 0);
383 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1 + 1, 0);
384 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2, 0);
385 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2 + 1, 0);
386 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3, 0);
387 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3 + 1, 0);
388 
389 	/* Program engines */
390 	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG1,
391 				ptn->r, ptn->size_r);
392 	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG2,
393 				ptn->g, ptn->size_g);
394 	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG3,
395 				ptn->b, ptn->size_b);
396 
397 	/* Run engines */
398 	lp5562_run_engine(chip, true);
399 
400 	return 0;
401 }
402 
403 static ssize_t lp5562_store_pattern(struct device *dev,
404 				struct device_attribute *attr,
405 				const char *buf, size_t len)
406 {
407 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
408 	struct lp55xx_chip *chip = led->chip;
409 	struct lp55xx_predef_pattern *ptn = chip->pdata->patterns;
410 	int num_patterns = chip->pdata->num_patterns;
411 	unsigned long mode;
412 	int ret;
413 
414 	ret = kstrtoul(buf, 0, &mode);
415 	if (ret)
416 		return ret;
417 
418 	if (mode > num_patterns || !ptn)
419 		return -EINVAL;
420 
421 	mutex_lock(&chip->lock);
422 	ret = lp5562_run_predef_led_pattern(chip, mode);
423 	mutex_unlock(&chip->lock);
424 
425 	if (ret)
426 		return ret;
427 
428 	return len;
429 }
430 
431 static ssize_t lp5562_store_engine_mux(struct device *dev,
432 				     struct device_attribute *attr,
433 				     const char *buf, size_t len)
434 {
435 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
436 	struct lp55xx_chip *chip = led->chip;
437 	u8 mask;
438 	u8 val;
439 
440 	/* LED map
441 	 * R ... Engine 1 (fixed)
442 	 * G ... Engine 2 (fixed)
443 	 * B ... Engine 3 (fixed)
444 	 * W ... Engine 1 or 2 or 3
445 	 */
446 
447 	if (sysfs_streq(buf, "RGB")) {
448 		mask = LP5562_ENG_FOR_RGB_M;
449 		val = LP5562_ENG_SEL_RGB;
450 	} else if (sysfs_streq(buf, "W")) {
451 		enum lp55xx_engine_index idx = chip->engine_idx;
452 
453 		mask = LP5562_ENG_FOR_W_M;
454 		switch (idx) {
455 		case LP55XX_ENGINE_1:
456 			val = LP5562_ENG1_FOR_W;
457 			break;
458 		case LP55XX_ENGINE_2:
459 			val = LP5562_ENG2_FOR_W;
460 			break;
461 		case LP55XX_ENGINE_3:
462 			val = LP5562_ENG3_FOR_W;
463 			break;
464 		default:
465 			return -EINVAL;
466 		}
467 
468 	} else {
469 		dev_err(dev, "choose RGB or W\n");
470 		return -EINVAL;
471 	}
472 
473 	mutex_lock(&chip->lock);
474 	lp55xx_update_bits(chip, LP5562_REG_ENG_SEL, mask, val);
475 	mutex_unlock(&chip->lock);
476 
477 	return len;
478 }
479 
480 static LP55XX_DEV_ATTR_WO(led_pattern, lp5562_store_pattern);
481 static LP55XX_DEV_ATTR_WO(engine_mux, lp5562_store_engine_mux);
482 
483 static struct attribute *lp5562_attributes[] = {
484 	&dev_attr_led_pattern.attr,
485 	&dev_attr_engine_mux.attr,
486 	NULL,
487 };
488 
489 static const struct attribute_group lp5562_group = {
490 	.attrs = lp5562_attributes,
491 };
492 
493 /* Chip specific configurations */
494 static struct lp55xx_device_config lp5562_cfg = {
495 	.max_channel  = LP5562_MAX_LEDS,
496 	.reset = {
497 		.addr = LP5562_REG_RESET,
498 		.val  = LP5562_RESET,
499 	},
500 	.enable = {
501 		.addr = LP5562_REG_ENABLE,
502 		.val  = LP5562_ENABLE_DEFAULT,
503 	},
504 	.post_init_device   = lp5562_post_init_device,
505 	.set_led_current    = lp5562_set_led_current,
506 	.brightness_work_fn = lp5562_led_brightness_work,
507 	.run_engine         = lp5562_run_engine,
508 	.firmware_cb        = lp5562_firmware_loaded,
509 	.dev_attr_group     = &lp5562_group,
510 };
511 
512 static int lp5562_probe(struct i2c_client *client,
513 			const struct i2c_device_id *id)
514 {
515 	int ret;
516 	struct lp55xx_chip *chip;
517 	struct lp55xx_led *led;
518 	struct lp55xx_platform_data *pdata;
519 	struct device_node *np = client->dev.of_node;
520 
521 	if (!dev_get_platdata(&client->dev)) {
522 		if (np) {
523 			ret = lp55xx_of_populate_pdata(&client->dev, np);
524 			if (ret < 0)
525 				return ret;
526 		} else {
527 			dev_err(&client->dev, "no platform data\n");
528 			return -EINVAL;
529 		}
530 	}
531 	pdata = dev_get_platdata(&client->dev);
532 
533 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
534 	if (!chip)
535 		return -ENOMEM;
536 
537 	led = devm_kzalloc(&client->dev,
538 			sizeof(*led) * pdata->num_channels, GFP_KERNEL);
539 	if (!led)
540 		return -ENOMEM;
541 
542 	chip->cl = client;
543 	chip->pdata = pdata;
544 	chip->cfg = &lp5562_cfg;
545 
546 	mutex_init(&chip->lock);
547 
548 	i2c_set_clientdata(client, led);
549 
550 	ret = lp55xx_init_device(chip);
551 	if (ret)
552 		goto err_init;
553 
554 	ret = lp55xx_register_leds(led, chip);
555 	if (ret)
556 		goto err_register_leds;
557 
558 	ret = lp55xx_register_sysfs(chip);
559 	if (ret) {
560 		dev_err(&client->dev, "registering sysfs failed\n");
561 		goto err_register_sysfs;
562 	}
563 
564 	return 0;
565 
566 err_register_sysfs:
567 	lp55xx_unregister_leds(led, chip);
568 err_register_leds:
569 	lp55xx_deinit_device(chip);
570 err_init:
571 	return ret;
572 }
573 
574 static int lp5562_remove(struct i2c_client *client)
575 {
576 	struct lp55xx_led *led = i2c_get_clientdata(client);
577 	struct lp55xx_chip *chip = led->chip;
578 
579 	lp5562_stop_engine(chip);
580 
581 	lp55xx_unregister_sysfs(chip);
582 	lp55xx_unregister_leds(led, chip);
583 	lp55xx_deinit_device(chip);
584 
585 	return 0;
586 }
587 
588 static const struct i2c_device_id lp5562_id[] = {
589 	{ "lp5562", 0 },
590 	{ }
591 };
592 MODULE_DEVICE_TABLE(i2c, lp5562_id);
593 
594 #ifdef CONFIG_OF
595 static const struct of_device_id of_lp5562_leds_match[] = {
596 	{ .compatible = "ti,lp5562", },
597 	{},
598 };
599 
600 MODULE_DEVICE_TABLE(of, of_lp5562_leds_match);
601 #endif
602 
603 static struct i2c_driver lp5562_driver = {
604 	.driver = {
605 		.name	= "lp5562",
606 		.of_match_table = of_match_ptr(of_lp5562_leds_match),
607 	},
608 	.probe		= lp5562_probe,
609 	.remove		= lp5562_remove,
610 	.id_table	= lp5562_id,
611 };
612 
613 module_i2c_driver(lp5562_driver);
614 
615 MODULE_DESCRIPTION("Texas Instruments LP5562 LED Driver");
616 MODULE_AUTHOR("Milo Kim");
617 MODULE_LICENSE("GPL");
618