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
105static 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
111static 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
117static 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
130static 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
150static 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
156static 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
209static 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
257err:
258	dev_err(&chip->cl->dev, "wrong pattern format\n");
259	return -EINVAL;
260}
261
262static 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
282static 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
314static 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
331static 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 */
347static 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
354static 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
403static 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
431static 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
480static LP55XX_DEV_ATTR_WO(led_pattern, lp5562_store_pattern);
481static LP55XX_DEV_ATTR_WO(engine_mux, lp5562_store_engine_mux);
482
483static struct attribute *lp5562_attributes[] = {
484	&dev_attr_led_pattern.attr,
485	&dev_attr_engine_mux.attr,
486	NULL,
487};
488
489static const struct attribute_group lp5562_group = {
490	.attrs = lp5562_attributes,
491};
492
493/* Chip specific configurations */
494static 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
512static 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
566err_register_sysfs:
567	lp55xx_unregister_leds(led, chip);
568err_register_leds:
569	lp55xx_deinit_device(chip);
570err_init:
571	return ret;
572}
573
574static 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
588static const struct i2c_device_id lp5562_id[] = {
589	{ "lp5562", 0 },
590	{ }
591};
592MODULE_DEVICE_TABLE(i2c, lp5562_id);
593
594#ifdef CONFIG_OF
595static const struct of_device_id of_lp5562_leds_match[] = {
596	{ .compatible = "ti,lp5562", },
597	{},
598};
599
600MODULE_DEVICE_TABLE(of, of_lp5562_leds_match);
601#endif
602
603static 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
613module_i2c_driver(lp5562_driver);
614
615MODULE_DESCRIPTION("Texas Instruments LP5562 LED Driver");
616MODULE_AUTHOR("Milo Kim");
617MODULE_LICENSE("GPL");
618