summaryrefslogtreecommitdiff
path: root/drivers/media/platform/qcom/camss/camss-csid.c
blob: cc11fbfdae132a9d7a8066f9453233bd218724f5 (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
// SPDX-License-Identifier: GPL-2.0
/*
 * camss-csid.c
 *
 * Qualcomm MSM Camera Subsystem - CSID (CSI Decoder) Module
 *
 * Copyright (c) 2011-2015, The Linux Foundation. All rights reserved.
 * Copyright (C) 2015-2018 Linaro Ltd.
 */
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <media/media-entity.h>
#include <media/v4l2-device.h>
#include <media/v4l2-event.h>
#include <media/v4l2-subdev.h>

#include "camss-csid.h"
#include "camss-csid-gen1.h"
#include "camss.h"

#define MSM_CSID_NAME "msm_csid"

const char * const csid_testgen_modes[] = {
	"Disabled",
	"Incrementing",
	"Alternating 0x55/0xAA",
	"All Zeros 0x00",
	"All Ones 0xFF",
	"Pseudo-random Data",
	"User Specified",
	"Complex pattern",
	"Color box",
	"Color bars",
	NULL
};

u32 csid_find_code(u32 *codes, unsigned int ncodes,
		   unsigned int match_format_idx, u32 match_code)
{
	int i;

	if (!match_code && (match_format_idx >= ncodes))
		return 0;

	for (i = 0; i < ncodes; i++)
		if (match_code) {
			if (codes[i] == match_code)
				return match_code;
		} else {
			if (i == match_format_idx)
				return codes[i];
		}

	return codes[0];
}

const struct csid_format *csid_get_fmt_entry(const struct csid_format *formats,
					     unsigned int nformats,
					     u32 code)
{
	unsigned int i;

	for (i = 0; i < nformats; i++)
		if (code == formats[i].code)
			return &formats[i];

	WARN(1, "Unknown format\n");

	return &formats[0];
}

/*
 * csid_set_clock_rates - Calculate and set clock rates on CSID module
 * @csiphy: CSID device
 */
static int csid_set_clock_rates(struct csid_device *csid)
{
	struct device *dev = csid->camss->dev;
	const struct csid_format *fmt;
	s64 link_freq;
	int i, j;
	int ret;

	fmt = csid_get_fmt_entry(csid->formats, csid->nformats,
				 csid->fmt[MSM_CSIPHY_PAD_SINK].code);
	link_freq = camss_get_link_freq(&csid->subdev.entity, fmt->bpp,
					csid->phy.lane_cnt);
	if (link_freq < 0)
		link_freq = 0;

	for (i = 0; i < csid->nclocks; i++) {
		struct camss_clock *clock = &csid->clock[i];

		if (!strcmp(clock->name, "csi0") ||
		    !strcmp(clock->name, "csi1") ||
		    !strcmp(clock->name, "csi2") ||
		    !strcmp(clock->name, "csi3")) {
			u64 min_rate = link_freq / 4;
			long rate;

			camss_add_clock_margin(&min_rate);

			for (j = 0; j < clock->nfreqs; j++)
				if (min_rate < clock->freq[j])
					break;

			if (j == clock->nfreqs) {
				dev_err(dev,
					"Pixel clock is too high for CSID\n");
				return -EINVAL;
			}

			/* if sensor pixel clock is not available */
			/* set highest possible CSID clock rate */
			if (min_rate == 0)
				j = clock->nfreqs - 1;

			rate = clk_round_rate(clock->clk, clock->freq[j]);
			if (rate < 0) {
				dev_err(dev, "clk round rate failed: %ld\n",
					rate);
				return -EINVAL;
			}

			ret = clk_set_rate(clock->clk, rate);
			if (ret < 0) {
				dev_err(dev, "clk set rate failed: %d\n", ret);
				return ret;
			}
		} else if (clock->nfreqs) {
			clk_set_rate(clock->clk, clock->freq[0]);
		}
	}

	return 0;
}

/*
 * csid_set_power - Power on/off CSID module
 * @sd: CSID V4L2 subdevice
 * @on: Requested power state
 *
 * Return 0 on success or a negative error code otherwise
 */
static int csid_set_power(struct v4l2_subdev *sd, int on)
{
	struct csid_device *csid = v4l2_get_subdevdata(sd);
	struct device *dev = csid->camss->dev;
	int ret;

	if (on) {
		ret = pm_runtime_get_sync(dev);
		if (ret < 0) {
			pm_runtime_put_sync(dev);
			return ret;
		}

		ret = regulator_enable(csid->vdda);
		if (ret < 0) {
			pm_runtime_put_sync(dev);
			return ret;
		}

		ret = csid_set_clock_rates(csid);
		if (ret < 0) {
			regulator_disable(csid->vdda);
			pm_runtime_put_sync(dev);
			return ret;
		}

		ret = camss_enable_clocks(csid->nclocks, csid->clock, dev);
		if (ret < 0) {
			regulator_disable(csid->vdda);
			pm_runtime_put_sync(dev);
			return ret;
		}

		enable_irq(csid->irq);

		ret = csid->ops->reset(csid);
		if (ret < 0) {
			disable_irq(csid->irq);
			camss_disable_clocks(csid->nclocks, csid->clock);
			regulator_disable(csid->vdda);
			pm_runtime_put_sync(dev);
			return ret;
		}

		csid->ops->hw_version(csid);
	} else {
		disable_irq(csid->irq);
		camss_disable_clocks(csid->nclocks, csid->clock);
		ret = regulator_disable(csid->vdda);
		pm_runtime_put_sync(dev);
	}

	return ret;
}

/*
 * csid_set_stream - Enable/disable streaming on CSID module
 * @sd: CSID V4L2 subdevice
 * @enable: Requested streaming state
 *
 * Main configuration of CSID module is also done here.
 *
 * Return 0 on success or a negative error code otherwise
 */
static int csid_set_stream(struct v4l2_subdev *sd, int enable)
{
	struct csid_device *csid = v4l2_get_subdevdata(sd);
	int ret;

	if (enable) {
		ret = v4l2_ctrl_handler_setup(&csid->ctrls);
		if (ret < 0) {
			dev_err(csid->camss->dev,
				"could not sync v4l2 controls: %d\n", ret);
			return ret;
		}

		if (!csid->testgen.enabled &&
		    !media_entity_remote_pad(&csid->pads[MSM_CSID_PAD_SINK]))
			return -ENOLINK;
	}

	csid->ops->configure_stream(csid, enable);

	return 0;
}

/*
 * __csid_get_format - Get pointer to format structure
 * @csid: CSID device
 * @cfg: V4L2 subdev pad configuration
 * @pad: pad from which format is requested
 * @which: TRY or ACTIVE format
 *
 * Return pointer to TRY or ACTIVE format structure
 */
static struct v4l2_mbus_framefmt *
__csid_get_format(struct csid_device *csid,
		  struct v4l2_subdev_pad_config *cfg,
		  unsigned int pad,
		  enum v4l2_subdev_format_whence which)
{
	if (which == V4L2_SUBDEV_FORMAT_TRY)
		return v4l2_subdev_get_try_format(&csid->subdev, cfg, pad);

	return &csid->fmt[pad];
}

/*
 * csid_try_format - Handle try format by pad subdev method
 * @csid: CSID device
 * @cfg: V4L2 subdev pad configuration
 * @pad: pad on which format is requested
 * @fmt: pointer to v4l2 format structure
 * @which: wanted subdev format
 */
static void csid_try_format(struct csid_device *csid,
			    struct v4l2_subdev_pad_config *cfg,
			    unsigned int pad,
			    struct v4l2_mbus_framefmt *fmt,
			    enum v4l2_subdev_format_whence which)
{
	unsigned int i;

	switch (pad) {
	case MSM_CSID_PAD_SINK:
		/* Set format on sink pad */

		for (i = 0; i < csid->nformats; i++)
			if (fmt->code == csid->formats[i].code)
				break;

		/* If not found, use UYVY as default */
		if (i >= csid->nformats)
			fmt->code = MEDIA_BUS_FMT_UYVY8_2X8;

		fmt->width = clamp_t(u32, fmt->width, 1, 8191);
		fmt->height = clamp_t(u32, fmt->height, 1, 8191);

		fmt->field = V4L2_FIELD_NONE;
		fmt->colorspace = V4L2_COLORSPACE_SRGB;

		break;

	case MSM_CSID_PAD_SRC:
		if (csid->testgen_mode->cur.val == 0) {
			/* Test generator is disabled, */
			/* keep pad formats in sync */
			u32 code = fmt->code;

			*fmt = *__csid_get_format(csid, cfg,
						      MSM_CSID_PAD_SINK, which);
			fmt->code = csid->ops->src_pad_code(csid, fmt->code, 0, code);
		} else {
			/* Test generator is enabled, set format on source */
			/* pad to allow test generator usage */

			for (i = 0; i < csid->nformats; i++)
				if (csid->formats[i].code == fmt->code)
					break;

			/* If not found, use UYVY as default */
			if (i >= csid->nformats)
				fmt->code = MEDIA_BUS_FMT_UYVY8_2X8;

			fmt->width = clamp_t(u32, fmt->width, 1, 8191);
			fmt->height = clamp_t(u32, fmt->height, 1, 8191);

			fmt->field = V4L2_FIELD_NONE;
		}
		break;
	}

	fmt->colorspace = V4L2_COLORSPACE_SRGB;
}

/*
 * csid_enum_mbus_code - Handle pixel format enumeration
 * @sd: CSID V4L2 subdevice
 * @cfg: V4L2 subdev pad configuration
 * @code: pointer to v4l2_subdev_mbus_code_enum structure
 * return -EINVAL or zero on success
 */
static int csid_enum_mbus_code(struct v4l2_subdev *sd,
			       struct v4l2_subdev_pad_config *cfg,
			       struct v4l2_subdev_mbus_code_enum *code)
{
	struct csid_device *csid = v4l2_get_subdevdata(sd);

	if (code->pad == MSM_CSID_PAD_SINK) {
		if (code->index >= csid->nformats)
			return -EINVAL;

		code->code = csid->formats[code->index].code;
	} else {
		if (csid->testgen_mode->cur.val == 0) {
			struct v4l2_mbus_framefmt *sink_fmt;

			sink_fmt = __csid_get_format(csid, cfg,
						     MSM_CSID_PAD_SINK,
						     code->which);

			code->code = csid->ops->src_pad_code(csid, sink_fmt->code,
						       code->index, 0);
			if (!code->code)
				return -EINVAL;
		} else {
			if (code->index >= csid->nformats)
				return -EINVAL;

			code->code = csid->formats[code->index].code;
		}
	}

	return 0;
}

/*
 * csid_enum_frame_size - Handle frame size enumeration
 * @sd: CSID V4L2 subdevice
 * @cfg: V4L2 subdev pad configuration
 * @fse: pointer to v4l2_subdev_frame_size_enum structure
 * return -EINVAL or zero on success
 */
static int csid_enum_frame_size(struct v4l2_subdev *sd,
				struct v4l2_subdev_pad_config *cfg,
				struct v4l2_subdev_frame_size_enum *fse)
{
	struct csid_device *csid = v4l2_get_subdevdata(sd);
	struct v4l2_mbus_framefmt format;

	if (fse->index != 0)
		return -EINVAL;

	format.code = fse->code;
	format.width = 1;
	format.height = 1;
	csid_try_format(csid, cfg, fse->pad, &format, fse->which);
	fse->min_width = format.width;
	fse->min_height = format.height;

	if (format.code != fse->code)
		return -EINVAL;

	format.code = fse->code;
	format.width = -1;
	format.height = -1;
	csid_try_format(csid, cfg, fse->pad, &format, fse->which);
	fse->max_width = format.width;
	fse->max_height = format.height;

	return 0;
}

/*
 * csid_get_format - Handle get format by pads subdev method
 * @sd: CSID V4L2 subdevice
 * @cfg: V4L2 subdev pad configuration
 * @fmt: pointer to v4l2 subdev format structure
 *
 * Return -EINVAL or zero on success
 */
static int csid_get_format(struct v4l2_subdev *sd,
			   struct v4l2_subdev_pad_config *cfg,
			   struct v4l2_subdev_format *fmt)
{
	struct csid_device *csid = v4l2_get_subdevdata(sd);
	struct v4l2_mbus_framefmt *format;

	format = __csid_get_format(csid, cfg, fmt->pad, fmt->which);
	if (format == NULL)
		return -EINVAL;

	fmt->format = *format;

	return 0;
}

/*
 * csid_set_format - Handle set format by pads subdev method
 * @sd: CSID V4L2 subdevice
 * @cfg: V4L2 subdev pad configuration
 * @fmt: pointer to v4l2 subdev format structure
 *
 * Return -EINVAL or zero on success
 */
static int csid_set_format(struct v4l2_subdev *sd,
			   struct v4l2_subdev_pad_config *cfg,
			   struct v4l2_subdev_format *fmt)
{
	struct csid_device *csid = v4l2_get_subdevdata(sd);
	struct v4l2_mbus_framefmt *format;

	format = __csid_get_format(csid, cfg, fmt->pad, fmt->which);
	if (format == NULL)
		return -EINVAL;

	csid_try_format(csid, cfg, fmt->pad, &fmt->format, fmt->which);
	*format = fmt->format;

	/* Propagate the format from sink to source */
	if (fmt->pad == MSM_CSID_PAD_SINK) {
		format = __csid_get_format(csid, cfg, MSM_CSID_PAD_SRC,
					   fmt->which);

		*format = fmt->format;
		csid_try_format(csid, cfg, MSM_CSID_PAD_SRC, format,
				fmt->which);
	}

	return 0;
}

/*
 * csid_init_formats - Initialize formats on all pads
 * @sd: CSID V4L2 subdevice
 * @fh: V4L2 subdev file handle
 *
 * Initialize all pad formats with default values.
 *
 * Return 0 on success or a negative error code otherwise
 */
static int csid_init_formats(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
	struct v4l2_subdev_format format = {
		.pad = MSM_CSID_PAD_SINK,
		.which = fh ? V4L2_SUBDEV_FORMAT_TRY :
			      V4L2_SUBDEV_FORMAT_ACTIVE,
		.format = {
			.code = MEDIA_BUS_FMT_UYVY8_2X8,
			.width = 1920,
			.height = 1080
		}
	};

	return csid_set_format(sd, fh ? fh->pad : NULL, &format);
}

/*
 * csid_set_test_pattern - Set test generator's pattern mode
 * @csid: CSID device
 * @value: desired test pattern mode
 *
 * Return 0 on success or a negative error code otherwise
 */
static int csid_set_test_pattern(struct csid_device *csid, s32 value)
{
	struct csid_testgen_config *tg = &csid->testgen;

	/* If CSID is linked to CSIPHY, do not allow to enable test generator */
	if (value && media_entity_remote_pad(&csid->pads[MSM_CSID_PAD_SINK]))
		return -EBUSY;

	tg->enabled = !!value;

	return csid->ops->configure_testgen_pattern(csid, value);
}

/*
 * csid_s_ctrl - Handle set control subdev method
 * @ctrl: pointer to v4l2 control structure
 *
 * Return 0 on success or a negative error code otherwise
 */
static int csid_s_ctrl(struct v4l2_ctrl *ctrl)
{
	struct csid_device *csid = container_of(ctrl->handler,
						struct csid_device, ctrls);
	int ret = -EINVAL;

	switch (ctrl->id) {
	case V4L2_CID_TEST_PATTERN:
		ret = csid_set_test_pattern(csid, ctrl->val);
		break;
	}

	return ret;
}

static const struct v4l2_ctrl_ops csid_ctrl_ops = {
	.s_ctrl = csid_s_ctrl,
};

/*
 * msm_csid_subdev_init - Initialize CSID device structure and resources
 * @csid: CSID device
 * @res: CSID module resources table
 * @id: CSID module id
 *
 * Return 0 on success or a negative error code otherwise
 */
int msm_csid_subdev_init(struct camss *camss, struct csid_device *csid,
			 const struct resources *res, u8 id)
{
	struct device *dev = camss->dev;
	struct platform_device *pdev = to_platform_device(dev);
	struct resource *r;
	int i, j;
	int ret;

	csid->camss = camss;
	csid->id = id;

	if (camss->version == CAMSS_8x16) {
		csid->ops = &csid_ops_4_1;
	} else if (camss->version == CAMSS_8x96 ||
		   camss->version == CAMSS_660) {
		csid->ops = &csid_ops_4_7;
	} else if (camss->version == CAMSS_845) {
		csid->ops = &csid_ops_170;
	} else {
		return -EINVAL;
	}
	csid->ops->subdev_init(csid);

	/* Memory */

	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, res->reg[0]);
	csid->base = devm_ioremap_resource(dev, r);
	if (IS_ERR(csid->base))
		return PTR_ERR(csid->base);

	/* Interrupt */

	r = platform_get_resource_byname(pdev, IORESOURCE_IRQ,
					 res->interrupt[0]);
	if (!r) {
		dev_err(dev, "missing IRQ\n");
		return -EINVAL;
	}

	csid->irq = r->start;
	snprintf(csid->irq_name, sizeof(csid->irq_name), "%s_%s%d",
		 dev_name(dev), MSM_CSID_NAME, csid->id);
	ret = devm_request_irq(dev, csid->irq, csid->ops->isr,
			       IRQF_TRIGGER_RISING, csid->irq_name, csid);
	if (ret < 0) {
		dev_err(dev, "request_irq failed: %d\n", ret);
		return ret;
	}

	disable_irq(csid->irq);

	/* Clocks */

	csid->nclocks = 0;
	while (res->clock[csid->nclocks])
		csid->nclocks++;

	csid->clock = devm_kcalloc(dev, csid->nclocks, sizeof(*csid->clock),
				    GFP_KERNEL);
	if (!csid->clock)
		return -ENOMEM;

	for (i = 0; i < csid->nclocks; i++) {
		struct camss_clock *clock = &csid->clock[i];

		clock->clk = devm_clk_get(dev, res->clock[i]);
		if (IS_ERR(clock->clk))
			return PTR_ERR(clock->clk);

		clock->name = res->clock[i];

		clock->nfreqs = 0;
		while (res->clock_rate[i][clock->nfreqs])
			clock->nfreqs++;

		if (!clock->nfreqs) {
			clock->freq = NULL;
			continue;
		}

		clock->freq = devm_kcalloc(dev,
					   clock->nfreqs,
					   sizeof(*clock->freq),
					   GFP_KERNEL);
		if (!clock->freq)
			return -ENOMEM;

		for (j = 0; j < clock->nfreqs; j++)
			clock->freq[j] = res->clock_rate[i][j];
	}

	/* Regulator */

	csid->vdda = devm_regulator_get(dev, res->regulator[0]);
	if (IS_ERR(csid->vdda)) {
		dev_err(dev, "could not get regulator\n");
		return PTR_ERR(csid->vdda);
	}

	init_completion(&csid->reset_complete);

	return 0;
}

/*
 * msm_csid_get_csid_id - Get CSID HW module id
 * @entity: Pointer to CSID media entity structure
 * @id: Return CSID HW module id here
 */
void msm_csid_get_csid_id(struct media_entity *entity, u8 *id)
{
	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
	struct csid_device *csid = v4l2_get_subdevdata(sd);

	*id = csid->id;
}

/*
 * csid_get_lane_assign - Calculate CSI2 lane assign configuration parameter
 * @lane_cfg - CSI2 lane configuration
 *
 * Return lane assign
 */
static u32 csid_get_lane_assign(struct csiphy_lanes_cfg *lane_cfg)
{
	u32 lane_assign = 0;
	int i;

	for (i = 0; i < lane_cfg->num_data; i++)
		lane_assign |= lane_cfg->data[i].pos << (i * 4);

	return lane_assign;
}

/*
 * csid_link_setup - Setup CSID connections
 * @entity: Pointer to media entity structure
 * @local: Pointer to local pad
 * @remote: Pointer to remote pad
 * @flags: Link flags
 *
 * Return 0 on success
 */
static int csid_link_setup(struct media_entity *entity,
			   const struct media_pad *local,
			   const struct media_pad *remote, u32 flags)
{
	if (flags & MEDIA_LNK_FL_ENABLED)
		if (media_entity_remote_pad(local))
			return -EBUSY;

	if ((local->flags & MEDIA_PAD_FL_SINK) &&
	    (flags & MEDIA_LNK_FL_ENABLED)) {
		struct v4l2_subdev *sd;
		struct csid_device *csid;
		struct csiphy_device *csiphy;
		struct csiphy_lanes_cfg *lane_cfg;
		struct v4l2_subdev_format format = { 0 };

		sd = media_entity_to_v4l2_subdev(entity);
		csid = v4l2_get_subdevdata(sd);

		/* If test generator is enabled */
		/* do not allow a link from CSIPHY to CSID */
		if (csid->testgen_mode->cur.val != 0)
			return -EBUSY;

		sd = media_entity_to_v4l2_subdev(remote->entity);
		csiphy = v4l2_get_subdevdata(sd);

		/* If a sensor is not linked to CSIPHY */
		/* do no allow a link from CSIPHY to CSID */
		if (!csiphy->cfg.csi2)
			return -EPERM;

		csid->phy.csiphy_id = csiphy->id;

		lane_cfg = &csiphy->cfg.csi2->lane_cfg;
		csid->phy.lane_cnt = lane_cfg->num_data;
		csid->phy.lane_assign = csid_get_lane_assign(lane_cfg);

		/* Reset format on source pad to sink pad format */
		format.pad = MSM_CSID_PAD_SRC;
		format.which = V4L2_SUBDEV_FORMAT_ACTIVE;
		csid_set_format(&csid->subdev, NULL, &format);
	}

	return 0;
}

static const struct v4l2_subdev_core_ops csid_core_ops = {
	.s_power = csid_set_power,
	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
};

static const struct v4l2_subdev_video_ops csid_video_ops = {
	.s_stream = csid_set_stream,
};

static const struct v4l2_subdev_pad_ops csid_pad_ops = {
	.enum_mbus_code = csid_enum_mbus_code,
	.enum_frame_size = csid_enum_frame_size,
	.get_fmt = csid_get_format,
	.set_fmt = csid_set_format,
};

static const struct v4l2_subdev_ops csid_v4l2_ops = {
	.core = &csid_core_ops,
	.video = &csid_video_ops,
	.pad = &csid_pad_ops,
};

static const struct v4l2_subdev_internal_ops csid_v4l2_internal_ops = {
	.open = csid_init_formats,
};

static const struct media_entity_operations csid_media_ops = {
	.link_setup = csid_link_setup,
	.link_validate = v4l2_subdev_link_validate,
};

/*
 * msm_csid_register_entity - Register subdev node for CSID module
 * @csid: CSID device
 * @v4l2_dev: V4L2 device
 *
 * Return 0 on success or a negative error code otherwise
 */
int msm_csid_register_entity(struct csid_device *csid,
			     struct v4l2_device *v4l2_dev)
{
	struct v4l2_subdev *sd = &csid->subdev;
	struct media_pad *pads = csid->pads;
	struct device *dev = csid->camss->dev;
	int ret;

	v4l2_subdev_init(sd, &csid_v4l2_ops);
	sd->internal_ops = &csid_v4l2_internal_ops;
	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
		     V4L2_SUBDEV_FL_HAS_EVENTS;
	snprintf(sd->name, ARRAY_SIZE(sd->name), "%s%d",
		 MSM_CSID_NAME, csid->id);
	v4l2_set_subdevdata(sd, csid);

	ret = v4l2_ctrl_handler_init(&csid->ctrls, 1);
	if (ret < 0) {
		dev_err(dev, "Failed to init ctrl handler: %d\n", ret);
		return ret;
	}

	csid->testgen_mode = v4l2_ctrl_new_std_menu_items(&csid->ctrls,
				&csid_ctrl_ops, V4L2_CID_TEST_PATTERN,
				csid->testgen.nmodes, 0, 0,
				csid->testgen.modes);

	if (csid->ctrls.error) {
		dev_err(dev, "Failed to init ctrl: %d\n", csid->ctrls.error);
		ret = csid->ctrls.error;
		goto free_ctrl;
	}

	csid->subdev.ctrl_handler = &csid->ctrls;

	ret = csid_init_formats(sd, NULL);
	if (ret < 0) {
		dev_err(dev, "Failed to init format: %d\n", ret);
		goto free_ctrl;
	}

	pads[MSM_CSID_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
	pads[MSM_CSID_PAD_SRC].flags = MEDIA_PAD_FL_SOURCE;

	sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
	sd->entity.ops = &csid_media_ops;
	ret = media_entity_pads_init(&sd->entity, MSM_CSID_PADS_NUM, pads);
	if (ret < 0) {
		dev_err(dev, "Failed to init media entity: %d\n", ret);
		goto free_ctrl;
	}

	ret = v4l2_device_register_subdev(v4l2_dev, sd);
	if (ret < 0) {
		dev_err(dev, "Failed to register subdev: %d\n", ret);
		goto media_cleanup;
	}

	return 0;

media_cleanup:
	media_entity_cleanup(&sd->entity);
free_ctrl:
	v4l2_ctrl_handler_free(&csid->ctrls);

	return ret;
}

/*
 * msm_csid_unregister_entity - Unregister CSID module subdev node
 * @csid: CSID device
 */
void msm_csid_unregister_entity(struct csid_device *csid)
{
	v4l2_device_unregister_subdev(&csid->subdev);
	media_entity_cleanup(&csid->subdev.entity);
	v4l2_ctrl_handler_free(&csid->ctrls);
}