summaryrefslogtreecommitdiff
path: root/drivers/leds/leds-blinkm.c
blob: 11b771fb933b387714cfc05e370ed35f5b2cc2ce (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
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
/*
 *  leds-blinkm.c
 *  (c) Jan-Simon Möller (dl9pf@gmx.de)
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>
#include <linux/printk.h>
#include <linux/pm_runtime.h>
#include <linux/leds.h>
#include <linux/delay.h>

/* Addresses to scan - BlinkM is on 0x09 by default*/
static const unsigned short normal_i2c[] = { 0x09, I2C_CLIENT_END };

static int blinkm_transfer_hw(struct i2c_client *client, int cmd);
static int blinkm_test_run(struct i2c_client *client);

struct blinkm_led {
	struct i2c_client *i2c_client;
	struct led_classdev led_cdev;
	int id;
};

#define cdev_to_blmled(c)          container_of(c, struct blinkm_led, led_cdev)

struct blinkm_data {
	struct i2c_client *i2c_client;
	struct mutex update_lock;
	/* used for led class interface */
	struct blinkm_led blinkm_leds[3];
	/* used for "blinkm" sysfs interface */
	u8 red;			/* color red */
	u8 green;		/* color green */
	u8 blue;		/* color blue */
	/* next values to use for transfer */
	u8 next_red;			/* color red */
	u8 next_green;		/* color green */
	u8 next_blue;		/* color blue */
	/* internal use */
	u8 args[7];		/* set of args for transmission */
	u8 i2c_addr;		/* i2c addr */
	u8 fw_ver;		/* firmware version */
	/* used, but not from userspace */
	u8 hue;			/* HSB  hue */
	u8 saturation;		/* HSB  saturation */
	u8 brightness;		/* HSB  brightness */
	u8 next_hue;			/* HSB  hue */
	u8 next_saturation;		/* HSB  saturation */
	u8 next_brightness;		/* HSB  brightness */
	/* currently unused / todo */
	u8 fade_speed;		/* fade speed     1 - 255 */
	s8 time_adjust;		/* time adjust -128 - 127 */
	u8 fade:1;		/* fade on = 1, off = 0 */
	u8 rand:1;		/* rand fade mode on = 1 */
	u8 script_id;		/* script ID */
	u8 script_repeats;	/* repeats of script */
	u8 script_startline;	/* line to start */
};

/* Colors */
#define RED   0
#define GREEN 1
#define BLUE  2

/* mapping command names to cmd chars - see datasheet */
#define BLM_GO_RGB            0
#define BLM_FADE_RGB          1
#define BLM_FADE_HSB          2
#define BLM_FADE_RAND_RGB     3
#define BLM_FADE_RAND_HSB     4
#define BLM_PLAY_SCRIPT       5
#define BLM_STOP_SCRIPT       6
#define BLM_SET_FADE_SPEED    7
#define BLM_SET_TIME_ADJ      8
#define BLM_GET_CUR_RGB       9
#define BLM_WRITE_SCRIPT_LINE 10
#define BLM_READ_SCRIPT_LINE  11
#define BLM_SET_SCRIPT_LR     12	/* Length & Repeats */
#define BLM_SET_ADDR          13
#define BLM_GET_ADDR          14
#define BLM_GET_FW_VER        15
#define BLM_SET_STARTUP_PARAM 16

/* BlinkM Commands
 *  as extracted out of the datasheet:
 *
 *  cmdchar = command (ascii)
 *  cmdbyte = command in hex
 *  nr_args = number of arguments (to send)
 *  nr_ret  = number of return values (to read)
 *  dir = direction (0 = read, 1 = write, 2 = both)
 *
 */
static const struct {
	char cmdchar;
	u8 cmdbyte;
	u8 nr_args;
	u8 nr_ret;
	u8 dir:2;
} blinkm_cmds[17] = {
  /* cmdchar, cmdbyte, nr_args, nr_ret,  dir */
	{ 'n', 0x6e, 3, 0, 1},
	{ 'c', 0x63, 3, 0, 1},
	{ 'h', 0x68, 3, 0, 1},
	{ 'C', 0x43, 3, 0, 1},
	{ 'H', 0x48, 3, 0, 1},
	{ 'p', 0x70, 3, 0, 1},
	{ 'o', 0x6f, 0, 0, 1},
	{ 'f', 0x66, 1, 0, 1},
	{ 't', 0x74, 1, 0, 1},
	{ 'g', 0x67, 0, 3, 0},
	{ 'W', 0x57, 7, 0, 1},
	{ 'R', 0x52, 2, 5, 2},
	{ 'L', 0x4c, 3, 0, 1},
	{ 'A', 0x41, 4, 0, 1},
	{ 'a', 0x61, 0, 1, 0},
	{ 'Z', 0x5a, 0, 1, 0},
	{ 'B', 0x42, 5, 0, 1},
};

static ssize_t show_color_common(struct device *dev, char *buf, int color)
{
	struct i2c_client *client;
	struct blinkm_data *data;
	int ret;

	client = to_i2c_client(dev);
	data = i2c_get_clientdata(client);

	ret = blinkm_transfer_hw(client, BLM_GET_CUR_RGB);
	if (ret < 0)
		return ret;
	switch (color) {
	case RED:
		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->red);
	case GREEN:
		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->green);
	case BLUE:
		return scnprintf(buf, PAGE_SIZE, "%02X\n", data->blue);
	default:
		return -EINVAL;
	}
	return -EINVAL;
}

static int store_color_common(struct device *dev, const char *buf, int color)
{
	struct i2c_client *client;
	struct blinkm_data *data;
	int ret;
	u8 value;

	client = to_i2c_client(dev);
	data = i2c_get_clientdata(client);

	ret = kstrtou8(buf, 10, &value);
	if (ret < 0) {
		dev_err(dev, "BlinkM: value too large!\n");
		return ret;
	}

	switch (color) {
	case RED:
		data->next_red = value;
		break;
	case GREEN:
		data->next_green = value;
		break;
	case BLUE:
		data->next_blue = value;
		break;
	default:
		return -EINVAL;
	}

	dev_dbg(dev, "next_red = %d, next_green = %d, next_blue = %d\n",
			data->next_red, data->next_green, data->next_blue);

	/* if mode ... */
	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
	if (ret < 0) {
		dev_err(dev, "BlinkM: can't set RGB\n");
		return ret;
	}
	return 0;
}

static ssize_t show_red(struct device *dev, struct device_attribute *attr,
			char *buf)
{
	return show_color_common(dev, buf, RED);
}

static ssize_t store_red(struct device *dev, struct device_attribute *attr,
			 const char *buf, size_t count)
{
	int ret;

	ret = store_color_common(dev, buf, RED);
	if (ret < 0)
		return ret;
	return count;
}

static DEVICE_ATTR(red, S_IRUGO | S_IWUSR, show_red, store_red);

static ssize_t show_green(struct device *dev, struct device_attribute *attr,
			  char *buf)
{
	return show_color_common(dev, buf, GREEN);
}

static ssize_t store_green(struct device *dev, struct device_attribute *attr,
			   const char *buf, size_t count)
{

	int ret;

	ret = store_color_common(dev, buf, GREEN);
	if (ret < 0)
		return ret;
	return count;
}

static DEVICE_ATTR(green, S_IRUGO | S_IWUSR, show_green, store_green);

static ssize_t show_blue(struct device *dev, struct device_attribute *attr,
			 char *buf)
{
	return show_color_common(dev, buf, BLUE);
}

static ssize_t store_blue(struct device *dev, struct device_attribute *attr,
			  const char *buf, size_t count)
{
	int ret;

	ret = store_color_common(dev, buf, BLUE);
	if (ret < 0)
		return ret;
	return count;
}

static DEVICE_ATTR(blue, S_IRUGO | S_IWUSR, show_blue, store_blue);

static ssize_t show_test(struct device *dev, struct device_attribute *attr,
			 char *buf)
{
	return scnprintf(buf, PAGE_SIZE,
			 "#Write into test to start test sequence!#\n");
}

static ssize_t store_test(struct device *dev, struct device_attribute *attr,
			  const char *buf, size_t count)
{

	struct i2c_client *client;
	int ret;
	client = to_i2c_client(dev);

	/*test */
	ret = blinkm_test_run(client);
	if (ret < 0)
		return ret;

	return count;
}

static DEVICE_ATTR(test, S_IRUGO | S_IWUSR, show_test, store_test);

/* TODO: HSB, fade, timeadj, script ... */

static struct attribute *blinkm_attrs[] = {
	&dev_attr_red.attr,
	&dev_attr_green.attr,
	&dev_attr_blue.attr,
	&dev_attr_test.attr,
	NULL,
};

static const struct attribute_group blinkm_group = {
	.name = "blinkm",
	.attrs = blinkm_attrs,
};

static int blinkm_write(struct i2c_client *client, int cmd, u8 *arg)
{
	int result;
	int i;
	int arglen = blinkm_cmds[cmd].nr_args;
	/* write out cmd to blinkm - always / default step */
	result = i2c_smbus_write_byte(client, blinkm_cmds[cmd].cmdbyte);
	if (result < 0)
		return result;
	/* no args to write out */
	if (arglen == 0)
		return 0;

	for (i = 0; i < arglen; i++) {
		/* repeat for arglen */
		result = i2c_smbus_write_byte(client, arg[i]);
		if (result < 0)
			return result;
	}
	return 0;
}

static int blinkm_read(struct i2c_client *client, int cmd, u8 *arg)
{
	int result;
	int i;
	int retlen = blinkm_cmds[cmd].nr_ret;
	for (i = 0; i < retlen; i++) {
		/* repeat for retlen */
		result = i2c_smbus_read_byte(client);
		if (result < 0)
			return result;
		arg[i] = result;
	}

	return 0;
}

static int blinkm_transfer_hw(struct i2c_client *client, int cmd)
{
	/* the protocol is simple but non-standard:
	 * e.g.  cmd 'g' (= 0x67) for "get device address"
	 * - which defaults to 0x09 - would be the sequence:
	 *   a) write 0x67 to the device (byte write)
	 *   b) read the value (0x09) back right after (byte read)
	 *
	 * Watch out for "unfinished" sequences (i.e. not enough reads
	 * or writes after a command. It will make the blinkM misbehave.
	 * Sequence is key here.
	 */

	/* args / return are in private data struct */
	struct blinkm_data *data = i2c_get_clientdata(client);

	/* We start hardware transfers which are not to be
	 * mixed with other commands. Aquire a lock now. */
	if (mutex_lock_interruptible(&data->update_lock) < 0)
		return -EAGAIN;

	/* switch cmd - usually write before reads */
	switch (cmd) {
	case BLM_FADE_RAND_RGB:
	case BLM_GO_RGB:
	case BLM_FADE_RGB:
		data->args[0] = data->next_red;
		data->args[1] = data->next_green;
		data->args[2] = data->next_blue;
		blinkm_write(client, cmd, data->args);
		data->red = data->args[0];
		data->green = data->args[1];
		data->blue = data->args[2];
		break;
	case BLM_FADE_HSB:
	case BLM_FADE_RAND_HSB:
		data->args[0] = data->next_hue;
		data->args[1] = data->next_saturation;
		data->args[2] = data->next_brightness;
		blinkm_write(client, cmd, data->args);
		data->hue = data->next_hue;
		data->saturation = data->next_saturation;
		data->brightness = data->next_brightness;
		break;
	case BLM_PLAY_SCRIPT:
		data->args[0] = data->script_id;
		data->args[1] = data->script_repeats;
		data->args[2] = data->script_startline;
		blinkm_write(client, cmd, data->args);
		break;
	case BLM_STOP_SCRIPT:
		blinkm_write(client, cmd, NULL);
		break;
	case BLM_GET_CUR_RGB:
		data->args[0] = data->red;
		data->args[1] = data->green;
		data->args[2] = data->blue;
		blinkm_write(client, cmd, NULL);
		blinkm_read(client, cmd, data->args);
		data->red = data->args[0];
		data->green = data->args[1];
		data->blue = data->args[2];
		break;
	case BLM_GET_ADDR:
		data->args[0] = data->i2c_addr;
		blinkm_write(client, cmd, NULL);
		blinkm_read(client, cmd, data->args);
		data->i2c_addr = data->args[0];
		break;
	case BLM_SET_TIME_ADJ:
	case BLM_SET_FADE_SPEED:
	case BLM_READ_SCRIPT_LINE:
	case BLM_WRITE_SCRIPT_LINE:
	case BLM_SET_SCRIPT_LR:
	case BLM_SET_ADDR:
	case BLM_GET_FW_VER:
	case BLM_SET_STARTUP_PARAM:
		dev_err(&client->dev,
				"BlinkM: cmd %d not implemented yet.\n", cmd);
		break;
	default:
		dev_err(&client->dev, "BlinkM: unknown command %d\n", cmd);
		mutex_unlock(&data->update_lock);
		return -EINVAL;
	}			/* end switch(cmd) */

	/* transfers done, unlock */
	mutex_unlock(&data->update_lock);
	return 0;
}

static int blinkm_led_common_set(struct led_classdev *led_cdev,
				 enum led_brightness value, int color)
{
	/* led_brightness is 0, 127 or 255 - we just use it here as-is */
	struct blinkm_led *led = cdev_to_blmled(led_cdev);
	struct blinkm_data *data = i2c_get_clientdata(led->i2c_client);

	switch (color) {
	case RED:
		/* bail out if there's no change */
		if (data->next_red == (u8) value)
			return 0;
		data->next_red = (u8) value;
		break;
	case GREEN:
		/* bail out if there's no change */
		if (data->next_green == (u8) value)
			return 0;
		data->next_green = (u8) value;
		break;
	case BLUE:
		/* bail out if there's no change */
		if (data->next_blue == (u8) value)
			return 0;
		data->next_blue = (u8) value;
		break;

	default:
		dev_err(&led->i2c_client->dev, "BlinkM: unknown color.\n");
		return -EINVAL;
	}

	blinkm_transfer_hw(led->i2c_client, BLM_GO_RGB);
	dev_dbg(&led->i2c_client->dev,
			"# DONE # next_red = %d, next_green = %d,"
			" next_blue = %d\n",
			data->next_red, data->next_green,
			data->next_blue);
	return 0;
}

static int blinkm_led_red_set(struct led_classdev *led_cdev,
			       enum led_brightness value)
{
	return blinkm_led_common_set(led_cdev, value, RED);
}

static int blinkm_led_green_set(struct led_classdev *led_cdev,
				 enum led_brightness value)
{
	return blinkm_led_common_set(led_cdev, value, GREEN);
}

static int blinkm_led_blue_set(struct led_classdev *led_cdev,
				enum led_brightness value)
{
	return blinkm_led_common_set(led_cdev, value, BLUE);
}

static void blinkm_init_hw(struct i2c_client *client)
{
	int ret;
	ret = blinkm_transfer_hw(client, BLM_STOP_SCRIPT);
	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
}

static int blinkm_test_run(struct i2c_client *client)
{
	int ret;
	struct blinkm_data *data = i2c_get_clientdata(client);

	data->next_red = 0x01;
	data->next_green = 0x05;
	data->next_blue = 0x10;
	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
	if (ret < 0)
		return ret;
	msleep(2000);

	data->next_red = 0x25;
	data->next_green = 0x10;
	data->next_blue = 0x31;
	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
	if (ret < 0)
		return ret;
	msleep(2000);

	data->next_hue = 0x50;
	data->next_saturation = 0x10;
	data->next_brightness = 0x20;
	ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
	if (ret < 0)
		return ret;
	msleep(2000);

	return 0;
}

/* Return 0 if detection is successful, -ENODEV otherwise */
static int blinkm_detect(struct i2c_client *client, struct i2c_board_info *info)
{
	struct i2c_adapter *adapter = client->adapter;
	int ret;
	int count = 99;
	u8 tmpargs[7];

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
				     | I2C_FUNC_SMBUS_WORD_DATA
				     | I2C_FUNC_SMBUS_WRITE_BYTE))
		return -ENODEV;

	/* Now, we do the remaining detection. Simple for now. */
	/* We might need more guards to protect other i2c slaves */

	/* make sure the blinkM is balanced (read/writes) */
	while (count > 0) {
		ret = blinkm_write(client, BLM_GET_ADDR, NULL);
		if (ret)
			return ret;
		usleep_range(5000, 10000);
		ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
		if (ret)
			return ret;
		usleep_range(5000, 10000);
		if (tmpargs[0] == 0x09)
			count = 0;
		count--;
	}

	/* Step 1: Read BlinkM address back  -  cmd_char 'a' */
	ret = blinkm_write(client, BLM_GET_ADDR, NULL);
	if (ret < 0)
		return ret;
	usleep_range(20000, 30000);	/* allow a small delay */
	ret = blinkm_read(client, BLM_GET_ADDR, tmpargs);
	if (ret < 0)
		return ret;

	if (tmpargs[0] != 0x09) {
		dev_err(&client->dev, "enodev DEV ADDR = 0x%02X\n", tmpargs[0]);
		return -ENODEV;
	}

	strlcpy(info->type, "blinkm", I2C_NAME_SIZE);
	return 0;
}

static int blinkm_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct blinkm_data *data;
	struct blinkm_led *led[3];
	int err, i;
	char blinkm_led_name[28];

	data = devm_kzalloc(&client->dev,
			sizeof(struct blinkm_data), GFP_KERNEL);
	if (!data) {
		err = -ENOMEM;
		goto exit;
	}

	data->i2c_addr = 0x08;
	/* i2c addr  - use fake addr of 0x08 initially (real is 0x09) */
	data->fw_ver = 0xfe;
	/* firmware version - use fake until we read real value
	 * (currently broken - BlinkM confused!) */
	data->script_id = 0x01;
	data->i2c_client = client;

	i2c_set_clientdata(client, data);
	mutex_init(&data->update_lock);

	/* Register sysfs hooks */
	err = sysfs_create_group(&client->dev.kobj, &blinkm_group);
	if (err < 0) {
		dev_err(&client->dev, "couldn't register sysfs group\n");
		goto exit;
	}

	for (i = 0; i < 3; i++) {
		/* RED = 0, GREEN = 1, BLUE = 2 */
		led[i] = &data->blinkm_leds[i];
		led[i]->i2c_client = client;
		led[i]->id = i;
		led[i]->led_cdev.max_brightness = 255;
		led[i]->led_cdev.flags = LED_CORE_SUSPENDRESUME;
		switch (i) {
		case RED:
			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
					 "blinkm-%d-%d-red",
					 client->adapter->nr,
					 client->addr);
			led[i]->led_cdev.name = blinkm_led_name;
			led[i]->led_cdev.brightness_set_blocking =
							blinkm_led_red_set;
			err = led_classdev_register(&client->dev,
						    &led[i]->led_cdev);
			if (err < 0) {
				dev_err(&client->dev,
					"couldn't register LED %s\n",
					led[i]->led_cdev.name);
				goto failred;
			}
			break;
		case GREEN:
			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
					 "blinkm-%d-%d-green",
					 client->adapter->nr,
					 client->addr);
			led[i]->led_cdev.name = blinkm_led_name;
			led[i]->led_cdev.brightness_set_blocking =
							blinkm_led_green_set;
			err = led_classdev_register(&client->dev,
						    &led[i]->led_cdev);
			if (err < 0) {
				dev_err(&client->dev,
					"couldn't register LED %s\n",
					led[i]->led_cdev.name);
				goto failgreen;
			}
			break;
		case BLUE:
			snprintf(blinkm_led_name, sizeof(blinkm_led_name),
					 "blinkm-%d-%d-blue",
					 client->adapter->nr,
					 client->addr);
			led[i]->led_cdev.name = blinkm_led_name;
			led[i]->led_cdev.brightness_set_blocking =
							blinkm_led_blue_set;
			err = led_classdev_register(&client->dev,
						    &led[i]->led_cdev);
			if (err < 0) {
				dev_err(&client->dev,
					"couldn't register LED %s\n",
					led[i]->led_cdev.name);
				goto failblue;
			}
			break;
		}		/* end switch */
	}			/* end for */

	/* Initialize the blinkm */
	blinkm_init_hw(client);

	return 0;

failblue:
	led_classdev_unregister(&led[GREEN]->led_cdev);

failgreen:
	led_classdev_unregister(&led[RED]->led_cdev);

failred:
	sysfs_remove_group(&client->dev.kobj, &blinkm_group);
exit:
	return err;
}

static int blinkm_remove(struct i2c_client *client)
{
	struct blinkm_data *data = i2c_get_clientdata(client);
	int ret = 0;
	int i;

	/* make sure no workqueue entries are pending */
	for (i = 0; i < 3; i++)
		led_classdev_unregister(&data->blinkm_leds[i].led_cdev);

	/* reset rgb */
	data->next_red = 0x00;
	data->next_green = 0x00;
	data->next_blue = 0x00;
	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
	if (ret < 0)
		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");

	/* reset hsb */
	data->next_hue = 0x00;
	data->next_saturation = 0x00;
	data->next_brightness = 0x00;
	ret = blinkm_transfer_hw(client, BLM_FADE_HSB);
	if (ret < 0)
		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");

	/* red fade to off */
	data->next_red = 0xff;
	ret = blinkm_transfer_hw(client, BLM_GO_RGB);
	if (ret < 0)
		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");

	/* off */
	data->next_red = 0x00;
	ret = blinkm_transfer_hw(client, BLM_FADE_RGB);
	if (ret < 0)
		dev_err(&client->dev, "Failure in blinkm_remove ignored. Continuing.\n");

	sysfs_remove_group(&client->dev.kobj, &blinkm_group);
	return 0;
}

static const struct i2c_device_id blinkm_id[] = {
	{"blinkm", 0},
	{}
};

MODULE_DEVICE_TABLE(i2c, blinkm_id);

  /* This is the driver that will be inserted */
static struct i2c_driver blinkm_driver = {
	.class = I2C_CLASS_HWMON,
	.driver = {
		   .name = "blinkm",
		   },
	.probe = blinkm_probe,
	.remove = blinkm_remove,
	.id_table = blinkm_id,
	.detect = blinkm_detect,
	.address_list = normal_i2c,
};

module_i2c_driver(blinkm_driver);

MODULE_AUTHOR("Jan-Simon Moeller <dl9pf@gmx.de>");
MODULE_DESCRIPTION("BlinkM RGB LED driver");
MODULE_LICENSE("GPL");