summaryrefslogtreecommitdiffstats
path: root/drivers/media/i2c/et8ek8/et8ek8_driver.c
blob: ff9bb9fc97dd851e459446d65f7ca5db7dcfa272 (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
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
// SPDX-License-Identifier: GPL-2.0-only
/*
 * et8ek8_driver.c
 *
 * Copyright (C) 2008 Nokia Corporation
 *
 * Contact: Sakari Ailus <sakari.ailus@iki.fi>
 *          Tuukka Toivonen <tuukkat76@gmail.com>
 *          Pavel Machek <pavel@ucw.cz>
 *
 * Based on code from Toni Leinonen <toni.leinonen@offcode.fi>.
 *
 * This driver is based on the Micron MT9T012 camera imager driver
 * (C) Texas Instruments.
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <linux/sort.h>
#include <linux/v4l2-mediabus.h>

#include <media/media-entity.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>
#include <media/v4l2-subdev.h>

#include "et8ek8_reg.h"

#define ET8EK8_NAME		"et8ek8"
#define ET8EK8_PRIV_MEM_SIZE	128
#define ET8EK8_MAX_MSG		8

struct et8ek8_sensor {
	struct v4l2_subdev subdev;
	struct media_pad pad;
	struct v4l2_mbus_framefmt format;
	struct gpio_desc *reset;
	struct regulator *vana;
	struct clk *ext_clk;
	u32 xclk_freq;

	u16 version;

	struct v4l2_ctrl_handler ctrl_handler;
	struct v4l2_ctrl *exposure;
	struct v4l2_ctrl *pixel_rate;
	struct et8ek8_reglist *current_reglist;

	u8 priv_mem[ET8EK8_PRIV_MEM_SIZE];

	struct mutex power_lock;
	int power_count;
};

#define to_et8ek8_sensor(sd)	container_of(sd, struct et8ek8_sensor, subdev)

enum et8ek8_versions {
	ET8EK8_REV_1 = 0x0001,
	ET8EK8_REV_2,
};

/*
 * This table describes what should be written to the sensor register
 * for each gain value. The gain(index in the table) is in terms of
 * 0.1EV, i.e. 10 indexes in the table give 2 time more gain [0] in
 * the *analog gain, [1] in the digital gain
 *
 * Analog gain [dB] = 20*log10(regvalue/32); 0x20..0x100
 */
static struct et8ek8_gain {
	u16 analog;
	u16 digital;
} const et8ek8_gain_table[] = {
	{ 32,    0},  /* x1 */
	{ 34,    0},
	{ 37,    0},
	{ 39,    0},
	{ 42,    0},
	{ 45,    0},
	{ 49,    0},
	{ 52,    0},
	{ 56,    0},
	{ 60,    0},
	{ 64,    0},  /* x2 */
	{ 69,    0},
	{ 74,    0},
	{ 79,    0},
	{ 84,    0},
	{ 91,    0},
	{ 97,    0},
	{104,    0},
	{111,    0},
	{119,    0},
	{128,    0},  /* x4 */
	{137,    0},
	{147,    0},
	{158,    0},
	{169,    0},
	{181,    0},
	{194,    0},
	{208,    0},
	{223,    0},
	{239,    0},
	{256,    0},  /* x8 */
	{256,   73},
	{256,  152},
	{256,  236},
	{256,  327},
	{256,  424},
	{256,  528},
	{256,  639},
	{256,  758},
	{256,  886},
	{256, 1023},  /* x16 */
};

/* Register definitions */
#define REG_REVISION_NUMBER_L	0x1200
#define REG_REVISION_NUMBER_H	0x1201

#define PRIV_MEM_START_REG	0x0008
#define PRIV_MEM_WIN_SIZE	8

#define ET8EK8_I2C_DELAY	3	/* msec delay b/w accesses */

#define USE_CRC			1

/*
 * Register access helpers
 *
 * Read a 8/16/32-bit i2c register.  The value is returned in 'val'.
 * Returns zero if successful, or non-zero otherwise.
 */
static int et8ek8_i2c_read_reg(struct i2c_client *client, u16 data_length,
			       u16 reg, u32 *val)
{
	int r;
	struct i2c_msg msg;
	unsigned char data[4];

	if (!client->adapter)
		return -ENODEV;
	if (data_length != ET8EK8_REG_8BIT && data_length != ET8EK8_REG_16BIT)
		return -EINVAL;

	msg.addr = client->addr;
	msg.flags = 0;
	msg.len = 2;
	msg.buf = data;

	/* high byte goes out first */
	data[0] = (u8) (reg >> 8);
	data[1] = (u8) (reg & 0xff);
	r = i2c_transfer(client->adapter, &msg, 1);
	if (r < 0)
		goto err;

	msg.len = data_length;
	msg.flags = I2C_M_RD;
	r = i2c_transfer(client->adapter, &msg, 1);
	if (r < 0)
		goto err;

	*val = 0;
	/* high byte comes first */
	if (data_length == ET8EK8_REG_8BIT)
		*val = data[0];
	else
		*val = (data[1] << 8) + data[0];

	return 0;

err:
	dev_err(&client->dev, "read from offset 0x%x error %d\n", reg, r);

	return r;
}

static void et8ek8_i2c_create_msg(struct i2c_client *client, u16 len, u16 reg,
				  u32 val, struct i2c_msg *msg,
				  unsigned char *buf)
{
	msg->addr = client->addr;
	msg->flags = 0; /* Write */
	msg->len = 2 + len;
	msg->buf = buf;

	/* high byte goes out first */
	buf[0] = (u8) (reg >> 8);
	buf[1] = (u8) (reg & 0xff);

	switch (len) {
	case ET8EK8_REG_8BIT:
		buf[2] = (u8) (val) & 0xff;
		break;
	case ET8EK8_REG_16BIT:
		buf[2] = (u8) (val) & 0xff;
		buf[3] = (u8) (val >> 8) & 0xff;
		break;
	default:
		WARN_ONCE(1, ET8EK8_NAME ": %s: invalid message length.\n",
			  __func__);
	}
}

/*
 * A buffered write method that puts the wanted register write
 * commands in smaller number of message lists and passes the lists to
 * the i2c framework
 */
static int et8ek8_i2c_buffered_write_regs(struct i2c_client *client,
					  const struct et8ek8_reg *wnext,
					  int cnt)
{
	struct i2c_msg msg[ET8EK8_MAX_MSG];
	unsigned char data[ET8EK8_MAX_MSG][6];
	int wcnt = 0;
	u16 reg, data_length;
	u32 val;
	int rval;

	/* Create new write messages for all writes */
	while (wcnt < cnt) {
		data_length = wnext->type;
		reg = wnext->reg;
		val = wnext->val;
		wnext++;

		et8ek8_i2c_create_msg(client, data_length, reg,
				    val, &msg[wcnt], &data[wcnt][0]);

		/* Update write count */
		wcnt++;

		if (wcnt < ET8EK8_MAX_MSG)
			continue;

		rval = i2c_transfer(client->adapter, msg, wcnt);
		if (rval < 0)
			return rval;

		cnt -= wcnt;
		wcnt = 0;
	}

	rval = i2c_transfer(client->adapter, msg, wcnt);

	return rval < 0 ? rval : 0;
}

/*
 * Write a list of registers to i2c device.
 *
 * The list of registers is terminated by ET8EK8_REG_TERM.
 * Returns zero if successful, or non-zero otherwise.
 */
static int et8ek8_i2c_write_regs(struct i2c_client *client,
				 const struct et8ek8_reg *regs)
{
	int r, cnt = 0;
	const struct et8ek8_reg *next;

	if (!client->adapter)
		return -ENODEV;

	if (!regs)
		return -EINVAL;

	/* Initialize list pointers to the start of the list */
	next = regs;

	do {
		/*
		 * We have to go through the list to figure out how
		 * many regular writes we have in a row
		 */
		while (next->type != ET8EK8_REG_TERM &&
		       next->type != ET8EK8_REG_DELAY) {
			/*
			 * Here we check that the actual length fields
			 * are valid
			 */
			if (WARN(next->type != ET8EK8_REG_8BIT &&
				 next->type != ET8EK8_REG_16BIT,
				 "Invalid type = %d", next->type)) {
				return -EINVAL;
			}
			/*
			 * Increment count of successive writes and
			 * read pointer
			 */
			cnt++;
			next++;
		}

		/* Now we start writing ... */
		r = et8ek8_i2c_buffered_write_regs(client, regs, cnt);

		/* ... and then check that everything was OK */
		if (r < 0) {
			dev_err(&client->dev, "i2c transfer error!\n");
			return r;
		}

		/*
		 * If we ran into a sleep statement when going through
		 * the list, this is where we snooze for the required time
		 */
		if (next->type == ET8EK8_REG_DELAY) {
			msleep(next->val);
			/*
			 * ZZZ ...
			 * Update list pointers and cnt and start over ...
			 */
			next++;
			regs = next;
			cnt = 0;
		}
	} while (next->type != ET8EK8_REG_TERM);

	return 0;
}

/*
 * Write to a 8/16-bit register.
 * Returns zero if successful, or non-zero otherwise.
 */
static int et8ek8_i2c_write_reg(struct i2c_client *client, u16 data_length,
				u16 reg, u32 val)
{
	int r;
	struct i2c_msg msg;
	unsigned char data[6];

	if (!client->adapter)
		return -ENODEV;
	if (data_length != ET8EK8_REG_8BIT && data_length != ET8EK8_REG_16BIT)
		return -EINVAL;

	et8ek8_i2c_create_msg(client, data_length, reg, val, &msg, data);

	r = i2c_transfer(client->adapter, &msg, 1);
	if (r < 0) {
		dev_err(&client->dev,
			"wrote 0x%x to offset 0x%x error %d\n", val, reg, r);
		return r;
	}

	return 0;
}

static struct et8ek8_reglist *et8ek8_reglist_find_type(
		struct et8ek8_meta_reglist *meta,
		u16 type)
{
	struct et8ek8_reglist **next = &meta->reglist[0].ptr;

	while (*next) {
		if ((*next)->type == type)
			return *next;

		next++;
	}

	return NULL;
}

static int et8ek8_i2c_reglist_find_write(struct i2c_client *client,
					 struct et8ek8_meta_reglist *meta,
					 u16 type)
{
	struct et8ek8_reglist *reglist;

	reglist = et8ek8_reglist_find_type(meta, type);
	if (!reglist)
		return -EINVAL;

	return et8ek8_i2c_write_regs(client, reglist->regs);
}

static struct et8ek8_reglist **et8ek8_reglist_first(
		struct et8ek8_meta_reglist *meta)
{
	return &meta->reglist[0].ptr;
}

static void et8ek8_reglist_to_mbus(const struct et8ek8_reglist *reglist,
				   struct v4l2_mbus_framefmt *fmt)
{
	fmt->width = reglist->mode.window_width;
	fmt->height = reglist->mode.window_height;
	fmt->code = reglist->mode.bus_format;
}

static struct et8ek8_reglist *et8ek8_reglist_find_mode_fmt(
		struct et8ek8_meta_reglist *meta,
		struct v4l2_mbus_framefmt *fmt)
{
	struct et8ek8_reglist **list = et8ek8_reglist_first(meta);
	struct et8ek8_reglist *best_match = NULL;
	struct et8ek8_reglist *best_other = NULL;
	struct v4l2_mbus_framefmt format;
	unsigned int max_dist_match = (unsigned int)-1;
	unsigned int max_dist_other = (unsigned int)-1;

	/*
	 * Find the mode with the closest image size. The distance between
	 * image sizes is the size in pixels of the non-overlapping regions
	 * between the requested size and the frame-specified size.
	 *
	 * Store both the closest mode that matches the requested format, and
	 * the closest mode for all other formats. The best match is returned
	 * if found, otherwise the best mode with a non-matching format is
	 * returned.
	 */
	for (; *list; list++) {
		unsigned int dist;

		if ((*list)->type != ET8EK8_REGLIST_MODE)
			continue;

		et8ek8_reglist_to_mbus(*list, &format);

		dist = min(fmt->width, format.width)
		     * min(fmt->height, format.height);
		dist = format.width * format.height
		     + fmt->width * fmt->height - 2 * dist;


		if (fmt->code == format.code) {
			if (dist < max_dist_match || !best_match) {
				best_match = *list;
				max_dist_match = dist;
			}
		} else {
			if (dist < max_dist_other || !best_other) {
				best_other = *list;
				max_dist_other = dist;
			}
		}
	}

	return best_match ? best_match : best_other;
}

#define TIMEPERFRAME_AVG_FPS(t)						\
	(((t).denominator + ((t).numerator >> 1)) / (t).numerator)

static struct et8ek8_reglist *et8ek8_reglist_find_mode_ival(
		struct et8ek8_meta_reglist *meta,
		struct et8ek8_reglist *current_reglist,
		struct v4l2_fract *timeperframe)
{
	int fps = TIMEPERFRAME_AVG_FPS(*timeperframe);
	struct et8ek8_reglist **list = et8ek8_reglist_first(meta);
	struct et8ek8_mode *current_mode = &current_reglist->mode;

	for (; *list; list++) {
		struct et8ek8_mode *mode = &(*list)->mode;

		if ((*list)->type != ET8EK8_REGLIST_MODE)
			continue;

		if (mode->window_width != current_mode->window_width ||
		    mode->window_height != current_mode->window_height)
			continue;

		if (TIMEPERFRAME_AVG_FPS(mode->timeperframe) == fps)
			return *list;
	}

	return NULL;
}

static int et8ek8_reglist_cmp(const void *a, const void *b)
{
	const struct et8ek8_reglist **list1 = (const struct et8ek8_reglist **)a,
		**list2 = (const struct et8ek8_reglist **)b;

	/* Put real modes in the beginning. */
	if ((*list1)->type == ET8EK8_REGLIST_MODE &&
	    (*list2)->type != ET8EK8_REGLIST_MODE)
		return -1;
	if ((*list1)->type != ET8EK8_REGLIST_MODE &&
	    (*list2)->type == ET8EK8_REGLIST_MODE)
		return 1;

	/* Descending width. */
	if ((*list1)->mode.window_width > (*list2)->mode.window_width)
		return -1;
	if ((*list1)->mode.window_width < (*list2)->mode.window_width)
		return 1;

	if ((*list1)->mode.window_height > (*list2)->mode.window_height)
		return -1;
	if ((*list1)->mode.window_height < (*list2)->mode.window_height)
		return 1;

	return 0;
}

static int et8ek8_reglist_import(struct i2c_client *client,
				 struct et8ek8_meta_reglist *meta)
{
	int nlists = 0, i;

	dev_info(&client->dev, "meta_reglist version %s\n", meta->version);

	while (meta->reglist[nlists].ptr)
		nlists++;

	if (!nlists)
		return -EINVAL;

	sort(&meta->reglist[0].ptr, nlists, sizeof(meta->reglist[0].ptr),
	     et8ek8_reglist_cmp, NULL);

	i = nlists;
	nlists = 0;

	while (i--) {
		struct et8ek8_reglist *list;

		list = meta->reglist[nlists].ptr;

		dev_dbg(&client->dev,
		       "%s: type %d\tw %d\th %d\tfmt %x\tival %d/%d\tptr %p\n",
		       __func__,
		       list->type,
		       list->mode.window_width, list->mode.window_height,
		       list->mode.bus_format,
		       list->mode.timeperframe.numerator,
		       list->mode.timeperframe.denominator,
		       (void *)meta->reglist[nlists].ptr);

		nlists++;
	}

	return 0;
}

/* Called to change the V4L2 gain control value. This function
 * rounds and clamps the given value and updates the V4L2 control value.
 * If power is on, also updates the sensor analog and digital gains.
 * gain is in 0.1 EV (exposure value) units.
 */
static int et8ek8_set_gain(struct et8ek8_sensor *sensor, s32 gain)
{
	struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
	struct et8ek8_gain new;
	int r;

	new = et8ek8_gain_table[gain];

	/* FIXME: optimise I2C writes! */
	r = et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT,
				0x124a, new.analog >> 8);
	if (r)
		return r;
	r = et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT,
				0x1249, new.analog & 0xff);
	if (r)
		return r;

	r = et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT,
				0x124d, new.digital >> 8);
	if (r)
		return r;
	r = et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT,
				0x124c, new.digital & 0xff);

	return r;
}

static int et8ek8_set_test_pattern(struct et8ek8_sensor *sensor, s32 mode)
{
	struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);
	int cbh_mode, cbv_mode, tp_mode, din_sw, r1420, rval;

	/* Values for normal mode */
	cbh_mode = 0;
	cbv_mode = 0;
	tp_mode  = 0;
	din_sw   = 0x00;
	r1420    = 0xF0;

	if (mode) {
		/* Test pattern mode */
		if (mode < 5) {
			cbh_mode = 1;
			cbv_mode = 1;
			tp_mode  = mode + 3;
		} else {
			cbh_mode = 0;
			cbv_mode = 0;
			tp_mode  = mode - 4 + 3;
		}

		din_sw   = 0x01;
		r1420    = 0xE0;
	}

	rval = et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT, 0x111B,
				    tp_mode << 4);
	if (rval)
		return rval;

	rval = et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT, 0x1121,
				    cbh_mode << 7);
	if (rval)
		return rval;

	rval = et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT, 0x1124,
				    cbv_mode << 7);
	if (rval)
		return rval;

	rval = et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT, 0x112C, din_sw);
	if (rval)
		return rval;

	return et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT, 0x1420, r1420);
}

/* -----------------------------------------------------------------------------
 * V4L2 controls
 */

static int et8ek8_set_ctrl(struct v4l2_ctrl *ctrl)
{
	struct et8ek8_sensor *sensor =
		container_of(ctrl->handler, struct et8ek8_sensor, ctrl_handler);

	switch (ctrl->id) {
	case V4L2_CID_GAIN:
		return et8ek8_set_gain(sensor, ctrl->val);

	case V4L2_CID_EXPOSURE:
	{
		struct i2c_client *client =
			v4l2_get_subdevdata(&sensor->subdev);

		return et8ek8_i2c_write_reg(client, ET8EK8_REG_16BIT, 0x1243,
					    ctrl->val);
	}

	case V4L2_CID_TEST_PATTERN:
		return et8ek8_set_test_pattern(sensor, ctrl->val);

	case V4L2_CID_PIXEL_RATE:
		return 0;

	default:
		return -EINVAL;
	}
}

static const struct v4l2_ctrl_ops et8ek8_ctrl_ops = {
	.s_ctrl = et8ek8_set_ctrl,
};

static const char * const et8ek8_test_pattern_menu[] = {
	"Normal",
	"Vertical colorbar",
	"Horizontal colorbar",
	"Scale",
	"Ramp",
	"Small vertical colorbar",
	"Small horizontal colorbar",
	"Small scale",
	"Small ramp",
};

static int et8ek8_init_controls(struct et8ek8_sensor *sensor)
{
	s32 max_rows;

	v4l2_ctrl_handler_init(&sensor->ctrl_handler, 4);

	/* V4L2_CID_GAIN */
	v4l2_ctrl_new_std(&sensor->ctrl_handler, &et8ek8_ctrl_ops,
			  V4L2_CID_GAIN, 0, ARRAY_SIZE(et8ek8_gain_table) - 1,
			  1, 0);

	max_rows = sensor->current_reglist->mode.max_exp;
	{
		u32 min = 1, max = max_rows;

		sensor->exposure =
			v4l2_ctrl_new_std(&sensor->ctrl_handler,
					  &et8ek8_ctrl_ops, V4L2_CID_EXPOSURE,
					  min, max, min, max);
	}

	/* V4L2_CID_PIXEL_RATE */
	sensor->pixel_rate =
		v4l2_ctrl_new_std(&sensor->ctrl_handler, &et8ek8_ctrl_ops,
		V4L2_CID_PIXEL_RATE, 1, INT_MAX, 1, 1);

	/* V4L2_CID_TEST_PATTERN */
	v4l2_ctrl_new_std_menu_items(&sensor->ctrl_handler,
				     &et8ek8_ctrl_ops, V4L2_CID_TEST_PATTERN,
				     ARRAY_SIZE(et8ek8_test_pattern_menu) - 1,
				     0, 0, et8ek8_test_pattern_menu);

	if (sensor->ctrl_handler.error)
		return sensor->ctrl_handler.error;

	sensor->subdev.ctrl_handler = &sensor->ctrl_handler;

	return 0;
}

static void et8ek8_update_controls(struct et8ek8_sensor *sensor)
{
	struct v4l2_ctrl *ctrl;
	struct et8ek8_mode *mode = &sensor->current_reglist->mode;

	u32 min, max, pixel_rate;
	static const int S = 8;

	ctrl = sensor->exposure;

	min = 1;
	max = mode->max_exp;

	/*
	 * Calculate average pixel clock per line. Assume buffers can spread
	 * the data over horizontal blanking time. Rounding upwards.
	 * Formula taken from stock Nokia N900 kernel.
	 */
	pixel_rate = ((mode->pixel_clock + (1 << S) - 1) >> S) + mode->width;
	pixel_rate = mode->window_width * (pixel_rate - 1) / mode->width;

	__v4l2_ctrl_modify_range(ctrl, min, max, min, max);
	__v4l2_ctrl_s_ctrl_int64(sensor->pixel_rate, pixel_rate << S);
}

static int et8ek8_configure(struct et8ek8_sensor *sensor)
{
	struct v4l2_subdev *subdev = &sensor->subdev;
	struct i2c_client *client = v4l2_get_subdevdata(subdev);
	int rval;

	rval = et8ek8_i2c_write_regs(client, sensor->current_reglist->regs);
	if (rval)
		goto fail;

	/* Controls set while the power to the sensor is turned off are saved
	 * but not applied to the hardware. Now that we're about to start
	 * streaming apply all the current values to the hardware.
	 */
	rval = v4l2_ctrl_handler_setup(&sensor->ctrl_handler);
	if (rval)
		goto fail;

	return 0;

fail:
	dev_err(&client->dev, "sensor configuration failed\n");

	return rval;
}

static int et8ek8_stream_on(struct et8ek8_sensor *sensor)
{
	struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);

	return et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT, 0x1252, 0xb0);
}

static int et8ek8_stream_off(struct et8ek8_sensor *sensor)
{
	struct i2c_client *client = v4l2_get_subdevdata(&sensor->subdev);

	return et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT, 0x1252, 0x30);
}

static int et8ek8_s_stream(struct v4l2_subdev *subdev, int streaming)
{
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);
	int ret;

	if (!streaming)
		return et8ek8_stream_off(sensor);

	ret = et8ek8_configure(sensor);
	if (ret < 0)
		return ret;

	return et8ek8_stream_on(sensor);
}

/* --------------------------------------------------------------------------
 * V4L2 subdev operations
 */

static int et8ek8_power_off(struct et8ek8_sensor *sensor)
{
	gpiod_set_value(sensor->reset, 0);
	udelay(1);

	clk_disable_unprepare(sensor->ext_clk);

	return regulator_disable(sensor->vana);
}

static int et8ek8_power_on(struct et8ek8_sensor *sensor)
{
	struct v4l2_subdev *subdev = &sensor->subdev;
	struct i2c_client *client = v4l2_get_subdevdata(subdev);
	unsigned int xclk_freq;
	int val, rval;

	rval = regulator_enable(sensor->vana);
	if (rval) {
		dev_err(&client->dev, "failed to enable vana regulator\n");
		return rval;
	}

	if (sensor->current_reglist)
		xclk_freq = sensor->current_reglist->mode.ext_clock;
	else
		xclk_freq = sensor->xclk_freq;

	rval = clk_set_rate(sensor->ext_clk, xclk_freq);
	if (rval < 0) {
		dev_err(&client->dev, "unable to set extclk clock freq to %u\n",
			xclk_freq);
		goto out;
	}
	rval = clk_prepare_enable(sensor->ext_clk);
	if (rval < 0) {
		dev_err(&client->dev, "failed to enable extclk\n");
		goto out;
	}

	if (rval)
		goto out;

	udelay(10); /* I wish this is a good value */

	gpiod_set_value(sensor->reset, 1);

	msleep(5000 * 1000 / xclk_freq + 1); /* Wait 5000 cycles */

	rval = et8ek8_i2c_reglist_find_write(client, &meta_reglist,
					     ET8EK8_REGLIST_POWERON);
	if (rval)
		goto out;

#ifdef USE_CRC
	rval = et8ek8_i2c_read_reg(client, ET8EK8_REG_8BIT, 0x1263, &val);
	if (rval)
		goto out;
#if USE_CRC /* TODO get crc setting from DT */
	val |= BIT(4);
#else
	val &= ~BIT(4);
#endif
	rval = et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT, 0x1263, val);
	if (rval)
		goto out;
#endif

out:
	if (rval)
		et8ek8_power_off(sensor);

	return rval;
}

/* --------------------------------------------------------------------------
 * V4L2 subdev video operations
 */
#define MAX_FMTS 4
static int et8ek8_enum_mbus_code(struct v4l2_subdev *subdev,
				 struct v4l2_subdev_state *sd_state,
				 struct v4l2_subdev_mbus_code_enum *code)
{
	struct et8ek8_reglist **list =
			et8ek8_reglist_first(&meta_reglist);
	u32 pixelformat[MAX_FMTS];
	int npixelformat = 0;

	if (code->index >= MAX_FMTS)
		return -EINVAL;

	for (; *list; list++) {
		struct et8ek8_mode *mode = &(*list)->mode;
		int i;

		if ((*list)->type != ET8EK8_REGLIST_MODE)
			continue;

		for (i = 0; i < npixelformat; i++) {
			if (pixelformat[i] == mode->bus_format)
				break;
		}
		if (i != npixelformat)
			continue;

		if (code->index == npixelformat) {
			code->code = mode->bus_format;
			return 0;
		}

		pixelformat[npixelformat] = mode->bus_format;
		npixelformat++;
	}

	return -EINVAL;
}

static int et8ek8_enum_frame_size(struct v4l2_subdev *subdev,
				  struct v4l2_subdev_state *sd_state,
				  struct v4l2_subdev_frame_size_enum *fse)
{
	struct et8ek8_reglist **list =
			et8ek8_reglist_first(&meta_reglist);
	struct v4l2_mbus_framefmt format;
	int cmp_width = INT_MAX;
	int cmp_height = INT_MAX;
	int index = fse->index;

	for (; *list; list++) {
		if ((*list)->type != ET8EK8_REGLIST_MODE)
			continue;

		et8ek8_reglist_to_mbus(*list, &format);
		if (fse->code != format.code)
			continue;

		/* Assume that the modes are grouped by frame size. */
		if (format.width == cmp_width && format.height == cmp_height)
			continue;

		cmp_width = format.width;
		cmp_height = format.height;

		if (index-- == 0) {
			fse->min_width = format.width;
			fse->min_height = format.height;
			fse->max_width = format.width;
			fse->max_height = format.height;
			return 0;
		}
	}

	return -EINVAL;
}

static int et8ek8_enum_frame_ival(struct v4l2_subdev *subdev,
				  struct v4l2_subdev_state *sd_state,
				  struct v4l2_subdev_frame_interval_enum *fie)
{
	struct et8ek8_reglist **list =
			et8ek8_reglist_first(&meta_reglist);
	struct v4l2_mbus_framefmt format;
	int index = fie->index;

	for (; *list; list++) {
		struct et8ek8_mode *mode = &(*list)->mode;

		if ((*list)->type != ET8EK8_REGLIST_MODE)
			continue;

		et8ek8_reglist_to_mbus(*list, &format);
		if (fie->code != format.code)
			continue;

		if (fie->width != format.width || fie->height != format.height)
			continue;

		if (index-- == 0) {
			fie->interval = mode->timeperframe;
			return 0;
		}
	}

	return -EINVAL;
}

static struct v4l2_mbus_framefmt *
__et8ek8_get_pad_format(struct et8ek8_sensor *sensor,
			struct v4l2_subdev_state *sd_state,
			unsigned int pad, enum v4l2_subdev_format_whence which)
{
	switch (which) {
	case V4L2_SUBDEV_FORMAT_TRY:
		return v4l2_subdev_get_try_format(&sensor->subdev, sd_state,
						  pad);
	case V4L2_SUBDEV_FORMAT_ACTIVE:
		return &sensor->format;
	default:
		return NULL;
	}
}

static int et8ek8_get_pad_format(struct v4l2_subdev *subdev,
				 struct v4l2_subdev_state *sd_state,
				 struct v4l2_subdev_format *fmt)
{
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);
	struct v4l2_mbus_framefmt *format;

	format = __et8ek8_get_pad_format(sensor, sd_state, fmt->pad,
					 fmt->which);
	if (!format)
		return -EINVAL;

	fmt->format = *format;

	return 0;
}

static int et8ek8_set_pad_format(struct v4l2_subdev *subdev,
				 struct v4l2_subdev_state *sd_state,
				 struct v4l2_subdev_format *fmt)
{
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);
	struct v4l2_mbus_framefmt *format;
	struct et8ek8_reglist *reglist;

	format = __et8ek8_get_pad_format(sensor, sd_state, fmt->pad,
					 fmt->which);
	if (!format)
		return -EINVAL;

	reglist = et8ek8_reglist_find_mode_fmt(&meta_reglist, &fmt->format);
	et8ek8_reglist_to_mbus(reglist, &fmt->format);
	*format = fmt->format;

	if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
		sensor->current_reglist = reglist;
		et8ek8_update_controls(sensor);
	}

	return 0;
}

static int et8ek8_get_frame_interval(struct v4l2_subdev *subdev,
				     struct v4l2_subdev_frame_interval *fi)
{
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);

	memset(fi, 0, sizeof(*fi));
	fi->interval = sensor->current_reglist->mode.timeperframe;

	return 0;
}

static int et8ek8_set_frame_interval(struct v4l2_subdev *subdev,
				     struct v4l2_subdev_frame_interval *fi)
{
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);
	struct et8ek8_reglist *reglist;

	reglist = et8ek8_reglist_find_mode_ival(&meta_reglist,
						sensor->current_reglist,
						&fi->interval);

	if (!reglist)
		return -EINVAL;

	if (sensor->current_reglist->mode.ext_clock != reglist->mode.ext_clock)
		return -EINVAL;

	sensor->current_reglist = reglist;
	et8ek8_update_controls(sensor);

	return 0;
}

static int et8ek8_g_priv_mem(struct v4l2_subdev *subdev)
{
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);
	struct i2c_client *client = v4l2_get_subdevdata(subdev);
	unsigned int length = ET8EK8_PRIV_MEM_SIZE;
	unsigned int offset = 0;
	u8 *ptr  = sensor->priv_mem;
	int rval = 0;

	/* Read the EEPROM window-by-window, each window 8 bytes */
	do {
		u8 buffer[PRIV_MEM_WIN_SIZE];
		struct i2c_msg msg;
		int bytes, i;
		int ofs;

		/* Set the current window */
		rval = et8ek8_i2c_write_reg(client, ET8EK8_REG_8BIT, 0x0001,
					    0xe0 | (offset >> 3));
		if (rval < 0)
			return rval;

		/* Wait for status bit */
		for (i = 0; i < 1000; ++i) {
			u32 status;

			rval = et8ek8_i2c_read_reg(client, ET8EK8_REG_8BIT,
						   0x0003, &status);
			if (rval < 0)
				return rval;
			if (!(status & 0x08))
				break;
			usleep_range(1000, 2000);
		}

		if (i == 1000)
			return -EIO;

		/* Read window, 8 bytes at once, and copy to user space */
		ofs = offset & 0x07;	/* Offset within this window */
		bytes = length + ofs > 8 ? 8-ofs : length;
		msg.addr = client->addr;
		msg.flags = 0;
		msg.len = 2;
		msg.buf = buffer;
		ofs += PRIV_MEM_START_REG;
		buffer[0] = (u8)(ofs >> 8);
		buffer[1] = (u8)(ofs & 0xFF);

		rval = i2c_transfer(client->adapter, &msg, 1);
		if (rval < 0)
			return rval;

		mdelay(ET8EK8_I2C_DELAY);
		msg.addr = client->addr;
		msg.len = bytes;
		msg.flags = I2C_M_RD;
		msg.buf = buffer;
		memset(buffer, 0, sizeof(buffer));

		rval = i2c_transfer(client->adapter, &msg, 1);
		if (rval < 0)
			return rval;

		rval = 0;
		memcpy(ptr, buffer, bytes);

		length -= bytes;
		offset += bytes;
		ptr += bytes;
	} while (length > 0);

	return rval;
}

static int et8ek8_dev_init(struct v4l2_subdev *subdev)
{
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);
	struct i2c_client *client = v4l2_get_subdevdata(subdev);
	int rval, rev_l, rev_h;

	rval = et8ek8_power_on(sensor);
	if (rval) {
		dev_err(&client->dev, "could not power on\n");
		return rval;
	}

	rval = et8ek8_i2c_read_reg(client, ET8EK8_REG_8BIT,
				   REG_REVISION_NUMBER_L, &rev_l);
	if (!rval)
		rval = et8ek8_i2c_read_reg(client, ET8EK8_REG_8BIT,
					   REG_REVISION_NUMBER_H, &rev_h);
	if (rval) {
		dev_err(&client->dev, "no et8ek8 sensor detected\n");
		goto out_poweroff;
	}

	sensor->version = (rev_h << 8) + rev_l;
	if (sensor->version != ET8EK8_REV_1 && sensor->version != ET8EK8_REV_2)
		dev_info(&client->dev,
			 "unknown version 0x%x detected, continuing anyway\n",
			 sensor->version);

	rval = et8ek8_reglist_import(client, &meta_reglist);
	if (rval) {
		dev_err(&client->dev,
			"invalid register list %s, import failed\n",
			ET8EK8_NAME);
		goto out_poweroff;
	}

	sensor->current_reglist = et8ek8_reglist_find_type(&meta_reglist,
							   ET8EK8_REGLIST_MODE);
	if (!sensor->current_reglist) {
		dev_err(&client->dev,
			"invalid register list %s, no mode found\n",
			ET8EK8_NAME);
		rval = -ENODEV;
		goto out_poweroff;
	}

	et8ek8_reglist_to_mbus(sensor->current_reglist, &sensor->format);

	rval = et8ek8_i2c_reglist_find_write(client, &meta_reglist,
					     ET8EK8_REGLIST_POWERON);
	if (rval) {
		dev_err(&client->dev,
			"invalid register list %s, no POWERON mode found\n",
			ET8EK8_NAME);
		goto out_poweroff;
	}
	rval = et8ek8_stream_on(sensor); /* Needed to be able to read EEPROM */
	if (rval)
		goto out_poweroff;
	rval = et8ek8_g_priv_mem(subdev);
	if (rval)
		dev_warn(&client->dev,
			"can not read OTP (EEPROM) memory from sensor\n");
	rval = et8ek8_stream_off(sensor);
	if (rval)
		goto out_poweroff;

	rval = et8ek8_power_off(sensor);
	if (rval)
		goto out_poweroff;

	return 0;

out_poweroff:
	et8ek8_power_off(sensor);

	return rval;
}

/* --------------------------------------------------------------------------
 * sysfs attributes
 */
static ssize_t
priv_mem_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct v4l2_subdev *subdev = dev_get_drvdata(dev);
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);

#if PAGE_SIZE < ET8EK8_PRIV_MEM_SIZE
#error PAGE_SIZE too small!
#endif

	memcpy(buf, sensor->priv_mem, ET8EK8_PRIV_MEM_SIZE);

	return ET8EK8_PRIV_MEM_SIZE;
}
static DEVICE_ATTR_RO(priv_mem);

/* --------------------------------------------------------------------------
 * V4L2 subdev core operations
 */

static int
et8ek8_registered(struct v4l2_subdev *subdev)
{
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);
	struct i2c_client *client = v4l2_get_subdevdata(subdev);
	int rval;

	dev_dbg(&client->dev, "registered!");

	rval = device_create_file(&client->dev, &dev_attr_priv_mem);
	if (rval) {
		dev_err(&client->dev, "could not register sysfs entry\n");
		return rval;
	}

	rval = et8ek8_dev_init(subdev);
	if (rval)
		goto err_file;

	rval = et8ek8_init_controls(sensor);
	if (rval) {
		dev_err(&client->dev, "controls initialization failed\n");
		goto err_file;
	}

	__et8ek8_get_pad_format(sensor, NULL, 0, V4L2_SUBDEV_FORMAT_ACTIVE);

	return 0;

err_file:
	device_remove_file(&client->dev, &dev_attr_priv_mem);

	return rval;
}

static int __et8ek8_set_power(struct et8ek8_sensor *sensor, bool on)
{
	return on ? et8ek8_power_on(sensor) : et8ek8_power_off(sensor);
}

static int et8ek8_set_power(struct v4l2_subdev *subdev, int on)
{
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);
	int ret = 0;

	mutex_lock(&sensor->power_lock);

	/* If the power count is modified from 0 to != 0 or from != 0 to 0,
	 * update the power state.
	 */
	if (sensor->power_count == !on) {
		ret = __et8ek8_set_power(sensor, !!on);
		if (ret < 0)
			goto done;
	}

	/* Update the power count. */
	sensor->power_count += on ? 1 : -1;
	WARN_ON(sensor->power_count < 0);

done:
	mutex_unlock(&sensor->power_lock);

	return ret;
}

static int et8ek8_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(sd);
	struct v4l2_mbus_framefmt *format;
	struct et8ek8_reglist *reglist;

	reglist = et8ek8_reglist_find_type(&meta_reglist, ET8EK8_REGLIST_MODE);
	format = __et8ek8_get_pad_format(sensor, fh->state, 0,
					 V4L2_SUBDEV_FORMAT_TRY);
	et8ek8_reglist_to_mbus(reglist, format);

	return et8ek8_set_power(sd, true);
}

static int et8ek8_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
	return et8ek8_set_power(sd, false);
}

static const struct v4l2_subdev_video_ops et8ek8_video_ops = {
	.s_stream = et8ek8_s_stream,
	.g_frame_interval = et8ek8_get_frame_interval,
	.s_frame_interval = et8ek8_set_frame_interval,
};

static const struct v4l2_subdev_core_ops et8ek8_core_ops = {
	.s_power = et8ek8_set_power,
};

static const struct v4l2_subdev_pad_ops et8ek8_pad_ops = {
	.enum_mbus_code = et8ek8_enum_mbus_code,
	.enum_frame_size = et8ek8_enum_frame_size,
	.enum_frame_interval = et8ek8_enum_frame_ival,
	.get_fmt = et8ek8_get_pad_format,
	.set_fmt = et8ek8_set_pad_format,
};

static const struct v4l2_subdev_ops et8ek8_ops = {
	.core = &et8ek8_core_ops,
	.video = &et8ek8_video_ops,
	.pad = &et8ek8_pad_ops,
};

static const struct v4l2_subdev_internal_ops et8ek8_internal_ops = {
	.registered = et8ek8_registered,
	.open = et8ek8_open,
	.close = et8ek8_close,
};

/* --------------------------------------------------------------------------
 * I2C driver
 */
static int __maybe_unused et8ek8_suspend(struct device *dev)
{
	struct v4l2_subdev *subdev = dev_get_drvdata(dev);
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);

	if (!sensor->power_count)
		return 0;

	return __et8ek8_set_power(sensor, false);
}

static int __maybe_unused et8ek8_resume(struct device *dev)
{
	struct v4l2_subdev *subdev = dev_get_drvdata(dev);
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);

	if (!sensor->power_count)
		return 0;

	return __et8ek8_set_power(sensor, true);
}

static int et8ek8_probe(struct i2c_client *client)
{
	struct et8ek8_sensor *sensor;
	struct device *dev = &client->dev;
	int ret;

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

	sensor->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
	if (IS_ERR(sensor->reset)) {
		dev_dbg(&client->dev, "could not request reset gpio\n");
		return PTR_ERR(sensor->reset);
	}

	sensor->vana = devm_regulator_get(dev, "vana");
	if (IS_ERR(sensor->vana)) {
		dev_err(&client->dev, "could not get regulator for vana\n");
		return PTR_ERR(sensor->vana);
	}

	sensor->ext_clk = devm_clk_get(dev, NULL);
	if (IS_ERR(sensor->ext_clk)) {
		dev_err(&client->dev, "could not get clock\n");
		return PTR_ERR(sensor->ext_clk);
	}

	ret = of_property_read_u32(dev->of_node, "clock-frequency",
				   &sensor->xclk_freq);
	if (ret) {
		dev_warn(dev, "can't get clock-frequency\n");
		return ret;
	}

	mutex_init(&sensor->power_lock);

	v4l2_i2c_subdev_init(&sensor->subdev, client, &et8ek8_ops);
	sensor->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
	sensor->subdev.internal_ops = &et8ek8_internal_ops;

	sensor->subdev.entity.function = MEDIA_ENT_F_CAM_SENSOR;
	sensor->pad.flags = MEDIA_PAD_FL_SOURCE;
	ret = media_entity_pads_init(&sensor->subdev.entity, 1, &sensor->pad);
	if (ret < 0) {
		dev_err(&client->dev, "media entity init failed!\n");
		goto err_mutex;
	}

	ret = v4l2_async_register_subdev_sensor(&sensor->subdev);
	if (ret < 0)
		goto err_entity;

	dev_dbg(dev, "initialized!\n");

	return 0;

err_entity:
	media_entity_cleanup(&sensor->subdev.entity);
err_mutex:
	mutex_destroy(&sensor->power_lock);
	return ret;
}

static void __exit et8ek8_remove(struct i2c_client *client)
{
	struct v4l2_subdev *subdev = i2c_get_clientdata(client);
	struct et8ek8_sensor *sensor = to_et8ek8_sensor(subdev);

	if (sensor->power_count) {
		WARN_ON(1);
		et8ek8_power_off(sensor);
		sensor->power_count = 0;
	}

	v4l2_device_unregister_subdev(&sensor->subdev);
	device_remove_file(&client->dev, &dev_attr_priv_mem);
	v4l2_ctrl_handler_free(&sensor->ctrl_handler);
	v4l2_async_unregister_subdev(&sensor->subdev);
	media_entity_cleanup(&sensor->subdev.entity);
	mutex_destroy(&sensor->power_lock);
}

static const struct of_device_id et8ek8_of_table[] = {
	{ .compatible = "toshiba,et8ek8" },
	{ },
};
MODULE_DEVICE_TABLE(of, et8ek8_of_table);

static const struct i2c_device_id et8ek8_id_table[] = {
	{ ET8EK8_NAME, 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, et8ek8_id_table);

static const struct dev_pm_ops et8ek8_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(et8ek8_suspend, et8ek8_resume)
};

static struct i2c_driver et8ek8_i2c_driver = {
	.driver		= {
		.name	= ET8EK8_NAME,
		.pm	= &et8ek8_pm_ops,
		.of_match_table	= et8ek8_of_table,
	},
	.probe_new	= et8ek8_probe,
	.remove		= __exit_p(et8ek8_remove),
	.id_table	= et8ek8_id_table,
};

module_i2c_driver(et8ek8_i2c_driver);

MODULE_AUTHOR("Sakari Ailus <sakari.ailus@iki.fi>, Pavel Machek <pavel@ucw.cz");
MODULE_DESCRIPTION("Toshiba ET8EK8 camera sensor driver");
MODULE_LICENSE("GPL");