xref: /openbmc/linux/drivers/leds/leds-lp5562.c (revision 8b46168c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * LP5562 LED driver
4  *
5  * Copyright (C) 2013 Texas Instruments
6  *
7  * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
8  */
9 
10 #include <linux/delay.h>
11 #include <linux/firmware.h>
12 #include <linux/i2c.h>
13 #include <linux/leds.h>
14 #include <linux/module.h>
15 #include <linux/mutex.h>
16 #include <linux/of.h>
17 #include <linux/platform_data/leds-lp55xx.h>
18 #include <linux/slab.h>
19 
20 #include "leds-lp55xx-common.h"
21 
22 #define LP5562_PROGRAM_LENGTH		32
23 #define LP5562_MAX_LEDS			4
24 
25 /* ENABLE Register 00h */
26 #define LP5562_REG_ENABLE		0x00
27 #define LP5562_EXEC_ENG1_M		0x30
28 #define LP5562_EXEC_ENG2_M		0x0C
29 #define LP5562_EXEC_ENG3_M		0x03
30 #define LP5562_EXEC_M			0x3F
31 #define LP5562_MASTER_ENABLE		0x40	/* Chip master enable */
32 #define LP5562_LOGARITHMIC_PWM		0x80	/* Logarithmic PWM adjustment */
33 #define LP5562_EXEC_RUN			0x2A
34 #define LP5562_ENABLE_DEFAULT	\
35 	(LP5562_MASTER_ENABLE | LP5562_LOGARITHMIC_PWM)
36 #define LP5562_ENABLE_RUN_PROGRAM	\
37 	(LP5562_ENABLE_DEFAULT | LP5562_EXEC_RUN)
38 
39 /* OPMODE Register 01h */
40 #define LP5562_REG_OP_MODE		0x01
41 #define LP5562_MODE_ENG1_M		0x30
42 #define LP5562_MODE_ENG2_M		0x0C
43 #define LP5562_MODE_ENG3_M		0x03
44 #define LP5562_LOAD_ENG1		0x10
45 #define LP5562_LOAD_ENG2		0x04
46 #define LP5562_LOAD_ENG3		0x01
47 #define LP5562_RUN_ENG1			0x20
48 #define LP5562_RUN_ENG2			0x08
49 #define LP5562_RUN_ENG3			0x02
50 #define LP5562_ENG1_IS_LOADING(mode)	\
51 	((mode & LP5562_MODE_ENG1_M) == LP5562_LOAD_ENG1)
52 #define LP5562_ENG2_IS_LOADING(mode)	\
53 	((mode & LP5562_MODE_ENG2_M) == LP5562_LOAD_ENG2)
54 #define LP5562_ENG3_IS_LOADING(mode)	\
55 	((mode & LP5562_MODE_ENG3_M) == LP5562_LOAD_ENG3)
56 
57 /* BRIGHTNESS Registers */
58 #define LP5562_REG_R_PWM		0x04
59 #define LP5562_REG_G_PWM		0x03
60 #define LP5562_REG_B_PWM		0x02
61 #define LP5562_REG_W_PWM		0x0E
62 
63 /* CURRENT Registers */
64 #define LP5562_REG_R_CURRENT		0x07
65 #define LP5562_REG_G_CURRENT		0x06
66 #define LP5562_REG_B_CURRENT		0x05
67 #define LP5562_REG_W_CURRENT		0x0F
68 
69 /* CONFIG Register 08h */
70 #define LP5562_REG_CONFIG		0x08
71 #define LP5562_PWM_HF			0x40
72 #define LP5562_PWRSAVE_EN		0x20
73 #define LP5562_CLK_INT			0x01	/* Internal clock */
74 #define LP5562_DEFAULT_CFG		(LP5562_PWM_HF | LP5562_PWRSAVE_EN)
75 
76 /* RESET Register 0Dh */
77 #define LP5562_REG_RESET		0x0D
78 #define LP5562_RESET			0xFF
79 
80 /* PROGRAM ENGINE Registers */
81 #define LP5562_REG_PROG_MEM_ENG1	0x10
82 #define LP5562_REG_PROG_MEM_ENG2	0x30
83 #define LP5562_REG_PROG_MEM_ENG3	0x50
84 
85 /* LEDMAP Register 70h */
86 #define LP5562_REG_ENG_SEL		0x70
87 #define LP5562_ENG_SEL_PWM		0
88 #define LP5562_ENG_FOR_RGB_M		0x3F
89 #define LP5562_ENG_SEL_RGB		0x1B	/* R:ENG1, G:ENG2, B:ENG3 */
90 #define LP5562_ENG_FOR_W_M		0xC0
91 #define LP5562_ENG1_FOR_W		0x40	/* W:ENG1 */
92 #define LP5562_ENG2_FOR_W		0x80	/* W:ENG2 */
93 #define LP5562_ENG3_FOR_W		0xC0	/* W:ENG3 */
94 
95 /* Program Commands */
96 #define LP5562_CMD_DISABLE		0x00
97 #define LP5562_CMD_LOAD			0x15
98 #define LP5562_CMD_RUN			0x2A
99 #define LP5562_CMD_DIRECT		0x3F
100 #define LP5562_PATTERN_OFF		0
101 
102 static inline void lp5562_wait_opmode_done(void)
103 {
104 	/* operation mode change needs to be longer than 153 us */
105 	usleep_range(200, 300);
106 }
107 
108 static inline void lp5562_wait_enable_done(void)
109 {
110 	/* it takes more 488 us to update ENABLE register */
111 	usleep_range(500, 600);
112 }
113 
114 static void lp5562_set_led_current(struct lp55xx_led *led, u8 led_current)
115 {
116 	static const u8 addr[] = {
117 		LP5562_REG_R_CURRENT,
118 		LP5562_REG_G_CURRENT,
119 		LP5562_REG_B_CURRENT,
120 		LP5562_REG_W_CURRENT,
121 	};
122 
123 	led->led_current = led_current;
124 	lp55xx_write(led->chip, addr[led->chan_nr], led_current);
125 }
126 
127 static void lp5562_load_engine(struct lp55xx_chip *chip)
128 {
129 	enum lp55xx_engine_index idx = chip->engine_idx;
130 	static const u8 mask[] = {
131 		[LP55XX_ENGINE_1] = LP5562_MODE_ENG1_M,
132 		[LP55XX_ENGINE_2] = LP5562_MODE_ENG2_M,
133 		[LP55XX_ENGINE_3] = LP5562_MODE_ENG3_M,
134 	};
135 
136 	static const u8 val[] = {
137 		[LP55XX_ENGINE_1] = LP5562_LOAD_ENG1,
138 		[LP55XX_ENGINE_2] = LP5562_LOAD_ENG2,
139 		[LP55XX_ENGINE_3] = LP5562_LOAD_ENG3,
140 	};
141 
142 	lp55xx_update_bits(chip, LP5562_REG_OP_MODE, mask[idx], val[idx]);
143 
144 	lp5562_wait_opmode_done();
145 }
146 
147 static void lp5562_stop_engine(struct lp55xx_chip *chip)
148 {
149 	lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DISABLE);
150 	lp5562_wait_opmode_done();
151 }
152 
153 static void lp5562_run_engine(struct lp55xx_chip *chip, bool start)
154 {
155 	int ret;
156 	u8 mode;
157 	u8 exec;
158 
159 	/* stop engine */
160 	if (!start) {
161 		lp55xx_write(chip, LP5562_REG_ENABLE, LP5562_ENABLE_DEFAULT);
162 		lp5562_wait_enable_done();
163 		lp5562_stop_engine(chip);
164 		lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
165 		lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
166 		lp5562_wait_opmode_done();
167 		return;
168 	}
169 
170 	/*
171 	 * To run the engine,
172 	 * operation mode and enable register should updated at the same time
173 	 */
174 
175 	ret = lp55xx_read(chip, LP5562_REG_OP_MODE, &mode);
176 	if (ret)
177 		return;
178 
179 	ret = lp55xx_read(chip, LP5562_REG_ENABLE, &exec);
180 	if (ret)
181 		return;
182 
183 	/* change operation mode to RUN only when each engine is loading */
184 	if (LP5562_ENG1_IS_LOADING(mode)) {
185 		mode = (mode & ~LP5562_MODE_ENG1_M) | LP5562_RUN_ENG1;
186 		exec = (exec & ~LP5562_EXEC_ENG1_M) | LP5562_RUN_ENG1;
187 	}
188 
189 	if (LP5562_ENG2_IS_LOADING(mode)) {
190 		mode = (mode & ~LP5562_MODE_ENG2_M) | LP5562_RUN_ENG2;
191 		exec = (exec & ~LP5562_EXEC_ENG2_M) | LP5562_RUN_ENG2;
192 	}
193 
194 	if (LP5562_ENG3_IS_LOADING(mode)) {
195 		mode = (mode & ~LP5562_MODE_ENG3_M) | LP5562_RUN_ENG3;
196 		exec = (exec & ~LP5562_EXEC_ENG3_M) | LP5562_RUN_ENG3;
197 	}
198 
199 	lp55xx_write(chip, LP5562_REG_OP_MODE, mode);
200 	lp5562_wait_opmode_done();
201 
202 	lp55xx_update_bits(chip, LP5562_REG_ENABLE, LP5562_EXEC_M, exec);
203 	lp5562_wait_enable_done();
204 }
205 
206 static int lp5562_update_firmware(struct lp55xx_chip *chip,
207 					const u8 *data, size_t size)
208 {
209 	enum lp55xx_engine_index idx = chip->engine_idx;
210 	u8 pattern[LP5562_PROGRAM_LENGTH] = {0};
211 	static const u8 addr[] = {
212 		[LP55XX_ENGINE_1] = LP5562_REG_PROG_MEM_ENG1,
213 		[LP55XX_ENGINE_2] = LP5562_REG_PROG_MEM_ENG2,
214 		[LP55XX_ENGINE_3] = LP5562_REG_PROG_MEM_ENG3,
215 	};
216 	unsigned cmd;
217 	char c[3];
218 	int program_size;
219 	int nrchars;
220 	int offset = 0;
221 	int ret;
222 	int i;
223 
224 	/* clear program memory before updating */
225 	for (i = 0; i < LP5562_PROGRAM_LENGTH; i++)
226 		lp55xx_write(chip, addr[idx] + i, 0);
227 
228 	i = 0;
229 	while ((offset < size - 1) && (i < LP5562_PROGRAM_LENGTH)) {
230 		/* separate sscanfs because length is working only for %s */
231 		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
232 		if (ret != 1)
233 			goto err;
234 
235 		ret = sscanf(c, "%2x", &cmd);
236 		if (ret != 1)
237 			goto err;
238 
239 		pattern[i] = (u8)cmd;
240 		offset += nrchars;
241 		i++;
242 	}
243 
244 	/* Each instruction is 16bit long. Check that length is even */
245 	if (i % 2)
246 		goto err;
247 
248 	program_size = i;
249 	for (i = 0; i < program_size; i++)
250 		lp55xx_write(chip, addr[idx] + i, pattern[i]);
251 
252 	return 0;
253 
254 err:
255 	dev_err(&chip->cl->dev, "wrong pattern format\n");
256 	return -EINVAL;
257 }
258 
259 static void lp5562_firmware_loaded(struct lp55xx_chip *chip)
260 {
261 	const struct firmware *fw = chip->fw;
262 
263 	/*
264 	 * the firmware is encoded in ascii hex character, with 2 chars
265 	 * per byte
266 	 */
267 	if (fw->size > (LP5562_PROGRAM_LENGTH * 2)) {
268 		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
269 			fw->size);
270 		return;
271 	}
272 
273 	/*
274 	 * Program memory 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 int lp5562_led_brightness(struct lp55xx_led *led)
316 {
317 	struct lp55xx_chip *chip = led->chip;
318 	static const u8 addr[] = {
319 		LP5562_REG_R_PWM,
320 		LP5562_REG_G_PWM,
321 		LP5562_REG_B_PWM,
322 		LP5562_REG_W_PWM,
323 	};
324 	int ret;
325 
326 	mutex_lock(&chip->lock);
327 	ret = lp55xx_write(chip, addr[led->chan_nr], led->brightness);
328 	mutex_unlock(&chip->lock);
329 
330 	return ret;
331 }
332 
333 static void lp5562_write_program_memory(struct lp55xx_chip *chip,
334 					u8 base, const u8 *rgb, int size)
335 {
336 	int i;
337 
338 	if (!rgb || size <= 0)
339 		return;
340 
341 	for (i = 0; i < size; i++)
342 		lp55xx_write(chip, base + i, *(rgb + i));
343 
344 	lp55xx_write(chip, base + i, 0);
345 	lp55xx_write(chip, base + i + 1, 0);
346 }
347 
348 /* check the size of program count */
349 static inline bool _is_pc_overflow(struct lp55xx_predef_pattern *ptn)
350 {
351 	return ptn->size_r >= LP5562_PROGRAM_LENGTH ||
352 	       ptn->size_g >= LP5562_PROGRAM_LENGTH ||
353 	       ptn->size_b >= LP5562_PROGRAM_LENGTH;
354 }
355 
356 static int lp5562_run_predef_led_pattern(struct lp55xx_chip *chip, int mode)
357 {
358 	struct lp55xx_predef_pattern *ptn;
359 	int i;
360 
361 	if (mode == LP5562_PATTERN_OFF) {
362 		lp5562_run_engine(chip, false);
363 		return 0;
364 	}
365 
366 	ptn = chip->pdata->patterns + (mode - 1);
367 	if (!ptn || _is_pc_overflow(ptn)) {
368 		dev_err(&chip->cl->dev, "invalid pattern data\n");
369 		return -EINVAL;
370 	}
371 
372 	lp5562_stop_engine(chip);
373 
374 	/* Set LED map as RGB */
375 	lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_RGB);
376 
377 	/* Load engines */
378 	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
379 		chip->engine_idx = i;
380 		lp5562_load_engine(chip);
381 	}
382 
383 	/* Clear program registers */
384 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1, 0);
385 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1 + 1, 0);
386 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2, 0);
387 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2 + 1, 0);
388 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3, 0);
389 	lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3 + 1, 0);
390 
391 	/* Program engines */
392 	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG1,
393 				ptn->r, ptn->size_r);
394 	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG2,
395 				ptn->g, ptn->size_g);
396 	lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG3,
397 				ptn->b, ptn->size_b);
398 
399 	/* Run engines */
400 	lp5562_run_engine(chip, true);
401 
402 	return 0;
403 }
404 
405 static ssize_t lp5562_store_pattern(struct device *dev,
406 				struct device_attribute *attr,
407 				const char *buf, size_t len)
408 {
409 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
410 	struct lp55xx_chip *chip = led->chip;
411 	struct lp55xx_predef_pattern *ptn = chip->pdata->patterns;
412 	int num_patterns = chip->pdata->num_patterns;
413 	unsigned long mode;
414 	int ret;
415 
416 	ret = kstrtoul(buf, 0, &mode);
417 	if (ret)
418 		return ret;
419 
420 	if (mode > num_patterns || !ptn)
421 		return -EINVAL;
422 
423 	mutex_lock(&chip->lock);
424 	ret = lp5562_run_predef_led_pattern(chip, mode);
425 	mutex_unlock(&chip->lock);
426 
427 	if (ret)
428 		return ret;
429 
430 	return len;
431 }
432 
433 static ssize_t lp5562_store_engine_mux(struct device *dev,
434 				     struct device_attribute *attr,
435 				     const char *buf, size_t len)
436 {
437 	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
438 	struct lp55xx_chip *chip = led->chip;
439 	u8 mask;
440 	u8 val;
441 
442 	/* LED map
443 	 * R ... Engine 1 (fixed)
444 	 * G ... Engine 2 (fixed)
445 	 * B ... Engine 3 (fixed)
446 	 * W ... Engine 1 or 2 or 3
447 	 */
448 
449 	if (sysfs_streq(buf, "RGB")) {
450 		mask = LP5562_ENG_FOR_RGB_M;
451 		val = LP5562_ENG_SEL_RGB;
452 	} else if (sysfs_streq(buf, "W")) {
453 		enum lp55xx_engine_index idx = chip->engine_idx;
454 
455 		mask = LP5562_ENG_FOR_W_M;
456 		switch (idx) {
457 		case LP55XX_ENGINE_1:
458 			val = LP5562_ENG1_FOR_W;
459 			break;
460 		case LP55XX_ENGINE_2:
461 			val = LP5562_ENG2_FOR_W;
462 			break;
463 		case LP55XX_ENGINE_3:
464 			val = LP5562_ENG3_FOR_W;
465 			break;
466 		default:
467 			return -EINVAL;
468 		}
469 
470 	} else {
471 		dev_err(dev, "choose RGB or W\n");
472 		return -EINVAL;
473 	}
474 
475 	mutex_lock(&chip->lock);
476 	lp55xx_update_bits(chip, LP5562_REG_ENG_SEL, mask, val);
477 	mutex_unlock(&chip->lock);
478 
479 	return len;
480 }
481 
482 static LP55XX_DEV_ATTR_WO(led_pattern, lp5562_store_pattern);
483 static LP55XX_DEV_ATTR_WO(engine_mux, lp5562_store_engine_mux);
484 
485 static struct attribute *lp5562_attributes[] = {
486 	&dev_attr_led_pattern.attr,
487 	&dev_attr_engine_mux.attr,
488 	NULL,
489 };
490 
491 static const struct attribute_group lp5562_group = {
492 	.attrs = lp5562_attributes,
493 };
494 
495 /* Chip specific configurations */
496 static struct lp55xx_device_config lp5562_cfg = {
497 	.max_channel  = LP5562_MAX_LEDS,
498 	.reset = {
499 		.addr = LP5562_REG_RESET,
500 		.val  = LP5562_RESET,
501 	},
502 	.enable = {
503 		.addr = LP5562_REG_ENABLE,
504 		.val  = LP5562_ENABLE_DEFAULT,
505 	},
506 	.post_init_device   = lp5562_post_init_device,
507 	.set_led_current    = lp5562_set_led_current,
508 	.brightness_fn      = lp5562_led_brightness,
509 	.run_engine         = lp5562_run_engine,
510 	.firmware_cb        = lp5562_firmware_loaded,
511 	.dev_attr_group     = &lp5562_group,
512 };
513 
514 static int lp5562_probe(struct i2c_client *client)
515 {
516 	int ret;
517 	struct lp55xx_chip *chip;
518 	struct lp55xx_led *led;
519 	struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
520 	struct device_node *np = dev_of_node(&client->dev);
521 
522 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
523 	if (!chip)
524 		return -ENOMEM;
525 
526 	chip->cfg = &lp5562_cfg;
527 
528 	if (!pdata) {
529 		if (np) {
530 			pdata = lp55xx_of_populate_pdata(&client->dev, np,
531 							 chip);
532 			if (IS_ERR(pdata))
533 				return PTR_ERR(pdata);
534 		} else {
535 			dev_err(&client->dev, "no platform data\n");
536 			return -EINVAL;
537 		}
538 	}
539 
540 
541 	led = devm_kcalloc(&client->dev,
542 			pdata->num_channels, sizeof(*led), GFP_KERNEL);
543 	if (!led)
544 		return -ENOMEM;
545 
546 	chip->cl = client;
547 	chip->pdata = pdata;
548 
549 	mutex_init(&chip->lock);
550 
551 	i2c_set_clientdata(client, led);
552 
553 	ret = lp55xx_init_device(chip);
554 	if (ret)
555 		goto err_init;
556 
557 	ret = lp55xx_register_leds(led, chip);
558 	if (ret)
559 		goto err_out;
560 
561 	ret = lp55xx_register_sysfs(chip);
562 	if (ret) {
563 		dev_err(&client->dev, "registering sysfs failed\n");
564 		goto err_out;
565 	}
566 
567 	return 0;
568 
569 err_out:
570 	lp55xx_deinit_device(chip);
571 err_init:
572 	return ret;
573 }
574 
575 static void 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_deinit_device(chip);
584 }
585 
586 static const struct i2c_device_id lp5562_id[] = {
587 	{ "lp5562", 0 },
588 	{ }
589 };
590 MODULE_DEVICE_TABLE(i2c, lp5562_id);
591 
592 #ifdef CONFIG_OF
593 static const struct of_device_id of_lp5562_leds_match[] = {
594 	{ .compatible = "ti,lp5562", },
595 	{},
596 };
597 
598 MODULE_DEVICE_TABLE(of, of_lp5562_leds_match);
599 #endif
600 
601 static struct i2c_driver lp5562_driver = {
602 	.driver = {
603 		.name	= "lp5562",
604 		.of_match_table = of_match_ptr(of_lp5562_leds_match),
605 	},
606 	.probe_new	= lp5562_probe,
607 	.remove		= lp5562_remove,
608 	.id_table	= lp5562_id,
609 };
610 
611 module_i2c_driver(lp5562_driver);
612 
613 MODULE_DESCRIPTION("Texas Instruments LP5562 LED Driver");
614 MODULE_AUTHOR("Milo Kim");
615 MODULE_LICENSE("GPL");
616