xref: /linux/drivers/media/pci/intel/ivsc/mei_csi.c (revision 08df80a3c51674ab73ae770885a383ca553fbbbf)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2023 Intel Corporation. All rights reserved.
4  * Intel Visual Sensing Controller CSI Linux driver
5  */
6 
7 /*
8  * To set ownership of CSI-2 link and to configure CSI-2 link, there
9  * are specific commands, which are sent via MEI protocol. The send
10  * command function uses "completion" as a synchronization mechanism.
11  * The response for command is received via a mei callback which wakes
12  * up the caller. There can be only one outstanding command at a time.
13  */
14 
15 #include <linux/completion.h>
16 #include <linux/delay.h>
17 #include <linux/kernel.h>
18 #include <linux/math64.h>
19 #include <linux/mei_cl_bus.h>
20 #include <linux/module.h>
21 #include <linux/mutex.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/slab.h>
24 #include <linux/units.h>
25 #include <linux/uuid.h>
26 #include <linux/workqueue.h>
27 
28 #include <media/v4l2-async.h>
29 #include <media/v4l2-ctrls.h>
30 #include <media/v4l2-fwnode.h>
31 #include <media/v4l2-subdev.h>
32 
33 #define MEI_CSI_ENTITY_NAME "Intel IVSC CSI"
34 
35 #define MEI_CSI_LINK_FREQ_400MHZ 400000000ULL
36 
37 /* the 5s used here is based on experiment */
38 #define CSI_CMD_TIMEOUT (5 * HZ)
39 /* to setup CSI-2 link an extra delay needed and determined experimentally */
40 #define CSI_FW_READY_DELAY_MS 100
41 /* link frequency unit is 100kHz */
42 #define CSI_LINK_FREQ(x) ((u32)(div_u64(x, 100 * HZ_PER_KHZ)))
43 
44 /*
45  * identify the command id supported by firmware
46  * IPC, as well as the privacy notification id
47  * used when processing privacy event.
48  */
49 enum csi_cmd_id {
50 	/* used to set csi ownership */
51 	CSI_SET_OWNER = 0,
52 
53 	/* used to configure CSI-2 link */
54 	CSI_SET_CONF = 2,
55 
56 	/* privacy notification id used when privacy state changes */
57 	CSI_PRIVACY_NOTIF = 6,
58 };
59 
60 /* CSI-2 link ownership definition */
61 enum csi_link_owner {
62 	CSI_LINK_IVSC,
63 	CSI_LINK_HOST,
64 };
65 
66 /* privacy status definition */
67 enum ivsc_privacy_status {
68 	CSI_PRIVACY_OFF,
69 	CSI_PRIVACY_ON,
70 	CSI_PRIVACY_MAX,
71 };
72 
73 enum csi_pads {
74 	CSI_PAD_SOURCE,
75 	CSI_PAD_SINK,
76 	CSI_NUM_PADS
77 };
78 
79 /* configuration of the CSI-2 link between host and IVSC */
80 struct csi_link_cfg {
81 	/* number of data lanes used on the CSI-2 link */
82 	u32 nr_of_lanes;
83 
84 	/* frequency of the CSI-2 link */
85 	u32 link_freq;
86 
87 	/* for future use */
88 	u32 rsvd[2];
89 } __packed;
90 
91 /* CSI command structure */
92 struct csi_cmd {
93 	u32 cmd_id;
94 	union _cmd_param {
95 		u32 param;
96 		struct csi_link_cfg conf;
97 	} param;
98 } __packed;
99 
100 /* CSI notification structure */
101 struct csi_notif {
102 	u32 cmd_id;
103 	int status;
104 	union _resp_cont {
105 		u32 cont;
106 		struct csi_link_cfg conf;
107 	} cont;
108 } __packed;
109 
110 struct mei_csi {
111 	struct mei_cl_device *cldev;
112 
113 	/* command response */
114 	struct csi_notif cmd_response;
115 	/* used to wait for command response from firmware */
116 	struct completion cmd_completion;
117 	/* protect command download */
118 	struct mutex lock;
119 
120 	struct v4l2_subdev subdev;
121 	struct v4l2_subdev *remote;
122 	struct v4l2_async_notifier notifier;
123 	struct v4l2_ctrl_handler ctrl_handler;
124 	struct v4l2_ctrl *freq_ctrl;
125 	struct v4l2_ctrl *privacy_ctrl;
126 	unsigned int remote_pad;
127 	/* start streaming or not */
128 	int streaming;
129 
130 	struct media_pad pads[CSI_NUM_PADS];
131 	struct v4l2_mbus_framefmt format_mbus[CSI_NUM_PADS];
132 
133 	/* number of data lanes used on the CSI-2 link */
134 	u32 nr_of_lanes;
135 	/* frequency of the CSI-2 link */
136 	u64 link_freq;
137 
138 	/* privacy status */
139 	enum ivsc_privacy_status status;
140 };
141 
142 static const struct v4l2_mbus_framefmt mei_csi_format_mbus_default = {
143 	.width = 1,
144 	.height = 1,
145 	.code = MEDIA_BUS_FMT_Y8_1X8,
146 	.field = V4L2_FIELD_NONE,
147 };
148 
149 static s64 link_freq_menu_items[] = {
150 	MEI_CSI_LINK_FREQ_400MHZ
151 };
152 
153 static inline struct mei_csi *notifier_to_csi(struct v4l2_async_notifier *n)
154 {
155 	return container_of(n, struct mei_csi, notifier);
156 }
157 
158 static inline struct mei_csi *sd_to_csi(struct v4l2_subdev *sd)
159 {
160 	return container_of(sd, struct mei_csi, subdev);
161 }
162 
163 static inline struct mei_csi *ctrl_to_csi(struct v4l2_ctrl *ctrl)
164 {
165 	return container_of(ctrl->handler, struct mei_csi, ctrl_handler);
166 }
167 
168 /* send a command to firmware and mutex must be held by caller */
169 static int mei_csi_send(struct mei_csi *csi, u8 *buf, size_t len)
170 {
171 	struct csi_cmd *cmd = (struct csi_cmd *)buf;
172 	int ret;
173 
174 	reinit_completion(&csi->cmd_completion);
175 
176 	ret = mei_cldev_send(csi->cldev, buf, len);
177 	if (ret < 0)
178 		goto out;
179 
180 	ret = wait_for_completion_killable_timeout(&csi->cmd_completion,
181 						   CSI_CMD_TIMEOUT);
182 	if (ret < 0) {
183 		goto out;
184 	} else if (!ret) {
185 		ret = -ETIMEDOUT;
186 		goto out;
187 	}
188 
189 	/* command response status */
190 	ret = csi->cmd_response.status;
191 	if (ret) {
192 		ret = -EINVAL;
193 		goto out;
194 	}
195 
196 	if (csi->cmd_response.cmd_id != cmd->cmd_id)
197 		ret = -EINVAL;
198 
199 out:
200 	return ret;
201 }
202 
203 /* set CSI-2 link ownership */
204 static int csi_set_link_owner(struct mei_csi *csi, enum csi_link_owner owner)
205 {
206 	struct csi_cmd cmd = { 0 };
207 	size_t cmd_size;
208 	int ret;
209 
210 	cmd.cmd_id = CSI_SET_OWNER;
211 	cmd.param.param = owner;
212 	cmd_size = sizeof(cmd.cmd_id) + sizeof(cmd.param.param);
213 
214 	mutex_lock(&csi->lock);
215 
216 	ret = mei_csi_send(csi, (u8 *)&cmd, cmd_size);
217 
218 	mutex_unlock(&csi->lock);
219 
220 	return ret;
221 }
222 
223 /* configure CSI-2 link between host and IVSC */
224 static int csi_set_link_cfg(struct mei_csi *csi)
225 {
226 	struct csi_cmd cmd = { 0 };
227 	size_t cmd_size;
228 	int ret;
229 
230 	cmd.cmd_id = CSI_SET_CONF;
231 	cmd.param.conf.nr_of_lanes = csi->nr_of_lanes;
232 	cmd.param.conf.link_freq = CSI_LINK_FREQ(csi->link_freq);
233 	cmd_size = sizeof(cmd.cmd_id) + sizeof(cmd.param.conf);
234 
235 	mutex_lock(&csi->lock);
236 
237 	ret = mei_csi_send(csi, (u8 *)&cmd, cmd_size);
238 	/*
239 	 * wait configuration ready if download success. placing
240 	 * delay under mutex is to make sure current command flow
241 	 * completed before starting a possible new one.
242 	 */
243 	if (!ret)
244 		msleep(CSI_FW_READY_DELAY_MS);
245 
246 	mutex_unlock(&csi->lock);
247 
248 	return ret;
249 }
250 
251 /* callback for receive */
252 static void mei_csi_rx(struct mei_cl_device *cldev)
253 {
254 	struct mei_csi *csi = mei_cldev_get_drvdata(cldev);
255 	struct csi_notif notif = { 0 };
256 	int ret;
257 
258 	ret = mei_cldev_recv(cldev, (u8 *)&notif, sizeof(notif));
259 	if (ret < 0) {
260 		dev_err(&cldev->dev, "recv error: %d\n", ret);
261 		return;
262 	}
263 
264 	switch (notif.cmd_id) {
265 	case CSI_PRIVACY_NOTIF:
266 		if (notif.cont.cont < CSI_PRIVACY_MAX) {
267 			csi->status = notif.cont.cont;
268 			v4l2_ctrl_s_ctrl(csi->privacy_ctrl, csi->status);
269 		}
270 		break;
271 	case CSI_SET_OWNER:
272 	case CSI_SET_CONF:
273 		memcpy(&csi->cmd_response, &notif, ret);
274 
275 		complete(&csi->cmd_completion);
276 		break;
277 	default:
278 		break;
279 	}
280 }
281 
282 static int mei_csi_set_stream(struct v4l2_subdev *sd, int enable)
283 {
284 	struct mei_csi *csi = sd_to_csi(sd);
285 	s64 freq;
286 	int ret;
287 
288 	if (enable && csi->streaming == 0) {
289 		freq = v4l2_get_link_freq(csi->remote->ctrl_handler, 0, 0);
290 		if (freq < 0) {
291 			dev_err(&csi->cldev->dev,
292 				"error %lld, invalid link_freq\n", freq);
293 			ret = freq;
294 			goto err;
295 		}
296 		csi->link_freq = freq;
297 
298 		/* switch CSI-2 link to host */
299 		ret = csi_set_link_owner(csi, CSI_LINK_HOST);
300 		if (ret < 0)
301 			goto err;
302 
303 		/* configure CSI-2 link */
304 		ret = csi_set_link_cfg(csi);
305 		if (ret < 0)
306 			goto err_switch;
307 
308 		ret = v4l2_subdev_call(csi->remote, video, s_stream, 1);
309 		if (ret)
310 			goto err_switch;
311 	} else if (!enable && csi->streaming == 1) {
312 		v4l2_subdev_call(csi->remote, video, s_stream, 0);
313 
314 		/* switch CSI-2 link to IVSC */
315 		ret = csi_set_link_owner(csi, CSI_LINK_IVSC);
316 		if (ret < 0)
317 			dev_warn(&csi->cldev->dev,
318 				 "failed to switch CSI2 link: %d\n", ret);
319 	}
320 
321 	csi->streaming = enable;
322 
323 	return 0;
324 
325 err_switch:
326 	csi_set_link_owner(csi, CSI_LINK_IVSC);
327 
328 err:
329 	return ret;
330 }
331 
332 static struct v4l2_mbus_framefmt *
333 mei_csi_get_pad_format(struct v4l2_subdev *sd,
334 		       struct v4l2_subdev_state *sd_state,
335 		       unsigned int pad, u32 which)
336 {
337 	struct mei_csi *csi = sd_to_csi(sd);
338 
339 	switch (which) {
340 	case V4L2_SUBDEV_FORMAT_TRY:
341 		return v4l2_subdev_state_get_format(sd_state, pad);
342 	case V4L2_SUBDEV_FORMAT_ACTIVE:
343 		return &csi->format_mbus[pad];
344 	default:
345 		return NULL;
346 	}
347 }
348 
349 static int mei_csi_init_state(struct v4l2_subdev *sd,
350 			      struct v4l2_subdev_state *sd_state)
351 {
352 	struct v4l2_mbus_framefmt *mbusformat;
353 	struct mei_csi *csi = sd_to_csi(sd);
354 	unsigned int i;
355 
356 	mutex_lock(&csi->lock);
357 
358 	for (i = 0; i < sd->entity.num_pads; i++) {
359 		mbusformat = v4l2_subdev_state_get_format(sd_state, i);
360 		*mbusformat = mei_csi_format_mbus_default;
361 	}
362 
363 	mutex_unlock(&csi->lock);
364 
365 	return 0;
366 }
367 
368 static int mei_csi_get_fmt(struct v4l2_subdev *sd,
369 			   struct v4l2_subdev_state *sd_state,
370 			   struct v4l2_subdev_format *format)
371 {
372 	struct v4l2_mbus_framefmt *mbusformat;
373 	struct mei_csi *csi = sd_to_csi(sd);
374 
375 	mutex_lock(&csi->lock);
376 
377 	mbusformat = mei_csi_get_pad_format(sd, sd_state, format->pad,
378 					    format->which);
379 	if (mbusformat)
380 		format->format = *mbusformat;
381 
382 	mutex_unlock(&csi->lock);
383 
384 	return 0;
385 }
386 
387 static int mei_csi_set_fmt(struct v4l2_subdev *sd,
388 			   struct v4l2_subdev_state *sd_state,
389 			   struct v4l2_subdev_format *format)
390 {
391 	struct v4l2_mbus_framefmt *source_mbusformat;
392 	struct v4l2_mbus_framefmt *mbusformat;
393 	struct mei_csi *csi = sd_to_csi(sd);
394 	struct media_pad *pad;
395 
396 	mbusformat = mei_csi_get_pad_format(sd, sd_state, format->pad,
397 					    format->which);
398 	if (!mbusformat)
399 		return -EINVAL;
400 
401 	source_mbusformat = mei_csi_get_pad_format(sd, sd_state, CSI_PAD_SOURCE,
402 						   format->which);
403 	if (!source_mbusformat)
404 		return -EINVAL;
405 
406 	v4l_bound_align_image(&format->format.width, 1, 65536, 0,
407 			      &format->format.height, 1, 65536, 0, 0);
408 
409 	switch (format->format.code) {
410 	case MEDIA_BUS_FMT_RGB444_1X12:
411 	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_BE:
412 	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE:
413 	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_BE:
414 	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_LE:
415 	case MEDIA_BUS_FMT_RGB565_1X16:
416 	case MEDIA_BUS_FMT_BGR565_2X8_BE:
417 	case MEDIA_BUS_FMT_BGR565_2X8_LE:
418 	case MEDIA_BUS_FMT_RGB565_2X8_BE:
419 	case MEDIA_BUS_FMT_RGB565_2X8_LE:
420 	case MEDIA_BUS_FMT_RGB666_1X18:
421 	case MEDIA_BUS_FMT_RBG888_1X24:
422 	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
423 	case MEDIA_BUS_FMT_BGR888_1X24:
424 	case MEDIA_BUS_FMT_GBR888_1X24:
425 	case MEDIA_BUS_FMT_RGB888_1X24:
426 	case MEDIA_BUS_FMT_RGB888_2X12_BE:
427 	case MEDIA_BUS_FMT_RGB888_2X12_LE:
428 	case MEDIA_BUS_FMT_ARGB8888_1X32:
429 	case MEDIA_BUS_FMT_RGB888_1X32_PADHI:
430 	case MEDIA_BUS_FMT_RGB101010_1X30:
431 	case MEDIA_BUS_FMT_RGB121212_1X36:
432 	case MEDIA_BUS_FMT_RGB161616_1X48:
433 	case MEDIA_BUS_FMT_Y8_1X8:
434 	case MEDIA_BUS_FMT_UV8_1X8:
435 	case MEDIA_BUS_FMT_UYVY8_1_5X8:
436 	case MEDIA_BUS_FMT_VYUY8_1_5X8:
437 	case MEDIA_BUS_FMT_YUYV8_1_5X8:
438 	case MEDIA_BUS_FMT_YVYU8_1_5X8:
439 	case MEDIA_BUS_FMT_UYVY8_2X8:
440 	case MEDIA_BUS_FMT_VYUY8_2X8:
441 	case MEDIA_BUS_FMT_YUYV8_2X8:
442 	case MEDIA_BUS_FMT_YVYU8_2X8:
443 	case MEDIA_BUS_FMT_Y10_1X10:
444 	case MEDIA_BUS_FMT_UYVY10_2X10:
445 	case MEDIA_BUS_FMT_VYUY10_2X10:
446 	case MEDIA_BUS_FMT_YUYV10_2X10:
447 	case MEDIA_BUS_FMT_YVYU10_2X10:
448 	case MEDIA_BUS_FMT_Y12_1X12:
449 	case MEDIA_BUS_FMT_UYVY12_2X12:
450 	case MEDIA_BUS_FMT_VYUY12_2X12:
451 	case MEDIA_BUS_FMT_YUYV12_2X12:
452 	case MEDIA_BUS_FMT_YVYU12_2X12:
453 	case MEDIA_BUS_FMT_UYVY8_1X16:
454 	case MEDIA_BUS_FMT_VYUY8_1X16:
455 	case MEDIA_BUS_FMT_YUYV8_1X16:
456 	case MEDIA_BUS_FMT_YVYU8_1X16:
457 	case MEDIA_BUS_FMT_YDYUYDYV8_1X16:
458 	case MEDIA_BUS_FMT_UYVY10_1X20:
459 	case MEDIA_BUS_FMT_VYUY10_1X20:
460 	case MEDIA_BUS_FMT_YUYV10_1X20:
461 	case MEDIA_BUS_FMT_YVYU10_1X20:
462 	case MEDIA_BUS_FMT_VUY8_1X24:
463 	case MEDIA_BUS_FMT_YUV8_1X24:
464 	case MEDIA_BUS_FMT_UYYVYY8_0_5X24:
465 	case MEDIA_BUS_FMT_UYVY12_1X24:
466 	case MEDIA_BUS_FMT_VYUY12_1X24:
467 	case MEDIA_BUS_FMT_YUYV12_1X24:
468 	case MEDIA_BUS_FMT_YVYU12_1X24:
469 	case MEDIA_BUS_FMT_YUV10_1X30:
470 	case MEDIA_BUS_FMT_UYYVYY10_0_5X30:
471 	case MEDIA_BUS_FMT_AYUV8_1X32:
472 	case MEDIA_BUS_FMT_UYYVYY12_0_5X36:
473 	case MEDIA_BUS_FMT_YUV12_1X36:
474 	case MEDIA_BUS_FMT_YUV16_1X48:
475 	case MEDIA_BUS_FMT_UYYVYY16_0_5X48:
476 	case MEDIA_BUS_FMT_JPEG_1X8:
477 	case MEDIA_BUS_FMT_AHSV8888_1X32:
478 	case MEDIA_BUS_FMT_SBGGR8_1X8:
479 	case MEDIA_BUS_FMT_SGBRG8_1X8:
480 	case MEDIA_BUS_FMT_SGRBG8_1X8:
481 	case MEDIA_BUS_FMT_SRGGB8_1X8:
482 	case MEDIA_BUS_FMT_SBGGR10_1X10:
483 	case MEDIA_BUS_FMT_SGBRG10_1X10:
484 	case MEDIA_BUS_FMT_SGRBG10_1X10:
485 	case MEDIA_BUS_FMT_SRGGB10_1X10:
486 	case MEDIA_BUS_FMT_SBGGR12_1X12:
487 	case MEDIA_BUS_FMT_SGBRG12_1X12:
488 	case MEDIA_BUS_FMT_SGRBG12_1X12:
489 	case MEDIA_BUS_FMT_SRGGB12_1X12:
490 	case MEDIA_BUS_FMT_SBGGR14_1X14:
491 	case MEDIA_BUS_FMT_SGBRG14_1X14:
492 	case MEDIA_BUS_FMT_SGRBG14_1X14:
493 	case MEDIA_BUS_FMT_SRGGB14_1X14:
494 	case MEDIA_BUS_FMT_SBGGR16_1X16:
495 	case MEDIA_BUS_FMT_SGBRG16_1X16:
496 	case MEDIA_BUS_FMT_SGRBG16_1X16:
497 	case MEDIA_BUS_FMT_SRGGB16_1X16:
498 		break;
499 	default:
500 		format->format.code = MEDIA_BUS_FMT_Y8_1X8;
501 		break;
502 	}
503 
504 	if (format->format.field == V4L2_FIELD_ANY)
505 		format->format.field = V4L2_FIELD_NONE;
506 
507 	mutex_lock(&csi->lock);
508 
509 	pad = &csi->pads[format->pad];
510 	if (pad->flags & MEDIA_PAD_FL_SOURCE)
511 		format->format = csi->format_mbus[CSI_PAD_SINK];
512 
513 	*mbusformat = format->format;
514 
515 	if (pad->flags & MEDIA_PAD_FL_SINK)
516 		*source_mbusformat = format->format;
517 
518 	mutex_unlock(&csi->lock);
519 
520 	return 0;
521 }
522 
523 static int mei_csi_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
524 {
525 	struct mei_csi *csi = ctrl_to_csi(ctrl);
526 	s64 freq;
527 
528 	if (ctrl->id == V4L2_CID_LINK_FREQ) {
529 		if (!csi->remote)
530 			return -EINVAL;
531 
532 		freq = v4l2_get_link_freq(csi->remote->ctrl_handler, 0, 0);
533 		if (freq < 0) {
534 			dev_err(&csi->cldev->dev,
535 				"error %lld, invalid link_freq\n", freq);
536 			return -EINVAL;
537 		}
538 
539 		link_freq_menu_items[0] = freq;
540 		ctrl->val = 0;
541 
542 		return 0;
543 	}
544 
545 	return -EINVAL;
546 }
547 
548 static const struct v4l2_ctrl_ops mei_csi_ctrl_ops = {
549 	.g_volatile_ctrl = mei_csi_g_volatile_ctrl,
550 };
551 
552 static const struct v4l2_subdev_video_ops mei_csi_video_ops = {
553 	.s_stream = mei_csi_set_stream,
554 };
555 
556 static const struct v4l2_subdev_pad_ops mei_csi_pad_ops = {
557 	.get_fmt = mei_csi_get_fmt,
558 	.set_fmt = mei_csi_set_fmt,
559 };
560 
561 static const struct v4l2_subdev_ops mei_csi_subdev_ops = {
562 	.video = &mei_csi_video_ops,
563 	.pad = &mei_csi_pad_ops,
564 };
565 
566 static const struct v4l2_subdev_internal_ops mei_csi_internal_ops = {
567 	.init_state = mei_csi_init_state,
568 };
569 
570 static const struct media_entity_operations mei_csi_entity_ops = {
571 	.link_validate = v4l2_subdev_link_validate,
572 };
573 
574 static int mei_csi_notify_bound(struct v4l2_async_notifier *notifier,
575 				struct v4l2_subdev *subdev,
576 				struct v4l2_async_connection *asd)
577 {
578 	struct mei_csi *csi = notifier_to_csi(notifier);
579 	int pad;
580 
581 	pad = media_entity_get_fwnode_pad(&subdev->entity, asd->match.fwnode,
582 					  MEDIA_PAD_FL_SOURCE);
583 	if (pad < 0)
584 		return pad;
585 
586 	csi->remote = subdev;
587 	csi->remote_pad = pad;
588 
589 	return media_create_pad_link(&subdev->entity, pad,
590 				     &csi->subdev.entity, 1,
591 				     MEDIA_LNK_FL_ENABLED |
592 				     MEDIA_LNK_FL_IMMUTABLE);
593 }
594 
595 static void mei_csi_notify_unbind(struct v4l2_async_notifier *notifier,
596 				  struct v4l2_subdev *subdev,
597 				  struct v4l2_async_connection *asd)
598 {
599 	struct mei_csi *csi = notifier_to_csi(notifier);
600 
601 	csi->remote = NULL;
602 }
603 
604 static const struct v4l2_async_notifier_operations mei_csi_notify_ops = {
605 	.bound = mei_csi_notify_bound,
606 	.unbind = mei_csi_notify_unbind,
607 };
608 
609 static int mei_csi_init_controls(struct mei_csi *csi)
610 {
611 	u32 max;
612 	int ret;
613 
614 	ret = v4l2_ctrl_handler_init(&csi->ctrl_handler, 2);
615 	if (ret)
616 		return ret;
617 
618 	csi->ctrl_handler.lock = &csi->lock;
619 
620 	max = ARRAY_SIZE(link_freq_menu_items) - 1;
621 	csi->freq_ctrl = v4l2_ctrl_new_int_menu(&csi->ctrl_handler,
622 						&mei_csi_ctrl_ops,
623 						V4L2_CID_LINK_FREQ,
624 						max,
625 						0,
626 						link_freq_menu_items);
627 	if (csi->freq_ctrl)
628 		csi->freq_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY |
629 					 V4L2_CTRL_FLAG_VOLATILE;
630 
631 	csi->privacy_ctrl = v4l2_ctrl_new_std(&csi->ctrl_handler, NULL,
632 					      V4L2_CID_PRIVACY, 0, 1, 1, 0);
633 	if (csi->privacy_ctrl)
634 		csi->privacy_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
635 
636 	if (csi->ctrl_handler.error)
637 		return csi->ctrl_handler.error;
638 
639 	csi->subdev.ctrl_handler = &csi->ctrl_handler;
640 
641 	return 0;
642 }
643 
644 static int mei_csi_parse_firmware(struct mei_csi *csi)
645 {
646 	struct v4l2_fwnode_endpoint v4l2_ep = {
647 		.bus_type = V4L2_MBUS_CSI2_DPHY,
648 	};
649 	struct device *dev = &csi->cldev->dev;
650 	struct v4l2_async_connection *asd;
651 	struct fwnode_handle *sink_ep, *source_ep;
652 	int ret;
653 
654 	sink_ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0, 0);
655 	if (!sink_ep) {
656 		dev_err(dev, "can't obtain sink endpoint\n");
657 		return -EINVAL;
658 	}
659 
660 	v4l2_async_subdev_nf_init(&csi->notifier, &csi->subdev);
661 	csi->notifier.ops = &mei_csi_notify_ops;
662 
663 	ret = v4l2_fwnode_endpoint_parse(sink_ep, &v4l2_ep);
664 	if (ret) {
665 		dev_err(dev, "could not parse v4l2 sink endpoint\n");
666 		goto out_nf_cleanup;
667 	}
668 
669 	csi->nr_of_lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
670 
671 	source_ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 1, 0, 0);
672 	if (!source_ep) {
673 		ret = -ENOTCONN;
674 		dev_err(dev, "can't obtain source endpoint\n");
675 		goto out_nf_cleanup;
676 	}
677 
678 	ret = v4l2_fwnode_endpoint_parse(source_ep, &v4l2_ep);
679 	fwnode_handle_put(source_ep);
680 	if (ret) {
681 		dev_err(dev, "could not parse v4l2 source endpoint\n");
682 		goto out_nf_cleanup;
683 	}
684 
685 	if (csi->nr_of_lanes != v4l2_ep.bus.mipi_csi2.num_data_lanes) {
686 		ret = -EINVAL;
687 		dev_err(dev,
688 			"the number of lanes does not match (%u vs. %u)\n",
689 			csi->nr_of_lanes, v4l2_ep.bus.mipi_csi2.num_data_lanes);
690 		goto out_nf_cleanup;
691 	}
692 
693 	asd = v4l2_async_nf_add_fwnode_remote(&csi->notifier, sink_ep,
694 					      struct v4l2_async_connection);
695 	if (IS_ERR(asd)) {
696 		ret = PTR_ERR(asd);
697 		goto out_nf_cleanup;
698 	}
699 
700 	ret = v4l2_async_nf_register(&csi->notifier);
701 	if (ret)
702 		goto out_nf_cleanup;
703 
704 	fwnode_handle_put(sink_ep);
705 
706 	return 0;
707 
708 out_nf_cleanup:
709 	v4l2_async_nf_cleanup(&csi->notifier);
710 	fwnode_handle_put(sink_ep);
711 
712 	return ret;
713 }
714 
715 static int mei_csi_probe(struct mei_cl_device *cldev,
716 			 const struct mei_cl_device_id *id)
717 {
718 	struct device *dev = &cldev->dev;
719 	struct mei_csi *csi;
720 	int ret;
721 
722 	if (!dev_fwnode(dev))
723 		return -EPROBE_DEFER;
724 
725 	csi = devm_kzalloc(dev, sizeof(struct mei_csi), GFP_KERNEL);
726 	if (!csi)
727 		return -ENOMEM;
728 
729 	csi->cldev = cldev;
730 	mutex_init(&csi->lock);
731 	init_completion(&csi->cmd_completion);
732 
733 	mei_cldev_set_drvdata(cldev, csi);
734 
735 	ret = mei_cldev_enable(cldev);
736 	if (ret < 0) {
737 		dev_err(dev, "mei_cldev_enable failed: %d\n", ret);
738 		goto destroy_mutex;
739 	}
740 
741 	ret = mei_cldev_register_rx_cb(cldev, mei_csi_rx);
742 	if (ret) {
743 		dev_err(dev, "event cb registration failed: %d\n", ret);
744 		goto err_disable;
745 	}
746 
747 	ret = mei_csi_parse_firmware(csi);
748 	if (ret)
749 		goto err_disable;
750 
751 	csi->subdev.dev = &cldev->dev;
752 	v4l2_subdev_init(&csi->subdev, &mei_csi_subdev_ops);
753 	csi->subdev.internal_ops = &mei_csi_internal_ops;
754 	v4l2_set_subdevdata(&csi->subdev, csi);
755 	csi->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE |
756 			    V4L2_SUBDEV_FL_HAS_EVENTS;
757 	csi->subdev.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
758 	csi->subdev.entity.ops = &mei_csi_entity_ops;
759 
760 	snprintf(csi->subdev.name, sizeof(csi->subdev.name),
761 		 MEI_CSI_ENTITY_NAME);
762 
763 	ret = mei_csi_init_controls(csi);
764 	if (ret)
765 		goto err_ctrl_handler;
766 
767 	csi->format_mbus[CSI_PAD_SOURCE] = mei_csi_format_mbus_default;
768 	csi->format_mbus[CSI_PAD_SINK] = mei_csi_format_mbus_default;
769 
770 	csi->pads[CSI_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
771 	csi->pads[CSI_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
772 	ret = media_entity_pads_init(&csi->subdev.entity, CSI_NUM_PADS,
773 				     csi->pads);
774 	if (ret)
775 		goto err_ctrl_handler;
776 
777 	ret = v4l2_subdev_init_finalize(&csi->subdev);
778 	if (ret < 0)
779 		goto err_entity;
780 
781 	ret = v4l2_async_register_subdev(&csi->subdev);
782 	if (ret < 0)
783 		goto err_subdev;
784 
785 	pm_runtime_enable(&cldev->dev);
786 
787 	return 0;
788 
789 err_subdev:
790 	v4l2_subdev_cleanup(&csi->subdev);
791 
792 err_entity:
793 	media_entity_cleanup(&csi->subdev.entity);
794 
795 err_ctrl_handler:
796 	v4l2_ctrl_handler_free(&csi->ctrl_handler);
797 	v4l2_async_nf_unregister(&csi->notifier);
798 	v4l2_async_nf_cleanup(&csi->notifier);
799 
800 err_disable:
801 	mei_cldev_disable(cldev);
802 
803 destroy_mutex:
804 	mutex_destroy(&csi->lock);
805 
806 	return ret;
807 }
808 
809 static void mei_csi_remove(struct mei_cl_device *cldev)
810 {
811 	struct mei_csi *csi = mei_cldev_get_drvdata(cldev);
812 
813 	v4l2_async_nf_unregister(&csi->notifier);
814 	v4l2_async_nf_cleanup(&csi->notifier);
815 	v4l2_ctrl_handler_free(&csi->ctrl_handler);
816 	v4l2_async_unregister_subdev(&csi->subdev);
817 	v4l2_subdev_cleanup(&csi->subdev);
818 	media_entity_cleanup(&csi->subdev.entity);
819 
820 	pm_runtime_disable(&cldev->dev);
821 
822 	mutex_destroy(&csi->lock);
823 }
824 
825 #define MEI_CSI_UUID UUID_LE(0x92335FCF, 0x3203, 0x4472, \
826 			     0xAF, 0x93, 0x7b, 0x44, 0x53, 0xAC, 0x29, 0xDA)
827 
828 static const struct mei_cl_device_id mei_csi_tbl[] = {
829 	{ .uuid = MEI_CSI_UUID, .version = MEI_CL_VERSION_ANY },
830 	{ /* sentinel */ }
831 };
832 MODULE_DEVICE_TABLE(mei, mei_csi_tbl);
833 
834 static struct mei_cl_driver mei_csi_driver = {
835 	.id_table = mei_csi_tbl,
836 	.name = KBUILD_MODNAME,
837 
838 	.probe = mei_csi_probe,
839 	.remove = mei_csi_remove,
840 };
841 
842 module_mei_cl_driver(mei_csi_driver);
843 
844 MODULE_AUTHOR("Wentong Wu <wentong.wu@intel.com>");
845 MODULE_AUTHOR("Zhifeng Wang <zhifeng.wang@intel.com>");
846 MODULE_DESCRIPTION("Device driver for IVSC CSI");
847 MODULE_LICENSE("GPL");
848