Free Electrons

Embedded Linux Experts

  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
/*
 * lp5523.c - LP5523, LP55231 LED 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>
 *
 * 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/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/platform_data/leds-lp55xx.h>
#include <linux/slab.h>

#include "leds-lp55xx-common.h"

#define LP5523_PROGRAM_LENGTH		32	/* bytes */
/* Memory is used like this:
   0x00 engine 1 program
   0x10 engine 2 program
   0x20 engine 3 program
   0x30 engine 1 muxing info
   0x40 engine 2 muxing info
   0x50 engine 3 muxing info
*/
#define LP5523_MAX_LEDS			9

/* Registers */
#define LP5523_REG_ENABLE		0x00
#define LP5523_REG_OP_MODE		0x01
#define LP5523_REG_ENABLE_LEDS_MSB	0x04
#define LP5523_REG_ENABLE_LEDS_LSB	0x05
#define LP5523_REG_LED_CTRL_BASE	0x06
#define LP5523_REG_LED_PWM_BASE		0x16
#define LP5523_REG_LED_CURRENT_BASE	0x26
#define LP5523_REG_CONFIG		0x36
#define LP5523_REG_STATUS		0x3A
#define LP5523_REG_RESET		0x3D
#define LP5523_REG_LED_TEST_CTRL	0x41
#define LP5523_REG_LED_TEST_ADC		0x42
#define LP5523_REG_MASTER_FADER_BASE	0x48
#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

/* Bit description in registers */
#define LP5523_ENABLE			0x40
#define LP5523_AUTO_INC			0x40
#define LP5523_PWR_SAVE			0x20
#define LP5523_PWM_PWR_SAVE		0x04
#define LP5523_CP_AUTO			0x18
#define LP5523_AUTO_CLK			0x02

#define LP5523_EN_LEDTEST		0x80
#define LP5523_LEDTEST_DONE		0x80
#define LP5523_RESET			0xFF
#define LP5523_ADC_SHORTCIRC_LIM	80
#define LP5523_EXT_CLK_USED		0x08
#define LP5523_ENG_STATUS_MASK		0x07

#define LP5523_FADER_MAPPING_MASK	0xC0
#define LP5523_FADER_MAPPING_SHIFT	6

/* Memory Page Selection */
#define LP5523_PAGE_ENG1		0
#define LP5523_PAGE_ENG2		1
#define LP5523_PAGE_ENG3		2
#define LP5523_PAGE_MUX1		3
#define LP5523_PAGE_MUX2		4
#define LP5523_PAGE_MUX3		5

/* Program Memory Operations */
#define LP5523_MODE_ENG1_M		0x30	/* Operation Mode Register */
#define LP5523_MODE_ENG2_M		0x0C
#define LP5523_MODE_ENG3_M		0x03
#define LP5523_LOAD_ENG1		0x10
#define LP5523_LOAD_ENG2		0x04
#define LP5523_LOAD_ENG3		0x01

#define LP5523_ENG1_IS_LOADING(mode)	\
	((mode & LP5523_MODE_ENG1_M) == LP5523_LOAD_ENG1)
#define LP5523_ENG2_IS_LOADING(mode)	\
	((mode & LP5523_MODE_ENG2_M) == LP5523_LOAD_ENG2)
#define LP5523_ENG3_IS_LOADING(mode)	\
	((mode & LP5523_MODE_ENG3_M) == LP5523_LOAD_ENG3)

#define LP5523_EXEC_ENG1_M		0x30	/* Enable Register */
#define LP5523_EXEC_ENG2_M		0x0C
#define LP5523_EXEC_ENG3_M		0x03
#define LP5523_EXEC_M			0x3F
#define LP5523_RUN_ENG1			0x20
#define LP5523_RUN_ENG2			0x08
#define LP5523_RUN_ENG3			0x02

#define LED_ACTIVE(mux, led)		(!!(mux & (0x0001 << led)))

enum lp5523_chip_id {
	LP5523,
	LP55231,
};

static int lp5523_init_program_engine(struct lp55xx_chip *chip);

static inline void lp5523_wait_opmode_done(void)
{
	usleep_range(1000, 2000);
}

static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current)
{
	led->led_current = led_current;
	lp55xx_write(led->chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
		led_current);
}

static int lp5523_post_init_device(struct lp55xx_chip *chip)
{
	int ret;

	ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE);
	if (ret)
		return ret;

	/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
	usleep_range(1000, 2000);

	ret = lp55xx_write(chip, LP5523_REG_CONFIG,
			    LP5523_AUTO_INC | LP5523_PWR_SAVE |
			    LP5523_CP_AUTO | LP5523_AUTO_CLK |
			    LP5523_PWM_PWR_SAVE);
	if (ret)
		return ret;

	/* turn on all leds */
	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
	if (ret)
		return ret;

	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
	if (ret)
		return ret;

	return lp5523_init_program_engine(chip);
}

static void lp5523_load_engine(struct lp55xx_chip *chip)
{
	enum lp55xx_engine_index idx = chip->engine_idx;
	static const u8 mask[] = {
		[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
		[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
		[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
	};

	static const u8 val[] = {
		[LP55XX_ENGINE_1] = LP5523_LOAD_ENG1,
		[LP55XX_ENGINE_2] = LP5523_LOAD_ENG2,
		[LP55XX_ENGINE_3] = LP5523_LOAD_ENG3,
	};

	lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]);

	lp5523_wait_opmode_done();
}

static void lp5523_load_engine_and_select_page(struct lp55xx_chip *chip)
{
	enum lp55xx_engine_index idx = chip->engine_idx;
	static const u8 page_sel[] = {
		[LP55XX_ENGINE_1] = LP5523_PAGE_ENG1,
		[LP55XX_ENGINE_2] = LP5523_PAGE_ENG2,
		[LP55XX_ENGINE_3] = LP5523_PAGE_ENG3,
	};

	lp5523_load_engine(chip);

	lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]);
}

static void lp5523_stop_all_engines(struct lp55xx_chip *chip)
{
	lp55xx_write(chip, LP5523_REG_OP_MODE, 0);
	lp5523_wait_opmode_done();
}

static void lp5523_stop_engine(struct lp55xx_chip *chip)
{
	enum lp55xx_engine_index idx = chip->engine_idx;
	static const u8 mask[] = {
		[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
		[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
		[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
	};

	lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], 0);

	lp5523_wait_opmode_done();
}

static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
{
	int i;

	for (i = 0; i < LP5523_MAX_LEDS; i++)
		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
}

static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
{
	int ret;
	u8 mode;
	u8 exec;

	/* stop engine */
	if (!start) {
		lp5523_stop_engine(chip);
		lp5523_turn_off_channels(chip);
		return;
	}

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

	ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
	if (ret)
		return;

	ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
	if (ret)
		return;

	/* change operation mode to RUN only when each engine is loading */
	if (LP5523_ENG1_IS_LOADING(mode)) {
		mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
		exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
	}

	if (LP5523_ENG2_IS_LOADING(mode)) {
		mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
		exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
	}

	if (LP5523_ENG3_IS_LOADING(mode)) {
		mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
		exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
	}

	lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
	lp5523_wait_opmode_done();

	lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
}

static int lp5523_init_program_engine(struct lp55xx_chip *chip)
{
	int i;
	int j;
	int ret;
	u8 status;
	/* one pattern per engine setting LED MUX start and stop addresses */
	static const 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},
	};

	/* hardcode 32 bytes of memory for each engine from program memory */
	ret = lp55xx_write(chip, LP5523_REG_CH1_PROG_START, 0x00);
	if (ret)
		return ret;

	ret = lp55xx_write(chip, LP5523_REG_CH2_PROG_START, 0x10);
	if (ret)
		return ret;

	ret = lp55xx_write(chip, LP5523_REG_CH3_PROG_START, 0x20);
	if (ret)
		return ret;

	/* write LED MUX address space for each engine */
	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
		chip->engine_idx = i;
		lp5523_load_engine_and_select_page(chip);

		for (j = 0; j < LP5523_PROGRAM_LENGTH; j++) {
			ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + j,
					pattern[i - 1][j]);
			if (ret)
				goto out;
		}
	}

	lp5523_run_engine(chip, true);

	/* Let the programs run for couple of ms and check the engine status */
	usleep_range(3000, 6000);
	lp55xx_read(chip, LP5523_REG_STATUS, &status);
	status &= LP5523_ENG_STATUS_MASK;

	if (status != LP5523_ENG_STATUS_MASK) {
		dev_err(&chip->cl->dev,
			"cound not configure LED engine, status = 0x%.2x\n",
			status);
		ret = -1;
	}

out:
	lp5523_stop_all_engines(chip);
	return ret;
}

static int lp5523_update_program_memory(struct lp55xx_chip *chip,
					const u8 *data, size_t size)
{
	u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
	unsigned cmd;
	char c[3];
	int nrchars;
	int ret;
	int offset = 0;
	int i = 0;

	while ((offset < size - 1) && (i < LP5523_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 < LP5523_PROGRAM_LENGTH; i++) {
		ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
		if (ret)
			return -EINVAL;
	}

	return size;

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

static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
{
	const struct firmware *fw = chip->fw;

	if (fw->size > LP5523_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
	 */

	lp5523_load_engine_and_select_page(chip);
	lp5523_update_program_memory(chip, fw->data, fw->size);
}

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)) {
		lp5523_run_engine(chip, true);
		engine->mode = LP55XX_ENGINE_RUN;
	} else if (!strncmp(buf, "load", 4)) {
		lp5523_stop_engine(chip);
		lp5523_load_engine(chip);
		engine->mode = LP55XX_ENGINE_LOAD;
	} else if (!strncmp(buf, "disabled", 8)) {
		lp5523_stop_engine(chip);
		engine->mode = LP55XX_ENGINE_DISABLED;
	}

	mutex_unlock(&chip->lock);

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

static int lp5523_mux_parse(const char *buf, u16 *mux, size_t len)
{
	u16 tmp_mux = 0;
	int i;

	len = min_t(int, len, LP5523_MAX_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_MAX_LEDS; i++)
		pos += sprintf(array + pos, "%x", LED_ACTIVE(led_mux, i));

	array[pos] = '\0';
}

static ssize_t show_engine_leds(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;
	char mux[LP5523_MAX_LEDS + 1];

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

	return sprintf(buf, "%s\n", mux);
}
show_leds(1)
show_leds(2)
show_leds(3)

static int lp5523_load_mux(struct lp55xx_chip *chip, u16 mux, int nr)
{
	struct lp55xx_engine *engine = &chip->engines[nr - 1];
	int ret;
	static const u8 mux_page[] = {
		[LP55XX_ENGINE_1] = LP5523_PAGE_MUX1,
		[LP55XX_ENGINE_2] = LP5523_PAGE_MUX2,
		[LP55XX_ENGINE_3] = LP5523_PAGE_MUX3,
	};

	lp5523_load_engine(chip);

	ret = lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, mux_page[nr]);
	if (ret)
		return ret;

	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM , (u8)(mux >> 8));
	if (ret)
		return ret;

	ret = lp55xx_write(chip, LP5523_REG_PROG_MEM + 1, (u8)(mux));
	if (ret)
		return ret;

	engine->led_mux = mux;
	return 0;
}

static ssize_t store_engine_leds(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];
	u16 mux = 0;
	ssize_t ret;

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

	mutex_lock(&chip->lock);

	chip->engine_idx = nr;
	ret = -EINVAL;

	if (engine->mode != LP55XX_ENGINE_LOAD)
		goto leave;

	if (lp5523_load_mux(chip, mux, nr))
		goto leave;

	ret = len;
leave:
	mutex_unlock(&chip->lock);
	return ret;
}
store_leds(1)
store_leds(2)
store_leds(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;
	lp5523_load_engine_and_select_page(chip);
	ret = lp5523_update_program_memory(chip, buf, len);

	mutex_unlock(&chip->lock);

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

static ssize_t lp5523_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;
	struct lp55xx_platform_data *pdata = chip->pdata;
	int i, ret, pos = 0;
	u8 status, adc, vdd;

	mutex_lock(&chip->lock);

	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
	if (ret < 0)
		goto fail;

	/* Check that ext clock is really in use if requested */
	if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
		if  ((status & LP5523_EXT_CLK_USED) == 0)
			goto fail;
	}

	/* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
	lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
	usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
	if (ret < 0)
		goto fail;

	if (!(status & LP5523_LEDTEST_DONE))
		usleep_range(3000, 6000); /* Was not ready. Wait little bit */

	ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
	if (ret < 0)
		goto fail;

	vdd--;	/* There may be some fluctuation in measurement */

	for (i = 0; i < LP5523_MAX_LEDS; i++) {
		/* Skip non-existing channels */
		if (pdata->led_config[i].led_current == 0)
			continue;

		/* Set default current */
		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
			pdata->led_config[i].led_current);

		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff);
		/* let current stabilize 2 - 4ms before measurements start */
		usleep_range(2000, 4000);
		lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL,
			     LP5523_EN_LEDTEST | i);
		/* ADC conversion time is 2.7 ms typically */
		usleep_range(3000, 6000);
		ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
		if (ret < 0)
			goto fail;

		if (!(status & LP5523_LEDTEST_DONE))
			usleep_range(3000, 6000);/* Was not ready. Wait. */

		ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc);
		if (ret < 0)
			goto fail;

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

		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00);

		/* Restore current */
		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
			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;
}

#define show_fader(nr)						\
static ssize_t show_master_fader##nr(struct device *dev,	\
			    struct device_attribute *attr,	\
			    char *buf)				\
{								\
	return show_master_fader(dev, attr, buf, nr);		\
}

#define store_fader(nr)						\
static ssize_t store_master_fader##nr(struct device *dev,	\
			     struct device_attribute *attr,	\
			     const char *buf, size_t len)	\
{								\
	return store_master_fader(dev, attr, buf, len, nr);	\
}

static ssize_t show_master_fader(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;
	int ret;
	u8 val;

	mutex_lock(&chip->lock);
	ret = lp55xx_read(chip, LP5523_REG_MASTER_FADER_BASE + nr - 1, &val);
	mutex_unlock(&chip->lock);

	if (ret == 0)
		ret = sprintf(buf, "%u\n", val);

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

static ssize_t store_master_fader(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;
	unsigned long val;

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

	if (val > 0xff)
		return -EINVAL;

	mutex_lock(&chip->lock);
	ret = lp55xx_write(chip, LP5523_REG_MASTER_FADER_BASE + nr - 1,
			   (u8)val);
	mutex_unlock(&chip->lock);

	if (ret == 0)
		ret = len;

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

static ssize_t show_master_fader_leds(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 i, ret, pos = 0;
	u8 val;

	mutex_lock(&chip->lock);

	for (i = 0; i < LP5523_MAX_LEDS; i++) {
		ret = lp55xx_read(chip, LP5523_REG_LED_CTRL_BASE + i, &val);
		if (ret)
			goto leave;

		val = (val & LP5523_FADER_MAPPING_MASK)
			>> LP5523_FADER_MAPPING_SHIFT;
		if (val > 3) {
			ret = -EINVAL;
			goto leave;
		}
		buf[pos++] = val + '0';
	}
	buf[pos++] = '\n';
	ret = pos;
leave:
	mutex_unlock(&chip->lock);
	return ret;
}

static ssize_t store_master_fader_leds(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;
	int i, n, ret;
	u8 val;

	n = min_t(int, len, LP5523_MAX_LEDS);

	mutex_lock(&chip->lock);

	for (i = 0; i < n; i++) {
		if (buf[i] >= '0' && buf[i] <= '3') {
			val = (buf[i] - '0') << LP5523_FADER_MAPPING_SHIFT;
			ret = lp55xx_update_bits(chip,
						 LP5523_REG_LED_CTRL_BASE + i,
						 LP5523_FADER_MAPPING_MASK,
						 val);
			if (ret)
				goto leave;
		} else {
			ret = -EINVAL;
			goto leave;
		}
	}
	ret = len;
leave:
	mutex_unlock(&chip->lock);
	return ret;
}

static int lp5523_led_brightness(struct lp55xx_led *led)
{
	struct lp55xx_chip *chip = led->chip;
	int ret;

	mutex_lock(&chip->lock);
	ret = lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
		     led->brightness);
	mutex_unlock(&chip->lock);
	return ret;
}

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_RW(engine1_leds, show_engine1_leds, store_engine1_leds);
static LP55XX_DEV_ATTR_RW(engine2_leds, show_engine2_leds, store_engine2_leds);
static LP55XX_DEV_ATTR_RW(engine3_leds, show_engine3_leds, store_engine3_leds);
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, lp5523_selftest);
static LP55XX_DEV_ATTR_RW(master_fader1, show_master_fader1,
			  store_master_fader1);
static LP55XX_DEV_ATTR_RW(master_fader2, show_master_fader2,
			  store_master_fader2);
static LP55XX_DEV_ATTR_RW(master_fader3, show_master_fader3,
			  store_master_fader3);
static LP55XX_DEV_ATTR_RW(master_fader_leds, show_master_fader_leds,
			  store_master_fader_leds);

static struct attribute *lp5523_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_engine1_leds.attr,
	&dev_attr_engine2_leds.attr,
	&dev_attr_engine3_leds.attr,
	&dev_attr_selftest.attr,
	&dev_attr_master_fader1.attr,
	&dev_attr_master_fader2.attr,
	&dev_attr_master_fader3.attr,
	&dev_attr_master_fader_leds.attr,
	NULL,
};

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

/* Chip specific configurations */
static struct lp55xx_device_config lp5523_cfg = {
	.reset = {
		.addr = LP5523_REG_RESET,
		.val  = LP5523_RESET,
	},
	.enable = {
		.addr = LP5523_REG_ENABLE,
		.val  = LP5523_ENABLE,
	},
	.max_channel  = LP5523_MAX_LEDS,
	.post_init_device   = lp5523_post_init_device,
	.brightness_fn      = lp5523_led_brightness,
	.set_led_current    = lp5523_set_led_current,
	.firmware_cb        = lp5523_firmware_loaded,
	.run_engine         = lp5523_run_engine,
	.dev_attr_group     = &lp5523_group,
};

static int lp5523_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_kzalloc(&client->dev,
			sizeof(*led) * pdata->num_channels, GFP_KERNEL);
	if (!led)
		return -ENOMEM;

	chip->cl = client;
	chip->pdata = pdata;
	chip->cfg = &lp5523_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 lp5523_remove(struct i2c_client *client)
{
	struct lp55xx_led *led = i2c_get_clientdata(client);
	struct lp55xx_chip *chip = led->chip;

	lp5523_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 lp5523_id[] = {
	{ "lp5523",  LP5523 },
	{ "lp55231", LP55231 },
	{ }
};

MODULE_DEVICE_TABLE(i2c, lp5523_id);

#ifdef CONFIG_OF
static const struct of_device_id of_lp5523_leds_match[] = {
	{ .compatible = "national,lp5523", },
	{ .compatible = "ti,lp55231", },
	{},
};

MODULE_DEVICE_TABLE(of, of_lp5523_leds_match);
#endif

static struct i2c_driver lp5523_driver = {
	.driver = {
		.name	= "lp5523x",
		.of_match_table = of_match_ptr(of_lp5523_leds_match),
	},
	.probe		= lp5523_probe,
	.remove		= lp5523_remove,
	.id_table	= lp5523_id,
};

module_i2c_driver(lp5523_driver);

MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
MODULE_DESCRIPTION("LP5523 LED engine");
MODULE_LICENSE("GPL");