summaryrefslogtreecommitdiffstats
path: root/drivers/media/i2c/mt9m001.c
blob: 12d3e86bdc0fdcda70008905569ab0ffaa8347b5 (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
// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for MT9M001 CMOS Image Sensor from Micron
 *
 * Copyright (C) 2008, Guennadi Liakhovetski <kernel@pengutronix.de>
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/log2.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/videodev2.h>

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

/*
 * mt9m001 i2c address 0x5d
 */

/* mt9m001 selected register addresses */
#define MT9M001_CHIP_VERSION		0x00
#define MT9M001_ROW_START		0x01
#define MT9M001_COLUMN_START		0x02
#define MT9M001_WINDOW_HEIGHT		0x03
#define MT9M001_WINDOW_WIDTH		0x04
#define MT9M001_HORIZONTAL_BLANKING	0x05
#define MT9M001_VERTICAL_BLANKING	0x06
#define MT9M001_OUTPUT_CONTROL		0x07
#define MT9M001_SHUTTER_WIDTH		0x09
#define MT9M001_FRAME_RESTART		0x0b
#define MT9M001_SHUTTER_DELAY		0x0c
#define MT9M001_RESET			0x0d
#define MT9M001_READ_OPTIONS1		0x1e
#define MT9M001_READ_OPTIONS2		0x20
#define MT9M001_GLOBAL_GAIN		0x35
#define MT9M001_CHIP_ENABLE		0xF1

#define MT9M001_MAX_WIDTH		1280
#define MT9M001_MAX_HEIGHT		1024
#define MT9M001_MIN_WIDTH		48
#define MT9M001_MIN_HEIGHT		32
#define MT9M001_COLUMN_SKIP		20
#define MT9M001_ROW_SKIP		12
#define MT9M001_DEFAULT_HBLANK		9
#define MT9M001_DEFAULT_VBLANK		25

/* MT9M001 has only one fixed colorspace per pixelcode */
struct mt9m001_datafmt {
	u32	code;
	enum v4l2_colorspace		colorspace;
};

/* Find a data format by a pixel code in an array */
static const struct mt9m001_datafmt *mt9m001_find_datafmt(
	u32 code, const struct mt9m001_datafmt *fmt,
	int n)
{
	int i;
	for (i = 0; i < n; i++)
		if (fmt[i].code == code)
			return fmt + i;

	return NULL;
}

static const struct mt9m001_datafmt mt9m001_colour_fmts[] = {
	/*
	 * Order important: first natively supported,
	 * second supported with a GPIO extender
	 */
	{MEDIA_BUS_FMT_SBGGR10_1X10, V4L2_COLORSPACE_SRGB},
	{MEDIA_BUS_FMT_SBGGR8_1X8, V4L2_COLORSPACE_SRGB},
};

static const struct mt9m001_datafmt mt9m001_monochrome_fmts[] = {
	/* Order important - see above */
	{MEDIA_BUS_FMT_Y10_1X10, V4L2_COLORSPACE_JPEG},
	{MEDIA_BUS_FMT_Y8_1X8, V4L2_COLORSPACE_JPEG},
};

struct mt9m001 {
	struct v4l2_subdev subdev;
	struct v4l2_ctrl_handler hdl;
	struct {
		/* exposure/auto-exposure cluster */
		struct v4l2_ctrl *autoexposure;
		struct v4l2_ctrl *exposure;
	};
	struct mutex mutex;
	struct v4l2_rect rect;	/* Sensor window */
	struct clk *clk;
	struct gpio_desc *standby_gpio;
	struct gpio_desc *reset_gpio;
	const struct mt9m001_datafmt *fmt;
	const struct mt9m001_datafmt *fmts;
	int num_fmts;
	unsigned int total_h;
	unsigned short y_skip_top;	/* Lines to skip at the top */
	struct media_pad pad;
};

static struct mt9m001 *to_mt9m001(const struct i2c_client *client)
{
	return container_of(i2c_get_clientdata(client), struct mt9m001, subdev);
}

static int reg_read(struct i2c_client *client, const u8 reg)
{
	return i2c_smbus_read_word_swapped(client, reg);
}

static int reg_write(struct i2c_client *client, const u8 reg,
		     const u16 data)
{
	return i2c_smbus_write_word_swapped(client, reg, data);
}

static int reg_set(struct i2c_client *client, const u8 reg,
		   const u16 data)
{
	int ret;

	ret = reg_read(client, reg);
	if (ret < 0)
		return ret;
	return reg_write(client, reg, ret | data);
}

static int reg_clear(struct i2c_client *client, const u8 reg,
		     const u16 data)
{
	int ret;

	ret = reg_read(client, reg);
	if (ret < 0)
		return ret;
	return reg_write(client, reg, ret & ~data);
}

struct mt9m001_reg {
	u8 reg;
	u16 data;
};

static int multi_reg_write(struct i2c_client *client,
			   const struct mt9m001_reg *regs, int num)
{
	int i;

	for (i = 0; i < num; i++) {
		int ret = reg_write(client, regs[i].reg, regs[i].data);

		if (ret)
			return ret;
	}

	return 0;
}

static int mt9m001_init(struct i2c_client *client)
{
	static const struct mt9m001_reg init_regs[] = {
		/*
		 * Issue a soft reset. This returns all registers to their
		 * default values.
		 */
		{ MT9M001_RESET, 1 },
		{ MT9M001_RESET, 0 },
		/* Disable chip, synchronous option update */
		{ MT9M001_OUTPUT_CONTROL, 0 }
	};

	dev_dbg(&client->dev, "%s\n", __func__);

	return multi_reg_write(client, init_regs, ARRAY_SIZE(init_regs));
}

static int mt9m001_apply_selection(struct v4l2_subdev *sd)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct mt9m001 *mt9m001 = to_mt9m001(client);
	const struct mt9m001_reg regs[] = {
		/* Blanking and start values - default... */
		{ MT9M001_HORIZONTAL_BLANKING, MT9M001_DEFAULT_HBLANK },
		{ MT9M001_VERTICAL_BLANKING, MT9M001_DEFAULT_VBLANK },
		/*
		 * The caller provides a supported format, as verified per
		 * call to .set_fmt(FORMAT_TRY).
		 */
		{ MT9M001_COLUMN_START, mt9m001->rect.left },
		{ MT9M001_ROW_START, mt9m001->rect.top },
		{ MT9M001_WINDOW_WIDTH, mt9m001->rect.width - 1 },
		{ MT9M001_WINDOW_HEIGHT,
			mt9m001->rect.height + mt9m001->y_skip_top - 1 },
	};

	return multi_reg_write(client, regs, ARRAY_SIZE(regs));
}

static int mt9m001_s_stream(struct v4l2_subdev *sd, int enable)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct mt9m001 *mt9m001 = to_mt9m001(client);
	int ret = 0;

	mutex_lock(&mt9m001->mutex);

	if (enable) {
		ret = pm_runtime_resume_and_get(&client->dev);
		if (ret < 0)
			goto unlock;

		ret = mt9m001_apply_selection(sd);
		if (ret)
			goto put_unlock;

		ret = __v4l2_ctrl_handler_setup(&mt9m001->hdl);
		if (ret)
			goto put_unlock;

		/* Switch to master "normal" mode */
		ret = reg_write(client, MT9M001_OUTPUT_CONTROL, 2);
		if (ret < 0)
			goto put_unlock;
	} else {
		/* Switch to master stop sensor readout */
		reg_write(client, MT9M001_OUTPUT_CONTROL, 0);
		pm_runtime_put(&client->dev);
	}

	mutex_unlock(&mt9m001->mutex);

	return 0;

put_unlock:
	pm_runtime_put(&client->dev);
unlock:
	mutex_unlock(&mt9m001->mutex);

	return ret;
}

static int mt9m001_set_selection(struct v4l2_subdev *sd,
		struct v4l2_subdev_state *sd_state,
		struct v4l2_subdev_selection *sel)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct mt9m001 *mt9m001 = to_mt9m001(client);
	struct v4l2_rect rect = sel->r;

	if (sel->which != V4L2_SUBDEV_FORMAT_ACTIVE ||
	    sel->target != V4L2_SEL_TGT_CROP)
		return -EINVAL;

	if (mt9m001->fmts == mt9m001_colour_fmts)
		/*
		 * Bayer format - even number of rows for simplicity,
		 * but let the user play with the top row.
		 */
		rect.height = ALIGN(rect.height, 2);

	/* Datasheet requirement: see register description */
	rect.width = ALIGN(rect.width, 2);
	rect.left = ALIGN(rect.left, 2);

	rect.width = clamp_t(u32, rect.width, MT9M001_MIN_WIDTH,
			MT9M001_MAX_WIDTH);
	rect.left = clamp_t(u32, rect.left, MT9M001_COLUMN_SKIP,
			MT9M001_COLUMN_SKIP + MT9M001_MAX_WIDTH - rect.width);

	rect.height = clamp_t(u32, rect.height, MT9M001_MIN_HEIGHT,
			MT9M001_MAX_HEIGHT);
	rect.top = clamp_t(u32, rect.top, MT9M001_ROW_SKIP,
			MT9M001_ROW_SKIP + MT9M001_MAX_HEIGHT - rect.height);

	mt9m001->total_h = rect.height + mt9m001->y_skip_top +
			   MT9M001_DEFAULT_VBLANK;

	mt9m001->rect = rect;

	return 0;
}

static int mt9m001_get_selection(struct v4l2_subdev *sd,
		struct v4l2_subdev_state *sd_state,
		struct v4l2_subdev_selection *sel)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct mt9m001 *mt9m001 = to_mt9m001(client);

	if (sel->which != V4L2_SUBDEV_FORMAT_ACTIVE)
		return -EINVAL;

	switch (sel->target) {
	case V4L2_SEL_TGT_CROP_BOUNDS:
		sel->r.left = MT9M001_COLUMN_SKIP;
		sel->r.top = MT9M001_ROW_SKIP;
		sel->r.width = MT9M001_MAX_WIDTH;
		sel->r.height = MT9M001_MAX_HEIGHT;
		return 0;
	case V4L2_SEL_TGT_CROP:
		sel->r = mt9m001->rect;
		return 0;
	default:
		return -EINVAL;
	}
}

static int mt9m001_get_fmt(struct v4l2_subdev *sd,
		struct v4l2_subdev_state *sd_state,
		struct v4l2_subdev_format *format)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct mt9m001 *mt9m001 = to_mt9m001(client);
	struct v4l2_mbus_framefmt *mf = &format->format;

	if (format->pad)
		return -EINVAL;

	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
		mf = v4l2_subdev_state_get_format(sd_state, 0);
		format->format = *mf;
		return 0;
	}

	mf->width	= mt9m001->rect.width;
	mf->height	= mt9m001->rect.height;
	mf->code	= mt9m001->fmt->code;
	mf->colorspace	= mt9m001->fmt->colorspace;
	mf->field	= V4L2_FIELD_NONE;
	mf->ycbcr_enc	= V4L2_YCBCR_ENC_DEFAULT;
	mf->quantization = V4L2_QUANTIZATION_DEFAULT;
	mf->xfer_func	= V4L2_XFER_FUNC_DEFAULT;

	return 0;
}

static int mt9m001_s_fmt(struct v4l2_subdev *sd,
			 const struct mt9m001_datafmt *fmt,
			 struct v4l2_mbus_framefmt *mf)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct mt9m001 *mt9m001 = to_mt9m001(client);
	struct v4l2_subdev_selection sel = {
		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
		.target = V4L2_SEL_TGT_CROP,
		.r.left = mt9m001->rect.left,
		.r.top = mt9m001->rect.top,
		.r.width = mf->width,
		.r.height = mf->height,
	};
	int ret;

	/* No support for scaling so far, just crop. TODO: use skipping */
	ret = mt9m001_set_selection(sd, NULL, &sel);
	if (!ret) {
		mf->width	= mt9m001->rect.width;
		mf->height	= mt9m001->rect.height;
		mt9m001->fmt	= fmt;
		mf->colorspace	= fmt->colorspace;
	}

	return ret;
}

static int mt9m001_set_fmt(struct v4l2_subdev *sd,
		struct v4l2_subdev_state *sd_state,
		struct v4l2_subdev_format *format)
{
	struct v4l2_mbus_framefmt *mf = &format->format;
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct mt9m001 *mt9m001 = to_mt9m001(client);
	const struct mt9m001_datafmt *fmt;

	if (format->pad)
		return -EINVAL;

	v4l_bound_align_image(&mf->width, MT9M001_MIN_WIDTH,
		MT9M001_MAX_WIDTH, 1,
		&mf->height, MT9M001_MIN_HEIGHT + mt9m001->y_skip_top,
		MT9M001_MAX_HEIGHT + mt9m001->y_skip_top, 0, 0);

	if (mt9m001->fmts == mt9m001_colour_fmts)
		mf->height = ALIGN(mf->height - 1, 2);

	fmt = mt9m001_find_datafmt(mf->code, mt9m001->fmts,
				   mt9m001->num_fmts);
	if (!fmt) {
		fmt = mt9m001->fmt;
		mf->code = fmt->code;
	}

	mf->colorspace	= fmt->colorspace;
	mf->field	= V4L2_FIELD_NONE;
	mf->ycbcr_enc	= V4L2_YCBCR_ENC_DEFAULT;
	mf->quantization = V4L2_QUANTIZATION_DEFAULT;
	mf->xfer_func	= V4L2_XFER_FUNC_DEFAULT;

	if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE)
		return mt9m001_s_fmt(sd, fmt, mf);
	*v4l2_subdev_state_get_format(sd_state, 0) = *mf;
	return 0;
}

#ifdef CONFIG_VIDEO_ADV_DEBUG
static int mt9m001_g_register(struct v4l2_subdev *sd,
			      struct v4l2_dbg_register *reg)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);

	if (reg->reg > 0xff)
		return -EINVAL;

	reg->size = 2;
	reg->val = reg_read(client, reg->reg);

	if (reg->val > 0xffff)
		return -EIO;

	return 0;
}

static int mt9m001_s_register(struct v4l2_subdev *sd,
			      const struct v4l2_dbg_register *reg)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);

	if (reg->reg > 0xff)
		return -EINVAL;

	if (reg_write(client, reg->reg, reg->val) < 0)
		return -EIO;

	return 0;
}
#endif

static int mt9m001_power_on(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct mt9m001 *mt9m001 = to_mt9m001(client);
	int ret;

	ret = clk_prepare_enable(mt9m001->clk);
	if (ret)
		return ret;

	if (mt9m001->standby_gpio) {
		gpiod_set_value_cansleep(mt9m001->standby_gpio, 0);
		usleep_range(1000, 2000);
	}

	if (mt9m001->reset_gpio) {
		gpiod_set_value_cansleep(mt9m001->reset_gpio, 1);
		usleep_range(1000, 2000);
		gpiod_set_value_cansleep(mt9m001->reset_gpio, 0);
		usleep_range(1000, 2000);
	}

	return 0;
}

static int mt9m001_power_off(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct mt9m001 *mt9m001 = to_mt9m001(client);

	gpiod_set_value_cansleep(mt9m001->standby_gpio, 1);
	clk_disable_unprepare(mt9m001->clk);

	return 0;
}

static int mt9m001_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
{
	struct mt9m001 *mt9m001 = container_of(ctrl->handler,
					       struct mt9m001, hdl);
	s32 min, max;

	switch (ctrl->id) {
	case V4L2_CID_EXPOSURE_AUTO:
		min = mt9m001->exposure->minimum;
		max = mt9m001->exposure->maximum;
		mt9m001->exposure->val =
			(524 + (mt9m001->total_h - 1) * (max - min)) / 1048 + min;
		break;
	}
	return 0;
}

static int mt9m001_s_ctrl(struct v4l2_ctrl *ctrl)
{
	struct mt9m001 *mt9m001 = container_of(ctrl->handler,
					       struct mt9m001, hdl);
	struct v4l2_subdev *sd = &mt9m001->subdev;
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct v4l2_ctrl *exp = mt9m001->exposure;
	int data;
	int ret;

	if (!pm_runtime_get_if_in_use(&client->dev))
		return 0;

	switch (ctrl->id) {
	case V4L2_CID_VFLIP:
		if (ctrl->val)
			ret = reg_set(client, MT9M001_READ_OPTIONS2, 0x8000);
		else
			ret = reg_clear(client, MT9M001_READ_OPTIONS2, 0x8000);
		break;

	case V4L2_CID_GAIN:
		/* See Datasheet Table 7, Gain settings. */
		if (ctrl->val <= ctrl->default_value) {
			/* Pack it into 0..1 step 0.125, register values 0..8 */
			unsigned long range = ctrl->default_value - ctrl->minimum;
			data = ((ctrl->val - (s32)ctrl->minimum) * 8 + range / 2) / range;

			dev_dbg(&client->dev, "Setting gain %d\n", data);
			ret = reg_write(client, MT9M001_GLOBAL_GAIN, data);
		} else {
			/* Pack it into 1.125..15 variable step, register values 9..67 */
			/* We assume qctrl->maximum - qctrl->default_value - 1 > 0 */
			unsigned long range = ctrl->maximum - ctrl->default_value - 1;
			unsigned long gain = ((ctrl->val - (s32)ctrl->default_value - 1) *
					       111 + range / 2) / range + 9;

			if (gain <= 32)
				data = gain;
			else if (gain <= 64)
				data = ((gain - 32) * 16 + 16) / 32 + 80;
			else
				data = ((gain - 64) * 7 + 28) / 56 + 96;

			dev_dbg(&client->dev, "Setting gain from %d to %d\n",
				 reg_read(client, MT9M001_GLOBAL_GAIN), data);
			ret = reg_write(client, MT9M001_GLOBAL_GAIN, data);
		}
		break;

	case V4L2_CID_EXPOSURE_AUTO:
		if (ctrl->val == V4L2_EXPOSURE_MANUAL) {
			unsigned long range = exp->maximum - exp->minimum;
			unsigned long shutter = ((exp->val - (s32)exp->minimum) * 1048 +
						 range / 2) / range + 1;

			dev_dbg(&client->dev,
				"Setting shutter width from %d to %lu\n",
				reg_read(client, MT9M001_SHUTTER_WIDTH), shutter);
			ret = reg_write(client, MT9M001_SHUTTER_WIDTH, shutter);
		} else {
			mt9m001->total_h = mt9m001->rect.height +
				mt9m001->y_skip_top + MT9M001_DEFAULT_VBLANK;
			ret = reg_write(client, MT9M001_SHUTTER_WIDTH,
					mt9m001->total_h);
		}
		break;
	default:
		ret = -EINVAL;
		break;
	}

	pm_runtime_put(&client->dev);

	return ret;
}

/*
 * Interface active, can use i2c. If it fails, it can indeed mean, that
 * this wasn't our capture interface, so, we wait for the right one
 */
static int mt9m001_video_probe(struct i2c_client *client)
{
	struct mt9m001 *mt9m001 = to_mt9m001(client);
	s32 data;
	int ret;

	/* Enable the chip */
	data = reg_write(client, MT9M001_CHIP_ENABLE, 1);
	dev_dbg(&client->dev, "write: %d\n", data);

	/* Read out the chip version register */
	data = reg_read(client, MT9M001_CHIP_VERSION);

	/* must be 0x8411 or 0x8421 for colour sensor and 8431 for bw */
	switch (data) {
	case 0x8411:
	case 0x8421:
		mt9m001->fmts = mt9m001_colour_fmts;
		mt9m001->num_fmts = ARRAY_SIZE(mt9m001_colour_fmts);
		break;
	case 0x8431:
		mt9m001->fmts = mt9m001_monochrome_fmts;
		mt9m001->num_fmts = ARRAY_SIZE(mt9m001_monochrome_fmts);
		break;
	default:
		dev_err(&client->dev,
			"No MT9M001 chip detected, register read %x\n", data);
		ret = -ENODEV;
		goto done;
	}

	mt9m001->fmt = &mt9m001->fmts[0];

	dev_info(&client->dev, "Detected a MT9M001 chip ID %x (%s)\n", data,
		 data == 0x8431 ? "C12STM" : "C12ST");

	ret = mt9m001_init(client);
	if (ret < 0) {
		dev_err(&client->dev, "Failed to initialise the camera\n");
		goto done;
	}

	/* mt9m001_init() has reset the chip, returning registers to defaults */
	ret = v4l2_ctrl_handler_setup(&mt9m001->hdl);

done:
	return ret;
}

static int mt9m001_g_skip_top_lines(struct v4l2_subdev *sd, u32 *lines)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct mt9m001 *mt9m001 = to_mt9m001(client);

	*lines = mt9m001->y_skip_top;

	return 0;
}

static const struct v4l2_ctrl_ops mt9m001_ctrl_ops = {
	.g_volatile_ctrl = mt9m001_g_volatile_ctrl,
	.s_ctrl = mt9m001_s_ctrl,
};

static const struct v4l2_subdev_core_ops mt9m001_subdev_core_ops = {
	.log_status = v4l2_ctrl_subdev_log_status,
	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
#ifdef CONFIG_VIDEO_ADV_DEBUG
	.g_register	= mt9m001_g_register,
	.s_register	= mt9m001_s_register,
#endif
};

static int mt9m001_init_state(struct v4l2_subdev *sd,
			      struct v4l2_subdev_state *sd_state)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct mt9m001 *mt9m001 = to_mt9m001(client);
	struct v4l2_mbus_framefmt *try_fmt =
		v4l2_subdev_state_get_format(sd_state, 0);

	try_fmt->width		= MT9M001_MAX_WIDTH;
	try_fmt->height		= MT9M001_MAX_HEIGHT;
	try_fmt->code		= mt9m001->fmts[0].code;
	try_fmt->colorspace	= mt9m001->fmts[0].colorspace;
	try_fmt->field		= V4L2_FIELD_NONE;
	try_fmt->ycbcr_enc	= V4L2_YCBCR_ENC_DEFAULT;
	try_fmt->quantization	= V4L2_QUANTIZATION_DEFAULT;
	try_fmt->xfer_func	= V4L2_XFER_FUNC_DEFAULT;

	return 0;
}

static int mt9m001_enum_mbus_code(struct v4l2_subdev *sd,
		struct v4l2_subdev_state *sd_state,
		struct v4l2_subdev_mbus_code_enum *code)
{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct mt9m001 *mt9m001 = to_mt9m001(client);

	if (code->pad || code->index >= mt9m001->num_fmts)
		return -EINVAL;

	code->code = mt9m001->fmts[code->index].code;
	return 0;
}

static int mt9m001_get_mbus_config(struct v4l2_subdev *sd,
				   unsigned int pad,
				   struct v4l2_mbus_config *cfg)
{
	/* MT9M001 has all capture_format parameters fixed */
	cfg->type = V4L2_MBUS_PARALLEL;
	cfg->bus.parallel.flags = V4L2_MBUS_PCLK_SAMPLE_FALLING |
				  V4L2_MBUS_HSYNC_ACTIVE_HIGH |
				  V4L2_MBUS_VSYNC_ACTIVE_HIGH |
				  V4L2_MBUS_DATA_ACTIVE_HIGH |
				  V4L2_MBUS_MASTER;

	return 0;
}

static const struct v4l2_subdev_video_ops mt9m001_subdev_video_ops = {
	.s_stream	= mt9m001_s_stream,
};

static const struct v4l2_subdev_sensor_ops mt9m001_subdev_sensor_ops = {
	.g_skip_top_lines	= mt9m001_g_skip_top_lines,
};

static const struct v4l2_subdev_pad_ops mt9m001_subdev_pad_ops = {
	.enum_mbus_code = mt9m001_enum_mbus_code,
	.get_selection	= mt9m001_get_selection,
	.set_selection	= mt9m001_set_selection,
	.get_fmt	= mt9m001_get_fmt,
	.set_fmt	= mt9m001_set_fmt,
	.get_mbus_config = mt9m001_get_mbus_config,
};

static const struct v4l2_subdev_ops mt9m001_subdev_ops = {
	.core	= &mt9m001_subdev_core_ops,
	.video	= &mt9m001_subdev_video_ops,
	.sensor	= &mt9m001_subdev_sensor_ops,
	.pad	= &mt9m001_subdev_pad_ops,
};

static const struct v4l2_subdev_internal_ops mt9m001_internal_ops = {
	.init_state	= mt9m001_init_state,
};

static int mt9m001_probe(struct i2c_client *client)
{
	struct mt9m001 *mt9m001;
	struct i2c_adapter *adapter = client->adapter;
	int ret;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) {
		dev_warn(&adapter->dev,
			 "I2C-Adapter doesn't support I2C_FUNC_SMBUS_WORD\n");
		return -EIO;
	}

	mt9m001 = devm_kzalloc(&client->dev, sizeof(*mt9m001), GFP_KERNEL);
	if (!mt9m001)
		return -ENOMEM;

	mt9m001->clk = devm_clk_get(&client->dev, NULL);
	if (IS_ERR(mt9m001->clk))
		return PTR_ERR(mt9m001->clk);

	mt9m001->standby_gpio = devm_gpiod_get_optional(&client->dev, "standby",
							GPIOD_OUT_LOW);
	if (IS_ERR(mt9m001->standby_gpio))
		return PTR_ERR(mt9m001->standby_gpio);

	mt9m001->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
						      GPIOD_OUT_LOW);
	if (IS_ERR(mt9m001->reset_gpio))
		return PTR_ERR(mt9m001->reset_gpio);

	v4l2_i2c_subdev_init(&mt9m001->subdev, client, &mt9m001_subdev_ops);
	mt9m001->subdev.internal_ops = &mt9m001_internal_ops;
	mt9m001->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
				 V4L2_SUBDEV_FL_HAS_EVENTS;
	v4l2_ctrl_handler_init(&mt9m001->hdl, 4);
	v4l2_ctrl_new_std(&mt9m001->hdl, &mt9m001_ctrl_ops,
			V4L2_CID_VFLIP, 0, 1, 1, 0);
	v4l2_ctrl_new_std(&mt9m001->hdl, &mt9m001_ctrl_ops,
			V4L2_CID_GAIN, 0, 127, 1, 64);
	mt9m001->exposure = v4l2_ctrl_new_std(&mt9m001->hdl, &mt9m001_ctrl_ops,
			V4L2_CID_EXPOSURE, 1, 255, 1, 255);
	/*
	 * Simulated autoexposure. If enabled, we calculate shutter width
	 * ourselves in the driver based on vertical blanking and frame width
	 */
	mt9m001->autoexposure = v4l2_ctrl_new_std_menu(&mt9m001->hdl,
			&mt9m001_ctrl_ops, V4L2_CID_EXPOSURE_AUTO, 1, 0,
			V4L2_EXPOSURE_AUTO);
	mt9m001->subdev.ctrl_handler = &mt9m001->hdl;
	if (mt9m001->hdl.error)
		return mt9m001->hdl.error;

	v4l2_ctrl_auto_cluster(2, &mt9m001->autoexposure,
					V4L2_EXPOSURE_MANUAL, true);

	mutex_init(&mt9m001->mutex);
	mt9m001->hdl.lock = &mt9m001->mutex;

	/* Second stage probe - when a capture adapter is there */
	mt9m001->y_skip_top	= 0;
	mt9m001->rect.left	= MT9M001_COLUMN_SKIP;
	mt9m001->rect.top	= MT9M001_ROW_SKIP;
	mt9m001->rect.width	= MT9M001_MAX_WIDTH;
	mt9m001->rect.height	= MT9M001_MAX_HEIGHT;

	ret = mt9m001_power_on(&client->dev);
	if (ret)
		goto error_hdl_free;

	pm_runtime_set_active(&client->dev);
	pm_runtime_enable(&client->dev);

	ret = mt9m001_video_probe(client);
	if (ret)
		goto error_power_off;

	mt9m001->pad.flags = MEDIA_PAD_FL_SOURCE;
	mt9m001->subdev.entity.function = MEDIA_ENT_F_CAM_SENSOR;
	ret = media_entity_pads_init(&mt9m001->subdev.entity, 1, &mt9m001->pad);
	if (ret)
		goto error_power_off;

	ret = v4l2_async_register_subdev(&mt9m001->subdev);
	if (ret)
		goto error_entity_cleanup;

	pm_runtime_idle(&client->dev);

	return 0;

error_entity_cleanup:
	media_entity_cleanup(&mt9m001->subdev.entity);
error_power_off:
	pm_runtime_disable(&client->dev);
	pm_runtime_set_suspended(&client->dev);
	mt9m001_power_off(&client->dev);

error_hdl_free:
	v4l2_ctrl_handler_free(&mt9m001->hdl);
	mutex_destroy(&mt9m001->mutex);

	return ret;
}

static void mt9m001_remove(struct i2c_client *client)
{
	struct mt9m001 *mt9m001 = to_mt9m001(client);

	/*
	 * As it increments RPM usage_count even on errors, we don't need to
	 * check the returned code here.
	 */
	pm_runtime_get_sync(&client->dev);

	v4l2_async_unregister_subdev(&mt9m001->subdev);
	media_entity_cleanup(&mt9m001->subdev.entity);

	pm_runtime_disable(&client->dev);
	pm_runtime_set_suspended(&client->dev);
	pm_runtime_put_noidle(&client->dev);
	mt9m001_power_off(&client->dev);

	v4l2_ctrl_handler_free(&mt9m001->hdl);
	mutex_destroy(&mt9m001->mutex);
}

static const struct i2c_device_id mt9m001_id[] = {
	{ "mt9m001" },
	{ }
};
MODULE_DEVICE_TABLE(i2c, mt9m001_id);

static const struct dev_pm_ops mt9m001_pm_ops = {
	SET_RUNTIME_PM_OPS(mt9m001_power_off, mt9m001_power_on, NULL)
};

static const struct of_device_id mt9m001_of_match[] = {
	{ .compatible = "onnn,mt9m001", },
	{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, mt9m001_of_match);

static struct i2c_driver mt9m001_i2c_driver = {
	.driver = {
		.name = "mt9m001",
		.pm = &mt9m001_pm_ops,
		.of_match_table = mt9m001_of_match,
	},
	.probe		= mt9m001_probe,
	.remove		= mt9m001_remove,
	.id_table	= mt9m001_id,
};

module_i2c_driver(mt9m001_i2c_driver);

MODULE_DESCRIPTION("Micron MT9M001 Camera driver");
MODULE_AUTHOR("Guennadi Liakhovetski <kernel@pengutronix.de>");
MODULE_LICENSE("GPL v2");