summaryrefslogtreecommitdiff
path: root/drivers/media/video/mt9m001.c
blob: 0c524376b67e66baa4f67ddcf262a647a02143e1 (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
/*
 * Driver for MT9M001 CMOS Image Sensor from Micron
 *
 * Copyright (C) 2008, Guennadi Liakhovetski <kernel@pengutronix.de>
 *
 * 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.
 */

#include <linux/videodev2.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/log2.h>
#include <linux/gpio.h>

#include <media/v4l2-common.h>
#include <media/v4l2-chip-ident.h>
#include <media/soc_camera.h>

/* mt9m001 i2c address 0x5d
 * The platform has to define i2c_board_info
 * and call i2c_register_board_info() */

/* 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

static const struct soc_camera_data_format mt9m001_colour_formats[] = {
	/* Order important: first natively supported,
	 * second supported with a GPIO extender */
	{
		.name		= "Bayer (sRGB) 10 bit",
		.depth		= 10,
		.fourcc		= V4L2_PIX_FMT_SBGGR16,
		.colorspace	= V4L2_COLORSPACE_SRGB,
	}, {
		.name		= "Bayer (sRGB) 8 bit",
		.depth		= 8,
		.fourcc		= V4L2_PIX_FMT_SBGGR8,
		.colorspace	= V4L2_COLORSPACE_SRGB,
	}
};

static const struct soc_camera_data_format mt9m001_monochrome_formats[] = {
	/* Order important - see above */
	{
		.name		= "Monochrome 10 bit",
		.depth		= 10,
		.fourcc		= V4L2_PIX_FMT_Y16,
	}, {
		.name		= "Monochrome 8 bit",
		.depth		= 8,
		.fourcc		= V4L2_PIX_FMT_GREY,
	},
};

struct mt9m001 {
	struct i2c_client *client;
	struct soc_camera_device icd;
	int model;	/* V4L2_IDENT_MT9M001* codes from v4l2-chip-ident.h */
	int switch_gpio;
	unsigned char autoexposure;
	unsigned char datawidth;
};

static int reg_read(struct soc_camera_device *icd, const u8 reg)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
	struct i2c_client *client = mt9m001->client;
	s32 data = i2c_smbus_read_word_data(client, reg);
	return data < 0 ? data : swab16(data);
}

static int reg_write(struct soc_camera_device *icd, const u8 reg,
		     const u16 data)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
	return i2c_smbus_write_word_data(mt9m001->client, reg, swab16(data));
}

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

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

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

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

static int mt9m001_init(struct soc_camera_device *icd)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
	struct soc_camera_link *icl = mt9m001->client->dev.platform_data;
	int ret;

	dev_dbg(icd->vdev->parent, "%s\n", __func__);

	if (icl->power) {
		ret = icl->power(&mt9m001->client->dev, 1);
		if (ret < 0) {
			dev_err(icd->vdev->parent,
				"Platform failed to power-on the camera.\n");
			return ret;
		}
	}

	/* The camera could have been already on, we reset it additionally */
	if (icl->reset)
		ret = icl->reset(&mt9m001->client->dev);
	else
		ret = -ENODEV;

	if (ret < 0) {
		/* Either no platform reset, or platform reset failed */
		ret = reg_write(icd, MT9M001_RESET, 1);
		if (!ret)
			ret = reg_write(icd, MT9M001_RESET, 0);
	}
	/* Disable chip, synchronous option update */
	if (!ret)
		ret = reg_write(icd, MT9M001_OUTPUT_CONTROL, 0);

	return ret;
}

static int mt9m001_release(struct soc_camera_device *icd)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
	struct soc_camera_link *icl = mt9m001->client->dev.platform_data;

	/* Disable the chip */
	reg_write(icd, MT9M001_OUTPUT_CONTROL, 0);

	if (icl->power)
		icl->power(&mt9m001->client->dev, 0);

	return 0;
}

static int mt9m001_start_capture(struct soc_camera_device *icd)
{
	/* Switch to master "normal" mode */
	if (reg_write(icd, MT9M001_OUTPUT_CONTROL, 2) < 0)
		return -EIO;
	return 0;
}

static int mt9m001_stop_capture(struct soc_camera_device *icd)
{
	/* Stop sensor readout */
	if (reg_write(icd, MT9M001_OUTPUT_CONTROL, 0) < 0)
		return -EIO;
	return 0;
}

static int bus_switch_request(struct mt9m001 *mt9m001,
			      struct soc_camera_link *icl)
{
#ifdef CONFIG_MT9M001_PCA9536_SWITCH
	int ret;
	unsigned int gpio = icl->gpio;

	if (gpio_is_valid(gpio)) {
		/* We have a data bus switch. */
		ret = gpio_request(gpio, "mt9m001");
		if (ret < 0) {
			dev_err(&mt9m001->client->dev, "Cannot get GPIO %u\n",
				gpio);
			return ret;
		}

		ret = gpio_direction_output(gpio, 0);
		if (ret < 0) {
			dev_err(&mt9m001->client->dev,
				"Cannot set GPIO %u to output\n", gpio);
			gpio_free(gpio);
			return ret;
		}
	}

	mt9m001->switch_gpio = gpio;
#else
	mt9m001->switch_gpio = -EINVAL;
#endif
	return 0;
}

static void bus_switch_release(struct mt9m001 *mt9m001)
{
#ifdef CONFIG_MT9M001_PCA9536_SWITCH
	if (gpio_is_valid(mt9m001->switch_gpio))
		gpio_free(mt9m001->switch_gpio);
#endif
}

static int bus_switch_act(struct mt9m001 *mt9m001, int go8bit)
{
#ifdef CONFIG_MT9M001_PCA9536_SWITCH
	if (!gpio_is_valid(mt9m001->switch_gpio))
		return -ENODEV;

	gpio_set_value_cansleep(mt9m001->switch_gpio, go8bit);
	return 0;
#else
	return -ENODEV;
#endif
}

static int bus_switch_possible(struct mt9m001 *mt9m001)
{
#ifdef CONFIG_MT9M001_PCA9536_SWITCH
	return gpio_is_valid(mt9m001->switch_gpio);
#else
	return 0;
#endif
}

static int mt9m001_set_bus_param(struct soc_camera_device *icd,
				 unsigned long flags)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
	unsigned int width_flag = flags & SOCAM_DATAWIDTH_MASK;
	int ret;

	/* Flags validity verified in test_bus_param */

	if ((mt9m001->datawidth != 10 && (width_flag == SOCAM_DATAWIDTH_10)) ||
	    (mt9m001->datawidth != 9  && (width_flag == SOCAM_DATAWIDTH_9)) ||
	    (mt9m001->datawidth != 8  && (width_flag == SOCAM_DATAWIDTH_8))) {
		/* Well, we actually only can do 10 or 8 bits... */
		if (width_flag == SOCAM_DATAWIDTH_9)
			return -EINVAL;
		ret = bus_switch_act(mt9m001,
				     width_flag == SOCAM_DATAWIDTH_8);
		if (ret < 0)
			return ret;

		mt9m001->datawidth = width_flag == SOCAM_DATAWIDTH_8 ? 8 : 10;
	}

	return 0;
}

static unsigned long mt9m001_query_bus_param(struct soc_camera_device *icd)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
	unsigned int width_flag = SOCAM_DATAWIDTH_10;

	if (bus_switch_possible(mt9m001))
		width_flag |= SOCAM_DATAWIDTH_8;

	/* MT9M001 has all capture_format parameters fixed */
	return SOCAM_PCLK_SAMPLE_RISING |
		SOCAM_HSYNC_ACTIVE_HIGH |
		SOCAM_VSYNC_ACTIVE_HIGH |
		SOCAM_MASTER |
		width_flag;
}

static int mt9m001_set_fmt_cap(struct soc_camera_device *icd,
		__u32 pixfmt, struct v4l2_rect *rect)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
	int ret;
	const u16 hblank = 9, vblank = 25;

	/* Blanking and start values - default... */
	ret = reg_write(icd, MT9M001_HORIZONTAL_BLANKING, hblank);
	if (!ret)
		ret = reg_write(icd, MT9M001_VERTICAL_BLANKING, vblank);

	/* The caller provides a supported format, as verified per
	 * call to icd->try_fmt_cap() */
	if (!ret)
		ret = reg_write(icd, MT9M001_COLUMN_START, rect->left);
	if (!ret)
		ret = reg_write(icd, MT9M001_ROW_START, rect->top);
	if (!ret)
		ret = reg_write(icd, MT9M001_WINDOW_WIDTH, rect->width - 1);
	if (!ret)
		ret = reg_write(icd, MT9M001_WINDOW_HEIGHT,
				rect->height + icd->y_skip_top - 1);
	if (!ret && mt9m001->autoexposure) {
		ret = reg_write(icd, MT9M001_SHUTTER_WIDTH,
				rect->height + icd->y_skip_top + vblank);
		if (!ret) {
			const struct v4l2_queryctrl *qctrl =
				soc_camera_find_qctrl(icd->ops,
						      V4L2_CID_EXPOSURE);
			icd->exposure = (524 + (rect->height + icd->y_skip_top +
						vblank - 1) *
					 (qctrl->maximum - qctrl->minimum)) /
				1048 + qctrl->minimum;
		}
	}

	return ret;
}

static int mt9m001_try_fmt_cap(struct soc_camera_device *icd,
			       struct v4l2_format *f)
{
	if (f->fmt.pix.height < 32 + icd->y_skip_top)
		f->fmt.pix.height = 32 + icd->y_skip_top;
	if (f->fmt.pix.height > 1024 + icd->y_skip_top)
		f->fmt.pix.height = 1024 + icd->y_skip_top;
	if (f->fmt.pix.width < 48)
		f->fmt.pix.width = 48;
	if (f->fmt.pix.width > 1280)
		f->fmt.pix.width = 1280;
	f->fmt.pix.width &= ~0x01; /* has to be even, unsure why was ~3 */

	return 0;
}

static int mt9m001_get_chip_id(struct soc_camera_device *icd,
			       struct v4l2_chip_ident *id)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);

	if (id->match_type != V4L2_CHIP_MATCH_I2C_ADDR)
		return -EINVAL;

	if (id->match_chip != mt9m001->client->addr)
		return -ENODEV;

	id->ident	= mt9m001->model;
	id->revision	= 0;

	return 0;
}

#ifdef CONFIG_VIDEO_ADV_DEBUG
static int mt9m001_get_register(struct soc_camera_device *icd,
				struct v4l2_register *reg)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);

	if (reg->match_type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
		return -EINVAL;

	if (reg->match_chip != mt9m001->client->addr)
		return -ENODEV;

	reg->val = reg_read(icd, reg->reg);

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

	return 0;
}

static int mt9m001_set_register(struct soc_camera_device *icd,
				struct v4l2_register *reg)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);

	if (reg->match_type != V4L2_CHIP_MATCH_I2C_ADDR || reg->reg > 0xff)
		return -EINVAL;

	if (reg->match_chip != mt9m001->client->addr)
		return -ENODEV;

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

	return 0;
}
#endif

static const struct v4l2_queryctrl mt9m001_controls[] = {
	{
		.id		= V4L2_CID_VFLIP,
		.type		= V4L2_CTRL_TYPE_BOOLEAN,
		.name		= "Flip Vertically",
		.minimum	= 0,
		.maximum	= 1,
		.step		= 1,
		.default_value	= 0,
	}, {
		.id		= V4L2_CID_GAIN,
		.type		= V4L2_CTRL_TYPE_INTEGER,
		.name		= "Gain",
		.minimum	= 0,
		.maximum	= 127,
		.step		= 1,
		.default_value	= 64,
		.flags		= V4L2_CTRL_FLAG_SLIDER,
	}, {
		.id		= V4L2_CID_EXPOSURE,
		.type		= V4L2_CTRL_TYPE_INTEGER,
		.name		= "Exposure",
		.minimum	= 1,
		.maximum	= 255,
		.step		= 1,
		.default_value	= 255,
		.flags		= V4L2_CTRL_FLAG_SLIDER,
	}, {
		.id		= V4L2_CID_EXPOSURE_AUTO,
		.type		= V4L2_CTRL_TYPE_BOOLEAN,
		.name		= "Automatic Exposure",
		.minimum	= 0,
		.maximum	= 1,
		.step		= 1,
		.default_value	= 1,
	}
};

static int mt9m001_video_probe(struct soc_camera_device *);
static void mt9m001_video_remove(struct soc_camera_device *);
static int mt9m001_get_control(struct soc_camera_device *, struct v4l2_control *);
static int mt9m001_set_control(struct soc_camera_device *, struct v4l2_control *);

static struct soc_camera_ops mt9m001_ops = {
	.owner			= THIS_MODULE,
	.probe			= mt9m001_video_probe,
	.remove			= mt9m001_video_remove,
	.init			= mt9m001_init,
	.release		= mt9m001_release,
	.start_capture		= mt9m001_start_capture,
	.stop_capture		= mt9m001_stop_capture,
	.set_fmt_cap		= mt9m001_set_fmt_cap,
	.try_fmt_cap		= mt9m001_try_fmt_cap,
	.set_bus_param		= mt9m001_set_bus_param,
	.query_bus_param	= mt9m001_query_bus_param,
	.controls		= mt9m001_controls,
	.num_controls		= ARRAY_SIZE(mt9m001_controls),
	.get_control		= mt9m001_get_control,
	.set_control		= mt9m001_set_control,
	.get_chip_id		= mt9m001_get_chip_id,
#ifdef CONFIG_VIDEO_ADV_DEBUG
	.get_register		= mt9m001_get_register,
	.set_register		= mt9m001_set_register,
#endif
};

static int mt9m001_get_control(struct soc_camera_device *icd, struct v4l2_control *ctrl)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
	int data;

	switch (ctrl->id) {
	case V4L2_CID_VFLIP:
		data = reg_read(icd, MT9M001_READ_OPTIONS2);
		if (data < 0)
			return -EIO;
		ctrl->value = !!(data & 0x8000);
		break;
	case V4L2_CID_EXPOSURE_AUTO:
		ctrl->value = mt9m001->autoexposure;
		break;
	}
	return 0;
}

static int mt9m001_set_control(struct soc_camera_device *icd, struct v4l2_control *ctrl)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
	const struct v4l2_queryctrl *qctrl;
	int data;

	qctrl = soc_camera_find_qctrl(&mt9m001_ops, ctrl->id);

	if (!qctrl)
		return -EINVAL;

	switch (ctrl->id) {
	case V4L2_CID_VFLIP:
		if (ctrl->value)
			data = reg_set(icd, MT9M001_READ_OPTIONS2, 0x8000);
		else
			data = reg_clear(icd, MT9M001_READ_OPTIONS2, 0x8000);
		if (data < 0)
			return -EIO;
		break;
	case V4L2_CID_GAIN:
		if (ctrl->value > qctrl->maximum || ctrl->value < qctrl->minimum)
			return -EINVAL;
		/* See Datasheet Table 7, Gain settings. */
		if (ctrl->value <= qctrl->default_value) {
			/* Pack it into 0..1 step 0.125, register values 0..8 */
			unsigned long range = qctrl->default_value - qctrl->minimum;
			data = ((ctrl->value - qctrl->minimum) * 8 + range / 2) / range;

			dev_dbg(&icd->dev, "Setting gain %d\n", data);
			data = reg_write(icd, MT9M001_GLOBAL_GAIN, data);
			if (data < 0)
				return -EIO;
		} 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 = qctrl->maximum - qctrl->default_value - 1;
			unsigned long gain = ((ctrl->value - qctrl->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(&icd->dev, "Setting gain from %d to %d\n",
				 reg_read(icd, MT9M001_GLOBAL_GAIN), data);
			data = reg_write(icd, MT9M001_GLOBAL_GAIN, data);
			if (data < 0)
				return -EIO;
		}

		/* Success */
		icd->gain = ctrl->value;
		break;
	case V4L2_CID_EXPOSURE:
		/* mt9m001 has maximum == default */
		if (ctrl->value > qctrl->maximum || ctrl->value < qctrl->minimum)
			return -EINVAL;
		else {
			unsigned long range = qctrl->maximum - qctrl->minimum;
			unsigned long shutter = ((ctrl->value - qctrl->minimum) * 1048 +
						 range / 2) / range + 1;

			dev_dbg(&icd->dev, "Setting shutter width from %d to %lu\n",
				 reg_read(icd, MT9M001_SHUTTER_WIDTH), shutter);
			if (reg_write(icd, MT9M001_SHUTTER_WIDTH, shutter) < 0)
				return -EIO;
			icd->exposure = ctrl->value;
			mt9m001->autoexposure = 0;
		}
		break;
	case V4L2_CID_EXPOSURE_AUTO:
		if (ctrl->value) {
			const u16 vblank = 25;
			if (reg_write(icd, MT9M001_SHUTTER_WIDTH, icd->height +
				      icd->y_skip_top + vblank) < 0)
				return -EIO;
			qctrl = soc_camera_find_qctrl(icd->ops, V4L2_CID_EXPOSURE);
			icd->exposure = (524 + (icd->height + icd->y_skip_top + vblank - 1) *
					 (qctrl->maximum - qctrl->minimum)) /
				1048 + qctrl->minimum;
			mt9m001->autoexposure = 1;
		} else
			mt9m001->autoexposure = 0;
		break;
	}
	return 0;
}

/* 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 soc_camera_device *icd)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);
	s32 data;
	int ret;

	/* We must have a parent by now. And it cannot be a wrong one.
	 * So this entire test is completely redundant. */
	if (!icd->dev.parent ||
	    to_soc_camera_host(icd->dev.parent)->nr != icd->iface)
		return -ENODEV;

	/* Enable the chip */
	data = reg_write(&mt9m001->icd, MT9M001_CHIP_ENABLE, 1);
	dev_dbg(&icd->dev, "write: %d\n", data);

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

	/* must be 0x8411 or 0x8421 for colour sensor and 8431 for bw */
	switch (data) {
	case 0x8411:
	case 0x8421:
		mt9m001->model = V4L2_IDENT_MT9M001C12ST;
		icd->formats = mt9m001_colour_formats;
		if (mt9m001->client->dev.platform_data)
			icd->num_formats = ARRAY_SIZE(mt9m001_colour_formats);
		else
			icd->num_formats = 1;
		break;
	case 0x8431:
		mt9m001->model = V4L2_IDENT_MT9M001C12STM;
		icd->formats = mt9m001_monochrome_formats;
		if (mt9m001->client->dev.platform_data)
			icd->num_formats = ARRAY_SIZE(mt9m001_monochrome_formats);
		else
			icd->num_formats = 1;
		break;
	default:
		ret = -ENODEV;
		dev_err(&icd->dev,
			"No MT9M001 chip detected, register read %x\n", data);
		goto ei2c;
	}

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

	/* Now that we know the model, we can start video */
	ret = soc_camera_video_start(icd);
	if (ret)
		goto eisis;

	return 0;

eisis:
ei2c:
	return ret;
}

static void mt9m001_video_remove(struct soc_camera_device *icd)
{
	struct mt9m001 *mt9m001 = container_of(icd, struct mt9m001, icd);

	dev_dbg(&icd->dev, "Video %x removed: %p, %p\n", mt9m001->client->addr,
		mt9m001->icd.dev.parent, mt9m001->icd.vdev);
	soc_camera_video_stop(&mt9m001->icd);
}

static int mt9m001_probe(struct i2c_client *client,
			 const struct i2c_device_id *did)
{
	struct mt9m001 *mt9m001;
	struct soc_camera_device *icd;
	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
	struct soc_camera_link *icl = client->dev.platform_data;
	int ret;

	if (!icl) {
		dev_err(&client->dev, "MT9M001 driver needs platform data\n");
		return -EINVAL;
	}

	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 = kzalloc(sizeof(struct mt9m001), GFP_KERNEL);
	if (!mt9m001)
		return -ENOMEM;

	mt9m001->client = client;
	i2c_set_clientdata(client, mt9m001);

	/* Second stage probe - when a capture adapter is there */
	icd = &mt9m001->icd;
	icd->ops	= &mt9m001_ops;
	icd->control	= &client->dev;
	icd->x_min	= 20;
	icd->y_min	= 12;
	icd->x_current	= 20;
	icd->y_current	= 12;
	icd->width_min	= 48;
	icd->width_max	= 1280;
	icd->height_min	= 32;
	icd->height_max	= 1024;
	icd->y_skip_top	= 1;
	icd->iface	= icl->bus_id;
	/* Default datawidth - this is the only width this camera (normally)
	 * supports. It is only with extra logic that it can support
	 * other widths. Therefore it seems to be a sensible default. */
	mt9m001->datawidth = 10;
	/* Simulated autoexposure. If enabled, we calculate shutter width
	 * ourselves in the driver based on vertical blanking and frame width */
	mt9m001->autoexposure = 1;

	ret = bus_switch_request(mt9m001, icl);
	if (ret)
		goto eswinit;

	ret = soc_camera_device_register(icd);
	if (ret)
		goto eisdr;

	return 0;

eisdr:
	bus_switch_release(mt9m001);
eswinit:
	kfree(mt9m001);
	return ret;
}

static int mt9m001_remove(struct i2c_client *client)
{
	struct mt9m001 *mt9m001 = i2c_get_clientdata(client);

	soc_camera_device_unregister(&mt9m001->icd);
	bus_switch_release(mt9m001);
	kfree(mt9m001);

	return 0;
}

static const struct i2c_device_id mt9m001_id[] = {
	{ "mt9m001", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, mt9m001_id);

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

static int __init mt9m001_mod_init(void)
{
	return i2c_add_driver(&mt9m001_i2c_driver);
}

static void __exit mt9m001_mod_exit(void)
{
	i2c_del_driver(&mt9m001_i2c_driver);
}

module_init(mt9m001_mod_init);
module_exit(mt9m001_mod_exit);

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