xref: /linux/drivers/media/pci/intel/ivsc/mei_csi.c (revision 7255fcc80d4b525cc10cfaaf7f485830d4ed2000)
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_SINK,
75 	CSI_PAD_SOURCE,
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 
132 	/* number of data lanes used on the CSI-2 link */
133 	u32 nr_of_lanes;
134 	/* frequency of the CSI-2 link */
135 	u64 link_freq;
136 
137 	/* privacy status */
138 	enum ivsc_privacy_status status;
139 };
140 
141 static const struct v4l2_mbus_framefmt mei_csi_format_mbus_default = {
142 	.width = 1,
143 	.height = 1,
144 	.code = MEDIA_BUS_FMT_Y8_1X8,
145 	.field = V4L2_FIELD_NONE,
146 };
147 
148 static s64 link_freq_menu_items[] = {
149 	MEI_CSI_LINK_FREQ_400MHZ
150 };
151 
152 static inline struct mei_csi *notifier_to_csi(struct v4l2_async_notifier *n)
153 {
154 	return container_of(n, struct mei_csi, notifier);
155 }
156 
157 static inline struct mei_csi *sd_to_csi(struct v4l2_subdev *sd)
158 {
159 	return container_of(sd, struct mei_csi, subdev);
160 }
161 
162 static inline struct mei_csi *ctrl_to_csi(struct v4l2_ctrl *ctrl)
163 {
164 	return container_of(ctrl->handler, struct mei_csi, ctrl_handler);
165 }
166 
167 /* send a command to firmware and mutex must be held by caller */
168 static int mei_csi_send(struct mei_csi *csi, u8 *buf, size_t len)
169 {
170 	struct csi_cmd *cmd = (struct csi_cmd *)buf;
171 	int ret;
172 
173 	reinit_completion(&csi->cmd_completion);
174 
175 	ret = mei_cldev_send(csi->cldev, buf, len);
176 	if (ret < 0)
177 		goto out;
178 
179 	ret = wait_for_completion_killable_timeout(&csi->cmd_completion,
180 						   CSI_CMD_TIMEOUT);
181 	if (ret < 0) {
182 		goto out;
183 	} else if (!ret) {
184 		ret = -ETIMEDOUT;
185 		goto out;
186 	}
187 
188 	/* command response status */
189 	ret = csi->cmd_response.status;
190 	if (ret) {
191 		ret = -EINVAL;
192 		goto out;
193 	}
194 
195 	if (csi->cmd_response.cmd_id != cmd->cmd_id)
196 		ret = -EINVAL;
197 
198 out:
199 	return ret;
200 }
201 
202 /* set CSI-2 link ownership */
203 static int csi_set_link_owner(struct mei_csi *csi, enum csi_link_owner owner)
204 {
205 	struct csi_cmd cmd = { 0 };
206 	size_t cmd_size;
207 	int ret;
208 
209 	cmd.cmd_id = CSI_SET_OWNER;
210 	cmd.param.param = owner;
211 	cmd_size = sizeof(cmd.cmd_id) + sizeof(cmd.param.param);
212 
213 	mutex_lock(&csi->lock);
214 
215 	ret = mei_csi_send(csi, (u8 *)&cmd, cmd_size);
216 
217 	mutex_unlock(&csi->lock);
218 
219 	return ret;
220 }
221 
222 /* configure CSI-2 link between host and IVSC */
223 static int csi_set_link_cfg(struct mei_csi *csi)
224 {
225 	struct csi_cmd cmd = { 0 };
226 	size_t cmd_size;
227 	int ret;
228 
229 	cmd.cmd_id = CSI_SET_CONF;
230 	cmd.param.conf.nr_of_lanes = csi->nr_of_lanes;
231 	cmd.param.conf.link_freq = CSI_LINK_FREQ(csi->link_freq);
232 	cmd_size = sizeof(cmd.cmd_id) + sizeof(cmd.param.conf);
233 
234 	mutex_lock(&csi->lock);
235 
236 	ret = mei_csi_send(csi, (u8 *)&cmd, cmd_size);
237 	/*
238 	 * wait configuration ready if download success. placing
239 	 * delay under mutex is to make sure current command flow
240 	 * completed before starting a possible new one.
241 	 */
242 	if (!ret)
243 		msleep(CSI_FW_READY_DELAY_MS);
244 
245 	mutex_unlock(&csi->lock);
246 
247 	return ret;
248 }
249 
250 /* callback for receive */
251 static void mei_csi_rx(struct mei_cl_device *cldev)
252 {
253 	struct mei_csi *csi = mei_cldev_get_drvdata(cldev);
254 	struct csi_notif notif = { 0 };
255 	int ret;
256 
257 	ret = mei_cldev_recv(cldev, (u8 *)&notif, sizeof(notif));
258 	if (ret < 0) {
259 		dev_err(&cldev->dev, "recv error: %d\n", ret);
260 		return;
261 	}
262 
263 	switch (notif.cmd_id) {
264 	case CSI_PRIVACY_NOTIF:
265 		if (notif.cont.cont < CSI_PRIVACY_MAX) {
266 			csi->status = notif.cont.cont;
267 			v4l2_ctrl_s_ctrl(csi->privacy_ctrl, csi->status);
268 		}
269 		break;
270 	case CSI_SET_OWNER:
271 	case CSI_SET_CONF:
272 		memcpy(&csi->cmd_response, &notif, ret);
273 
274 		complete(&csi->cmd_completion);
275 		break;
276 	default:
277 		break;
278 	}
279 }
280 
281 static int mei_csi_set_stream(struct v4l2_subdev *sd, int enable)
282 {
283 	struct mei_csi *csi = sd_to_csi(sd);
284 	s64 freq;
285 	int ret;
286 
287 	if (enable && csi->streaming == 0) {
288 		freq = v4l2_get_link_freq(csi->remote->ctrl_handler, 0, 0);
289 		if (freq < 0) {
290 			dev_err(&csi->cldev->dev,
291 				"error %lld, invalid link_freq\n", freq);
292 			ret = freq;
293 			goto err;
294 		}
295 		csi->link_freq = freq;
296 
297 		/* switch CSI-2 link to host */
298 		ret = csi_set_link_owner(csi, CSI_LINK_HOST);
299 		if (ret < 0)
300 			goto err;
301 
302 		/* configure CSI-2 link */
303 		ret = csi_set_link_cfg(csi);
304 		if (ret < 0)
305 			goto err_switch;
306 
307 		ret = v4l2_subdev_call(csi->remote, video, s_stream, 1);
308 		if (ret)
309 			goto err_switch;
310 	} else if (!enable && csi->streaming == 1) {
311 		v4l2_subdev_call(csi->remote, video, s_stream, 0);
312 
313 		/* switch CSI-2 link to IVSC */
314 		ret = csi_set_link_owner(csi, CSI_LINK_IVSC);
315 		if (ret < 0)
316 			dev_warn(&csi->cldev->dev,
317 				 "failed to switch CSI2 link: %d\n", ret);
318 	}
319 
320 	csi->streaming = enable;
321 
322 	return 0;
323 
324 err_switch:
325 	csi_set_link_owner(csi, CSI_LINK_IVSC);
326 
327 err:
328 	return ret;
329 }
330 
331 static int mei_csi_init_state(struct v4l2_subdev *sd,
332 			      struct v4l2_subdev_state *sd_state)
333 {
334 	struct v4l2_mbus_framefmt *mbusformat;
335 	unsigned int i;
336 
337 	for (i = 0; i < sd->entity.num_pads; i++) {
338 		mbusformat = v4l2_subdev_state_get_format(sd_state, i);
339 		*mbusformat = mei_csi_format_mbus_default;
340 	}
341 
342 	return 0;
343 }
344 
345 static int mei_csi_set_fmt(struct v4l2_subdev *sd,
346 			   struct v4l2_subdev_state *sd_state,
347 			   struct v4l2_subdev_format *format)
348 {
349 	struct v4l2_mbus_framefmt *source_fmt;
350 	struct v4l2_mbus_framefmt *sink_fmt;
351 
352 	sink_fmt = v4l2_subdev_state_get_format(sd_state, CSI_PAD_SINK);
353 	source_fmt = v4l2_subdev_state_get_format(sd_state, CSI_PAD_SOURCE);
354 
355 	if (format->pad) {
356 		*source_fmt = *sink_fmt;
357 
358 		return 0;
359 	}
360 
361 	v4l_bound_align_image(&format->format.width, 1, 65536, 0,
362 			      &format->format.height, 1, 65536, 0, 0);
363 
364 	switch (format->format.code) {
365 	case MEDIA_BUS_FMT_RGB444_1X12:
366 	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_BE:
367 	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE:
368 	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_BE:
369 	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_LE:
370 	case MEDIA_BUS_FMT_RGB565_1X16:
371 	case MEDIA_BUS_FMT_BGR565_2X8_BE:
372 	case MEDIA_BUS_FMT_BGR565_2X8_LE:
373 	case MEDIA_BUS_FMT_RGB565_2X8_BE:
374 	case MEDIA_BUS_FMT_RGB565_2X8_LE:
375 	case MEDIA_BUS_FMT_RGB666_1X18:
376 	case MEDIA_BUS_FMT_RBG888_1X24:
377 	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
378 	case MEDIA_BUS_FMT_BGR888_1X24:
379 	case MEDIA_BUS_FMT_GBR888_1X24:
380 	case MEDIA_BUS_FMT_RGB888_1X24:
381 	case MEDIA_BUS_FMT_RGB888_2X12_BE:
382 	case MEDIA_BUS_FMT_RGB888_2X12_LE:
383 	case MEDIA_BUS_FMT_ARGB8888_1X32:
384 	case MEDIA_BUS_FMT_RGB888_1X32_PADHI:
385 	case MEDIA_BUS_FMT_RGB101010_1X30:
386 	case MEDIA_BUS_FMT_RGB121212_1X36:
387 	case MEDIA_BUS_FMT_RGB161616_1X48:
388 	case MEDIA_BUS_FMT_Y8_1X8:
389 	case MEDIA_BUS_FMT_UV8_1X8:
390 	case MEDIA_BUS_FMT_UYVY8_1_5X8:
391 	case MEDIA_BUS_FMT_VYUY8_1_5X8:
392 	case MEDIA_BUS_FMT_YUYV8_1_5X8:
393 	case MEDIA_BUS_FMT_YVYU8_1_5X8:
394 	case MEDIA_BUS_FMT_UYVY8_2X8:
395 	case MEDIA_BUS_FMT_VYUY8_2X8:
396 	case MEDIA_BUS_FMT_YUYV8_2X8:
397 	case MEDIA_BUS_FMT_YVYU8_2X8:
398 	case MEDIA_BUS_FMT_Y10_1X10:
399 	case MEDIA_BUS_FMT_UYVY10_2X10:
400 	case MEDIA_BUS_FMT_VYUY10_2X10:
401 	case MEDIA_BUS_FMT_YUYV10_2X10:
402 	case MEDIA_BUS_FMT_YVYU10_2X10:
403 	case MEDIA_BUS_FMT_Y12_1X12:
404 	case MEDIA_BUS_FMT_UYVY12_2X12:
405 	case MEDIA_BUS_FMT_VYUY12_2X12:
406 	case MEDIA_BUS_FMT_YUYV12_2X12:
407 	case MEDIA_BUS_FMT_YVYU12_2X12:
408 	case MEDIA_BUS_FMT_UYVY8_1X16:
409 	case MEDIA_BUS_FMT_VYUY8_1X16:
410 	case MEDIA_BUS_FMT_YUYV8_1X16:
411 	case MEDIA_BUS_FMT_YVYU8_1X16:
412 	case MEDIA_BUS_FMT_YDYUYDYV8_1X16:
413 	case MEDIA_BUS_FMT_UYVY10_1X20:
414 	case MEDIA_BUS_FMT_VYUY10_1X20:
415 	case MEDIA_BUS_FMT_YUYV10_1X20:
416 	case MEDIA_BUS_FMT_YVYU10_1X20:
417 	case MEDIA_BUS_FMT_VUY8_1X24:
418 	case MEDIA_BUS_FMT_YUV8_1X24:
419 	case MEDIA_BUS_FMT_UYYVYY8_0_5X24:
420 	case MEDIA_BUS_FMT_UYVY12_1X24:
421 	case MEDIA_BUS_FMT_VYUY12_1X24:
422 	case MEDIA_BUS_FMT_YUYV12_1X24:
423 	case MEDIA_BUS_FMT_YVYU12_1X24:
424 	case MEDIA_BUS_FMT_YUV10_1X30:
425 	case MEDIA_BUS_FMT_UYYVYY10_0_5X30:
426 	case MEDIA_BUS_FMT_AYUV8_1X32:
427 	case MEDIA_BUS_FMT_UYYVYY12_0_5X36:
428 	case MEDIA_BUS_FMT_YUV12_1X36:
429 	case MEDIA_BUS_FMT_YUV16_1X48:
430 	case MEDIA_BUS_FMT_UYYVYY16_0_5X48:
431 	case MEDIA_BUS_FMT_JPEG_1X8:
432 	case MEDIA_BUS_FMT_AHSV8888_1X32:
433 	case MEDIA_BUS_FMT_SBGGR8_1X8:
434 	case MEDIA_BUS_FMT_SGBRG8_1X8:
435 	case MEDIA_BUS_FMT_SGRBG8_1X8:
436 	case MEDIA_BUS_FMT_SRGGB8_1X8:
437 	case MEDIA_BUS_FMT_SBGGR10_1X10:
438 	case MEDIA_BUS_FMT_SGBRG10_1X10:
439 	case MEDIA_BUS_FMT_SGRBG10_1X10:
440 	case MEDIA_BUS_FMT_SRGGB10_1X10:
441 	case MEDIA_BUS_FMT_SBGGR12_1X12:
442 	case MEDIA_BUS_FMT_SGBRG12_1X12:
443 	case MEDIA_BUS_FMT_SGRBG12_1X12:
444 	case MEDIA_BUS_FMT_SRGGB12_1X12:
445 	case MEDIA_BUS_FMT_SBGGR14_1X14:
446 	case MEDIA_BUS_FMT_SGBRG14_1X14:
447 	case MEDIA_BUS_FMT_SGRBG14_1X14:
448 	case MEDIA_BUS_FMT_SRGGB14_1X14:
449 	case MEDIA_BUS_FMT_SBGGR16_1X16:
450 	case MEDIA_BUS_FMT_SGBRG16_1X16:
451 	case MEDIA_BUS_FMT_SGRBG16_1X16:
452 	case MEDIA_BUS_FMT_SRGGB16_1X16:
453 		break;
454 	default:
455 		format->format.code = MEDIA_BUS_FMT_Y8_1X8;
456 		break;
457 	}
458 
459 	if (format->format.field == V4L2_FIELD_ANY)
460 		format->format.field = V4L2_FIELD_NONE;
461 
462 	*sink_fmt = format->format;
463 	*source_fmt = *sink_fmt;
464 
465 	return 0;
466 }
467 
468 static int mei_csi_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
469 {
470 	struct mei_csi *csi = ctrl_to_csi(ctrl);
471 	s64 freq;
472 
473 	if (ctrl->id == V4L2_CID_LINK_FREQ) {
474 		if (!csi->remote)
475 			return -EINVAL;
476 
477 		freq = v4l2_get_link_freq(csi->remote->ctrl_handler, 0, 0);
478 		if (freq < 0) {
479 			dev_err(&csi->cldev->dev,
480 				"error %lld, invalid link_freq\n", freq);
481 			return -EINVAL;
482 		}
483 
484 		link_freq_menu_items[0] = freq;
485 		ctrl->val = 0;
486 
487 		return 0;
488 	}
489 
490 	return -EINVAL;
491 }
492 
493 static const struct v4l2_ctrl_ops mei_csi_ctrl_ops = {
494 	.g_volatile_ctrl = mei_csi_g_volatile_ctrl,
495 };
496 
497 static const struct v4l2_subdev_video_ops mei_csi_video_ops = {
498 	.s_stream = mei_csi_set_stream,
499 };
500 
501 static const struct v4l2_subdev_pad_ops mei_csi_pad_ops = {
502 	.get_fmt = v4l2_subdev_get_fmt,
503 	.set_fmt = mei_csi_set_fmt,
504 };
505 
506 static const struct v4l2_subdev_ops mei_csi_subdev_ops = {
507 	.video = &mei_csi_video_ops,
508 	.pad = &mei_csi_pad_ops,
509 };
510 
511 static const struct v4l2_subdev_internal_ops mei_csi_internal_ops = {
512 	.init_state = mei_csi_init_state,
513 };
514 
515 static const struct media_entity_operations mei_csi_entity_ops = {
516 	.link_validate = v4l2_subdev_link_validate,
517 };
518 
519 static int mei_csi_notify_bound(struct v4l2_async_notifier *notifier,
520 				struct v4l2_subdev *subdev,
521 				struct v4l2_async_connection *asd)
522 {
523 	struct mei_csi *csi = notifier_to_csi(notifier);
524 	int pad;
525 
526 	pad = media_entity_get_fwnode_pad(&subdev->entity, asd->match.fwnode,
527 					  MEDIA_PAD_FL_SOURCE);
528 	if (pad < 0)
529 		return pad;
530 
531 	csi->remote = subdev;
532 	csi->remote_pad = pad;
533 
534 	return media_create_pad_link(&subdev->entity, pad,
535 				     &csi->subdev.entity, CSI_PAD_SINK,
536 				     MEDIA_LNK_FL_ENABLED |
537 				     MEDIA_LNK_FL_IMMUTABLE);
538 }
539 
540 static void mei_csi_notify_unbind(struct v4l2_async_notifier *notifier,
541 				  struct v4l2_subdev *subdev,
542 				  struct v4l2_async_connection *asd)
543 {
544 	struct mei_csi *csi = notifier_to_csi(notifier);
545 
546 	csi->remote = NULL;
547 }
548 
549 static const struct v4l2_async_notifier_operations mei_csi_notify_ops = {
550 	.bound = mei_csi_notify_bound,
551 	.unbind = mei_csi_notify_unbind,
552 };
553 
554 static int mei_csi_init_controls(struct mei_csi *csi)
555 {
556 	u32 max;
557 	int ret;
558 
559 	ret = v4l2_ctrl_handler_init(&csi->ctrl_handler, 2);
560 	if (ret)
561 		return ret;
562 
563 	csi->ctrl_handler.lock = &csi->lock;
564 
565 	max = ARRAY_SIZE(link_freq_menu_items) - 1;
566 	csi->freq_ctrl = v4l2_ctrl_new_int_menu(&csi->ctrl_handler,
567 						&mei_csi_ctrl_ops,
568 						V4L2_CID_LINK_FREQ,
569 						max,
570 						0,
571 						link_freq_menu_items);
572 	if (csi->freq_ctrl)
573 		csi->freq_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY |
574 					 V4L2_CTRL_FLAG_VOLATILE;
575 
576 	csi->privacy_ctrl = v4l2_ctrl_new_std(&csi->ctrl_handler, NULL,
577 					      V4L2_CID_PRIVACY, 0, 1, 1, 0);
578 	if (csi->privacy_ctrl)
579 		csi->privacy_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
580 
581 	if (csi->ctrl_handler.error)
582 		return csi->ctrl_handler.error;
583 
584 	csi->subdev.ctrl_handler = &csi->ctrl_handler;
585 
586 	return 0;
587 }
588 
589 static int mei_csi_parse_firmware(struct mei_csi *csi)
590 {
591 	struct v4l2_fwnode_endpoint v4l2_ep = {
592 		.bus_type = V4L2_MBUS_CSI2_DPHY,
593 	};
594 	struct device *dev = &csi->cldev->dev;
595 	struct v4l2_async_connection *asd;
596 	struct fwnode_handle *sink_ep, *source_ep;
597 	int ret;
598 
599 	sink_ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0, 0);
600 	if (!sink_ep) {
601 		dev_err(dev, "can't obtain sink endpoint\n");
602 		return -EINVAL;
603 	}
604 
605 	v4l2_async_subdev_nf_init(&csi->notifier, &csi->subdev);
606 	csi->notifier.ops = &mei_csi_notify_ops;
607 
608 	ret = v4l2_fwnode_endpoint_parse(sink_ep, &v4l2_ep);
609 	if (ret) {
610 		dev_err(dev, "could not parse v4l2 sink endpoint\n");
611 		goto out_nf_cleanup;
612 	}
613 
614 	csi->nr_of_lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
615 
616 	source_ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 1, 0, 0);
617 	if (!source_ep) {
618 		ret = -ENOTCONN;
619 		dev_err(dev, "can't obtain source endpoint\n");
620 		goto out_nf_cleanup;
621 	}
622 
623 	ret = v4l2_fwnode_endpoint_parse(source_ep, &v4l2_ep);
624 	fwnode_handle_put(source_ep);
625 	if (ret) {
626 		dev_err(dev, "could not parse v4l2 source endpoint\n");
627 		goto out_nf_cleanup;
628 	}
629 
630 	if (csi->nr_of_lanes != v4l2_ep.bus.mipi_csi2.num_data_lanes) {
631 		ret = -EINVAL;
632 		dev_err(dev,
633 			"the number of lanes does not match (%u vs. %u)\n",
634 			csi->nr_of_lanes, v4l2_ep.bus.mipi_csi2.num_data_lanes);
635 		goto out_nf_cleanup;
636 	}
637 
638 	asd = v4l2_async_nf_add_fwnode_remote(&csi->notifier, sink_ep,
639 					      struct v4l2_async_connection);
640 	if (IS_ERR(asd)) {
641 		ret = PTR_ERR(asd);
642 		goto out_nf_cleanup;
643 	}
644 
645 	ret = v4l2_async_nf_register(&csi->notifier);
646 	if (ret)
647 		goto out_nf_cleanup;
648 
649 	fwnode_handle_put(sink_ep);
650 
651 	return 0;
652 
653 out_nf_cleanup:
654 	v4l2_async_nf_cleanup(&csi->notifier);
655 	fwnode_handle_put(sink_ep);
656 
657 	return ret;
658 }
659 
660 static int mei_csi_probe(struct mei_cl_device *cldev,
661 			 const struct mei_cl_device_id *id)
662 {
663 	struct device *dev = &cldev->dev;
664 	struct mei_csi *csi;
665 	int ret;
666 
667 	if (!dev_fwnode(dev))
668 		return -EPROBE_DEFER;
669 
670 	csi = devm_kzalloc(dev, sizeof(struct mei_csi), GFP_KERNEL);
671 	if (!csi)
672 		return -ENOMEM;
673 
674 	csi->cldev = cldev;
675 	mutex_init(&csi->lock);
676 	init_completion(&csi->cmd_completion);
677 
678 	mei_cldev_set_drvdata(cldev, csi);
679 
680 	ret = mei_cldev_enable(cldev);
681 	if (ret < 0) {
682 		dev_err(dev, "mei_cldev_enable failed: %d\n", ret);
683 		goto destroy_mutex;
684 	}
685 
686 	ret = mei_cldev_register_rx_cb(cldev, mei_csi_rx);
687 	if (ret) {
688 		dev_err(dev, "event cb registration failed: %d\n", ret);
689 		goto err_disable;
690 	}
691 
692 	ret = mei_csi_parse_firmware(csi);
693 	if (ret)
694 		goto err_disable;
695 
696 	csi->subdev.dev = &cldev->dev;
697 	csi->subdev.state_lock = &csi->lock;
698 	v4l2_subdev_init(&csi->subdev, &mei_csi_subdev_ops);
699 	csi->subdev.internal_ops = &mei_csi_internal_ops;
700 	v4l2_set_subdevdata(&csi->subdev, csi);
701 	csi->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE |
702 			    V4L2_SUBDEV_FL_HAS_EVENTS;
703 	csi->subdev.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
704 	csi->subdev.entity.ops = &mei_csi_entity_ops;
705 
706 	snprintf(csi->subdev.name, sizeof(csi->subdev.name),
707 		 MEI_CSI_ENTITY_NAME);
708 
709 	ret = mei_csi_init_controls(csi);
710 	if (ret)
711 		goto err_ctrl_handler;
712 
713 	csi->pads[CSI_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
714 	csi->pads[CSI_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
715 	ret = media_entity_pads_init(&csi->subdev.entity, CSI_NUM_PADS,
716 				     csi->pads);
717 	if (ret)
718 		goto err_ctrl_handler;
719 
720 	ret = v4l2_subdev_init_finalize(&csi->subdev);
721 	if (ret < 0)
722 		goto err_entity;
723 
724 	ret = v4l2_async_register_subdev(&csi->subdev);
725 	if (ret < 0)
726 		goto err_subdev;
727 
728 	pm_runtime_enable(&cldev->dev);
729 
730 	return 0;
731 
732 err_subdev:
733 	v4l2_subdev_cleanup(&csi->subdev);
734 
735 err_entity:
736 	media_entity_cleanup(&csi->subdev.entity);
737 
738 err_ctrl_handler:
739 	v4l2_ctrl_handler_free(&csi->ctrl_handler);
740 	v4l2_async_nf_unregister(&csi->notifier);
741 	v4l2_async_nf_cleanup(&csi->notifier);
742 
743 err_disable:
744 	mei_cldev_disable(cldev);
745 
746 destroy_mutex:
747 	mutex_destroy(&csi->lock);
748 
749 	return ret;
750 }
751 
752 static void mei_csi_remove(struct mei_cl_device *cldev)
753 {
754 	struct mei_csi *csi = mei_cldev_get_drvdata(cldev);
755 
756 	v4l2_async_nf_unregister(&csi->notifier);
757 	v4l2_async_nf_cleanup(&csi->notifier);
758 	v4l2_ctrl_handler_free(&csi->ctrl_handler);
759 	v4l2_async_unregister_subdev(&csi->subdev);
760 	v4l2_subdev_cleanup(&csi->subdev);
761 	media_entity_cleanup(&csi->subdev.entity);
762 
763 	pm_runtime_disable(&cldev->dev);
764 
765 	mutex_destroy(&csi->lock);
766 }
767 
768 #define MEI_CSI_UUID UUID_LE(0x92335FCF, 0x3203, 0x4472, \
769 			     0xAF, 0x93, 0x7b, 0x44, 0x53, 0xAC, 0x29, 0xDA)
770 
771 static const struct mei_cl_device_id mei_csi_tbl[] = {
772 	{ .uuid = MEI_CSI_UUID, .version = MEI_CL_VERSION_ANY },
773 	{ /* sentinel */ }
774 };
775 MODULE_DEVICE_TABLE(mei, mei_csi_tbl);
776 
777 static struct mei_cl_driver mei_csi_driver = {
778 	.id_table = mei_csi_tbl,
779 	.name = KBUILD_MODNAME,
780 
781 	.probe = mei_csi_probe,
782 	.remove = mei_csi_remove,
783 };
784 
785 module_mei_cl_driver(mei_csi_driver);
786 
787 MODULE_AUTHOR("Wentong Wu <wentong.wu@intel.com>");
788 MODULE_AUTHOR("Zhifeng Wang <zhifeng.wang@intel.com>");
789 MODULE_DESCRIPTION("Device driver for IVSC CSI");
790 MODULE_LICENSE("GPL");
791