aboutsummaryrefslogtreecommitdiff
path: root/drivers/leds/leds-lp55xx-common.c
blob: d1657c46ee2f81e44a1b6389d33f2a19972350bc (plain)
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
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
// SPDX-License-Identifier: GPL-2.0-only
/*
 * LP5521/LP5523/LP55231/LP5562 Common Driver
 *
 * Copyright 2012 Texas Instruments
 *
 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
 *
 * Derived from leds-lp5521.c, leds-lp5523.c
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/platform_data/leds-lp55xx.h>
#include <linux/slab.h>
#include <linux/gpio/consumer.h>

#include "leds-lp55xx-common.h"

/* External clock rate */
#define LP55XX_CLK_32K			32768

static struct lp55xx_led *cdev_to_lp55xx_led(struct led_classdev *cdev)
{
	return container_of(cdev, struct lp55xx_led, cdev);
}

static struct lp55xx_led *dev_to_lp55xx_led(struct device *dev)
{
	return cdev_to_lp55xx_led(dev_get_drvdata(dev));
}

static struct lp55xx_led *mcled_cdev_to_led(struct led_classdev_mc *mc_cdev)
{
	return container_of(mc_cdev, struct lp55xx_led, mc_cdev);
}

static void lp55xx_reset_device(struct lp55xx_chip *chip)
{
	struct lp55xx_device_config *cfg = chip->cfg;
	u8 addr = cfg->reset.addr;
	u8 val  = cfg->reset.val;

	/* no error checking here because no ACK from the device after reset */
	lp55xx_write(chip, addr, val);
}

static int lp55xx_detect_device(struct lp55xx_chip *chip)
{
	struct lp55xx_device_config *cfg = chip->cfg;
	u8 addr = cfg->enable.addr;
	u8 val  = cfg->enable.val;
	int ret;

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

	usleep_range(1000, 2000);

	ret = lp55xx_read(chip, addr, &val);
	if (ret)
		return ret;

	if (val != cfg->enable.val)
		return -ENODEV;

	return 0;
}

static int lp55xx_post_init_device(struct lp55xx_chip *chip)
{
	struct lp55xx_device_config *cfg = chip->cfg;

	if (!cfg->post_init_device)
		return 0;

	return cfg->post_init_device(chip);
}

static ssize_t led_current_show(struct device *dev,
			    struct device_attribute *attr,
			    char *buf)
{
	struct lp55xx_led *led = dev_to_lp55xx_led(dev);

	return scnprintf(buf, PAGE_SIZE, "%d\n", led->led_current);
}

static ssize_t led_current_store(struct device *dev,
			     struct device_attribute *attr,
			     const char *buf, size_t len)
{
	struct lp55xx_led *led = dev_to_lp55xx_led(dev);
	struct lp55xx_chip *chip = led->chip;
	unsigned long curr;

	if (kstrtoul(buf, 0, &curr))
		return -EINVAL;

	if (curr > led->max_current)
		return -EINVAL;

	if (!chip->cfg->set_led_current)
		return len;

	mutex_lock(&chip->lock);
	chip->cfg->set_led_current(led, (u8)curr);
	mutex_unlock(&chip->lock);

	return len;
}

static ssize_t max_current_show(struct device *dev,
			    struct device_attribute *attr,
			    char *buf)
{
	struct lp55xx_led *led = dev_to_lp55xx_led(dev);

	return scnprintf(buf, PAGE_SIZE, "%d\n", led->max_current);
}

static DEVICE_ATTR_RW(led_current);
static DEVICE_ATTR_RO(max_current);

static struct attribute *lp55xx_led_attrs[] = {
	&dev_attr_led_current.attr,
	&dev_attr_max_current.attr,
	NULL,
};
ATTRIBUTE_GROUPS(lp55xx_led);

static int lp55xx_set_mc_brightness(struct led_classdev *cdev,
				    enum led_brightness brightness)
{
	struct led_classdev_mc *mc_dev = lcdev_to_mccdev(cdev);
	struct lp55xx_led *led = mcled_cdev_to_led(mc_dev);
	struct lp55xx_device_config *cfg = led->chip->cfg;

	led_mc_calc_color_components(&led->mc_cdev, brightness);
	return cfg->multicolor_brightness_fn(led);

}

static int lp55xx_set_brightness(struct led_classdev *cdev,
			     enum led_brightness brightness)
{
	struct lp55xx_led *led = cdev_to_lp55xx_led(cdev);
	struct lp55xx_device_config *cfg = led->chip->cfg;

	led->brightness = (u8)brightness;
	return cfg->brightness_fn(led);
}

static int lp55xx_init_led(struct lp55xx_led *led,
			struct lp55xx_chip *chip, int chan)
{
	struct lp55xx_platform_data *pdata = chip->pdata;
	struct lp55xx_device_config *cfg = chip->cfg;
	struct device *dev = &chip->cl->dev;
	int max_channel = cfg->max_channel;
	struct mc_subled *mc_led_info;
	struct led_classdev *led_cdev;
	char name[32];
	int i, j = 0;
	int ret;

	if (chan >= max_channel) {
		dev_err(dev, "invalid channel: %d / %d\n", chan, max_channel);
		return -EINVAL;
	}

	if (pdata->led_config[chan].led_current == 0)
		return 0;

	if (pdata->led_config[chan].name) {
		led->cdev.name = pdata->led_config[chan].name;
	} else {
		snprintf(name, sizeof(name), "%s:channel%d",
			pdata->label ? : chip->cl->name, chan);
		led->cdev.name = name;
	}

	if (pdata->led_config[chan].num_colors > 1) {
		mc_led_info = devm_kcalloc(dev,
					   pdata->led_config[chan].num_colors,
					   sizeof(*mc_led_info), GFP_KERNEL);
		if (!mc_led_info)
			return -ENOMEM;

		led_cdev = &led->mc_cdev.led_cdev;
		led_cdev->name = led->cdev.name;
		led_cdev->brightness_set_blocking = lp55xx_set_mc_brightness;
		led->mc_cdev.num_colors = pdata->led_config[chan].num_colors;
		for (i = 0; i < led->mc_cdev.num_colors; i++) {
			mc_led_info[i].color_index =
				pdata->led_config[chan].color_id[i];
			mc_led_info[i].channel =
					pdata->led_config[chan].output_num[i];
			j++;
		}

		led->mc_cdev.subled_info = mc_led_info;
	} else {
		led->cdev.brightness_set_blocking = lp55xx_set_brightness;
	}

	led->cdev.groups = lp55xx_led_groups;
	led->cdev.default_trigger = pdata->led_config[chan].default_trigger;
	led->led_current = pdata->led_config[chan].led_current;
	led->max_current = pdata->led_config[chan].max_current;
	led->chan_nr = pdata->led_config[chan].chan_nr;

	if (led->chan_nr >= max_channel) {
		dev_err(dev, "Use channel numbers between 0 and %d\n",
			max_channel - 1);
		return -EINVAL;
	}

	if (pdata->led_config[chan].num_colors > 1)
		ret = devm_led_classdev_multicolor_register(dev, &led->mc_cdev);
	else
		ret = devm_led_classdev_register(dev, &led->cdev);

	if (ret) {
		dev_err(dev, "led register err: %d\n", ret);
		return ret;
	}

	return 0;
}

static void lp55xx_firmware_loaded(const struct firmware *fw, void *context)
{
	struct lp55xx_chip *chip = context;
	struct device *dev = &chip->cl->dev;
	enum lp55xx_engine_index idx = chip->engine_idx;

	if (!fw) {
		dev_err(dev, "firmware request failed\n");
		return;
	}

	/* handling firmware data is chip dependent */
	mutex_lock(&chip->lock);

	chip->engines[idx - 1].mode = LP55XX_ENGINE_LOAD;
	chip->fw = fw;
	if (chip->cfg->firmware_cb)
		chip->cfg->firmware_cb(chip);

	mutex_unlock(&chip->lock);

	/* firmware should be released for other channel use */
	release_firmware(chip->fw);
	chip->fw = NULL;
}

static int lp55xx_request_firmware(struct lp55xx_chip *chip)
{
	const char *name = chip->cl->name;
	struct device *dev = &chip->cl->dev;

	return request_firmware_nowait(THIS_MODULE, false, name, dev,
				GFP_KERNEL, chip, lp55xx_firmware_loaded);
}

static ssize_t select_engine_show(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;

	return sprintf(buf, "%d\n", chip->engine_idx);
}

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

	if (kstrtoul(buf, 0, &val))
		return -EINVAL;

	/* select the engine to be run */

	switch (val) {
	case LP55XX_ENGINE_1:
	case LP55XX_ENGINE_2:
	case LP55XX_ENGINE_3:
		mutex_lock(&chip->lock);
		chip->engine_idx = val;
		ret = lp55xx_request_firmware(chip);
		mutex_unlock(&chip->lock);
		break;
	default:
		dev_err(dev, "%lu: invalid engine index. (1, 2, 3)\n", val);
		return -EINVAL;
	}

	if (ret) {
		dev_err(dev, "request firmware err: %d\n", ret);
		return ret;
	}

	return len;
}

static inline void lp55xx_run_engine(struct lp55xx_chip *chip, bool start)
{
	if (chip->cfg->run_engine)
		chip->cfg->run_engine(chip, start);
}

static ssize_t run_engine_store(struct device *dev,
			     struct device_attribute *attr,
			     const char *buf, size_t len)
{
	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
	struct lp55xx_chip *chip = led->chip;
	unsigned long val;

	if (kstrtoul(buf, 0, &val))
		return -EINVAL;

	/* run or stop the selected engine */

	if (val <= 0) {
		lp55xx_run_engine(chip, false);
		return len;
	}

	mutex_lock(&chip->lock);
	lp55xx_run_engine(chip, true);
	mutex_unlock(&chip->lock);

	return len;
}

static DEVICE_ATTR_RW(select_engine);
static DEVICE_ATTR_WO(run_engine);

static struct attribute *lp55xx_engine_attributes[] = {
	&dev_attr_select_engine.attr,
	&dev_attr_run_engine.attr,
	NULL,
};

static const struct attribute_group lp55xx_engine_attr_group = {
	.attrs = lp55xx_engine_attributes,
};

int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val)
{
	return i2c_smbus_write_byte_data(chip->cl, reg, val);
}
EXPORT_SYMBOL_GPL(lp55xx_write);

int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val)
{
	s32 ret;

	ret = i2c_smbus_read_byte_data(chip->cl, reg);
	if (ret < 0)
		return ret;

	*val = ret;
	return 0;
}
EXPORT_SYMBOL_GPL(lp55xx_read);

int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val)
{
	int ret;
	u8 tmp;

	ret = lp55xx_read(chip, reg, &tmp);
	if (ret)
		return ret;

	tmp &= ~mask;
	tmp |= val & mask;

	return lp55xx_write(chip, reg, tmp);
}
EXPORT_SYMBOL_GPL(lp55xx_update_bits);

bool lp55xx_is_extclk_used(struct lp55xx_chip *chip)
{
	struct clk *clk;
	int err;

	clk = devm_clk_get(&chip->cl->dev, "32k_clk");
	if (IS_ERR(clk))
		goto use_internal_clk;

	err = clk_prepare_enable(clk);
	if (err)
		goto use_internal_clk;

	if (clk_get_rate(clk) != LP55XX_CLK_32K) {
		clk_disable_unprepare(clk);
		goto use_internal_clk;
	}

	dev_info(&chip->cl->dev, "%dHz external clock used\n",	LP55XX_CLK_32K);

	chip->clk = clk;
	return true;

use_internal_clk:
	dev_info(&chip->cl->dev, "internal clock used\n");
	return false;
}
EXPORT_SYMBOL_GPL(lp55xx_is_extclk_used);

int lp55xx_init_device(struct lp55xx_chip *chip)
{
	struct lp55xx_platform_data *pdata;
	struct lp55xx_device_config *cfg;
	struct device *dev = &chip->cl->dev;
	int ret = 0;

	WARN_ON(!chip);

	pdata = chip->pdata;
	cfg = chip->cfg;

	if (!pdata || !cfg)
		return -EINVAL;

	if (pdata->enable_gpiod) {
		gpiod_set_consumer_name(pdata->enable_gpiod, "LP55xx enable");
		gpiod_set_value(pdata->enable_gpiod, 0);
		usleep_range(1000, 2000); /* Keep enable down at least 1ms */
		gpiod_set_value(pdata->enable_gpiod, 1);
		usleep_range(1000, 2000); /* 500us abs min. */
	}

	lp55xx_reset_device(chip);

	/*
	 * Exact value is not available. 10 - 20ms
	 * appears to be enough for reset.
	 */
	usleep_range(10000, 20000);

	ret = lp55xx_detect_device(chip);
	if (ret) {
		dev_err(dev, "device detection err: %d\n", ret);
		goto err;
	}

	/* chip specific initialization */
	ret = lp55xx_post_init_device(chip);
	if (ret) {
		dev_err(dev, "post init device err: %d\n", ret);
		goto err_post_init;
	}

	return 0;

err_post_init:
	lp55xx_deinit_device(chip);
err:
	return ret;
}
EXPORT_SYMBOL_GPL(lp55xx_init_device);

void lp55xx_deinit_device(struct lp55xx_chip *chip)
{
	struct lp55xx_platform_data *pdata = chip->pdata;

	if (chip->clk)
		clk_disable_unprepare(chip->clk);

	if (pdata->enable_gpiod)
		gpiod_set_value(pdata->enable_gpiod, 0);
}
EXPORT_SYMBOL_GPL(lp55xx_deinit_device);

int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
{
	struct lp55xx_platform_data *pdata = chip->pdata;
	struct lp55xx_device_config *cfg = chip->cfg;
	int num_channels = pdata->num_channels;
	struct lp55xx_led *each;
	u8 led_current;
	int ret;
	int i;

	if (!cfg->brightness_fn) {
		dev_err(&chip->cl->dev, "empty brightness configuration\n");
		return -EINVAL;
	}

	for (i = 0; i < num_channels; i++) {

		/* do not initialize channels that are not connected */
		if (pdata->led_config[i].led_current == 0)
			continue;

		led_current = pdata->led_config[i].led_current;
		each = led + i;
		ret = lp55xx_init_led(each, chip, i);
		if (ret)
			goto err_init_led;

		chip->num_leds++;
		each->chip = chip;

		/* setting led current at each channel */
		if (cfg->set_led_current)
			cfg->set_led_current(each, led_current);
	}

	return 0;

err_init_led:
	return ret;
}
EXPORT_SYMBOL_GPL(lp55xx_register_leds);

int lp55xx_register_sysfs(struct lp55xx_chip *chip)
{
	struct device *dev = &chip->cl->dev;
	struct lp55xx_device_config *cfg = chip->cfg;
	int ret;

	if (!cfg->run_engine || !cfg->firmware_cb)
		goto dev_specific_attrs;

	ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
	if (ret)
		return ret;

dev_specific_attrs:
	return cfg->dev_attr_group ?
		sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0;
}
EXPORT_SYMBOL_GPL(lp55xx_register_sysfs);

void lp55xx_unregister_sysfs(struct lp55xx_chip *chip)
{
	struct device *dev = &chip->cl->dev;
	struct lp55xx_device_config *cfg = chip->cfg;

	if (cfg->dev_attr_group)
		sysfs_remove_group(&dev->kobj, cfg->dev_attr_group);

	sysfs_remove_group(&dev->kobj, &lp55xx_engine_attr_group);
}
EXPORT_SYMBOL_GPL(lp55xx_unregister_sysfs);

static int lp55xx_parse_common_child(struct device_node *np,
				     struct lp55xx_led_config *cfg,
				     int led_number, int *chan_nr)
{
	int ret;

	of_property_read_string(np, "chan-name",
				&cfg[led_number].name);
	of_property_read_u8(np, "led-cur",
			    &cfg[led_number].led_current);
	of_property_read_u8(np, "max-cur",
			    &cfg[led_number].max_current);

	ret = of_property_read_u32(np, "reg", chan_nr);
	if (ret)
		return ret;

	if (*chan_nr < 0 || *chan_nr > cfg->max_channel)
		return -EINVAL;

	return 0;
}

static int lp55xx_parse_multi_led_child(struct device_node *child,
					 struct lp55xx_led_config *cfg,
					 int child_number, int color_number)
{
	int chan_nr, color_id, ret;

	ret = lp55xx_parse_common_child(child, cfg, child_number, &chan_nr);
	if (ret)
		return ret;

	ret = of_property_read_u32(child, "color", &color_id);
	if (ret)
		return ret;

	cfg[child_number].color_id[color_number] = color_id;
	cfg[child_number].output_num[color_number] = chan_nr;

	return 0;
}

static int lp55xx_parse_multi_led(struct device_node *np,
				  struct lp55xx_led_config *cfg,
				  int child_number)
{
	struct device_node *child;
	int num_colors = 0, ret;

	for_each_available_child_of_node(np, child) {
		ret = lp55xx_parse_multi_led_child(child, cfg, child_number,
						   num_colors);
		if (ret) {
			of_node_put(child);
			return ret;
		}
		num_colors++;
	}

	cfg[child_number].num_colors = num_colors;

	return 0;
}

static int lp55xx_parse_logical_led(struct device_node *np,
				   struct lp55xx_led_config *cfg,
				   int child_number)
{
	int led_color, ret;
	int chan_nr = 0;

	cfg[child_number].default_trigger =
		of_get_property(np, "linux,default-trigger", NULL);

	ret = of_property_read_u32(np, "color", &led_color);
	if (ret)
		return ret;

	if (led_color == LED_COLOR_ID_RGB)
		return lp55xx_parse_multi_led(np, cfg, child_number);

	ret =  lp55xx_parse_common_child(np, cfg, child_number, &chan_nr);
	if (ret < 0)
		return ret;

	cfg[child_number].chan_nr = chan_nr;

	return ret;
}

struct lp55xx_platform_data *lp55xx_of_populate_pdata(struct device *dev,
						      struct device_node *np,
						      struct lp55xx_chip *chip)
{
	struct device_node *child;
	struct lp55xx_platform_data *pdata;
	struct lp55xx_led_config *cfg;
	int num_channels;
	int i = 0;
	int ret;

	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return ERR_PTR(-ENOMEM);

	num_channels = of_get_available_child_count(np);
	if (num_channels == 0) {
		dev_err(dev, "no LED channels\n");
		return ERR_PTR(-EINVAL);
	}

	cfg = devm_kcalloc(dev, num_channels, sizeof(*cfg), GFP_KERNEL);
	if (!cfg)
		return ERR_PTR(-ENOMEM);

	pdata->led_config = &cfg[0];
	pdata->num_channels = num_channels;
	cfg->max_channel = chip->cfg->max_channel;

	for_each_available_child_of_node(np, child) {
		ret = lp55xx_parse_logical_led(child, cfg, i);
		if (ret) {
			of_node_put(child);
			return ERR_PTR(-EINVAL);
		}
		i++;
	}

	of_property_read_string(np, "label", &pdata->label);
	of_property_read_u8(np, "clock-mode", &pdata->clock_mode);

	pdata->enable_gpiod = devm_gpiod_get_optional(dev, "enable",
						      GPIOD_OUT_LOW);
	if (IS_ERR(pdata->enable_gpiod))
		return ERR_CAST(pdata->enable_gpiod);

	/* LP8501 specific */
	of_property_read_u8(np, "pwr-sel", (u8 *)&pdata->pwr_sel);

	return pdata;
}
EXPORT_SYMBOL_GPL(lp55xx_of_populate_pdata);

MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
MODULE_DESCRIPTION("LP55xx Common Driver");
MODULE_LICENSE("GPL");