aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/leds/leds-lp5521.c
blob: 6f0272249dc8f227546eb15173428af56c61cc46 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
// SPDX-License-Identifier: GPL-2.0-only
/*
 * LP5521 LED chip driver.
 *
 * Copyright (C) 2010 Nokia Corporation
 * Copyright (C) 2012 Texas Instruments
 *
 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
 *          Milo(Woogyom) Kim <milo.kim@ti.com>
 */

#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_data/leds-lp55xx.h>
#include <linux/slab.h>
#include <linux/of.h>

#include "leds-lp55xx-common.h"

#define LP5521_PROGRAM_LENGTH		32
#define LP5521_MAX_LEDS			3
#define LP5521_CMD_DIRECT		0x3F

/* Registers */
#define LP5521_REG_ENABLE		0x00
#define LP5521_REG_OP_MODE		0x01
#define LP5521_REG_R_PWM		0x02
#define LP5521_REG_G_PWM		0x03
#define LP5521_REG_B_PWM		0x04
#define LP5521_REG_R_CURRENT		0x05
#define LP5521_REG_G_CURRENT		0x06
#define LP5521_REG_B_CURRENT		0x07
#define LP5521_REG_CONFIG		0x08
#define LP5521_REG_STATUS		0x0C
#define LP5521_REG_RESET		0x0D
#define LP5521_REG_R_PROG_MEM		0x10
#define LP5521_REG_G_PROG_MEM		0x30
#define LP5521_REG_B_PROG_MEM		0x50

/* Base register to set LED current */
#define LP5521_REG_LED_CURRENT_BASE	LP5521_REG_R_CURRENT
/* Base register to set the brightness */
#define LP5521_REG_LED_PWM_BASE		LP5521_REG_R_PWM

/* Bits in ENABLE register */
#define LP5521_MASTER_ENABLE		0x40	/* Chip master enable */
#define LP5521_LOGARITHMIC_PWM		0x80	/* Logarithmic PWM adjustment */
#define LP5521_EXEC_RUN			0x2A
#define LP5521_ENABLE_DEFAULT	\
	(LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
#define LP5521_ENABLE_RUN_PROGRAM	\
	(LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)

/* CONFIG register */
#define LP5521_PWM_HF			0x40	/* PWM: 0 = 256Hz, 1 = 558Hz */
#define LP5521_PWRSAVE_EN		0x20	/* 1 = Power save mode */
#define LP5521_CP_MODE_OFF		0	/* Charge pump (CP) off */
#define LP5521_CP_MODE_BYPASS		8	/* CP forced to bypass mode */
#define LP5521_CP_MODE_1X5		0x10	/* CP forced to 1.5x mode */
#define LP5521_CP_MODE_AUTO		0x18	/* Automatic mode selection */
#define LP5521_R_TO_BATT		0x04	/* R out: 0 = CP, 1 = Vbat */
#define LP5521_CLK_INT			0x01	/* Internal clock */
#define LP5521_DEFAULT_CFG		\
	(LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO)

/* Status */
#define LP5521_EXT_CLK_USED		0x08

/* default R channel current register value */
#define LP5521_REG_R_CURR_DEFAULT	0xAF

/* Reset register value */
#define LP5521_RESET			0xFF

/* Program Memory Operations */
#define LP5521_MODE_R_M			0x30	/* Operation Mode Register */
#define LP5521_MODE_G_M			0x0C
#define LP5521_MODE_B_M			0x03
#define LP5521_LOAD_R			0x10
#define LP5521_LOAD_G			0x04
#define LP5521_LOAD_B			0x01

#define LP5521_R_IS_LOADING(mode)	\
	((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
#define LP5521_G_IS_LOADING(mode)	\
	((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
#define LP5521_B_IS_LOADING(mode)	\
	((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)

#define LP5521_EXEC_R_M			0x30	/* Enable Register */
#define LP5521_EXEC_G_M			0x0C
#define LP5521_EXEC_B_M			0x03
#define LP5521_EXEC_M			0x3F
#define LP5521_RUN_R			0x20
#define LP5521_RUN_G			0x08
#define LP5521_RUN_B			0x02

static inline void lp5521_wait_opmode_done(void)
{
	/* operation mode change needs to be longer than 153 us */
	usleep_range(200, 300);
}

static inline void lp5521_wait_enable_done(void)
{
	/* it takes more 488 us to update ENABLE register */
	usleep_range(500, 600);
}

static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
{
	led->led_current = led_current;
	lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr,
		led_current);
}

static void lp5521_load_engine(struct lp55xx_chip *chip)
{
	enum lp55xx_engine_index idx = chip->engine_idx;
	static const u8 mask[] = {
		[LP55XX_ENGINE_1] = LP5521_MODE_R_M,
		[LP55XX_ENGINE_2] = LP5521_MODE_G_M,
		[LP55XX_ENGINE_3] = LP5521_MODE_B_M,
	};

	static const u8 val[] = {
		[LP55XX_ENGINE_1] = LP5521_LOAD_R,
		[LP55XX_ENGINE_2] = LP5521_LOAD_G,
		[LP55XX_ENGINE_3] = LP5521_LOAD_B,
	};

	lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]);

	lp5521_wait_opmode_done();
}

static void lp5521_stop_all_engines(struct lp55xx_chip *chip)
{
	lp55xx_write(chip, LP5521_REG_OP_MODE, 0);
	lp5521_wait_opmode_done();
}

static void lp5521_stop_engine(struct lp55xx_chip *chip)
{
	enum lp55xx_engine_index idx = chip->engine_idx;
	static const u8 mask[] = {
		[LP55XX_ENGINE_1] = LP5521_MODE_R_M,
		[LP55XX_ENGINE_2] = LP5521_MODE_G_M,
		[LP55XX_ENGINE_3] = LP5521_MODE_B_M,
	};

	lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0);

	lp5521_wait_opmode_done();
}

static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
{
	int ret;
	u8 mode;
	u8 exec;

	/* stop engine */
	if (!start) {
		lp5521_stop_engine(chip);
		lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
		lp5521_wait_opmode_done();
		return;
	}

	/*
	 * To run the engine,
	 * operation mode and enable register should updated at the same time
	 */

	ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode);
	if (ret)
		return;

	ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec);
	if (ret)
		return;

	/* change operation mode to RUN only when each engine is loading */
	if (LP5521_R_IS_LOADING(mode)) {
		mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R;
		exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R;
	}

	if (LP5521_G_IS_LOADING(mode)) {
		mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G;
		exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G;
	}

	if (LP5521_B_IS_LOADING(mode)) {
		mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B;
		exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B;
	}

	lp55xx_write(chip, LP5521_REG_OP_MODE, mode);
	lp5521_wait_opmode_done();

	lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec);
	lp5521_wait_enable_done();
}

static int lp5521_update_program_memory(struct lp55xx_chip *chip,
					const u8 *data, size_t size)
{
	enum lp55xx_engine_index idx = chip->engine_idx;
	u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
	static const u8 addr[] = {
		[LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM,
		[LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM,
		[LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM,
	};
	unsigned cmd;
	char c[3];
	int nrchars;
	int ret;
	int offset = 0;
	int i = 0;

	while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
		/* separate sscanfs because length is working only for %s */
		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
		if (ret != 1)
			goto err;

		ret = sscanf(c, "%2x", &cmd);
		if (ret != 1)
			goto err;

		pattern[i] = (u8)cmd;
		offset += nrchars;
		i++;
	}

	/* Each instruction is 16bit long. Check that length is even */
	if (i % 2)
		goto err;

	for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
		ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
		if (ret)
			return -EINVAL;
	}

	return size;

err:
	dev_err(&chip->cl->dev, "wrong pattern format\n");
	return -EINVAL;
}

static void lp5521_firmware_loaded(struct lp55xx_chip *chip)
{
	const struct firmware *fw = chip->fw;

	if (fw->size > LP5521_PROGRAM_LENGTH) {
		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
			fw->size);
		return;
	}

	/*
	 * Program memory sequence
	 *  1) set engine mode to "LOAD"
	 *  2) write firmware data into program memory
	 */

	lp5521_load_engine(chip);
	lp5521_update_program_memory(chip, fw->data, fw->size);
}

static int lp5521_post_init_device(struct lp55xx_chip *chip)
{
	int ret;
	u8 val;

	/*
	 * Make sure that the chip is reset by reading back the r channel
	 * current reg. This is dummy read is required on some platforms -
	 * otherwise further access to the R G B channels in the
	 * LP5521_REG_ENABLE register will not have any effect - strange!
	 */
	ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
	if (ret) {
		dev_err(&chip->cl->dev, "error in resetting chip\n");
		return ret;
	}
	if (val != LP5521_REG_R_CURR_DEFAULT) {
		dev_err(&chip->cl->dev,
			"unexpected data in register (expected 0x%x got 0x%x)\n",
			LP5521_REG_R_CURR_DEFAULT, val);
		ret = -EINVAL;
		return ret;
	}
	usleep_range(10000, 20000);

	/* Set all PWMs to direct control mode */
	ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);

	/* Update configuration for the clock setting */
	val = LP5521_DEFAULT_CFG;
	if (!lp55xx_is_extclk_used(chip))
		val |= LP5521_CLK_INT;

	ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
	if (ret)
		return ret;

	/* Initialize all channels PWM to zero -> leds off */
	lp55xx_write(chip, LP5521_REG_R_PWM, 0);
	lp55xx_write(chip, LP5521_REG_G_PWM, 0);
	lp55xx_write(chip, LP5521_REG_B_PWM, 0);

	/* Set engines are set to run state when OP_MODE enables engines */
	ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
	if (ret)
		return ret;

	lp5521_wait_enable_done();

	return 0;
}

static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
{
	struct lp55xx_platform_data *pdata = chip->pdata;
	int ret;
	u8 status;

	ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
	if (ret < 0)
		return ret;

	if (pdata->clock_mode != LP55XX_CLOCK_EXT)
		return 0;

	/* Check that ext clock is really in use if requested */
	if  ((status & LP5521_EXT_CLK_USED) == 0)
		return -EIO;

	return 0;
}

static int lp5521_led_brightness(struct lp55xx_led *led)
{
	struct lp55xx_chip *chip = led->chip;
	int ret;

	mutex_lock(&chip->lock);
	ret = lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr,
		led->brightness);
	mutex_unlock(&chip->lock);

	return ret;
}

static ssize_t show_engine_mode(struct device *dev,
				struct device_attribute *attr,
				char *buf, int nr)
{
	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
	struct lp55xx_chip *chip = led->chip;
	enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;

	switch (mode) {
	case LP55XX_ENGINE_RUN:
		return sprintf(buf, "run\n");
	case LP55XX_ENGINE_LOAD:
		return sprintf(buf, "load\n");
	case LP55XX_ENGINE_DISABLED:
	default:
		return sprintf(buf, "disabled\n");
	}
}
show_mode(1)
show_mode(2)
show_mode(3)

static ssize_t store_engine_mode(struct device *dev,
				 struct device_attribute *attr,
				 const char *buf, size_t len, int nr)
{
	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
	struct lp55xx_chip *chip = led->chip;
	struct lp55xx_engine *engine = &chip->engines[nr - 1];

	mutex_lock(&chip->lock);

	chip->engine_idx = nr;

	if (!strncmp(buf, "run", 3)) {
		lp5521_run_engine(chip, true);
		engine->mode = LP55XX_ENGINE_RUN;
	} else if (!strncmp(buf, "load", 4)) {
		lp5521_stop_engine(chip);
		lp5521_load_engine(chip);
		engine->mode = LP55XX_ENGINE_LOAD;
	} else if (!strncmp(buf, "disabled", 8)) {
		lp5521_stop_engine(chip);
		engine->mode = LP55XX_ENGINE_DISABLED;
	}

	mutex_unlock(&chip->lock);

	return len;
}
store_mode(1)
store_mode(2)
store_mode(3)

static ssize_t store_engine_load(struct device *dev,
			     struct device_attribute *attr,
			     const char *buf, size_t len, int nr)
{
	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
	struct lp55xx_chip *chip = led->chip;
	int ret;

	mutex_lock(&chip->lock);

	chip->engine_idx = nr;
	lp5521_load_engine(chip);
	ret = lp5521_update_program_memory(chip, buf, len);

	mutex_unlock(&chip->lock);

	return ret;
}
store_load(1)
store_load(2)
store_load(3)

static ssize_t lp5521_selftest(struct device *dev,
			       struct device_attribute *attr,
			       char *buf)
{
	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
	struct lp55xx_chip *chip = led->chip;
	int ret;

	mutex_lock(&chip->lock);
	ret = lp5521_run_selftest(chip, buf);
	mutex_unlock(&chip->lock);

	return scnprintf(buf, PAGE_SIZE, "%s\n", ret ? "FAIL" : "OK");
}

/* device attributes */
static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);

static struct attribute *lp5521_attributes[] = {
	&dev_attr_engine1_mode.attr,
	&dev_attr_engine2_mode.attr,
	&dev_attr_engine3_mode.attr,
	&dev_attr_engine1_load.attr,
	&dev_attr_engine2_load.attr,
	&dev_attr_engine3_load.attr,
	&dev_attr_selftest.attr,
	NULL
};

static const struct attribute_group lp5521_group = {
	.attrs = lp5521_attributes,
};

/* Chip specific configurations */
static struct lp55xx_device_config lp5521_cfg = {
	.reset = {
		.addr = LP5521_REG_RESET,
		.val  = LP5521_RESET,
	},
	.enable = {
		.addr = LP5521_REG_ENABLE,
		.val  = LP5521_ENABLE_DEFAULT,
	},
	.max_channel  = LP5521_MAX_LEDS,
	.post_init_device   = lp5521_post_init_device,
	.brightness_fn      = lp5521_led_brightness,
	.set_led_current    = lp5521_set_led_current,
	.firmware_cb        = lp5521_firmware_loaded,
	.run_engine         = lp5521_run_engine,
	.dev_attr_group     = &lp5521_group,
};

static int lp5521_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	int ret;
	struct lp55xx_chip *chip;
	struct lp55xx_led *led;
	struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
	struct device_node *np = client->dev.of_node;

	if (!pdata) {
		if (np) {
			pdata = lp55xx_of_populate_pdata(&client->dev, np);
			if (IS_ERR(pdata))
				return PTR_ERR(pdata);
		} else {
			dev_err(&client->dev, "no platform data\n");
			return -EINVAL;
		}
	}

	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
	if (!chip)
		return -ENOMEM;

	led = devm_kcalloc(&client->dev,
			pdata->num_channels, sizeof(*led), GFP_KERNEL);
	if (!led)
		return -ENOMEM;

	chip->cl = client;
	chip->pdata = pdata;
	chip->cfg = &lp5521_cfg;

	mutex_init(&chip->lock);

	i2c_set_clientdata(client, led);

	ret = lp55xx_init_device(chip);
	if (ret)
		goto err_init;

	dev_info(&client->dev, "%s programmable led chip found\n", id->name);

	ret = lp55xx_register_leds(led, chip);
	if (ret)
		goto err_register_leds;

	ret = lp55xx_register_sysfs(chip);
	if (ret) {
		dev_err(&client->dev, "registering sysfs failed\n");
		goto err_register_sysfs;
	}

	return 0;

err_register_sysfs:
	lp55xx_unregister_leds(led, chip);
err_register_leds:
	lp55xx_deinit_device(chip);
err_init:
	return ret;
}

static int lp5521_remove(struct i2c_client *client)
{
	struct lp55xx_led *led = i2c_get_clientdata(client);
	struct lp55xx_chip *chip = led->chip;

	lp5521_stop_all_engines(chip);
	lp55xx_unregister_sysfs(chip);
	lp55xx_unregister_leds(led, chip);
	lp55xx_deinit_device(chip);

	return 0;
}

static const struct i2c_device_id lp5521_id[] = {
	{ "lp5521", 0 }, /* Three channel chip */
	{ }
};
MODULE_DEVICE_TABLE(i2c, lp5521_id);

#ifdef CONFIG_OF
static const struct of_device_id of_lp5521_leds_match[] = {
	{ .compatible = "national,lp5521", },
	{},
};

MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);
#endif
static struct i2c_driver lp5521_driver = {
	.driver = {
		.name	= "lp5521",
		.of_match_table = of_match_ptr(of_lp5521_leds_match),
	},
	.probe		= lp5521_probe,
	.remove		= lp5521_remove,
	.id_table	= lp5521_id,
};

module_i2c_driver(lp5521_driver);

MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
MODULE_DESCRIPTION("LP5521 LED engine");
MODULE_LICENSE("GPL v2");