summaryrefslogtreecommitdiffstats
path: root/drivers/leds/leds-lp5523.c
blob: 6cb41607519dc0d83f6c5b1b8167ac99d7b8df10 (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
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
/*
 * lp5523.c - LP5523 LED Driver
 *
 * Copyright (C) 2010 Nokia Corporation
 *
 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/ctype.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/leds.h>
#include <linux/leds-lp5523.h>
#include <linux/workqueue.h>
#include <linux/slab.h>

#define LP5523_REG_ENABLE		0x00
#define LP5523_REG_OP_MODE		0x01
#define LP5523_REG_RATIOMETRIC_MSB	0x02
#define LP5523_REG_RATIOMETRIC_LSB	0x03
#define LP5523_REG_ENABLE_LEDS_MSB	0x04
#define LP5523_REG_ENABLE_LEDS_LSB	0x05
#define LP5523_REG_LED_CNTRL_BASE	0x06
#define LP5523_REG_LED_PWM_BASE		0x16
#define LP5523_REG_LED_CURRENT_BASE	0x26
#define LP5523_REG_CONFIG		0x36
#define LP5523_REG_CHANNEL1_PC		0x37
#define LP5523_REG_CHANNEL2_PC		0x38
#define LP5523_REG_CHANNEL3_PC		0x39
#define LP5523_REG_STATUS		0x3a
#define LP5523_REG_GPO			0x3b
#define LP5523_REG_VARIABLE		0x3c
#define LP5523_REG_RESET		0x3d
#define LP5523_REG_TEMP_CTRL		0x3e
#define LP5523_REG_TEMP_READ		0x3f
#define LP5523_REG_TEMP_WRITE		0x40
#define LP5523_REG_LED_TEST_CTRL	0x41
#define LP5523_REG_LED_TEST_ADC		0x42
#define LP5523_REG_ENG1_VARIABLE	0x45
#define LP5523_REG_ENG2_VARIABLE	0x46
#define LP5523_REG_ENG3_VARIABLE	0x47
#define LP5523_REG_MASTER_FADER1	0x48
#define LP5523_REG_MASTER_FADER2	0x49
#define LP5523_REG_MASTER_FADER3	0x4a
#define LP5523_REG_CH1_PROG_START	0x4c
#define LP5523_REG_CH2_PROG_START	0x4d
#define LP5523_REG_CH3_PROG_START	0x4e
#define LP5523_REG_PROG_PAGE_SEL	0x4f
#define LP5523_REG_PROG_MEM		0x50

#define LP5523_CMD_LOAD			0x15 /* 00010101 */
#define LP5523_CMD_RUN			0x2a /* 00101010 */
#define LP5523_CMD_DISABLED		0x00 /* 00000000 */

#define LP5523_ENABLE			0x40
#define LP5523_AUTO_INC			0x40
#define LP5523_PWR_SAVE			0x20
#define LP5523_PWM_PWR_SAVE		0x04
#define LP5523_CP_1			0x08
#define LP5523_CP_1_5			0x10
#define LP5523_CP_AUTO			0x18
#define LP5523_INT_CLK			0x01
#define LP5523_AUTO_CLK			0x02
#define LP5523_EN_LEDTEST		0x80
#define LP5523_LEDTEST_DONE		0x80

#define LP5523_DEFAULT_CURRENT		50 /* microAmps */
#define LP5523_PROGRAM_LENGTH		32 /* in bytes */
#define LP5523_PROGRAM_PAGES		6
#define LP5523_ADC_SHORTCIRC_LIM	80

#define LP5523_LEDS			9
#define LP5523_ENGINES			3

#define LP5523_ENG_MASK_BASE		0x30 /* 00110000 */

#define LP5523_ENG_STATUS_MASK          0x07 /* 00000111 */

#define LP5523_IRQ_FLAGS                IRQF_TRIGGER_FALLING

#define LP5523_EXT_CLK_USED		0x08

#define LED_ACTIVE(mux, led)		(!!(mux & (0x0001 << led)))
#define SHIFT_MASK(id)			(((id) - 1) * 2)

struct lp5523_engine {
	const struct attribute_group *attributes;
	int		id;
	u8		mode;
	u8		prog_page;
	u8		mux_page;
	u16		led_mux;
	u8		engine_mask;
};

struct lp5523_led {
	int			id;
	u8			chan_nr;
	u8			led_current;
	u8			max_current;
	struct led_classdev     cdev;
	struct work_struct	brightness_work;
	u8			brightness;
};

struct lp5523_chip {
	struct mutex		lock; /* Serialize control */
	struct i2c_client	*client;
	struct lp5523_engine	engines[LP5523_ENGINES];
	struct lp5523_led	leds[LP5523_LEDS];
	struct lp5523_platform_data *pdata;
	u8			num_channels;
	u8			num_leds;
};

static inline struct lp5523_led *cdev_to_led(struct led_classdev *cdev)
{
	return container_of(cdev, struct lp5523_led, cdev);
}

static inline struct lp5523_chip *engine_to_lp5523(struct lp5523_engine *engine)
{
	return container_of(engine, struct lp5523_chip,
			    engines[engine->id - 1]);
}

static inline struct lp5523_chip *led_to_lp5523(struct lp5523_led *led)
{
	return container_of(led, struct lp5523_chip,
			    leds[led->id]);
}

static int lp5523_set_mode(struct lp5523_engine *engine, u8 mode);
static int lp5523_set_engine_mode(struct lp5523_engine *engine, u8 mode);
static int lp5523_load_program(struct lp5523_engine *engine, u8 *pattern);

static void lp5523_led_brightness_work(struct work_struct *work);

static int lp5523_write(struct i2c_client *client, u8 reg, u8 value)
{
	return i2c_smbus_write_byte_data(client, reg, value);
}

static int lp5523_read(struct i2c_client *client, u8 reg, u8 *buf)
{
	s32 ret = i2c_smbus_read_byte_data(client, reg);

	if (ret < 0)
		return -EIO;

	*buf = ret;
	return 0;
}

static int lp5523_detect(struct i2c_client *client)
{
	int ret;
	u8 buf;

	ret = lp5523_write(client, LP5523_REG_ENABLE, 0x40);
	if (ret)
		return ret;
	ret = lp5523_read(client, LP5523_REG_ENABLE, &buf);
	if (ret)
		return ret;
	if (buf == 0x40)
		return 0;
	else
		return -ENODEV;
}

static int lp5523_configure(struct i2c_client *client)
{
	struct lp5523_chip *chip = i2c_get_clientdata(client);
	int ret = 0;
	u8 status;

	/* one pattern per engine setting led mux start and stop addresses */
	u8 pattern[][LP5523_PROGRAM_LENGTH] =  {
		{ 0x9c, 0x30, 0x9c, 0xb0, 0x9d, 0x80, 0xd8, 0x00, 0},
		{ 0x9c, 0x40, 0x9c, 0xc0, 0x9d, 0x80, 0xd8, 0x00, 0},
		{ 0x9c, 0x50, 0x9c, 0xd0, 0x9d, 0x80, 0xd8, 0x00, 0},
	};

	ret |= lp5523_write(client, LP5523_REG_ENABLE, LP5523_ENABLE);
	/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
	usleep_range(1000, 2000);

	ret |= lp5523_write(client, LP5523_REG_CONFIG,
			    LP5523_AUTO_INC | LP5523_PWR_SAVE |
			    LP5523_CP_AUTO | LP5523_AUTO_CLK |
			    LP5523_PWM_PWR_SAVE);

	/* turn on all leds */
	ret |= lp5523_write(client, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
	ret |= lp5523_write(client, LP5523_REG_ENABLE_LEDS_LSB, 0xff);

	/* hardcode 32 bytes of memory for each engine from program memory */
	ret |= lp5523_write(client, LP5523_REG_CH1_PROG_START, 0x00);
	ret |= lp5523_write(client, LP5523_REG_CH2_PROG_START, 0x10);
	ret |= lp5523_write(client, LP5523_REG_CH3_PROG_START, 0x20);

	/* write led mux address space for each channel */
	ret |= lp5523_load_program(&chip->engines[0], pattern[0]);
	ret |= lp5523_load_program(&chip->engines[1], pattern[1]);
	ret |= lp5523_load_program(&chip->engines[2], pattern[2]);

	if (ret) {
		dev_err(&client->dev, "could not load mux programs\n");
		return -1;
	}

	/* set all engines exec state and mode to run 00101010 */
	ret |= lp5523_write(client, LP5523_REG_ENABLE,
			    (LP5523_CMD_RUN | LP5523_ENABLE));

	ret |= lp5523_write(client, LP5523_REG_OP_MODE, LP5523_CMD_RUN);

	if (ret) {
		dev_err(&client->dev, "could not start mux programs\n");
		return -1;
	}

	/* Let the programs run for couple of ms and check the engine status */
	usleep_range(3000, 6000);
	lp5523_read(client, LP5523_REG_STATUS, &status);
	status &= LP5523_ENG_STATUS_MASK;

	if (status == LP5523_ENG_STATUS_MASK) {
		dev_dbg(&client->dev, "all engines configured\n");
	} else {
		dev_info(&client->dev, "status == %x\n", status);
		dev_err(&client->dev, "cound not configure LED engine\n");
		return -1;
	}

	dev_info(&client->dev, "disabling engines\n");

	ret |= lp5523_write(client, LP5523_REG_OP_MODE, LP5523_CMD_DISABLED);

	return ret;
}

static int lp5523_set_engine_mode(struct lp5523_engine *engine, u8 mode)
{
	struct lp5523_chip *chip = engine_to_lp5523(engine);
	struct i2c_client *client = chip->client;
	int ret;
	u8 engine_state;

	ret = lp5523_read(client, LP5523_REG_OP_MODE, &engine_state);
	if (ret)
		goto fail;

	engine_state &= ~(engine->engine_mask);

	/* set mode only for this engine */
	mode &= engine->engine_mask;

	engine_state |= mode;

	ret |= lp5523_write(client, LP5523_REG_OP_MODE, engine_state);
fail:
	return ret;
}

static int lp5523_load_mux(struct lp5523_engine *engine, u16 mux)
{
	struct lp5523_chip *chip = engine_to_lp5523(engine);
	struct i2c_client *client = chip->client;
	int ret = 0;

	ret |= lp5523_set_engine_mode(engine, LP5523_CMD_LOAD);

	ret |= lp5523_write(client, LP5523_REG_PROG_PAGE_SEL, engine->mux_page);
	ret |= lp5523_write(client, LP5523_REG_PROG_MEM,
			    (u8)(mux >> 8));
	ret |= lp5523_write(client, LP5523_REG_PROG_MEM + 1, (u8)(mux));
	engine->led_mux = mux;

	return ret;
}

static int lp5523_load_program(struct lp5523_engine *engine, u8 *pattern)
{
	struct lp5523_chip *chip = engine_to_lp5523(engine);
	struct i2c_client *client = chip->client;

	int ret = 0;

	ret |= lp5523_set_engine_mode(engine, LP5523_CMD_LOAD);

	ret |= lp5523_write(client, LP5523_REG_PROG_PAGE_SEL,
			    engine->prog_page);
	ret |= i2c_smbus_write_i2c_block_data(client, LP5523_REG_PROG_MEM,
					      LP5523_PROGRAM_LENGTH, pattern);

	return ret;
}

static int lp5523_run_program(struct lp5523_engine *engine)
{
	struct lp5523_chip *chip = engine_to_lp5523(engine);
	struct i2c_client *client = chip->client;
	int ret;

	ret = lp5523_write(client, LP5523_REG_ENABLE,
					LP5523_CMD_RUN | LP5523_ENABLE);
	if (ret)
		goto fail;

	ret = lp5523_set_engine_mode(engine, LP5523_CMD_RUN);
fail:
	return ret;
}

static int lp5523_mux_parse(const char *buf, u16 *mux, size_t len)
{
	int i;
	u16 tmp_mux = 0;
	len = len < LP5523_LEDS ? len : LP5523_LEDS;
	for (i = 0; i < len; i++) {
		switch (buf[i]) {
		case '1':
			tmp_mux |= (1 << i);
			break;
		case '0':
			break;
		case '\n':
			i = len;
			break;
		default:
			return -1;
		}
	}
	*mux = tmp_mux;

	return 0;
}

static void lp5523_mux_to_array(u16 led_mux, char *array)
{
	int i, pos = 0;
	for (i = 0; i < LP5523_LEDS; i++)
		pos += sprintf(array + pos, "%x", LED_ACTIVE(led_mux, i));

	array[pos] = '\0';
}

/*--------------------------------------------------------------*/
/*			Sysfs interface				*/
/*--------------------------------------------------------------*/

static ssize_t show_engine_leds(struct device *dev,
			    struct device_attribute *attr,
			    char *buf, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lp5523_chip *chip = i2c_get_clientdata(client);
	char mux[LP5523_LEDS + 1];

	lp5523_mux_to_array(chip->engines[nr - 1].led_mux, mux);

	return sprintf(buf, "%s\n", mux);
}

#define show_leds(nr)							\
static ssize_t show_engine##nr##_leds(struct device *dev,		\
			    struct device_attribute *attr,		\
			    char *buf)					\
{									\
	return show_engine_leds(dev, attr, buf, nr);			\
}
show_leds(1)
show_leds(2)
show_leds(3)

static ssize_t store_engine_leds(struct device *dev,
			     struct device_attribute *attr,
			     const char *buf, size_t len, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lp5523_chip *chip = i2c_get_clientdata(client);
	u16 mux = 0;

	if (lp5523_mux_parse(buf, &mux, len))
		return -EINVAL;

	if (lp5523_load_mux(&chip->engines[nr - 1], mux))
		return -EINVAL;

	return len;
}

#define store_leds(nr)						\
static ssize_t store_engine##nr##_leds(struct device *dev,	\
			     struct device_attribute *attr,	\
			     const char *buf, size_t len)	\
{								\
	return store_engine_leds(dev, attr, buf, len, nr);	\
}
store_leds(1)
store_leds(2)
store_leds(3)

static ssize_t lp5523_selftest(struct device *dev,
			       struct device_attribute *attr,
			       char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lp5523_chip *chip = i2c_get_clientdata(client);
	int i, ret, pos = 0;
	int led = 0;
	u8 status, adc, vdd;

	mutex_lock(&chip->lock);

	ret = lp5523_read(chip->client, LP5523_REG_STATUS, &status);
	if (ret < 0)
		goto fail;

	/* Check that ext clock is really in use if requested */
	if ((chip->pdata) && (chip->pdata->clock_mode == LP5523_CLOCK_EXT))
		if  ((status & LP5523_EXT_CLK_USED) == 0)
			goto fail;

	/* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
	lp5523_write(chip->client, LP5523_REG_LED_TEST_CTRL,
				    LP5523_EN_LEDTEST | 16);
	usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
	ret = lp5523_read(chip->client, LP5523_REG_STATUS, &status);
	if (!(status & LP5523_LEDTEST_DONE))
		usleep_range(3000, 6000); /* Was not ready. Wait little bit */

	ret |= lp5523_read(chip->client, LP5523_REG_LED_TEST_ADC, &vdd);
	vdd--;	/* There may be some fluctuation in measurement */

	for (i = 0; i < LP5523_LEDS; i++) {
		/* Skip non-existing channels */
		if (chip->pdata->led_config[i].led_current == 0)
			continue;

		/* Set default current */
		lp5523_write(chip->client,
			LP5523_REG_LED_CURRENT_BASE + i,
			chip->pdata->led_config[i].led_current);

		lp5523_write(chip->client, LP5523_REG_LED_PWM_BASE + i, 0xff);
		/* let current stabilize 2 - 4ms before measurements start */
		usleep_range(2000, 4000);
		lp5523_write(chip->client,
			     LP5523_REG_LED_TEST_CTRL,
			     LP5523_EN_LEDTEST | i);
		/* ADC conversion time is 2.7 ms typically */
		usleep_range(3000, 6000);
		ret = lp5523_read(chip->client, LP5523_REG_STATUS, &status);
		if (!(status & LP5523_LEDTEST_DONE))
			usleep_range(3000, 6000);/* Was not ready. Wait. */
		ret |= lp5523_read(chip->client, LP5523_REG_LED_TEST_ADC, &adc);

		if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
			pos += sprintf(buf + pos, "LED %d FAIL\n", i);

		lp5523_write(chip->client, LP5523_REG_LED_PWM_BASE + i, 0x00);

		/* Restore current */
		lp5523_write(chip->client,
			LP5523_REG_LED_CURRENT_BASE + i,
			chip->leds[led].led_current);
		led++;
	}
	if (pos == 0)
		pos = sprintf(buf, "OK\n");
	goto release_lock;
fail:
	pos = sprintf(buf, "FAIL\n");

release_lock:
	mutex_unlock(&chip->lock);

	return pos;
}

static void lp5523_set_brightness(struct led_classdev *cdev,
			     enum led_brightness brightness)
{
	struct lp5523_led *led = cdev_to_led(cdev);

	led->brightness = (u8)brightness;

	schedule_work(&led->brightness_work);
}

static void lp5523_led_brightness_work(struct work_struct *work)
{
	struct lp5523_led *led = container_of(work,
					      struct lp5523_led,
					      brightness_work);
	struct lp5523_chip *chip = led_to_lp5523(led);
	struct i2c_client *client = chip->client;

	mutex_lock(&chip->lock);

	lp5523_write(client, LP5523_REG_LED_PWM_BASE + led->chan_nr,
		     led->brightness);

	mutex_unlock(&chip->lock);
}

static int lp5523_do_store_load(struct lp5523_engine *engine,
				const char *buf, size_t len)
{
	struct lp5523_chip *chip = engine_to_lp5523(engine);
	struct i2c_client *client = chip->client;
	int  ret, nrchars, offset = 0, i = 0;
	char c[3];
	unsigned cmd;
	u8 pattern[LP5523_PROGRAM_LENGTH] = {0};

	while ((offset < len - 1) && (i < LP5523_PROGRAM_LENGTH)) {
		/* separate sscanfs because length is working only for %s */
		ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
		ret = sscanf(c, "%2x", &cmd);
		if (ret != 1)
			goto fail;
		pattern[i] = (u8)cmd;

		offset += nrchars;
		i++;
	}

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

	mutex_lock(&chip->lock);

	ret = lp5523_load_program(engine, pattern);
	mutex_unlock(&chip->lock);

	if (ret) {
		dev_err(&client->dev, "failed loading pattern\n");
		return ret;
	}

	return len;
fail:
	dev_err(&client->dev, "wrong pattern format\n");
	return -EINVAL;
}

static ssize_t store_engine_load(struct device *dev,
				     struct device_attribute *attr,
				     const char *buf, size_t len, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lp5523_chip *chip = i2c_get_clientdata(client);
	return lp5523_do_store_load(&chip->engines[nr - 1], buf, len);
}

#define store_load(nr)							\
static ssize_t store_engine##nr##_load(struct device *dev,		\
				     struct device_attribute *attr,	\
				     const char *buf, size_t len)	\
{									\
	return store_engine_load(dev, attr, buf, len, nr);		\
}
store_load(1)
store_load(2)
store_load(3)

static ssize_t show_engine_mode(struct device *dev,
				struct device_attribute *attr,
				char *buf, int nr)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct lp5523_chip *chip = i2c_get_clientdata(client);
	switch (chip->engines[nr - 1].mode) {
	case LP5523_CMD_RUN:
		return sprintf(buf, "run\n");
	case LP5523_CMD_LOAD:
		return sprintf(buf, "load\n");
	case LP5523_CMD_DISABLED:
		return sprintf(buf, "disabled\n");
	default:
		return sprintf(buf, "disabled\n");
	}
}

#define show_mode(nr)							\
static ssize_t show_engine##nr##_mode(struct device *dev,		\
				    struct device_attribute *attr,	\
				    char *buf)				\
{									\
	return show_engine_mode(dev, attr, buf, nr);			\
}
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 i2c_client *client = to_i2c_client(dev);
	struct lp5523_chip *chip = i2c_get_clientdata(client);
	struct lp5523_engine *engine = &chip->engines[nr - 1];
	mutex_lock(&chip->lock);

	if (!strncmp(buf, "run", 3))
		lp5523_set_mode(engine, LP5523_CMD_RUN);
	else if (!strncmp(buf, "load", 4))
		lp5523_set_mode(engine, LP5523_CMD_LOAD);
	else if (!strncmp(buf, "disabled", 8))
		lp5523_set_mode(engine, LP5523_CMD_DISABLED);

	mutex_unlock(&chip->lock);
	return len;
}

#define store_mode(nr)							\
static ssize_t store_engine##nr##_mode(struct device *dev,		\
				     struct device_attribute *attr,	\
				     const char *buf, size_t len)	\
{									\
	return store_engine_mode(dev, attr, buf, len, nr);		\
}
store_mode(1)
store_mode(2)
store_mode(3)

static ssize_t show_max_current(struct device *dev,
			    struct device_attribute *attr,
			    char *buf)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct lp5523_led *led = cdev_to_led(led_cdev);

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

static ssize_t show_current(struct device *dev,
			    struct device_attribute *attr,
			    char *buf)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct lp5523_led *led = cdev_to_led(led_cdev);

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

static ssize_t store_current(struct device *dev,
			     struct device_attribute *attr,
			     const char *buf, size_t len)
{
	struct led_classdev *led_cdev = dev_get_drvdata(dev);
	struct lp5523_led *led = cdev_to_led(led_cdev);
	struct lp5523_chip *chip = led_to_lp5523(led);
	ssize_t ret;
	unsigned long curr;

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

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

	mutex_lock(&chip->lock);
	ret = lp5523_write(chip->client,
			LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
			(u8)curr);
	mutex_unlock(&chip->lock);

	if (ret < 0)
		return ret;

	led->led_current = (u8)curr;

	return len;
}

/* led class device attributes */
static DEVICE_ATTR(led_current, S_IRUGO | S_IWUGO, show_current, store_current);
static DEVICE_ATTR(max_current, S_IRUGO , show_max_current, NULL);

static struct attribute *lp5523_led_attributes[] = {
	&dev_attr_led_current.attr,
	&dev_attr_max_current.attr,
	NULL,
};

static struct attribute_group lp5523_led_attribute_group = {
	.attrs = lp5523_led_attributes
};

/* device attributes */
static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUGO,
		   show_engine1_mode, store_engine1_mode);
static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUGO,
		   show_engine2_mode, store_engine2_mode);
static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUGO,
		   show_engine3_mode, store_engine3_mode);
static DEVICE_ATTR(engine1_leds, S_IRUGO | S_IWUGO,
		   show_engine1_leds, store_engine1_leds);
static DEVICE_ATTR(engine2_leds, S_IRUGO | S_IWUGO,
		   show_engine2_leds, store_engine2_leds);
static DEVICE_ATTR(engine3_leds, S_IRUGO | S_IWUGO,
		   show_engine3_leds, store_engine3_leds);
static DEVICE_ATTR(engine1_load, S_IWUGO, NULL, store_engine1_load);
static DEVICE_ATTR(engine2_load, S_IWUGO, NULL, store_engine2_load);
static DEVICE_ATTR(engine3_load, S_IWUGO, NULL, store_engine3_load);
static DEVICE_ATTR(selftest, S_IRUGO, lp5523_selftest, NULL);

static struct attribute *lp5523_attributes[] = {
	&dev_attr_engine1_mode.attr,
	&dev_attr_engine2_mode.attr,
	&dev_attr_engine3_mode.attr,
	&dev_attr_selftest.attr,
	NULL
};

static struct attribute *lp5523_engine1_attributes[] = {
	&dev_attr_engine1_load.attr,
	&dev_attr_engine1_leds.attr,
	NULL
};

static struct attribute *lp5523_engine2_attributes[] = {
	&dev_attr_engine2_load.attr,
	&dev_attr_engine2_leds.attr,
	NULL
};

static struct attribute *lp5523_engine3_attributes[] = {
	&dev_attr_engine3_load.attr,
	&dev_attr_engine3_leds.attr,
	NULL
};

static const struct attribute_group lp5523_group = {
	.attrs = lp5523_attributes,
};

static const struct attribute_group lp5523_engine_group[] = {
	{.attrs = lp5523_engine1_attributes },
	{.attrs = lp5523_engine2_attributes },
	{.attrs = lp5523_engine3_attributes },
};

static int lp5523_register_sysfs(struct i2c_client *client)
{
	struct device *dev = &client->dev;
	int ret;

	ret = sysfs_create_group(&dev->kobj, &lp5523_group);
	if (ret < 0)
		return ret;

	return 0;
}

static void lp5523_unregister_sysfs(struct i2c_client *client)
{
	struct lp5523_chip *chip = i2c_get_clientdata(client);
	struct device *dev = &client->dev;
	int i;

	sysfs_remove_group(&dev->kobj, &lp5523_group);

	for (i = 0; i < ARRAY_SIZE(chip->engines); i++)
		if (chip->engines[i].mode == LP5523_CMD_LOAD)
			sysfs_remove_group(&dev->kobj, &lp5523_engine_group[i]);

	for (i = 0; i < chip->num_leds; i++)
		sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
				&lp5523_led_attribute_group);
}

/*--------------------------------------------------------------*/
/*			Set chip operating mode			*/
/*--------------------------------------------------------------*/
static int lp5523_set_mode(struct lp5523_engine *engine, u8 mode)
{
	/*  engine to chip */
	struct lp5523_chip *chip = engine_to_lp5523(engine);
	struct i2c_client *client = chip->client;
	struct device *dev = &client->dev;
	int ret = 0;

	/* if in that mode already do nothing, except for run */
	if (mode == engine->mode && mode != LP5523_CMD_RUN)
		return 0;

	if (mode == LP5523_CMD_RUN) {
		ret = lp5523_run_program(engine);
	} else if (mode == LP5523_CMD_LOAD) {
		lp5523_set_engine_mode(engine, LP5523_CMD_DISABLED);
		lp5523_set_engine_mode(engine, LP5523_CMD_LOAD);

		ret = sysfs_create_group(&dev->kobj, engine->attributes);
		if (ret)
			return ret;
	} else if (mode == LP5523_CMD_DISABLED) {
		lp5523_set_engine_mode(engine, LP5523_CMD_DISABLED);
	}

	/* remove load attribute from sysfs if not in load mode */
	if (engine->mode == LP5523_CMD_LOAD && mode != LP5523_CMD_LOAD)
		sysfs_remove_group(&dev->kobj, engine->attributes);

	engine->mode = mode;

	return ret;
}

/*--------------------------------------------------------------*/
/*			Probe, Attach, Remove			*/
/*--------------------------------------------------------------*/
static int __init lp5523_init_engine(struct lp5523_engine *engine, int id)
{
	if (id < 1 || id > LP5523_ENGINES)
		return -1;
	engine->id = id;
	engine->engine_mask = LP5523_ENG_MASK_BASE >> SHIFT_MASK(id);
	engine->prog_page = id - 1;
	engine->mux_page = id + 2;
	engine->attributes = &lp5523_engine_group[id - 1];

	return 0;
}

static int __init lp5523_init_led(struct lp5523_led *led, struct device *dev,
			   int chan, struct lp5523_platform_data *pdata)
{
	char name[32];
	int res;

	if (chan >= LP5523_LEDS)
		return -EINVAL;

	if (pdata->led_config[chan].led_current) {
		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 >= LP5523_LEDS) {
			dev_err(dev, "Use channel numbers between 0 and %d\n",
				LP5523_LEDS - 1);
			return -EINVAL;
		}

		snprintf(name, sizeof(name), "%s:channel%d",
			pdata->label ?: "lp5523", chan);

		led->cdev.name = name;
		led->cdev.brightness_set = lp5523_set_brightness;
		res = led_classdev_register(dev, &led->cdev);
		if (res < 0) {
			dev_err(dev, "couldn't register led on channel %d\n",
				chan);
			return res;
		}
		res = sysfs_create_group(&led->cdev.dev->kobj,
				&lp5523_led_attribute_group);
		if (res < 0) {
			dev_err(dev, "couldn't register current attribute\n");
			led_classdev_unregister(&led->cdev);
			return res;
		}
	} else {
		led->led_current = 0;
	}
	return 0;
}

static struct i2c_driver lp5523_driver;

static int lp5523_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct lp5523_chip		*chip;
	struct lp5523_platform_data	*pdata;
	int ret, i, led;

	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
	if (!chip)
		return -ENOMEM;

	i2c_set_clientdata(client, chip);
	chip->client = client;

	pdata = client->dev.platform_data;

	if (!pdata) {
		dev_err(&client->dev, "no platform data\n");
		ret = -EINVAL;
		goto fail1;
	}

	mutex_init(&chip->lock);

	chip->pdata   = pdata;

	if (pdata->setup_resources) {
		ret = pdata->setup_resources();
		if (ret < 0)
			goto fail1;
	}

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

	lp5523_write(client, LP5523_REG_RESET, 0xff);
	usleep_range(10000, 20000); /*
				     * Exact value is not available. 10 - 20ms
				     * appears to be enough for reset.
				     */
	ret = lp5523_detect(client);
	if (ret)
		goto fail2;

	dev_info(&client->dev, "LP5523 Programmable led chip found\n");

	/* Initialize engines */
	for (i = 0; i < ARRAY_SIZE(chip->engines); i++) {
		ret = lp5523_init_engine(&chip->engines[i], i + 1);
		if (ret) {
			dev_err(&client->dev, "error initializing engine\n");
			goto fail2;
		}
	}
	ret = lp5523_configure(client);
	if (ret < 0) {
		dev_err(&client->dev, "error configuring chip\n");
		goto fail2;
	}

	/* Initialize leds */
	chip->num_channels = pdata->num_channels;
	chip->num_leds = 0;
	led = 0;
	for (i = 0; i < pdata->num_channels; i++) {
		/* Do not initialize channels that are not connected */
		if (pdata->led_config[i].led_current == 0)
			continue;

		ret = lp5523_init_led(&chip->leds[led], &client->dev, i, pdata);
		if (ret) {
			dev_err(&client->dev, "error initializing leds\n");
			goto fail3;
		}
		chip->num_leds++;

		chip->leds[led].id = led;
		/* Set LED current */
		lp5523_write(client,
			  LP5523_REG_LED_CURRENT_BASE + chip->leds[led].chan_nr,
			  chip->leds[led].led_current);

		INIT_WORK(&(chip->leds[led].brightness_work),
			lp5523_led_brightness_work);

		led++;
	}

	ret = lp5523_register_sysfs(client);
	if (ret) {
		dev_err(&client->dev, "registering sysfs failed\n");
		goto fail3;
	}
	return ret;
fail3:
	for (i = 0; i < chip->num_leds; i++) {
		led_classdev_unregister(&chip->leds[i].cdev);
		cancel_work_sync(&chip->leds[i].brightness_work);
	}
fail2:
	if (pdata->enable)
		pdata->enable(0);
	if (pdata->release_resources)
		pdata->release_resources();
fail1:
	kfree(chip);
	return ret;
}

static int lp5523_remove(struct i2c_client *client)
{
	struct lp5523_chip *chip = i2c_get_clientdata(client);
	int i;

	lp5523_unregister_sysfs(client);

	for (i = 0; i < chip->num_leds; i++) {
		led_classdev_unregister(&chip->leds[i].cdev);
		cancel_work_sync(&chip->leds[i].brightness_work);
	}

	if (chip->pdata->enable)
		chip->pdata->enable(0);
	if (chip->pdata->release_resources)
		chip->pdata->release_resources();
	kfree(chip);
	return 0;
}

static const struct i2c_device_id lp5523_id[] = {
	{ "lp5523", 0 },
	{ }
};

MODULE_DEVICE_TABLE(i2c, lp5523_id);

static struct i2c_driver lp5523_driver = {
	.driver = {
		.name	= "lp5523",
	},
	.probe		= lp5523_probe,
	.remove		= lp5523_remove,
	.id_table	= lp5523_id,
};

static int __init lp5523_init(void)
{
	int ret;

	ret = i2c_add_driver(&lp5523_driver);

	if (ret < 0)
		printk(KERN_ALERT "Adding lp5523 driver failed\n");

	return ret;
}

static void __exit lp5523_exit(void)
{
	i2c_del_driver(&lp5523_driver);
}

module_init(lp5523_init);
module_exit(lp5523_exit);

MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
MODULE_DESCRIPTION("LP5523 LED engine");
MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud