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_DRIVER_NAME "ivsc_csi"
34 #define MEI_CSI_ENTITY_NAME "Intel IVSC CSI"
35 
36 #define MEI_CSI_LINK_FREQ_400MHZ 400000000ULL
37 
38 /* the 5s used here is based on experiment */
39 #define CSI_CMD_TIMEOUT (5 * HZ)
40 /* to setup CSI-2 link an extra delay needed and determined experimentally */
41 #define CSI_FW_READY_DELAY_MS 100
42 /* link frequency unit is 100kHz */
43 #define CSI_LINK_FREQ(x) ((u32)(div_u64(x, 100 * HZ_PER_KHZ)))
44 
45 /*
46  * identify the command id supported by firmware
47  * IPC, as well as the privacy notification id
48  * used when processing privacy event.
49  */
50 enum csi_cmd_id {
51 	/* used to set csi ownership */
52 	CSI_SET_OWNER = 0,
53 
54 	/* used to configure CSI-2 link */
55 	CSI_SET_CONF = 2,
56 
57 	/* privacy notification id used when privacy state changes */
58 	CSI_PRIVACY_NOTIF = 6,
59 };
60 
61 /* CSI-2 link ownership definition */
62 enum csi_link_owner {
63 	CSI_LINK_IVSC,
64 	CSI_LINK_HOST,
65 };
66 
67 /* privacy status definition */
68 enum ivsc_privacy_status {
69 	CSI_PRIVACY_OFF,
70 	CSI_PRIVACY_ON,
71 	CSI_PRIVACY_MAX,
72 };
73 
74 enum csi_pads {
75 	CSI_PAD_SOURCE,
76 	CSI_PAD_SINK,
77 	CSI_NUM_PADS
78 };
79 
80 /* configuration of the CSI-2 link between host and IVSC */
81 struct csi_link_cfg {
82 	/* number of data lanes used on the CSI-2 link */
83 	u32 nr_of_lanes;
84 
85 	/* frequency of the CSI-2 link */
86 	u32 link_freq;
87 
88 	/* for future use */
89 	u32 rsvd[2];
90 } __packed;
91 
92 /* CSI command structure */
93 struct csi_cmd {
94 	u32 cmd_id;
95 	union _cmd_param {
96 		u32 param;
97 		struct csi_link_cfg conf;
98 	} param;
99 } __packed;
100 
101 /* CSI notification structure */
102 struct csi_notif {
103 	u32 cmd_id;
104 	int status;
105 	union _resp_cont {
106 		u32 cont;
107 		struct csi_link_cfg conf;
108 	} cont;
109 } __packed;
110 
111 struct mei_csi {
112 	struct mei_cl_device *cldev;
113 
114 	/* command response */
115 	struct csi_notif cmd_response;
116 	/* used to wait for command response from firmware */
117 	struct completion cmd_completion;
118 	/* protect command download */
119 	struct mutex lock;
120 
121 	struct v4l2_subdev subdev;
122 	struct v4l2_subdev *remote;
123 	struct v4l2_async_notifier notifier;
124 	struct v4l2_ctrl_handler ctrl_handler;
125 	struct v4l2_ctrl *freq_ctrl;
126 	struct v4l2_ctrl *privacy_ctrl;
127 	unsigned int remote_pad;
128 	/* start streaming or not */
129 	int streaming;
130 
131 	struct media_pad pads[CSI_NUM_PADS];
132 	struct v4l2_mbus_framefmt format_mbus[CSI_NUM_PADS];
133 
134 	/* number of data lanes used on the CSI-2 link */
135 	u32 nr_of_lanes;
136 	/* frequency of the CSI-2 link */
137 	u64 link_freq;
138 
139 	/* privacy status */
140 	enum ivsc_privacy_status status;
141 };
142 
143 static const struct v4l2_mbus_framefmt mei_csi_format_mbus_default = {
144 	.width = 1,
145 	.height = 1,
146 	.code = MEDIA_BUS_FMT_Y8_1X8,
147 	.field = V4L2_FIELD_NONE,
148 };
149 
150 static s64 link_freq_menu_items[] = {
151 	MEI_CSI_LINK_FREQ_400MHZ
152 };
153 
154 static inline struct mei_csi *notifier_to_csi(struct v4l2_async_notifier *n)
155 {
156 	return container_of(n, struct mei_csi, notifier);
157 }
158 
159 static inline struct mei_csi *sd_to_csi(struct v4l2_subdev *sd)
160 {
161 	return container_of(sd, struct mei_csi, subdev);
162 }
163 
164 static inline struct mei_csi *ctrl_to_csi(struct v4l2_ctrl *ctrl)
165 {
166 	return container_of(ctrl->handler, struct mei_csi, ctrl_handler);
167 }
168 
169 /* send a command to firmware and mutex must be held by caller */
170 static int mei_csi_send(struct mei_csi *csi, u8 *buf, size_t len)
171 {
172 	struct csi_cmd *cmd = (struct csi_cmd *)buf;
173 	int ret;
174 
175 	reinit_completion(&csi->cmd_completion);
176 
177 	ret = mei_cldev_send(csi->cldev, buf, len);
178 	if (ret < 0)
179 		goto out;
180 
181 	ret = wait_for_completion_killable_timeout(&csi->cmd_completion,
182 						   CSI_CMD_TIMEOUT);
183 	if (ret < 0) {
184 		goto out;
185 	} else if (!ret) {
186 		ret = -ETIMEDOUT;
187 		goto out;
188 	}
189 
190 	/* command response status */
191 	ret = csi->cmd_response.status;
192 	if (ret) {
193 		ret = -EINVAL;
194 		goto out;
195 	}
196 
197 	if (csi->cmd_response.cmd_id != cmd->cmd_id)
198 		ret = -EINVAL;
199 
200 out:
201 	return ret;
202 }
203 
204 /* set CSI-2 link ownership */
205 static int csi_set_link_owner(struct mei_csi *csi, enum csi_link_owner owner)
206 {
207 	struct csi_cmd cmd = { 0 };
208 	size_t cmd_size;
209 	int ret;
210 
211 	cmd.cmd_id = CSI_SET_OWNER;
212 	cmd.param.param = owner;
213 	cmd_size = sizeof(cmd.cmd_id) + sizeof(cmd.param.param);
214 
215 	mutex_lock(&csi->lock);
216 
217 	ret = mei_csi_send(csi, (u8 *)&cmd, cmd_size);
218 
219 	mutex_unlock(&csi->lock);
220 
221 	return ret;
222 }
223 
224 /* configure CSI-2 link between host and IVSC */
225 static int csi_set_link_cfg(struct mei_csi *csi)
226 {
227 	struct csi_cmd cmd = { 0 };
228 	size_t cmd_size;
229 	int ret;
230 
231 	cmd.cmd_id = CSI_SET_CONF;
232 	cmd.param.conf.nr_of_lanes = csi->nr_of_lanes;
233 	cmd.param.conf.link_freq = CSI_LINK_FREQ(csi->link_freq);
234 	cmd_size = sizeof(cmd.cmd_id) + sizeof(cmd.param.conf);
235 
236 	mutex_lock(&csi->lock);
237 
238 	ret = mei_csi_send(csi, (u8 *)&cmd, cmd_size);
239 	/*
240 	 * wait configuration ready if download success. placing
241 	 * delay under mutex is to make sure current command flow
242 	 * completed before starting a possible new one.
243 	 */
244 	if (!ret)
245 		msleep(CSI_FW_READY_DELAY_MS);
246 
247 	mutex_unlock(&csi->lock);
248 
249 	return ret;
250 }
251 
252 /* callback for receive */
253 static void mei_csi_rx(struct mei_cl_device *cldev)
254 {
255 	struct mei_csi *csi = mei_cldev_get_drvdata(cldev);
256 	struct csi_notif notif = { 0 };
257 	int ret;
258 
259 	ret = mei_cldev_recv(cldev, (u8 *)&notif, sizeof(notif));
260 	if (ret < 0) {
261 		dev_err(&cldev->dev, "recv error: %d\n", ret);
262 		return;
263 	}
264 
265 	switch (notif.cmd_id) {
266 	case CSI_PRIVACY_NOTIF:
267 		if (notif.cont.cont < CSI_PRIVACY_MAX) {
268 			csi->status = notif.cont.cont;
269 			v4l2_ctrl_s_ctrl(csi->privacy_ctrl, csi->status);
270 		}
271 		break;
272 	case CSI_SET_OWNER:
273 	case CSI_SET_CONF:
274 		memcpy(&csi->cmd_response, &notif, ret);
275 
276 		complete(&csi->cmd_completion);
277 		break;
278 	default:
279 		break;
280 	}
281 }
282 
283 static int mei_csi_set_stream(struct v4l2_subdev *sd, int enable)
284 {
285 	struct mei_csi *csi = sd_to_csi(sd);
286 	s64 freq;
287 	int ret;
288 
289 	if (enable && csi->streaming == 0) {
290 		freq = v4l2_get_link_freq(csi->remote->ctrl_handler, 0, 0);
291 		if (freq < 0) {
292 			dev_err(&csi->cldev->dev,
293 				"error %lld, invalid link_freq\n", freq);
294 			ret = freq;
295 			goto err;
296 		}
297 		csi->link_freq = freq;
298 
299 		/* switch CSI-2 link to host */
300 		ret = csi_set_link_owner(csi, CSI_LINK_HOST);
301 		if (ret < 0)
302 			goto err;
303 
304 		/* configure CSI-2 link */
305 		ret = csi_set_link_cfg(csi);
306 		if (ret < 0)
307 			goto err_switch;
308 
309 		ret = v4l2_subdev_call(csi->remote, video, s_stream, 1);
310 		if (ret)
311 			goto err_switch;
312 	} else if (!enable && csi->streaming == 1) {
313 		v4l2_subdev_call(csi->remote, video, s_stream, 0);
314 
315 		/* switch CSI-2 link to IVSC */
316 		ret = csi_set_link_owner(csi, CSI_LINK_IVSC);
317 		if (ret < 0)
318 			dev_warn(&csi->cldev->dev,
319 				 "failed to switch CSI2 link: %d\n", ret);
320 	}
321 
322 	csi->streaming = enable;
323 
324 	return 0;
325 
326 err_switch:
327 	csi_set_link_owner(csi, CSI_LINK_IVSC);
328 
329 err:
330 	return ret;
331 }
332 
333 static struct v4l2_mbus_framefmt *
334 mei_csi_get_pad_format(struct v4l2_subdev *sd,
335 		       struct v4l2_subdev_state *sd_state,
336 		       unsigned int pad, u32 which)
337 {
338 	struct mei_csi *csi = sd_to_csi(sd);
339 
340 	switch (which) {
341 	case V4L2_SUBDEV_FORMAT_TRY:
342 		return v4l2_subdev_get_try_format(sd, sd_state, pad);
343 	case V4L2_SUBDEV_FORMAT_ACTIVE:
344 		return &csi->format_mbus[pad];
345 	default:
346 		return NULL;
347 	}
348 }
349 
350 static int mei_csi_init_cfg(struct v4l2_subdev *sd,
351 			    struct v4l2_subdev_state *sd_state)
352 {
353 	struct v4l2_mbus_framefmt *mbusformat;
354 	struct mei_csi *csi = sd_to_csi(sd);
355 	unsigned int i;
356 
357 	mutex_lock(&csi->lock);
358 
359 	for (i = 0; i < sd->entity.num_pads; i++) {
360 		mbusformat = v4l2_subdev_get_try_format(sd, sd_state, i);
361 		*mbusformat = mei_csi_format_mbus_default;
362 	}
363 
364 	mutex_unlock(&csi->lock);
365 
366 	return 0;
367 }
368 
369 static int mei_csi_get_fmt(struct v4l2_subdev *sd,
370 			   struct v4l2_subdev_state *sd_state,
371 			   struct v4l2_subdev_format *format)
372 {
373 	struct v4l2_mbus_framefmt *mbusformat;
374 	struct mei_csi *csi = sd_to_csi(sd);
375 
376 	mutex_lock(&csi->lock);
377 
378 	mbusformat = mei_csi_get_pad_format(sd, sd_state, format->pad,
379 					    format->which);
380 	if (mbusformat)
381 		format->format = *mbusformat;
382 
383 	mutex_unlock(&csi->lock);
384 
385 	return 0;
386 }
387 
388 static int mei_csi_set_fmt(struct v4l2_subdev *sd,
389 			   struct v4l2_subdev_state *sd_state,
390 			   struct v4l2_subdev_format *format)
391 {
392 	struct v4l2_mbus_framefmt *source_mbusformat;
393 	struct v4l2_mbus_framefmt *mbusformat;
394 	struct mei_csi *csi = sd_to_csi(sd);
395 	struct media_pad *pad;
396 
397 	mbusformat = mei_csi_get_pad_format(sd, sd_state, format->pad,
398 					    format->which);
399 	if (!mbusformat)
400 		return -EINVAL;
401 
402 	source_mbusformat = mei_csi_get_pad_format(sd, sd_state, CSI_PAD_SOURCE,
403 						   format->which);
404 	if (!source_mbusformat)
405 		return -EINVAL;
406 
407 	v4l_bound_align_image(&format->format.width, 1, 65536, 0,
408 			      &format->format.height, 1, 65536, 0, 0);
409 
410 	switch (format->format.code) {
411 	case MEDIA_BUS_FMT_RGB444_1X12:
412 	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_BE:
413 	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE:
414 	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_BE:
415 	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_LE:
416 	case MEDIA_BUS_FMT_RGB565_1X16:
417 	case MEDIA_BUS_FMT_BGR565_2X8_BE:
418 	case MEDIA_BUS_FMT_BGR565_2X8_LE:
419 	case MEDIA_BUS_FMT_RGB565_2X8_BE:
420 	case MEDIA_BUS_FMT_RGB565_2X8_LE:
421 	case MEDIA_BUS_FMT_RGB666_1X18:
422 	case MEDIA_BUS_FMT_RBG888_1X24:
423 	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
424 	case MEDIA_BUS_FMT_BGR888_1X24:
425 	case MEDIA_BUS_FMT_GBR888_1X24:
426 	case MEDIA_BUS_FMT_RGB888_1X24:
427 	case MEDIA_BUS_FMT_RGB888_2X12_BE:
428 	case MEDIA_BUS_FMT_RGB888_2X12_LE:
429 	case MEDIA_BUS_FMT_ARGB8888_1X32:
430 	case MEDIA_BUS_FMT_RGB888_1X32_PADHI:
431 	case MEDIA_BUS_FMT_RGB101010_1X30:
432 	case MEDIA_BUS_FMT_RGB121212_1X36:
433 	case MEDIA_BUS_FMT_RGB161616_1X48:
434 	case MEDIA_BUS_FMT_Y8_1X8:
435 	case MEDIA_BUS_FMT_UV8_1X8:
436 	case MEDIA_BUS_FMT_UYVY8_1_5X8:
437 	case MEDIA_BUS_FMT_VYUY8_1_5X8:
438 	case MEDIA_BUS_FMT_YUYV8_1_5X8:
439 	case MEDIA_BUS_FMT_YVYU8_1_5X8:
440 	case MEDIA_BUS_FMT_UYVY8_2X8:
441 	case MEDIA_BUS_FMT_VYUY8_2X8:
442 	case MEDIA_BUS_FMT_YUYV8_2X8:
443 	case MEDIA_BUS_FMT_YVYU8_2X8:
444 	case MEDIA_BUS_FMT_Y10_1X10:
445 	case MEDIA_BUS_FMT_UYVY10_2X10:
446 	case MEDIA_BUS_FMT_VYUY10_2X10:
447 	case MEDIA_BUS_FMT_YUYV10_2X10:
448 	case MEDIA_BUS_FMT_YVYU10_2X10:
449 	case MEDIA_BUS_FMT_Y12_1X12:
450 	case MEDIA_BUS_FMT_UYVY12_2X12:
451 	case MEDIA_BUS_FMT_VYUY12_2X12:
452 	case MEDIA_BUS_FMT_YUYV12_2X12:
453 	case MEDIA_BUS_FMT_YVYU12_2X12:
454 	case MEDIA_BUS_FMT_UYVY8_1X16:
455 	case MEDIA_BUS_FMT_VYUY8_1X16:
456 	case MEDIA_BUS_FMT_YUYV8_1X16:
457 	case MEDIA_BUS_FMT_YVYU8_1X16:
458 	case MEDIA_BUS_FMT_YDYUYDYV8_1X16:
459 	case MEDIA_BUS_FMT_UYVY10_1X20:
460 	case MEDIA_BUS_FMT_VYUY10_1X20:
461 	case MEDIA_BUS_FMT_YUYV10_1X20:
462 	case MEDIA_BUS_FMT_YVYU10_1X20:
463 	case MEDIA_BUS_FMT_VUY8_1X24:
464 	case MEDIA_BUS_FMT_YUV8_1X24:
465 	case MEDIA_BUS_FMT_UYYVYY8_0_5X24:
466 	case MEDIA_BUS_FMT_UYVY12_1X24:
467 	case MEDIA_BUS_FMT_VYUY12_1X24:
468 	case MEDIA_BUS_FMT_YUYV12_1X24:
469 	case MEDIA_BUS_FMT_YVYU12_1X24:
470 	case MEDIA_BUS_FMT_YUV10_1X30:
471 	case MEDIA_BUS_FMT_UYYVYY10_0_5X30:
472 	case MEDIA_BUS_FMT_AYUV8_1X32:
473 	case MEDIA_BUS_FMT_UYYVYY12_0_5X36:
474 	case MEDIA_BUS_FMT_YUV12_1X36:
475 	case MEDIA_BUS_FMT_YUV16_1X48:
476 	case MEDIA_BUS_FMT_UYYVYY16_0_5X48:
477 	case MEDIA_BUS_FMT_JPEG_1X8:
478 	case MEDIA_BUS_FMT_AHSV8888_1X32:
479 	case MEDIA_BUS_FMT_SBGGR8_1X8:
480 	case MEDIA_BUS_FMT_SGBRG8_1X8:
481 	case MEDIA_BUS_FMT_SGRBG8_1X8:
482 	case MEDIA_BUS_FMT_SRGGB8_1X8:
483 	case MEDIA_BUS_FMT_SBGGR10_1X10:
484 	case MEDIA_BUS_FMT_SGBRG10_1X10:
485 	case MEDIA_BUS_FMT_SGRBG10_1X10:
486 	case MEDIA_BUS_FMT_SRGGB10_1X10:
487 	case MEDIA_BUS_FMT_SBGGR12_1X12:
488 	case MEDIA_BUS_FMT_SGBRG12_1X12:
489 	case MEDIA_BUS_FMT_SGRBG12_1X12:
490 	case MEDIA_BUS_FMT_SRGGB12_1X12:
491 	case MEDIA_BUS_FMT_SBGGR14_1X14:
492 	case MEDIA_BUS_FMT_SGBRG14_1X14:
493 	case MEDIA_BUS_FMT_SGRBG14_1X14:
494 	case MEDIA_BUS_FMT_SRGGB14_1X14:
495 	case MEDIA_BUS_FMT_SBGGR16_1X16:
496 	case MEDIA_BUS_FMT_SGBRG16_1X16:
497 	case MEDIA_BUS_FMT_SGRBG16_1X16:
498 	case MEDIA_BUS_FMT_SRGGB16_1X16:
499 		break;
500 	default:
501 		format->format.code = MEDIA_BUS_FMT_Y8_1X8;
502 		break;
503 	}
504 
505 	if (format->format.field == V4L2_FIELD_ANY)
506 		format->format.field = V4L2_FIELD_NONE;
507 
508 	mutex_lock(&csi->lock);
509 
510 	pad = &csi->pads[format->pad];
511 	if (pad->flags & MEDIA_PAD_FL_SOURCE)
512 		format->format = csi->format_mbus[CSI_PAD_SINK];
513 
514 	*mbusformat = format->format;
515 
516 	if (pad->flags & MEDIA_PAD_FL_SINK)
517 		*source_mbusformat = format->format;
518 
519 	mutex_unlock(&csi->lock);
520 
521 	return 0;
522 }
523 
524 static int mei_csi_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
525 {
526 	struct mei_csi *csi = ctrl_to_csi(ctrl);
527 	s64 freq;
528 
529 	if (ctrl->id == V4L2_CID_LINK_FREQ) {
530 		if (!csi->remote)
531 			return -EINVAL;
532 
533 		freq = v4l2_get_link_freq(csi->remote->ctrl_handler, 0, 0);
534 		if (freq < 0) {
535 			dev_err(&csi->cldev->dev,
536 				"error %lld, invalid link_freq\n", freq);
537 			return -EINVAL;
538 		}
539 
540 		link_freq_menu_items[0] = freq;
541 		ctrl->val = 0;
542 
543 		return 0;
544 	}
545 
546 	return -EINVAL;
547 }
548 
549 static const struct v4l2_ctrl_ops mei_csi_ctrl_ops = {
550 	.g_volatile_ctrl = mei_csi_g_volatile_ctrl,
551 };
552 
553 static const struct v4l2_subdev_video_ops mei_csi_video_ops = {
554 	.s_stream = mei_csi_set_stream,
555 };
556 
557 static const struct v4l2_subdev_pad_ops mei_csi_pad_ops = {
558 	.init_cfg = mei_csi_init_cfg,
559 	.get_fmt = mei_csi_get_fmt,
560 	.set_fmt = mei_csi_set_fmt,
561 };
562 
563 static const struct v4l2_subdev_ops mei_csi_subdev_ops = {
564 	.video = &mei_csi_video_ops,
565 	.pad = &mei_csi_pad_ops,
566 };
567 
568 static const struct media_entity_operations mei_csi_entity_ops = {
569 	.link_validate = v4l2_subdev_link_validate,
570 };
571 
572 static int mei_csi_notify_bound(struct v4l2_async_notifier *notifier,
573 				struct v4l2_subdev *subdev,
574 				struct v4l2_async_connection *asd)
575 {
576 	struct mei_csi *csi = notifier_to_csi(notifier);
577 	int pad;
578 
579 	pad = media_entity_get_fwnode_pad(&subdev->entity, asd->match.fwnode,
580 					  MEDIA_PAD_FL_SOURCE);
581 	if (pad < 0)
582 		return pad;
583 
584 	csi->remote = subdev;
585 	csi->remote_pad = pad;
586 
587 	return media_create_pad_link(&subdev->entity, pad,
588 				     &csi->subdev.entity, 1,
589 				     MEDIA_LNK_FL_ENABLED |
590 				     MEDIA_LNK_FL_IMMUTABLE);
591 }
592 
593 static void mei_csi_notify_unbind(struct v4l2_async_notifier *notifier,
594 				  struct v4l2_subdev *subdev,
595 				  struct v4l2_async_connection *asd)
596 {
597 	struct mei_csi *csi = notifier_to_csi(notifier);
598 
599 	csi->remote = NULL;
600 }
601 
602 static const struct v4l2_async_notifier_operations mei_csi_notify_ops = {
603 	.bound = mei_csi_notify_bound,
604 	.unbind = mei_csi_notify_unbind,
605 };
606 
607 static int mei_csi_init_controls(struct mei_csi *csi)
608 {
609 	u32 max;
610 	int ret;
611 
612 	ret = v4l2_ctrl_handler_init(&csi->ctrl_handler, 2);
613 	if (ret)
614 		return ret;
615 
616 	csi->ctrl_handler.lock = &csi->lock;
617 
618 	max = ARRAY_SIZE(link_freq_menu_items) - 1;
619 	csi->freq_ctrl = v4l2_ctrl_new_int_menu(&csi->ctrl_handler,
620 						&mei_csi_ctrl_ops,
621 						V4L2_CID_LINK_FREQ,
622 						max,
623 						0,
624 						link_freq_menu_items);
625 	if (csi->freq_ctrl)
626 		csi->freq_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY |
627 					 V4L2_CTRL_FLAG_VOLATILE;
628 
629 	csi->privacy_ctrl = v4l2_ctrl_new_std(&csi->ctrl_handler, NULL,
630 					      V4L2_CID_PRIVACY, 0, 1, 1, 0);
631 	if (csi->privacy_ctrl)
632 		csi->privacy_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
633 
634 	if (csi->ctrl_handler.error)
635 		return csi->ctrl_handler.error;
636 
637 	csi->subdev.ctrl_handler = &csi->ctrl_handler;
638 
639 	return 0;
640 }
641 
642 static int mei_csi_parse_firmware(struct mei_csi *csi)
643 {
644 	struct v4l2_fwnode_endpoint v4l2_ep = {
645 		.bus_type = V4L2_MBUS_CSI2_DPHY,
646 	};
647 	struct device *dev = &csi->cldev->dev;
648 	struct v4l2_async_connection *asd;
649 	struct fwnode_handle *fwnode;
650 	struct fwnode_handle *ep;
651 	int ret;
652 
653 	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0, 0);
654 	if (!ep) {
655 		dev_err(dev, "not connected to subdevice\n");
656 		return -EINVAL;
657 	}
658 
659 	ret = v4l2_fwnode_endpoint_parse(ep, &v4l2_ep);
660 	if (ret) {
661 		dev_err(dev, "could not parse v4l2 endpoint\n");
662 		fwnode_handle_put(ep);
663 		return -EINVAL;
664 	}
665 
666 	fwnode = fwnode_graph_get_remote_endpoint(ep);
667 	fwnode_handle_put(ep);
668 
669 	v4l2_async_subdev_nf_init(&csi->notifier, &csi->subdev);
670 	csi->notifier.ops = &mei_csi_notify_ops;
671 
672 	asd = v4l2_async_nf_add_fwnode(&csi->notifier, fwnode,
673 				       struct v4l2_async_connection);
674 	if (IS_ERR(asd)) {
675 		fwnode_handle_put(fwnode);
676 		return PTR_ERR(asd);
677 	}
678 
679 	ret = v4l2_fwnode_endpoint_alloc_parse(fwnode, &v4l2_ep);
680 	fwnode_handle_put(fwnode);
681 	if (ret)
682 		return ret;
683 	csi->nr_of_lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
684 
685 	ret = v4l2_async_nf_register(&csi->notifier);
686 	if (ret)
687 		v4l2_async_nf_cleanup(&csi->notifier);
688 
689 	v4l2_fwnode_endpoint_free(&v4l2_ep);
690 
691 	return ret;
692 }
693 
694 static int mei_csi_probe(struct mei_cl_device *cldev,
695 			 const struct mei_cl_device_id *id)
696 {
697 	struct device *dev = &cldev->dev;
698 	struct mei_csi *csi;
699 	int ret;
700 
701 	if (!dev_fwnode(dev))
702 		return -EPROBE_DEFER;
703 
704 	csi = devm_kzalloc(dev, sizeof(struct mei_csi), GFP_KERNEL);
705 	if (!csi)
706 		return -ENOMEM;
707 
708 	csi->cldev = cldev;
709 	mutex_init(&csi->lock);
710 	init_completion(&csi->cmd_completion);
711 
712 	mei_cldev_set_drvdata(cldev, csi);
713 
714 	ret = mei_cldev_enable(cldev);
715 	if (ret < 0) {
716 		dev_err(dev, "mei_cldev_enable failed: %d\n", ret);
717 		goto destroy_mutex;
718 	}
719 
720 	ret = mei_cldev_register_rx_cb(cldev, mei_csi_rx);
721 	if (ret) {
722 		dev_err(dev, "event cb registration failed: %d\n", ret);
723 		goto err_disable;
724 	}
725 
726 	ret = mei_csi_parse_firmware(csi);
727 	if (ret)
728 		goto err_disable;
729 
730 	csi->subdev.dev = &cldev->dev;
731 	v4l2_subdev_init(&csi->subdev, &mei_csi_subdev_ops);
732 	v4l2_set_subdevdata(&csi->subdev, csi);
733 	csi->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE |
734 			    V4L2_SUBDEV_FL_HAS_EVENTS;
735 	csi->subdev.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
736 	csi->subdev.entity.ops = &mei_csi_entity_ops;
737 
738 	snprintf(csi->subdev.name, sizeof(csi->subdev.name),
739 		 MEI_CSI_ENTITY_NAME);
740 
741 	ret = mei_csi_init_controls(csi);
742 	if (ret)
743 		goto err_ctrl_handler;
744 
745 	csi->format_mbus[CSI_PAD_SOURCE] = mei_csi_format_mbus_default;
746 	csi->format_mbus[CSI_PAD_SINK] = mei_csi_format_mbus_default;
747 
748 	csi->pads[CSI_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
749 	csi->pads[CSI_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
750 	ret = media_entity_pads_init(&csi->subdev.entity, CSI_NUM_PADS,
751 				     csi->pads);
752 	if (ret)
753 		goto err_ctrl_handler;
754 
755 	ret = v4l2_subdev_init_finalize(&csi->subdev);
756 	if (ret < 0)
757 		goto err_entity;
758 
759 	ret = v4l2_async_register_subdev(&csi->subdev);
760 	if (ret < 0)
761 		goto err_subdev;
762 
763 	pm_runtime_enable(&cldev->dev);
764 
765 	return 0;
766 
767 err_subdev:
768 	v4l2_subdev_cleanup(&csi->subdev);
769 
770 err_entity:
771 	media_entity_cleanup(&csi->subdev.entity);
772 
773 err_ctrl_handler:
774 	v4l2_ctrl_handler_free(&csi->ctrl_handler);
775 	v4l2_async_nf_unregister(&csi->notifier);
776 	v4l2_async_nf_cleanup(&csi->notifier);
777 
778 err_disable:
779 	mei_cldev_disable(cldev);
780 
781 destroy_mutex:
782 	mutex_destroy(&csi->lock);
783 
784 	return ret;
785 }
786 
787 static void mei_csi_remove(struct mei_cl_device *cldev)
788 {
789 	struct mei_csi *csi = mei_cldev_get_drvdata(cldev);
790 
791 	v4l2_async_nf_unregister(&csi->notifier);
792 	v4l2_async_nf_cleanup(&csi->notifier);
793 	v4l2_ctrl_handler_free(&csi->ctrl_handler);
794 	v4l2_async_unregister_subdev(&csi->subdev);
795 	v4l2_subdev_cleanup(&csi->subdev);
796 	media_entity_cleanup(&csi->subdev.entity);
797 
798 	pm_runtime_disable(&cldev->dev);
799 
800 	mutex_destroy(&csi->lock);
801 }
802 
803 #define MEI_CSI_UUID UUID_LE(0x92335FCF, 0x3203, 0x4472, \
804 			     0xAF, 0x93, 0x7b, 0x44, 0x53, 0xAC, 0x29, 0xDA)
805 
806 static const struct mei_cl_device_id mei_csi_tbl[] = {
807 	{ MEI_CSI_DRIVER_NAME, MEI_CSI_UUID, MEI_CL_VERSION_ANY },
808 	{ /* sentinel */ }
809 };
810 MODULE_DEVICE_TABLE(mei, mei_csi_tbl);
811 
812 static struct mei_cl_driver mei_csi_driver = {
813 	.id_table = mei_csi_tbl,
814 	.name = MEI_CSI_DRIVER_NAME,
815 
816 	.probe = mei_csi_probe,
817 	.remove = mei_csi_remove,
818 };
819 
820 module_mei_cl_driver(mei_csi_driver);
821 
822 MODULE_AUTHOR("Wentong Wu <wentong.wu@intel.com>");
823 MODULE_AUTHOR("Zhifeng Wang <zhifeng.wang@intel.com>");
824 MODULE_DESCRIPTION("Device driver for IVSC CSI");
825 MODULE_LICENSE("GPL");
826