1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * camss-csid.c
4  *
5  * Qualcomm MSM Camera Subsystem - CSID (CSI Decoder) Module
6  *
7  * Copyright (c) 2011-2015, The Linux Foundation. All rights reserved.
8  * Copyright (C) 2015-2018 Linaro Ltd.
9  */
10 #include <linux/clk.h>
11 #include <linux/completion.h>
12 #include <linux/interrupt.h>
13 #include <linux/io.h>
14 #include <linux/kernel.h>
15 #include <linux/of.h>
16 #include <linux/platform_device.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/regulator/consumer.h>
19 #include <media/media-entity.h>
20 #include <media/v4l2-device.h>
21 #include <media/v4l2-event.h>
22 #include <media/v4l2-subdev.h>
23 
24 #include "camss-csid.h"
25 #include "camss-csid-gen1.h"
26 #include "camss.h"
27 
28 /* offset of CSID registers in VFE region for VFE 480 */
29 #define VFE_480_CSID_OFFSET 0x1200
30 #define VFE_480_LITE_CSID_OFFSET 0x200
31 
32 #define MSM_CSID_NAME "msm_csid"
33 
34 const char * const csid_testgen_modes[] = {
35 	"Disabled",
36 	"Incrementing",
37 	"Alternating 0x55/0xAA",
38 	"All Zeros 0x00",
39 	"All Ones 0xFF",
40 	"Pseudo-random Data",
41 	"User Specified",
42 	"Complex pattern",
43 	"Color box",
44 	"Color bars",
45 	NULL
46 };
47 
48 u32 csid_find_code(u32 *codes, unsigned int ncodes,
49 		   unsigned int match_format_idx, u32 match_code)
50 {
51 	int i;
52 
53 	if (!match_code && (match_format_idx >= ncodes))
54 		return 0;
55 
56 	for (i = 0; i < ncodes; i++)
57 		if (match_code) {
58 			if (codes[i] == match_code)
59 				return match_code;
60 		} else {
61 			if (i == match_format_idx)
62 				return codes[i];
63 		}
64 
65 	return codes[0];
66 }
67 
68 const struct csid_format *csid_get_fmt_entry(const struct csid_format *formats,
69 					     unsigned int nformats,
70 					     u32 code)
71 {
72 	unsigned int i;
73 
74 	for (i = 0; i < nformats; i++)
75 		if (code == formats[i].code)
76 			return &formats[i];
77 
78 	WARN(1, "Unknown format\n");
79 
80 	return &formats[0];
81 }
82 
83 /*
84  * csid_set_clock_rates - Calculate and set clock rates on CSID module
85  * @csiphy: CSID device
86  */
87 static int csid_set_clock_rates(struct csid_device *csid)
88 {
89 	struct device *dev = csid->camss->dev;
90 	const struct csid_format *fmt;
91 	s64 link_freq;
92 	int i, j;
93 	int ret;
94 
95 	fmt = csid_get_fmt_entry(csid->formats, csid->nformats,
96 				 csid->fmt[MSM_CSIPHY_PAD_SINK].code);
97 	link_freq = camss_get_link_freq(&csid->subdev.entity, fmt->bpp,
98 					csid->phy.lane_cnt);
99 	if (link_freq < 0)
100 		link_freq = 0;
101 
102 	for (i = 0; i < csid->nclocks; i++) {
103 		struct camss_clock *clock = &csid->clock[i];
104 
105 		if (!strcmp(clock->name, "csi0") ||
106 		    !strcmp(clock->name, "csi1") ||
107 		    !strcmp(clock->name, "csi2") ||
108 		    !strcmp(clock->name, "csi3")) {
109 			u64 min_rate = link_freq / 4;
110 			long rate;
111 
112 			camss_add_clock_margin(&min_rate);
113 
114 			for (j = 0; j < clock->nfreqs; j++)
115 				if (min_rate < clock->freq[j])
116 					break;
117 
118 			if (j == clock->nfreqs) {
119 				dev_err(dev,
120 					"Pixel clock is too high for CSID\n");
121 				return -EINVAL;
122 			}
123 
124 			/* if sensor pixel clock is not available */
125 			/* set highest possible CSID clock rate */
126 			if (min_rate == 0)
127 				j = clock->nfreqs - 1;
128 
129 			rate = clk_round_rate(clock->clk, clock->freq[j]);
130 			if (rate < 0) {
131 				dev_err(dev, "clk round rate failed: %ld\n",
132 					rate);
133 				return -EINVAL;
134 			}
135 
136 			ret = clk_set_rate(clock->clk, rate);
137 			if (ret < 0) {
138 				dev_err(dev, "clk set rate failed: %d\n", ret);
139 				return ret;
140 			}
141 		} else if (clock->nfreqs) {
142 			clk_set_rate(clock->clk, clock->freq[0]);
143 		}
144 	}
145 
146 	return 0;
147 }
148 
149 /*
150  * csid_set_power - Power on/off CSID module
151  * @sd: CSID V4L2 subdevice
152  * @on: Requested power state
153  *
154  * Return 0 on success or a negative error code otherwise
155  */
156 static int csid_set_power(struct v4l2_subdev *sd, int on)
157 {
158 	struct csid_device *csid = v4l2_get_subdevdata(sd);
159 	struct camss *camss = csid->camss;
160 	struct device *dev = camss->dev;
161 	struct vfe_device *vfe = &camss->vfe[csid->id];
162 	u32 version = camss->version;
163 	int ret = 0;
164 
165 	if (on) {
166 		if (version == CAMSS_8250 || version == CAMSS_845) {
167 			ret = vfe_get(vfe);
168 			if (ret < 0)
169 				return ret;
170 		}
171 
172 		ret = pm_runtime_resume_and_get(dev);
173 		if (ret < 0)
174 			return ret;
175 
176 		ret = regulator_bulk_enable(csid->num_supplies,
177 					    csid->supplies);
178 		if (ret < 0) {
179 			pm_runtime_put_sync(dev);
180 			return ret;
181 		}
182 
183 		ret = csid_set_clock_rates(csid);
184 		if (ret < 0) {
185 			regulator_bulk_disable(csid->num_supplies,
186 					       csid->supplies);
187 			pm_runtime_put_sync(dev);
188 			return ret;
189 		}
190 
191 		ret = camss_enable_clocks(csid->nclocks, csid->clock, dev);
192 		if (ret < 0) {
193 			regulator_bulk_disable(csid->num_supplies,
194 					       csid->supplies);
195 			pm_runtime_put_sync(dev);
196 			return ret;
197 		}
198 
199 		enable_irq(csid->irq);
200 
201 		ret = csid->ops->reset(csid);
202 		if (ret < 0) {
203 			disable_irq(csid->irq);
204 			camss_disable_clocks(csid->nclocks, csid->clock);
205 			regulator_bulk_disable(csid->num_supplies,
206 					       csid->supplies);
207 			pm_runtime_put_sync(dev);
208 			return ret;
209 		}
210 
211 		csid->ops->hw_version(csid);
212 	} else {
213 		disable_irq(csid->irq);
214 		camss_disable_clocks(csid->nclocks, csid->clock);
215 		regulator_bulk_disable(csid->num_supplies,
216 				       csid->supplies);
217 		pm_runtime_put_sync(dev);
218 		if (version == CAMSS_8250 || version == CAMSS_845)
219 			vfe_put(vfe);
220 	}
221 
222 	return ret;
223 }
224 
225 /*
226  * csid_set_stream - Enable/disable streaming on CSID module
227  * @sd: CSID V4L2 subdevice
228  * @enable: Requested streaming state
229  *
230  * Main configuration of CSID module is also done here.
231  *
232  * Return 0 on success or a negative error code otherwise
233  */
234 static int csid_set_stream(struct v4l2_subdev *sd, int enable)
235 {
236 	struct csid_device *csid = v4l2_get_subdevdata(sd);
237 	int ret;
238 
239 	if (enable) {
240 		ret = v4l2_ctrl_handler_setup(&csid->ctrls);
241 		if (ret < 0) {
242 			dev_err(csid->camss->dev,
243 				"could not sync v4l2 controls: %d\n", ret);
244 			return ret;
245 		}
246 
247 		if (!csid->testgen.enabled &&
248 		    !media_entity_remote_pad(&csid->pads[MSM_CSID_PAD_SINK]))
249 			return -ENOLINK;
250 	}
251 
252 	csid->ops->configure_stream(csid, enable);
253 
254 	return 0;
255 }
256 
257 /*
258  * __csid_get_format - Get pointer to format structure
259  * @csid: CSID device
260  * @cfg: V4L2 subdev pad configuration
261  * @pad: pad from which format is requested
262  * @which: TRY or ACTIVE format
263  *
264  * Return pointer to TRY or ACTIVE format structure
265  */
266 static struct v4l2_mbus_framefmt *
267 __csid_get_format(struct csid_device *csid,
268 		  struct v4l2_subdev_state *sd_state,
269 		  unsigned int pad,
270 		  enum v4l2_subdev_format_whence which)
271 {
272 	if (which == V4L2_SUBDEV_FORMAT_TRY)
273 		return v4l2_subdev_get_try_format(&csid->subdev, sd_state,
274 						  pad);
275 
276 	return &csid->fmt[pad];
277 }
278 
279 /*
280  * csid_try_format - Handle try format by pad subdev method
281  * @csid: CSID device
282  * @cfg: V4L2 subdev pad configuration
283  * @pad: pad on which format is requested
284  * @fmt: pointer to v4l2 format structure
285  * @which: wanted subdev format
286  */
287 static void csid_try_format(struct csid_device *csid,
288 			    struct v4l2_subdev_state *sd_state,
289 			    unsigned int pad,
290 			    struct v4l2_mbus_framefmt *fmt,
291 			    enum v4l2_subdev_format_whence which)
292 {
293 	unsigned int i;
294 
295 	switch (pad) {
296 	case MSM_CSID_PAD_SINK:
297 		/* Set format on sink pad */
298 
299 		for (i = 0; i < csid->nformats; i++)
300 			if (fmt->code == csid->formats[i].code)
301 				break;
302 
303 		/* If not found, use UYVY as default */
304 		if (i >= csid->nformats)
305 			fmt->code = MEDIA_BUS_FMT_UYVY8_2X8;
306 
307 		fmt->width = clamp_t(u32, fmt->width, 1, 8191);
308 		fmt->height = clamp_t(u32, fmt->height, 1, 8191);
309 
310 		fmt->field = V4L2_FIELD_NONE;
311 		fmt->colorspace = V4L2_COLORSPACE_SRGB;
312 
313 		break;
314 
315 	case MSM_CSID_PAD_SRC:
316 		if (csid->testgen_mode->cur.val == 0) {
317 			/* Test generator is disabled, */
318 			/* keep pad formats in sync */
319 			u32 code = fmt->code;
320 
321 			*fmt = *__csid_get_format(csid, sd_state,
322 						      MSM_CSID_PAD_SINK, which);
323 			fmt->code = csid->ops->src_pad_code(csid, fmt->code, 0, code);
324 		} else {
325 			/* Test generator is enabled, set format on source */
326 			/* pad to allow test generator usage */
327 
328 			for (i = 0; i < csid->nformats; i++)
329 				if (csid->formats[i].code == fmt->code)
330 					break;
331 
332 			/* If not found, use UYVY as default */
333 			if (i >= csid->nformats)
334 				fmt->code = MEDIA_BUS_FMT_UYVY8_2X8;
335 
336 			fmt->width = clamp_t(u32, fmt->width, 1, 8191);
337 			fmt->height = clamp_t(u32, fmt->height, 1, 8191);
338 
339 			fmt->field = V4L2_FIELD_NONE;
340 		}
341 		break;
342 	}
343 
344 	fmt->colorspace = V4L2_COLORSPACE_SRGB;
345 }
346 
347 /*
348  * csid_enum_mbus_code - Handle pixel format enumeration
349  * @sd: CSID V4L2 subdevice
350  * @cfg: V4L2 subdev pad configuration
351  * @code: pointer to v4l2_subdev_mbus_code_enum structure
352  * return -EINVAL or zero on success
353  */
354 static int csid_enum_mbus_code(struct v4l2_subdev *sd,
355 			       struct v4l2_subdev_state *sd_state,
356 			       struct v4l2_subdev_mbus_code_enum *code)
357 {
358 	struct csid_device *csid = v4l2_get_subdevdata(sd);
359 
360 	if (code->pad == MSM_CSID_PAD_SINK) {
361 		if (code->index >= csid->nformats)
362 			return -EINVAL;
363 
364 		code->code = csid->formats[code->index].code;
365 	} else {
366 		if (csid->testgen_mode->cur.val == 0) {
367 			struct v4l2_mbus_framefmt *sink_fmt;
368 
369 			sink_fmt = __csid_get_format(csid, sd_state,
370 						     MSM_CSID_PAD_SINK,
371 						     code->which);
372 
373 			code->code = csid->ops->src_pad_code(csid, sink_fmt->code,
374 						       code->index, 0);
375 			if (!code->code)
376 				return -EINVAL;
377 		} else {
378 			if (code->index >= csid->nformats)
379 				return -EINVAL;
380 
381 			code->code = csid->formats[code->index].code;
382 		}
383 	}
384 
385 	return 0;
386 }
387 
388 /*
389  * csid_enum_frame_size - Handle frame size enumeration
390  * @sd: CSID V4L2 subdevice
391  * @cfg: V4L2 subdev pad configuration
392  * @fse: pointer to v4l2_subdev_frame_size_enum structure
393  * return -EINVAL or zero on success
394  */
395 static int csid_enum_frame_size(struct v4l2_subdev *sd,
396 				struct v4l2_subdev_state *sd_state,
397 				struct v4l2_subdev_frame_size_enum *fse)
398 {
399 	struct csid_device *csid = v4l2_get_subdevdata(sd);
400 	struct v4l2_mbus_framefmt format;
401 
402 	if (fse->index != 0)
403 		return -EINVAL;
404 
405 	format.code = fse->code;
406 	format.width = 1;
407 	format.height = 1;
408 	csid_try_format(csid, sd_state, fse->pad, &format, fse->which);
409 	fse->min_width = format.width;
410 	fse->min_height = format.height;
411 
412 	if (format.code != fse->code)
413 		return -EINVAL;
414 
415 	format.code = fse->code;
416 	format.width = -1;
417 	format.height = -1;
418 	csid_try_format(csid, sd_state, fse->pad, &format, fse->which);
419 	fse->max_width = format.width;
420 	fse->max_height = format.height;
421 
422 	return 0;
423 }
424 
425 /*
426  * csid_get_format - Handle get format by pads subdev method
427  * @sd: CSID V4L2 subdevice
428  * @cfg: V4L2 subdev pad configuration
429  * @fmt: pointer to v4l2 subdev format structure
430  *
431  * Return -EINVAL or zero on success
432  */
433 static int csid_get_format(struct v4l2_subdev *sd,
434 			   struct v4l2_subdev_state *sd_state,
435 			   struct v4l2_subdev_format *fmt)
436 {
437 	struct csid_device *csid = v4l2_get_subdevdata(sd);
438 	struct v4l2_mbus_framefmt *format;
439 
440 	format = __csid_get_format(csid, sd_state, fmt->pad, fmt->which);
441 	if (format == NULL)
442 		return -EINVAL;
443 
444 	fmt->format = *format;
445 
446 	return 0;
447 }
448 
449 /*
450  * csid_set_format - Handle set format by pads subdev method
451  * @sd: CSID V4L2 subdevice
452  * @cfg: V4L2 subdev pad configuration
453  * @fmt: pointer to v4l2 subdev format structure
454  *
455  * Return -EINVAL or zero on success
456  */
457 static int csid_set_format(struct v4l2_subdev *sd,
458 			   struct v4l2_subdev_state *sd_state,
459 			   struct v4l2_subdev_format *fmt)
460 {
461 	struct csid_device *csid = v4l2_get_subdevdata(sd);
462 	struct v4l2_mbus_framefmt *format;
463 
464 	format = __csid_get_format(csid, sd_state, fmt->pad, fmt->which);
465 	if (format == NULL)
466 		return -EINVAL;
467 
468 	csid_try_format(csid, sd_state, fmt->pad, &fmt->format, fmt->which);
469 	*format = fmt->format;
470 
471 	/* Propagate the format from sink to source */
472 	if (fmt->pad == MSM_CSID_PAD_SINK) {
473 		format = __csid_get_format(csid, sd_state, MSM_CSID_PAD_SRC,
474 					   fmt->which);
475 
476 		*format = fmt->format;
477 		csid_try_format(csid, sd_state, MSM_CSID_PAD_SRC, format,
478 				fmt->which);
479 	}
480 
481 	return 0;
482 }
483 
484 /*
485  * csid_init_formats - Initialize formats on all pads
486  * @sd: CSID V4L2 subdevice
487  * @fh: V4L2 subdev file handle
488  *
489  * Initialize all pad formats with default values.
490  *
491  * Return 0 on success or a negative error code otherwise
492  */
493 static int csid_init_formats(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
494 {
495 	struct v4l2_subdev_format format = {
496 		.pad = MSM_CSID_PAD_SINK,
497 		.which = fh ? V4L2_SUBDEV_FORMAT_TRY :
498 			      V4L2_SUBDEV_FORMAT_ACTIVE,
499 		.format = {
500 			.code = MEDIA_BUS_FMT_UYVY8_2X8,
501 			.width = 1920,
502 			.height = 1080
503 		}
504 	};
505 
506 	return csid_set_format(sd, fh ? fh->state : NULL, &format);
507 }
508 
509 /*
510  * csid_set_test_pattern - Set test generator's pattern mode
511  * @csid: CSID device
512  * @value: desired test pattern mode
513  *
514  * Return 0 on success or a negative error code otherwise
515  */
516 static int csid_set_test_pattern(struct csid_device *csid, s32 value)
517 {
518 	struct csid_testgen_config *tg = &csid->testgen;
519 
520 	/* If CSID is linked to CSIPHY, do not allow to enable test generator */
521 	if (value && media_entity_remote_pad(&csid->pads[MSM_CSID_PAD_SINK]))
522 		return -EBUSY;
523 
524 	tg->enabled = !!value;
525 
526 	return csid->ops->configure_testgen_pattern(csid, value);
527 }
528 
529 /*
530  * csid_s_ctrl - Handle set control subdev method
531  * @ctrl: pointer to v4l2 control structure
532  *
533  * Return 0 on success or a negative error code otherwise
534  */
535 static int csid_s_ctrl(struct v4l2_ctrl *ctrl)
536 {
537 	struct csid_device *csid = container_of(ctrl->handler,
538 						struct csid_device, ctrls);
539 	int ret = -EINVAL;
540 
541 	switch (ctrl->id) {
542 	case V4L2_CID_TEST_PATTERN:
543 		ret = csid_set_test_pattern(csid, ctrl->val);
544 		break;
545 	}
546 
547 	return ret;
548 }
549 
550 static const struct v4l2_ctrl_ops csid_ctrl_ops = {
551 	.s_ctrl = csid_s_ctrl,
552 };
553 
554 /*
555  * msm_csid_subdev_init - Initialize CSID device structure and resources
556  * @csid: CSID device
557  * @res: CSID module resources table
558  * @id: CSID module id
559  *
560  * Return 0 on success or a negative error code otherwise
561  */
562 int msm_csid_subdev_init(struct camss *camss, struct csid_device *csid,
563 			 const struct resources *res, u8 id)
564 {
565 	struct device *dev = camss->dev;
566 	struct platform_device *pdev = to_platform_device(dev);
567 	int i, j;
568 	int ret;
569 
570 	csid->camss = camss;
571 	csid->id = id;
572 
573 	if (camss->version == CAMSS_8x16) {
574 		csid->ops = &csid_ops_4_1;
575 	} else if (camss->version == CAMSS_8x96 ||
576 		   camss->version == CAMSS_660) {
577 		csid->ops = &csid_ops_4_7;
578 	} else if (camss->version == CAMSS_845 ||
579 		   camss->version == CAMSS_8250) {
580 		csid->ops = &csid_ops_gen2;
581 	} else {
582 		return -EINVAL;
583 	}
584 	csid->ops->subdev_init(csid);
585 
586 	/* Memory */
587 
588 	if (camss->version == CAMSS_8250) {
589 		/* for titan 480, CSID registers are inside the VFE region,
590 		 * between the VFE "top" and "bus" registers. this requires
591 		 * VFE to be initialized before CSID
592 		 */
593 		if (id >= 2) /* VFE/CSID lite */
594 			csid->base = camss->vfe[id].base + VFE_480_LITE_CSID_OFFSET;
595 		else
596 			csid->base = camss->vfe[id].base + VFE_480_CSID_OFFSET;
597 	} else {
598 		csid->base = devm_platform_ioremap_resource_byname(pdev, res->reg[0]);
599 		if (IS_ERR(csid->base))
600 			return PTR_ERR(csid->base);
601 	}
602 
603 	/* Interrupt */
604 
605 	ret = platform_get_irq_byname(pdev, res->interrupt[0]);
606 	if (ret < 0)
607 		return ret;
608 
609 	csid->irq = ret;
610 	snprintf(csid->irq_name, sizeof(csid->irq_name), "%s_%s%d",
611 		 dev_name(dev), MSM_CSID_NAME, csid->id);
612 	ret = devm_request_irq(dev, csid->irq, csid->ops->isr,
613 			       IRQF_TRIGGER_RISING | IRQF_NO_AUTOEN,
614 			       csid->irq_name, csid);
615 	if (ret < 0) {
616 		dev_err(dev, "request_irq failed: %d\n", ret);
617 		return ret;
618 	}
619 
620 	/* Clocks */
621 
622 	csid->nclocks = 0;
623 	while (res->clock[csid->nclocks])
624 		csid->nclocks++;
625 
626 	csid->clock = devm_kcalloc(dev, csid->nclocks, sizeof(*csid->clock),
627 				    GFP_KERNEL);
628 	if (!csid->clock)
629 		return -ENOMEM;
630 
631 	for (i = 0; i < csid->nclocks; i++) {
632 		struct camss_clock *clock = &csid->clock[i];
633 
634 		clock->clk = devm_clk_get(dev, res->clock[i]);
635 		if (IS_ERR(clock->clk))
636 			return PTR_ERR(clock->clk);
637 
638 		clock->name = res->clock[i];
639 
640 		clock->nfreqs = 0;
641 		while (res->clock_rate[i][clock->nfreqs])
642 			clock->nfreqs++;
643 
644 		if (!clock->nfreqs) {
645 			clock->freq = NULL;
646 			continue;
647 		}
648 
649 		clock->freq = devm_kcalloc(dev,
650 					   clock->nfreqs,
651 					   sizeof(*clock->freq),
652 					   GFP_KERNEL);
653 		if (!clock->freq)
654 			return -ENOMEM;
655 
656 		for (j = 0; j < clock->nfreqs; j++)
657 			clock->freq[j] = res->clock_rate[i][j];
658 	}
659 
660 	/* Regulator */
661 	for (i = 0; i < ARRAY_SIZE(res->regulators); i++) {
662 		if (res->regulators[i])
663 			csid->num_supplies++;
664 	}
665 
666 	if (csid->num_supplies) {
667 		csid->supplies = devm_kmalloc_array(camss->dev,
668 						    csid->num_supplies,
669 						    sizeof(csid->supplies),
670 						    GFP_KERNEL);
671 		if (!csid->supplies)
672 			return -ENOMEM;
673 	}
674 
675 	for (i = 0; i < csid->num_supplies; i++)
676 		csid->supplies[i].supply = res->regulators[i];
677 
678 	ret = devm_regulator_bulk_get(camss->dev, csid->num_supplies,
679 				      csid->supplies);
680 	if (ret)
681 		return ret;
682 
683 	init_completion(&csid->reset_complete);
684 
685 	return 0;
686 }
687 
688 /*
689  * msm_csid_get_csid_id - Get CSID HW module id
690  * @entity: Pointer to CSID media entity structure
691  * @id: Return CSID HW module id here
692  */
693 void msm_csid_get_csid_id(struct media_entity *entity, u8 *id)
694 {
695 	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
696 	struct csid_device *csid = v4l2_get_subdevdata(sd);
697 
698 	*id = csid->id;
699 }
700 
701 /*
702  * csid_get_lane_assign - Calculate CSI2 lane assign configuration parameter
703  * @lane_cfg - CSI2 lane configuration
704  *
705  * Return lane assign
706  */
707 static u32 csid_get_lane_assign(struct csiphy_lanes_cfg *lane_cfg)
708 {
709 	u32 lane_assign = 0;
710 	int i;
711 
712 	for (i = 0; i < lane_cfg->num_data; i++)
713 		lane_assign |= lane_cfg->data[i].pos << (i * 4);
714 
715 	return lane_assign;
716 }
717 
718 /*
719  * csid_link_setup - Setup CSID connections
720  * @entity: Pointer to media entity structure
721  * @local: Pointer to local pad
722  * @remote: Pointer to remote pad
723  * @flags: Link flags
724  *
725  * Return 0 on success
726  */
727 static int csid_link_setup(struct media_entity *entity,
728 			   const struct media_pad *local,
729 			   const struct media_pad *remote, u32 flags)
730 {
731 	if (flags & MEDIA_LNK_FL_ENABLED)
732 		if (media_entity_remote_pad(local))
733 			return -EBUSY;
734 
735 	if ((local->flags & MEDIA_PAD_FL_SINK) &&
736 	    (flags & MEDIA_LNK_FL_ENABLED)) {
737 		struct v4l2_subdev *sd;
738 		struct csid_device *csid;
739 		struct csiphy_device *csiphy;
740 		struct csiphy_lanes_cfg *lane_cfg;
741 		struct v4l2_subdev_format format = { 0 };
742 
743 		sd = media_entity_to_v4l2_subdev(entity);
744 		csid = v4l2_get_subdevdata(sd);
745 
746 		/* If test generator is enabled */
747 		/* do not allow a link from CSIPHY to CSID */
748 		if (csid->testgen_mode->cur.val != 0)
749 			return -EBUSY;
750 
751 		sd = media_entity_to_v4l2_subdev(remote->entity);
752 		csiphy = v4l2_get_subdevdata(sd);
753 
754 		/* If a sensor is not linked to CSIPHY */
755 		/* do no allow a link from CSIPHY to CSID */
756 		if (!csiphy->cfg.csi2)
757 			return -EPERM;
758 
759 		csid->phy.csiphy_id = csiphy->id;
760 
761 		lane_cfg = &csiphy->cfg.csi2->lane_cfg;
762 		csid->phy.lane_cnt = lane_cfg->num_data;
763 		csid->phy.lane_assign = csid_get_lane_assign(lane_cfg);
764 
765 		/* Reset format on source pad to sink pad format */
766 		format.pad = MSM_CSID_PAD_SRC;
767 		format.which = V4L2_SUBDEV_FORMAT_ACTIVE;
768 		csid_set_format(&csid->subdev, NULL, &format);
769 	}
770 
771 	return 0;
772 }
773 
774 static const struct v4l2_subdev_core_ops csid_core_ops = {
775 	.s_power = csid_set_power,
776 	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
777 	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
778 };
779 
780 static const struct v4l2_subdev_video_ops csid_video_ops = {
781 	.s_stream = csid_set_stream,
782 };
783 
784 static const struct v4l2_subdev_pad_ops csid_pad_ops = {
785 	.enum_mbus_code = csid_enum_mbus_code,
786 	.enum_frame_size = csid_enum_frame_size,
787 	.get_fmt = csid_get_format,
788 	.set_fmt = csid_set_format,
789 };
790 
791 static const struct v4l2_subdev_ops csid_v4l2_ops = {
792 	.core = &csid_core_ops,
793 	.video = &csid_video_ops,
794 	.pad = &csid_pad_ops,
795 };
796 
797 static const struct v4l2_subdev_internal_ops csid_v4l2_internal_ops = {
798 	.open = csid_init_formats,
799 };
800 
801 static const struct media_entity_operations csid_media_ops = {
802 	.link_setup = csid_link_setup,
803 	.link_validate = v4l2_subdev_link_validate,
804 };
805 
806 /*
807  * msm_csid_register_entity - Register subdev node for CSID module
808  * @csid: CSID device
809  * @v4l2_dev: V4L2 device
810  *
811  * Return 0 on success or a negative error code otherwise
812  */
813 int msm_csid_register_entity(struct csid_device *csid,
814 			     struct v4l2_device *v4l2_dev)
815 {
816 	struct v4l2_subdev *sd = &csid->subdev;
817 	struct media_pad *pads = csid->pads;
818 	struct device *dev = csid->camss->dev;
819 	int ret;
820 
821 	v4l2_subdev_init(sd, &csid_v4l2_ops);
822 	sd->internal_ops = &csid_v4l2_internal_ops;
823 	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
824 		     V4L2_SUBDEV_FL_HAS_EVENTS;
825 	snprintf(sd->name, ARRAY_SIZE(sd->name), "%s%d",
826 		 MSM_CSID_NAME, csid->id);
827 	v4l2_set_subdevdata(sd, csid);
828 
829 	ret = v4l2_ctrl_handler_init(&csid->ctrls, 1);
830 	if (ret < 0) {
831 		dev_err(dev, "Failed to init ctrl handler: %d\n", ret);
832 		return ret;
833 	}
834 
835 	csid->testgen_mode = v4l2_ctrl_new_std_menu_items(&csid->ctrls,
836 				&csid_ctrl_ops, V4L2_CID_TEST_PATTERN,
837 				csid->testgen.nmodes, 0, 0,
838 				csid->testgen.modes);
839 
840 	if (csid->ctrls.error) {
841 		dev_err(dev, "Failed to init ctrl: %d\n", csid->ctrls.error);
842 		ret = csid->ctrls.error;
843 		goto free_ctrl;
844 	}
845 
846 	csid->subdev.ctrl_handler = &csid->ctrls;
847 
848 	ret = csid_init_formats(sd, NULL);
849 	if (ret < 0) {
850 		dev_err(dev, "Failed to init format: %d\n", ret);
851 		goto free_ctrl;
852 	}
853 
854 	pads[MSM_CSID_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
855 	pads[MSM_CSID_PAD_SRC].flags = MEDIA_PAD_FL_SOURCE;
856 
857 	sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
858 	sd->entity.ops = &csid_media_ops;
859 	ret = media_entity_pads_init(&sd->entity, MSM_CSID_PADS_NUM, pads);
860 	if (ret < 0) {
861 		dev_err(dev, "Failed to init media entity: %d\n", ret);
862 		goto free_ctrl;
863 	}
864 
865 	ret = v4l2_device_register_subdev(v4l2_dev, sd);
866 	if (ret < 0) {
867 		dev_err(dev, "Failed to register subdev: %d\n", ret);
868 		goto media_cleanup;
869 	}
870 
871 	return 0;
872 
873 media_cleanup:
874 	media_entity_cleanup(&sd->entity);
875 free_ctrl:
876 	v4l2_ctrl_handler_free(&csid->ctrls);
877 
878 	return ret;
879 }
880 
881 /*
882  * msm_csid_unregister_entity - Unregister CSID module subdev node
883  * @csid: CSID device
884  */
885 void msm_csid_unregister_entity(struct csid_device *csid)
886 {
887 	v4l2_device_unregister_subdev(&csid->subdev);
888 	media_entity_cleanup(&csid->subdev.entity);
889 	v4l2_ctrl_handler_free(&csid->ctrls);
890 }
891