xref: /openbmc/linux/drivers/leds/leds-lp5562.c (revision 79f08d9e)
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/init.h>
17 #include <linux/leds.h>
18 #include <linux/module.h>
19 #include <linux/mutex.h>
20 #include <linux/of.h>
21 #include <linux/platform_data/leds-lp55xx.h>
22 #include <linux/slab.h>
23 
24 #include "leds-lp55xx-common.h"
25 
26 #define LP5562_PROGRAM_LENGTH		32
27 #define LP5562_MAX_LEDS			4
28 
29 /* ENABLE Register 00h */
30 #define LP5562_REG_ENABLE		0x00
31 #define LP5562_EXEC_ENG1_M		0x30
32 #define LP5562_EXEC_ENG2_M		0x0C
33 #define LP5562_EXEC_ENG3_M		0x03
34 #define LP5562_EXEC_M			0x3F
35 #define LP5562_MASTER_ENABLE		0x40	/* Chip master enable */
36 #define LP5562_LOGARITHMIC_PWM		0x80	/* Logarithmic PWM adjustment */
37 #define LP5562_EXEC_RUN			0x2A
38 #define LP5562_ENABLE_DEFAULT	\
39 	(LP5562_MASTER_ENABLE | LP5562_LOGARITHMIC_PWM)
40 #define LP5562_ENABLE_RUN_PROGRAM	\
41 	(LP5562_ENABLE_DEFAULT | LP5562_EXEC_RUN)
42 
43 /* OPMODE Register 01h */
44 #define LP5562_REG_OP_MODE		0x01
45 #define LP5562_MODE_ENG1_M		0x30
46 #define LP5562_MODE_ENG2_M		0x0C
47 #define LP5562_MODE_ENG3_M		0x03
48 #define LP5562_LOAD_ENG1		0x10
49 #define LP5562_LOAD_ENG2		0x04
50 #define LP5562_LOAD_ENG3		0x01
51 #define LP5562_RUN_ENG1			0x20
52 #define LP5562_RUN_ENG2			0x08
53 #define LP5562_RUN_ENG3			0x02
54 #define LP5562_ENG1_IS_LOADING(mode)	\
55 	((mode & LP5562_MODE_ENG1_M) == LP5562_LOAD_ENG1)
56 #define LP5562_ENG2_IS_LOADING(mode)	\
57 	((mode & LP5562_MODE_ENG2_M) == LP5562_LOAD_ENG2)
58 #define LP5562_ENG3_IS_LOADING(mode)	\
59 	((mode & LP5562_MODE_ENG3_M) == LP5562_LOAD_ENG3)
60 
61 /* BRIGHTNESS Registers */
62 #define LP5562_REG_R_PWM		0x04
63 #define LP5562_REG_G_PWM		0x03
64 #define LP5562_REG_B_PWM		0x02
65 #define LP5562_REG_W_PWM		0x0E
66 
67 /* CURRENT Registers */
68 #define LP5562_REG_R_CURRENT		0x07
69 #define LP5562_REG_G_CURRENT		0x06
70 #define LP5562_REG_B_CURRENT		0x05
71 #define LP5562_REG_W_CURRENT		0x0F
72 
73 /* CONFIG Register 08h */
74 #define LP5562_REG_CONFIG		0x08
75 #define LP5562_PWM_HF			0x40
76 #define LP5562_PWRSAVE_EN		0x20
77 #define LP5562_CLK_INT			0x01	/* Internal clock */
78 #define LP5562_DEFAULT_CFG		(LP5562_PWM_HF | LP5562_PWRSAVE_EN)
79 
80 /* RESET Register 0Dh */
81 #define LP5562_REG_RESET		0x0D
82 #define LP5562_RESET			0xFF
83 
84 /* PROGRAM ENGINE Registers */
85 #define LP5562_REG_PROG_MEM_ENG1	0x10
86 #define LP5562_REG_PROG_MEM_ENG2	0x30
87 #define LP5562_REG_PROG_MEM_ENG3	0x50
88 
89 /* LEDMAP Register 70h */
90 #define LP5562_REG_ENG_SEL		0x70
91 #define LP5562_ENG_SEL_PWM		0
92 #define LP5562_ENG_FOR_RGB_M		0x3F
93 #define LP5562_ENG_SEL_RGB		0x1B	/* R:ENG1, G:ENG2, B:ENG3 */
94 #define LP5562_ENG_FOR_W_M		0xC0
95 #define LP5562_ENG1_FOR_W		0x40	/* W:ENG1 */
96 #define LP5562_ENG2_FOR_W		0x80	/* W:ENG2 */
97 #define LP5562_ENG3_FOR_W		0xC0	/* W:ENG3 */
98 
99 /* Program Commands */
100 #define LP5562_CMD_DISABLE		0x00
101 #define LP5562_CMD_LOAD			0x15
102 #define LP5562_CMD_RUN			0x2A
103 #define LP5562_CMD_DIRECT		0x3F
104 #define LP5562_PATTERN_OFF		0
105 
106 static inline void lp5562_wait_opmode_done(void)
107 {
108 	/* operation mode change needs to be longer than 153 us */
109 	usleep_range(200, 300);
110 }
111 
112 static inline void lp5562_wait_enable_done(void)
113 {
114 	/* it takes more 488 us to update ENABLE register */
115 	usleep_range(500, 600);
116 }
117 
118 static void lp5562_set_led_current(struct lp55xx_led *led, u8 led_current)
119 {
120 	u8 addr[] = {
121 		LP5562_REG_R_CURRENT,
122 		LP5562_REG_G_CURRENT,
123 		LP5562_REG_B_CURRENT,
124 		LP5562_REG_W_CURRENT,
125 	};
126 
127 	led->led_current = led_current;
128 	lp55xx_write(led->chip, addr[led->chan_nr], led_current);
129 }
130 
131 static void lp5562_load_engine(struct lp55xx_chip *chip)
132 {
133 	enum lp55xx_engine_index idx = chip->engine_idx;
134 	u8 mask[] = {
135 		[LP55XX_ENGINE_1] = LP5562_MODE_ENG1_M,
136 		[LP55XX_ENGINE_2] = LP5562_MODE_ENG2_M,
137 		[LP55XX_ENGINE_3] = LP5562_MODE_ENG3_M,
138 	};
139 
140 	u8 val[] = {
141 		[LP55XX_ENGINE_1] = LP5562_LOAD_ENG1,
142 		[LP55XX_ENGINE_2] = LP5562_LOAD_ENG2,
143 		[LP55XX_ENGINE_3] = LP5562_LOAD_ENG3,
144 	};
145 
146 	lp55xx_update_bits(chip, LP5562_REG_OP_MODE, mask[idx], val[idx]);
147 
148 	lp5562_wait_opmode_done();
149 }
150 
151 static void lp5562_stop_engine(struct lp55xx_chip *chip)
152 {
153 	lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DISABLE);
154 	lp5562_wait_opmode_done();
155 }
156 
157 static void lp5562_run_engine(struct lp55xx_chip *chip, bool start)
158 {
159 	int ret;
160 	u8 mode;
161 	u8 exec;
162 
163 	/* stop engine */
164 	if (!start) {
165 		lp55xx_write(chip, LP5562_REG_ENABLE, LP5562_ENABLE_DEFAULT);
166 		lp5562_wait_enable_done();
167 		lp5562_stop_engine(chip);
168 		lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
169 		lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
170 		lp5562_wait_opmode_done();
171 		return;
172 	}
173 
174 	/*
175 	 * To run the engine,
176 	 * operation mode and enable register should updated at the same time
177 	 */
178 
179 	ret = lp55xx_read(chip, LP5562_REG_OP_MODE, &mode);
180 	if (ret)
181 		return;
182 
183 	ret = lp55xx_read(chip, LP5562_REG_ENABLE, &exec);
184 	if (ret)
185 		return;
186 
187 	/* change operation mode to RUN only when each engine is loading */
188 	if (LP5562_ENG1_IS_LOADING(mode)) {
189 		mode = (mode & ~LP5562_MODE_ENG1_M) | LP5562_RUN_ENG1;
190 		exec = (exec & ~LP5562_EXEC_ENG1_M) | LP5562_RUN_ENG1;
191 	}
192 
193 	if (LP5562_ENG2_IS_LOADING(mode)) {
194 		mode = (mode & ~LP5562_MODE_ENG2_M) | LP5562_RUN_ENG2;
195 		exec = (exec & ~LP5562_EXEC_ENG2_M) | LP5562_RUN_ENG2;
196 	}
197 
198 	if (LP5562_ENG3_IS_LOADING(mode)) {
199 		mode = (mode & ~LP5562_MODE_ENG3_M) | LP5562_RUN_ENG3;
200 		exec = (exec & ~LP5562_EXEC_ENG3_M) | LP5562_RUN_ENG3;
201 	}
202 
203 	lp55xx_write(chip, LP5562_REG_OP_MODE, mode);
204 	lp5562_wait_opmode_done();
205 
206 	lp55xx_update_bits(chip, LP5562_REG_ENABLE, LP5562_EXEC_M, exec);
207 	lp5562_wait_enable_done();
208 }
209 
210 static int lp5562_update_firmware(struct lp55xx_chip *chip,
211 					const u8 *data, size_t size)
212 {
213 	enum lp55xx_engine_index idx = chip->engine_idx;
214 	u8 pattern[LP5562_PROGRAM_LENGTH] = {0};
215 	u8 addr[] = {
216 		[LP55XX_ENGINE_1] = LP5562_REG_PROG_MEM_ENG1,
217 		[LP55XX_ENGINE_2] = LP5562_REG_PROG_MEM_ENG2,
218 		[LP55XX_ENGINE_3] = LP5562_REG_PROG_MEM_ENG3,
219 	};
220 	unsigned cmd;
221 	char c[3];
222 	int program_size;
223 	int nrchars;
224 	int offset = 0;
225 	int ret;
226 	int i;
227 
228 	/* clear program memory before updating */
229 	for (i = 0; i < LP5562_PROGRAM_LENGTH; i++)
230 		lp55xx_write(chip, addr[idx] + i, 0);
231 
232 	i = 0;
233 	while ((offset < size - 1) && (i < LP5562_PROGRAM_LENGTH)) {
234 		/* separate sscanfs because length is working only for %s */
235 		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
236 		if (ret != 1)
237 			goto err;
238 
239 		ret = sscanf(c, "%2x", &cmd);
240 		if (ret != 1)
241 			goto err;
242 
243 		pattern[i] = (u8)cmd;
244 		offset += nrchars;
245 		i++;
246 	}
247 
248 	/* Each instruction is 16bit long. Check that length is even */
249 	if (i % 2)
250 		goto err;
251 
252 	program_size = i;
253 	for (i = 0; i < program_size; i++)
254 		lp55xx_write(chip, addr[idx] + i, pattern[i]);
255 
256 	return 0;
257 
258 err:
259 	dev_err(&chip->cl->dev, "wrong pattern format\n");
260 	return -EINVAL;
261 }
262 
263 static void lp5562_firmware_loaded(struct lp55xx_chip *chip)
264 {
265 	const struct firmware *fw = chip->fw;
266 
267 	if (fw->size > LP5562_PROGRAM_LENGTH) {
268 		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
269 			fw->size);
270 		return;
271 	}
272 
273 	/*
274 	 * Program momery sequence
275 	 *  1) set engine mode to "LOAD"
276 	 *  2) write firmware data into program memory
277 	 */
278 
279 	lp5562_load_engine(chip);
280 	lp5562_update_firmware(chip, fw->data, fw->size);
281 }
282 
283 static int lp5562_post_init_device(struct lp55xx_chip *chip)
284 {
285 	int ret;
286 	u8 cfg = LP5562_DEFAULT_CFG;
287 
288 	/* Set all PWMs to direct control mode */
289 	ret = lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
290 	if (ret)
291 		return ret;
292 
293 	lp5562_wait_opmode_done();
294 
295 	/* Update configuration for the clock setting */
296 	if (!lp55xx_is_extclk_used(chip))
297 		cfg |= LP5562_CLK_INT;
298 
299 	ret = lp55xx_write(chip, LP5562_REG_CONFIG, cfg);
300 	if (ret)
301 		return ret;
302 
303 	/* Initialize all channels PWM to zero -> leds off */
304 	lp55xx_write(chip, LP5562_REG_R_PWM, 0);
305 	lp55xx_write(chip, LP5562_REG_G_PWM, 0);
306 	lp55xx_write(chip, LP5562_REG_B_PWM, 0);
307 	lp55xx_write(chip, LP5562_REG_W_PWM, 0);
308 
309 	/* Set LED map as register PWM by default */
310 	lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
311 
312 	return 0;
313 }
314 
315 static void lp5562_led_brightness_work(struct work_struct *work)
316 {
317 	struct lp55xx_led *led = container_of(work, struct lp55xx_led,
318 					      brightness_work);
319 	struct lp55xx_chip *chip = led->chip;
320 	u8 addr[] = {
321 		LP5562_REG_R_PWM,
322 		LP5562_REG_G_PWM,
323 		LP5562_REG_B_PWM,
324 		LP5562_REG_W_PWM,
325 	};
326 
327 	mutex_lock(&chip->lock);
328 	lp55xx_write(chip, addr[led->chan_nr], led->brightness);
329 	mutex_unlock(&chip->lock);
330 }
331 
332 static void lp5562_write_program_memory(struct lp55xx_chip *chip,
333 					u8 base, const u8 *rgb, int size)
334 {
335 	int i;
336 
337 	if (!rgb || size <= 0)
338 		return;
339 
340 	for (i = 0; i < size; i++)
341 		lp55xx_write(chip, base + i, *(rgb + i));
342 
343 	lp55xx_write(chip, base + i, 0);
344 	lp55xx_write(chip, base + i + 1, 0);
345 }
346 
347 /* check the size of program count */
348 static inline bool _is_pc_overflow(struct lp55xx_predef_pattern *ptn)
349 {
350 	return (ptn->size_r >= LP5562_PROGRAM_LENGTH ||
351 		ptn->size_g >= LP5562_PROGRAM_LENGTH ||
352 		ptn->size_b >= LP5562_PROGRAM_LENGTH);
353 }
354 
355 static int lp5562_run_predef_led_pattern(struct lp55xx_chip *chip, int mode)
356 {
357 	struct lp55xx_predef_pattern *ptn;
358 	int i;
359 
360 	if (mode == LP5562_PATTERN_OFF) {
361 		lp5562_run_engine(chip, false);
362 		return 0;
363 	}
364 
365 	ptn = chip->pdata->patterns + (mode - 1);
366 	if (!ptn || _is_pc_overflow(ptn)) {
367 		dev_err(&chip->cl->dev, "invalid pattern data\n");
368 		return -EINVAL;
369 	}
370 
371 	lp5562_stop_engine(chip);
372 
373 	/* Set LED map as RGB */
374 	lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_RGB);
375 
376 	/* Load engines */
377 	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
378 		chip->engine_idx = i;
379 		lp5562_load_engine(chip);
380 	}
381 
382 	/* Clear program registers */
383 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1, 0);
384 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1 + 1, 0);
385 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2, 0);
386 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2 + 1, 0);
387 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3, 0);
388 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3 + 1, 0);
389 
390 	/* Program engines */
391 	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG1,
392 				ptn->r, ptn->size_r);
393 	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG2,
394 				ptn->g, ptn->size_g);
395 	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG3,
396 				ptn->b, ptn->size_b);
397 
398 	/* Run engines */
399 	lp5562_run_engine(chip, true);
400 
401 	return 0;
402 }
403 
404 static ssize_t lp5562_store_pattern(struct device *dev,
405 				struct device_attribute *attr,
406 				const char *buf, size_t len)
407 {
408 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
409 	struct lp55xx_chip *chip = led->chip;
410 	struct lp55xx_predef_pattern *ptn = chip->pdata->patterns;
411 	int num_patterns = chip->pdata->num_patterns;
412 	unsigned long mode;
413 	int ret;
414 
415 	ret = kstrtoul(buf, 0, &mode);
416 	if (ret)
417 		return ret;
418 
419 	if (mode > num_patterns || !ptn)
420 		return -EINVAL;
421 
422 	mutex_lock(&chip->lock);
423 	ret = lp5562_run_predef_led_pattern(chip, mode);
424 	mutex_unlock(&chip->lock);
425 
426 	if (ret)
427 		return ret;
428 
429 	return len;
430 }
431 
432 static ssize_t lp5562_store_engine_mux(struct device *dev,
433 				     struct device_attribute *attr,
434 				     const char *buf, size_t len)
435 {
436 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
437 	struct lp55xx_chip *chip = led->chip;
438 	u8 mask;
439 	u8 val;
440 
441 	/* LED map
442 	 * R ... Engine 1 (fixed)
443 	 * G ... Engine 2 (fixed)
444 	 * B ... Engine 3 (fixed)
445 	 * W ... Engine 1 or 2 or 3
446 	 */
447 
448 	if (sysfs_streq(buf, "RGB")) {
449 		mask = LP5562_ENG_FOR_RGB_M;
450 		val = LP5562_ENG_SEL_RGB;
451 	} else if (sysfs_streq(buf, "W")) {
452 		enum lp55xx_engine_index idx = chip->engine_idx;
453 
454 		mask = LP5562_ENG_FOR_W_M;
455 		switch (idx) {
456 		case LP55XX_ENGINE_1:
457 			val = LP5562_ENG1_FOR_W;
458 			break;
459 		case LP55XX_ENGINE_2:
460 			val = LP5562_ENG2_FOR_W;
461 			break;
462 		case LP55XX_ENGINE_3:
463 			val = LP5562_ENG3_FOR_W;
464 			break;
465 		default:
466 			return -EINVAL;
467 		}
468 
469 	} else {
470 		dev_err(dev, "choose RGB or W\n");
471 		return -EINVAL;
472 	}
473 
474 	mutex_lock(&chip->lock);
475 	lp55xx_update_bits(chip, LP5562_REG_ENG_SEL, mask, val);
476 	mutex_unlock(&chip->lock);
477 
478 	return len;
479 }
480 
481 static LP55XX_DEV_ATTR_WO(led_pattern, lp5562_store_pattern);
482 static LP55XX_DEV_ATTR_WO(engine_mux, lp5562_store_engine_mux);
483 
484 static struct attribute *lp5562_attributes[] = {
485 	&dev_attr_led_pattern.attr,
486 	&dev_attr_engine_mux.attr,
487 	NULL,
488 };
489 
490 static const struct attribute_group lp5562_group = {
491 	.attrs = lp5562_attributes,
492 };
493 
494 /* Chip specific configurations */
495 static struct lp55xx_device_config lp5562_cfg = {
496 	.max_channel  = LP5562_MAX_LEDS,
497 	.reset = {
498 		.addr = LP5562_REG_RESET,
499 		.val  = LP5562_RESET,
500 	},
501 	.enable = {
502 		.addr = LP5562_REG_ENABLE,
503 		.val  = LP5562_ENABLE_DEFAULT,
504 	},
505 	.post_init_device   = lp5562_post_init_device,
506 	.set_led_current    = lp5562_set_led_current,
507 	.brightness_work_fn = lp5562_led_brightness_work,
508 	.run_engine         = lp5562_run_engine,
509 	.firmware_cb        = lp5562_firmware_loaded,
510 	.dev_attr_group     = &lp5562_group,
511 };
512 
513 static int lp5562_probe(struct i2c_client *client,
514 			const struct i2c_device_id *id)
515 {
516 	int ret;
517 	struct lp55xx_chip *chip;
518 	struct lp55xx_led *led;
519 	struct lp55xx_platform_data *pdata;
520 	struct device_node *np = client->dev.of_node;
521 
522 	if (!dev_get_platdata(&client->dev)) {
523 		if (np) {
524 			ret = lp55xx_of_populate_pdata(&client->dev, np);
525 			if (ret < 0)
526 				return ret;
527 		} else {
528 			dev_err(&client->dev, "no platform data\n");
529 			return -EINVAL;
530 		}
531 	}
532 	pdata = dev_get_platdata(&client->dev);
533 
534 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
535 	if (!chip)
536 		return -ENOMEM;
537 
538 	led = devm_kzalloc(&client->dev,
539 			sizeof(*led) * pdata->num_channels, GFP_KERNEL);
540 	if (!led)
541 		return -ENOMEM;
542 
543 	chip->cl = client;
544 	chip->pdata = pdata;
545 	chip->cfg = &lp5562_cfg;
546 
547 	mutex_init(&chip->lock);
548 
549 	i2c_set_clientdata(client, led);
550 
551 	ret = lp55xx_init_device(chip);
552 	if (ret)
553 		goto err_init;
554 
555 	ret = lp55xx_register_leds(led, chip);
556 	if (ret)
557 		goto err_register_leds;
558 
559 	ret = lp55xx_register_sysfs(chip);
560 	if (ret) {
561 		dev_err(&client->dev, "registering sysfs failed\n");
562 		goto err_register_sysfs;
563 	}
564 
565 	return 0;
566 
567 err_register_sysfs:
568 	lp55xx_unregister_leds(led, chip);
569 err_register_leds:
570 	lp55xx_deinit_device(chip);
571 err_init:
572 	return ret;
573 }
574 
575 static int lp5562_remove(struct i2c_client *client)
576 {
577 	struct lp55xx_led *led = i2c_get_clientdata(client);
578 	struct lp55xx_chip *chip = led->chip;
579 
580 	lp5562_stop_engine(chip);
581 
582 	lp55xx_unregister_sysfs(chip);
583 	lp55xx_unregister_leds(led, chip);
584 	lp55xx_deinit_device(chip);
585 
586 	return 0;
587 }
588 
589 static const struct i2c_device_id lp5562_id[] = {
590 	{ "lp5562", 0 },
591 	{ }
592 };
593 MODULE_DEVICE_TABLE(i2c, lp5562_id);
594 
595 #ifdef CONFIG_OF
596 static const struct of_device_id of_lp5562_leds_match[] = {
597 	{ .compatible = "ti,lp5562", },
598 	{},
599 };
600 
601 MODULE_DEVICE_TABLE(of, of_lp5562_leds_match);
602 #endif
603 
604 static struct i2c_driver lp5562_driver = {
605 	.driver = {
606 		.name	= "lp5562",
607 		.of_match_table = of_match_ptr(of_lp5562_leds_match),
608 	},
609 	.probe		= lp5562_probe,
610 	.remove		= lp5562_remove,
611 	.id_table	= lp5562_id,
612 };
613 
614 module_i2c_driver(lp5562_driver);
615 
616 MODULE_DESCRIPTION("Texas Instruments LP5562 LED Driver");
617 MODULE_AUTHOR("Milo Kim");
618 MODULE_LICENSE("GPL");
619