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_SINK,
76 	CSI_PAD_SOURCE,
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 	/* lock for v4l2 controls */
128 	struct mutex ctrl_lock;
129 	unsigned int remote_pad;
130 	/* start streaming or not */
131 	int streaming;
132 
133 	struct media_pad pads[CSI_NUM_PADS];
134 	struct v4l2_mbus_framefmt format_mbus[CSI_NUM_PADS];
135 
136 	/* number of data lanes used on the CSI-2 link */
137 	u32 nr_of_lanes;
138 	/* frequency of the CSI-2 link */
139 	u64 link_freq;
140 
141 	/* privacy status */
142 	enum ivsc_privacy_status status;
143 };
144 
145 static const struct v4l2_mbus_framefmt mei_csi_format_mbus_default = {
146 	.width = 1,
147 	.height = 1,
148 	.code = MEDIA_BUS_FMT_Y8_1X8,
149 	.field = V4L2_FIELD_NONE,
150 };
151 
152 static s64 link_freq_menu_items[] = {
153 	MEI_CSI_LINK_FREQ_400MHZ
154 };
155 
notifier_to_csi(struct v4l2_async_notifier * n)156 static inline struct mei_csi *notifier_to_csi(struct v4l2_async_notifier *n)
157 {
158 	return container_of(n, struct mei_csi, notifier);
159 }
160 
sd_to_csi(struct v4l2_subdev * sd)161 static inline struct mei_csi *sd_to_csi(struct v4l2_subdev *sd)
162 {
163 	return container_of(sd, struct mei_csi, subdev);
164 }
165 
ctrl_to_csi(struct v4l2_ctrl * ctrl)166 static inline struct mei_csi *ctrl_to_csi(struct v4l2_ctrl *ctrl)
167 {
168 	return container_of(ctrl->handler, struct mei_csi, ctrl_handler);
169 }
170 
171 /* send a command to firmware and mutex must be held by caller */
mei_csi_send(struct mei_csi * csi,u8 * buf,size_t len)172 static int mei_csi_send(struct mei_csi *csi, u8 *buf, size_t len)
173 {
174 	struct csi_cmd *cmd = (struct csi_cmd *)buf;
175 	int ret;
176 
177 	reinit_completion(&csi->cmd_completion);
178 
179 	ret = mei_cldev_send(csi->cldev, buf, len);
180 	if (ret < 0)
181 		goto out;
182 
183 	ret = wait_for_completion_killable_timeout(&csi->cmd_completion,
184 						   CSI_CMD_TIMEOUT);
185 	if (ret < 0) {
186 		goto out;
187 	} else if (!ret) {
188 		ret = -ETIMEDOUT;
189 		goto out;
190 	}
191 
192 	/* command response status */
193 	ret = csi->cmd_response.status;
194 	if (ret == -1) {
195 		/* notify privacy on instead of reporting error */
196 		ret = 0;
197 		v4l2_ctrl_s_ctrl(csi->privacy_ctrl, 1);
198 	} else if (ret) {
199 		ret = -EINVAL;
200 		goto out;
201 	}
202 
203 	if (csi->cmd_response.cmd_id != cmd->cmd_id)
204 		ret = -EINVAL;
205 
206 out:
207 	return ret;
208 }
209 
210 /* set CSI-2 link ownership */
csi_set_link_owner(struct mei_csi * csi,enum csi_link_owner owner)211 static int csi_set_link_owner(struct mei_csi *csi, enum csi_link_owner owner)
212 {
213 	struct csi_cmd cmd = { 0 };
214 	size_t cmd_size;
215 	int ret;
216 
217 	cmd.cmd_id = CSI_SET_OWNER;
218 	cmd.param.param = owner;
219 	cmd_size = sizeof(cmd.cmd_id) + sizeof(cmd.param.param);
220 
221 	mutex_lock(&csi->lock);
222 
223 	ret = mei_csi_send(csi, (u8 *)&cmd, cmd_size);
224 
225 	mutex_unlock(&csi->lock);
226 
227 	return ret;
228 }
229 
230 /* configure CSI-2 link between host and IVSC */
csi_set_link_cfg(struct mei_csi * csi)231 static int csi_set_link_cfg(struct mei_csi *csi)
232 {
233 	struct csi_cmd cmd = { 0 };
234 	size_t cmd_size;
235 	int ret;
236 
237 	cmd.cmd_id = CSI_SET_CONF;
238 	cmd.param.conf.nr_of_lanes = csi->nr_of_lanes;
239 	cmd.param.conf.link_freq = CSI_LINK_FREQ(csi->link_freq);
240 	cmd_size = sizeof(cmd.cmd_id) + sizeof(cmd.param.conf);
241 
242 	mutex_lock(&csi->lock);
243 
244 	ret = mei_csi_send(csi, (u8 *)&cmd, cmd_size);
245 	/*
246 	 * wait configuration ready if download success. placing
247 	 * delay under mutex is to make sure current command flow
248 	 * completed before starting a possible new one.
249 	 */
250 	if (!ret)
251 		msleep(CSI_FW_READY_DELAY_MS);
252 
253 	mutex_unlock(&csi->lock);
254 
255 	return ret;
256 }
257 
258 /* callback for receive */
mei_csi_rx(struct mei_cl_device * cldev)259 static void mei_csi_rx(struct mei_cl_device *cldev)
260 {
261 	struct mei_csi *csi = mei_cldev_get_drvdata(cldev);
262 	struct csi_notif notif = { 0 };
263 	int ret;
264 
265 	ret = mei_cldev_recv(cldev, (u8 *)&notif, sizeof(notif));
266 	if (ret < 0) {
267 		dev_err(&cldev->dev, "recv error: %d\n", ret);
268 		return;
269 	}
270 
271 	switch (notif.cmd_id) {
272 	case CSI_PRIVACY_NOTIF:
273 		if (notif.cont.cont < CSI_PRIVACY_MAX) {
274 			csi->status = notif.cont.cont;
275 			v4l2_ctrl_s_ctrl(csi->privacy_ctrl, csi->status);
276 		}
277 		break;
278 	case CSI_SET_OWNER:
279 	case CSI_SET_CONF:
280 		memcpy(&csi->cmd_response, &notif, ret);
281 
282 		complete(&csi->cmd_completion);
283 		break;
284 	default:
285 		break;
286 	}
287 }
288 
mei_csi_set_stream(struct v4l2_subdev * sd,int enable)289 static int mei_csi_set_stream(struct v4l2_subdev *sd, int enable)
290 {
291 	struct mei_csi *csi = sd_to_csi(sd);
292 	s64 freq;
293 	int ret;
294 
295 	if (enable && csi->streaming == 0) {
296 		freq = v4l2_get_link_freq(csi->remote->ctrl_handler, 0, 0);
297 		if (freq < 0) {
298 			dev_err(&csi->cldev->dev,
299 				"error %lld, invalid link_freq\n", freq);
300 			ret = freq;
301 			goto err;
302 		}
303 		csi->link_freq = freq;
304 
305 		/* switch CSI-2 link to host */
306 		ret = csi_set_link_owner(csi, CSI_LINK_HOST);
307 		if (ret < 0)
308 			goto err;
309 
310 		/* configure CSI-2 link */
311 		ret = csi_set_link_cfg(csi);
312 		if (ret < 0)
313 			goto err_switch;
314 
315 		ret = v4l2_subdev_call(csi->remote, video, s_stream, 1);
316 		if (ret)
317 			goto err_switch;
318 	} else if (!enable && csi->streaming == 1) {
319 		v4l2_subdev_call(csi->remote, video, s_stream, 0);
320 
321 		/* switch CSI-2 link to IVSC */
322 		ret = csi_set_link_owner(csi, CSI_LINK_IVSC);
323 		if (ret < 0)
324 			dev_warn(&csi->cldev->dev,
325 				 "failed to switch CSI2 link: %d\n", ret);
326 	}
327 
328 	csi->streaming = enable;
329 
330 	return 0;
331 
332 err_switch:
333 	csi_set_link_owner(csi, CSI_LINK_IVSC);
334 
335 err:
336 	return ret;
337 }
338 
339 static struct v4l2_mbus_framefmt *
mei_csi_get_pad_format(struct v4l2_subdev * sd,struct v4l2_subdev_state * sd_state,unsigned int pad,u32 which)340 mei_csi_get_pad_format(struct v4l2_subdev *sd,
341 		       struct v4l2_subdev_state *sd_state,
342 		       unsigned int pad, u32 which)
343 {
344 	struct mei_csi *csi = sd_to_csi(sd);
345 
346 	switch (which) {
347 	case V4L2_SUBDEV_FORMAT_TRY:
348 		return v4l2_subdev_get_try_format(sd, sd_state, pad);
349 	case V4L2_SUBDEV_FORMAT_ACTIVE:
350 		return &csi->format_mbus[pad];
351 	default:
352 		return NULL;
353 	}
354 }
355 
mei_csi_init_cfg(struct v4l2_subdev * sd,struct v4l2_subdev_state * sd_state)356 static int mei_csi_init_cfg(struct v4l2_subdev *sd,
357 			    struct v4l2_subdev_state *sd_state)
358 {
359 	struct v4l2_mbus_framefmt *mbusformat;
360 	struct mei_csi *csi = sd_to_csi(sd);
361 	unsigned int i;
362 
363 	mutex_lock(&csi->lock);
364 
365 	for (i = 0; i < sd->entity.num_pads; i++) {
366 		mbusformat = v4l2_subdev_get_try_format(sd, sd_state, i);
367 		*mbusformat = mei_csi_format_mbus_default;
368 	}
369 
370 	mutex_unlock(&csi->lock);
371 
372 	return 0;
373 }
374 
mei_csi_get_fmt(struct v4l2_subdev * sd,struct v4l2_subdev_state * sd_state,struct v4l2_subdev_format * format)375 static int mei_csi_get_fmt(struct v4l2_subdev *sd,
376 			   struct v4l2_subdev_state *sd_state,
377 			   struct v4l2_subdev_format *format)
378 {
379 	struct v4l2_mbus_framefmt *mbusformat;
380 	struct mei_csi *csi = sd_to_csi(sd);
381 
382 	mutex_lock(&csi->lock);
383 
384 	mbusformat = mei_csi_get_pad_format(sd, sd_state, format->pad,
385 					    format->which);
386 	if (mbusformat)
387 		format->format = *mbusformat;
388 
389 	mutex_unlock(&csi->lock);
390 
391 	return 0;
392 }
393 
mei_csi_set_fmt(struct v4l2_subdev * sd,struct v4l2_subdev_state * sd_state,struct v4l2_subdev_format * format)394 static int mei_csi_set_fmt(struct v4l2_subdev *sd,
395 			   struct v4l2_subdev_state *sd_state,
396 			   struct v4l2_subdev_format *format)
397 {
398 	struct v4l2_mbus_framefmt *source_mbusformat;
399 	struct v4l2_mbus_framefmt *mbusformat;
400 	struct mei_csi *csi = sd_to_csi(sd);
401 	struct media_pad *pad;
402 
403 	mbusformat = mei_csi_get_pad_format(sd, sd_state, format->pad,
404 					    format->which);
405 	if (!mbusformat)
406 		return -EINVAL;
407 
408 	source_mbusformat = mei_csi_get_pad_format(sd, sd_state, CSI_PAD_SOURCE,
409 						   format->which);
410 	if (!source_mbusformat)
411 		return -EINVAL;
412 
413 	v4l_bound_align_image(&format->format.width, 1, 65536, 0,
414 			      &format->format.height, 1, 65536, 0, 0);
415 
416 	switch (format->format.code) {
417 	case MEDIA_BUS_FMT_RGB444_1X12:
418 	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_BE:
419 	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE:
420 	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_BE:
421 	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_LE:
422 	case MEDIA_BUS_FMT_RGB565_1X16:
423 	case MEDIA_BUS_FMT_BGR565_2X8_BE:
424 	case MEDIA_BUS_FMT_BGR565_2X8_LE:
425 	case MEDIA_BUS_FMT_RGB565_2X8_BE:
426 	case MEDIA_BUS_FMT_RGB565_2X8_LE:
427 	case MEDIA_BUS_FMT_RGB666_1X18:
428 	case MEDIA_BUS_FMT_RBG888_1X24:
429 	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
430 	case MEDIA_BUS_FMT_BGR888_1X24:
431 	case MEDIA_BUS_FMT_GBR888_1X24:
432 	case MEDIA_BUS_FMT_RGB888_1X24:
433 	case MEDIA_BUS_FMT_RGB888_2X12_BE:
434 	case MEDIA_BUS_FMT_RGB888_2X12_LE:
435 	case MEDIA_BUS_FMT_ARGB8888_1X32:
436 	case MEDIA_BUS_FMT_RGB888_1X32_PADHI:
437 	case MEDIA_BUS_FMT_RGB101010_1X30:
438 	case MEDIA_BUS_FMT_RGB121212_1X36:
439 	case MEDIA_BUS_FMT_RGB161616_1X48:
440 	case MEDIA_BUS_FMT_Y8_1X8:
441 	case MEDIA_BUS_FMT_UV8_1X8:
442 	case MEDIA_BUS_FMT_UYVY8_1_5X8:
443 	case MEDIA_BUS_FMT_VYUY8_1_5X8:
444 	case MEDIA_BUS_FMT_YUYV8_1_5X8:
445 	case MEDIA_BUS_FMT_YVYU8_1_5X8:
446 	case MEDIA_BUS_FMT_UYVY8_2X8:
447 	case MEDIA_BUS_FMT_VYUY8_2X8:
448 	case MEDIA_BUS_FMT_YUYV8_2X8:
449 	case MEDIA_BUS_FMT_YVYU8_2X8:
450 	case MEDIA_BUS_FMT_Y10_1X10:
451 	case MEDIA_BUS_FMT_UYVY10_2X10:
452 	case MEDIA_BUS_FMT_VYUY10_2X10:
453 	case MEDIA_BUS_FMT_YUYV10_2X10:
454 	case MEDIA_BUS_FMT_YVYU10_2X10:
455 	case MEDIA_BUS_FMT_Y12_1X12:
456 	case MEDIA_BUS_FMT_UYVY12_2X12:
457 	case MEDIA_BUS_FMT_VYUY12_2X12:
458 	case MEDIA_BUS_FMT_YUYV12_2X12:
459 	case MEDIA_BUS_FMT_YVYU12_2X12:
460 	case MEDIA_BUS_FMT_UYVY8_1X16:
461 	case MEDIA_BUS_FMT_VYUY8_1X16:
462 	case MEDIA_BUS_FMT_YUYV8_1X16:
463 	case MEDIA_BUS_FMT_YVYU8_1X16:
464 	case MEDIA_BUS_FMT_YDYUYDYV8_1X16:
465 	case MEDIA_BUS_FMT_UYVY10_1X20:
466 	case MEDIA_BUS_FMT_VYUY10_1X20:
467 	case MEDIA_BUS_FMT_YUYV10_1X20:
468 	case MEDIA_BUS_FMT_YVYU10_1X20:
469 	case MEDIA_BUS_FMT_VUY8_1X24:
470 	case MEDIA_BUS_FMT_YUV8_1X24:
471 	case MEDIA_BUS_FMT_UYYVYY8_0_5X24:
472 	case MEDIA_BUS_FMT_UYVY12_1X24:
473 	case MEDIA_BUS_FMT_VYUY12_1X24:
474 	case MEDIA_BUS_FMT_YUYV12_1X24:
475 	case MEDIA_BUS_FMT_YVYU12_1X24:
476 	case MEDIA_BUS_FMT_YUV10_1X30:
477 	case MEDIA_BUS_FMT_UYYVYY10_0_5X30:
478 	case MEDIA_BUS_FMT_AYUV8_1X32:
479 	case MEDIA_BUS_FMT_UYYVYY12_0_5X36:
480 	case MEDIA_BUS_FMT_YUV12_1X36:
481 	case MEDIA_BUS_FMT_YUV16_1X48:
482 	case MEDIA_BUS_FMT_UYYVYY16_0_5X48:
483 	case MEDIA_BUS_FMT_JPEG_1X8:
484 	case MEDIA_BUS_FMT_AHSV8888_1X32:
485 	case MEDIA_BUS_FMT_SBGGR8_1X8:
486 	case MEDIA_BUS_FMT_SGBRG8_1X8:
487 	case MEDIA_BUS_FMT_SGRBG8_1X8:
488 	case MEDIA_BUS_FMT_SRGGB8_1X8:
489 	case MEDIA_BUS_FMT_SBGGR10_1X10:
490 	case MEDIA_BUS_FMT_SGBRG10_1X10:
491 	case MEDIA_BUS_FMT_SGRBG10_1X10:
492 	case MEDIA_BUS_FMT_SRGGB10_1X10:
493 	case MEDIA_BUS_FMT_SBGGR12_1X12:
494 	case MEDIA_BUS_FMT_SGBRG12_1X12:
495 	case MEDIA_BUS_FMT_SGRBG12_1X12:
496 	case MEDIA_BUS_FMT_SRGGB12_1X12:
497 	case MEDIA_BUS_FMT_SBGGR14_1X14:
498 	case MEDIA_BUS_FMT_SGBRG14_1X14:
499 	case MEDIA_BUS_FMT_SGRBG14_1X14:
500 	case MEDIA_BUS_FMT_SRGGB14_1X14:
501 	case MEDIA_BUS_FMT_SBGGR16_1X16:
502 	case MEDIA_BUS_FMT_SGBRG16_1X16:
503 	case MEDIA_BUS_FMT_SGRBG16_1X16:
504 	case MEDIA_BUS_FMT_SRGGB16_1X16:
505 		break;
506 	default:
507 		format->format.code = MEDIA_BUS_FMT_Y8_1X8;
508 		break;
509 	}
510 
511 	if (format->format.field == V4L2_FIELD_ANY)
512 		format->format.field = V4L2_FIELD_NONE;
513 
514 	mutex_lock(&csi->lock);
515 
516 	pad = &csi->pads[format->pad];
517 	if (pad->flags & MEDIA_PAD_FL_SOURCE)
518 		format->format = csi->format_mbus[CSI_PAD_SINK];
519 
520 	*mbusformat = format->format;
521 
522 	if (pad->flags & MEDIA_PAD_FL_SINK)
523 		*source_mbusformat = format->format;
524 
525 	mutex_unlock(&csi->lock);
526 
527 	return 0;
528 }
529 
mei_csi_g_volatile_ctrl(struct v4l2_ctrl * ctrl)530 static int mei_csi_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
531 {
532 	struct mei_csi *csi = ctrl_to_csi(ctrl);
533 	s64 freq;
534 
535 	if (ctrl->id == V4L2_CID_LINK_FREQ) {
536 		if (!csi->remote)
537 			return -EINVAL;
538 
539 		freq = v4l2_get_link_freq(csi->remote->ctrl_handler, 0, 0);
540 		if (freq < 0) {
541 			dev_err(&csi->cldev->dev,
542 				"error %lld, invalid link_freq\n", freq);
543 			return -EINVAL;
544 		}
545 
546 		link_freq_menu_items[0] = freq;
547 		ctrl->val = 0;
548 
549 		return 0;
550 	}
551 
552 	return -EINVAL;
553 }
554 
555 static const struct v4l2_ctrl_ops mei_csi_ctrl_ops = {
556 	.g_volatile_ctrl = mei_csi_g_volatile_ctrl,
557 };
558 
559 static const struct v4l2_subdev_video_ops mei_csi_video_ops = {
560 	.s_stream = mei_csi_set_stream,
561 };
562 
563 static const struct v4l2_subdev_pad_ops mei_csi_pad_ops = {
564 	.init_cfg = mei_csi_init_cfg,
565 	.get_fmt = mei_csi_get_fmt,
566 	.set_fmt = mei_csi_set_fmt,
567 };
568 
569 static const struct v4l2_subdev_ops mei_csi_subdev_ops = {
570 	.video = &mei_csi_video_ops,
571 	.pad = &mei_csi_pad_ops,
572 };
573 
574 static const struct media_entity_operations mei_csi_entity_ops = {
575 	.link_validate = v4l2_subdev_link_validate,
576 };
577 
mei_csi_notify_bound(struct v4l2_async_notifier * notifier,struct v4l2_subdev * subdev,struct v4l2_async_connection * asd)578 static int mei_csi_notify_bound(struct v4l2_async_notifier *notifier,
579 				struct v4l2_subdev *subdev,
580 				struct v4l2_async_connection *asd)
581 {
582 	struct mei_csi *csi = notifier_to_csi(notifier);
583 	int pad;
584 
585 	pad = media_entity_get_fwnode_pad(&subdev->entity, asd->match.fwnode,
586 					  MEDIA_PAD_FL_SOURCE);
587 	if (pad < 0)
588 		return pad;
589 
590 	csi->remote = subdev;
591 	csi->remote_pad = pad;
592 
593 	return media_create_pad_link(&subdev->entity, pad,
594 				     &csi->subdev.entity, CSI_PAD_SINK,
595 				     MEDIA_LNK_FL_ENABLED |
596 				     MEDIA_LNK_FL_IMMUTABLE);
597 }
598 
mei_csi_notify_unbind(struct v4l2_async_notifier * notifier,struct v4l2_subdev * subdev,struct v4l2_async_connection * asd)599 static void mei_csi_notify_unbind(struct v4l2_async_notifier *notifier,
600 				  struct v4l2_subdev *subdev,
601 				  struct v4l2_async_connection *asd)
602 {
603 	struct mei_csi *csi = notifier_to_csi(notifier);
604 
605 	csi->remote = NULL;
606 }
607 
608 static const struct v4l2_async_notifier_operations mei_csi_notify_ops = {
609 	.bound = mei_csi_notify_bound,
610 	.unbind = mei_csi_notify_unbind,
611 };
612 
mei_csi_init_controls(struct mei_csi * csi)613 static int mei_csi_init_controls(struct mei_csi *csi)
614 {
615 	u32 max;
616 	int ret;
617 
618 	mutex_init(&csi->ctrl_lock);
619 
620 	ret = v4l2_ctrl_handler_init(&csi->ctrl_handler, 2);
621 	if (ret)
622 		return ret;
623 
624 	csi->ctrl_handler.lock = &csi->ctrl_lock;
625 
626 	max = ARRAY_SIZE(link_freq_menu_items) - 1;
627 	csi->freq_ctrl = v4l2_ctrl_new_int_menu(&csi->ctrl_handler,
628 						&mei_csi_ctrl_ops,
629 						V4L2_CID_LINK_FREQ,
630 						max,
631 						0,
632 						link_freq_menu_items);
633 	if (csi->freq_ctrl)
634 		csi->freq_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY |
635 					 V4L2_CTRL_FLAG_VOLATILE;
636 
637 	csi->privacy_ctrl = v4l2_ctrl_new_std(&csi->ctrl_handler, NULL,
638 					      V4L2_CID_PRIVACY, 0, 1, 1, 0);
639 	if (csi->privacy_ctrl)
640 		csi->privacy_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
641 
642 	if (csi->ctrl_handler.error)
643 		return csi->ctrl_handler.error;
644 
645 	csi->subdev.ctrl_handler = &csi->ctrl_handler;
646 
647 	return 0;
648 }
649 
mei_csi_parse_firmware(struct mei_csi * csi)650 static int mei_csi_parse_firmware(struct mei_csi *csi)
651 {
652 	struct v4l2_fwnode_endpoint v4l2_ep = {
653 		.bus_type = V4L2_MBUS_CSI2_DPHY,
654 	};
655 	struct device *dev = &csi->cldev->dev;
656 	struct v4l2_async_connection *asd;
657 	struct fwnode_handle *fwnode;
658 	struct fwnode_handle *ep;
659 	int ret;
660 
661 	ep = fwnode_graph_get_endpoint_by_id(dev_fwnode(dev), 0, 0, 0);
662 	if (!ep) {
663 		dev_err(dev, "not connected to subdevice\n");
664 		return -EINVAL;
665 	}
666 
667 	ret = v4l2_fwnode_endpoint_parse(ep, &v4l2_ep);
668 	if (ret) {
669 		dev_err(dev, "could not parse v4l2 endpoint\n");
670 		fwnode_handle_put(ep);
671 		return -EINVAL;
672 	}
673 
674 	fwnode = fwnode_graph_get_remote_endpoint(ep);
675 	fwnode_handle_put(ep);
676 
677 	v4l2_async_subdev_nf_init(&csi->notifier, &csi->subdev);
678 	csi->notifier.ops = &mei_csi_notify_ops;
679 
680 	asd = v4l2_async_nf_add_fwnode(&csi->notifier, fwnode,
681 				       struct v4l2_async_connection);
682 	if (IS_ERR(asd)) {
683 		fwnode_handle_put(fwnode);
684 		return PTR_ERR(asd);
685 	}
686 
687 	ret = v4l2_fwnode_endpoint_alloc_parse(fwnode, &v4l2_ep);
688 	fwnode_handle_put(fwnode);
689 	if (ret)
690 		return ret;
691 	csi->nr_of_lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
692 
693 	ret = v4l2_async_nf_register(&csi->notifier);
694 	if (ret)
695 		v4l2_async_nf_cleanup(&csi->notifier);
696 
697 	v4l2_fwnode_endpoint_free(&v4l2_ep);
698 
699 	return ret;
700 }
701 
mei_csi_probe(struct mei_cl_device * cldev,const struct mei_cl_device_id * id)702 static int mei_csi_probe(struct mei_cl_device *cldev,
703 			 const struct mei_cl_device_id *id)
704 {
705 	struct device *dev = &cldev->dev;
706 	struct mei_csi *csi;
707 	int ret;
708 
709 	if (!dev_fwnode(dev))
710 		return -EPROBE_DEFER;
711 
712 	csi = devm_kzalloc(dev, sizeof(struct mei_csi), GFP_KERNEL);
713 	if (!csi)
714 		return -ENOMEM;
715 
716 	csi->cldev = cldev;
717 	mutex_init(&csi->lock);
718 	init_completion(&csi->cmd_completion);
719 
720 	mei_cldev_set_drvdata(cldev, csi);
721 
722 	ret = mei_cldev_enable(cldev);
723 	if (ret < 0) {
724 		dev_err(dev, "mei_cldev_enable failed: %d\n", ret);
725 		goto destroy_mutex;
726 	}
727 
728 	ret = mei_cldev_register_rx_cb(cldev, mei_csi_rx);
729 	if (ret) {
730 		dev_err(dev, "event cb registration failed: %d\n", ret);
731 		goto err_disable;
732 	}
733 
734 	ret = mei_csi_parse_firmware(csi);
735 	if (ret)
736 		goto err_disable;
737 
738 	csi->subdev.dev = &cldev->dev;
739 	v4l2_subdev_init(&csi->subdev, &mei_csi_subdev_ops);
740 	v4l2_set_subdevdata(&csi->subdev, csi);
741 	csi->subdev.flags = V4L2_SUBDEV_FL_HAS_DEVNODE |
742 			    V4L2_SUBDEV_FL_HAS_EVENTS;
743 	csi->subdev.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
744 	csi->subdev.entity.ops = &mei_csi_entity_ops;
745 
746 	snprintf(csi->subdev.name, sizeof(csi->subdev.name),
747 		 MEI_CSI_ENTITY_NAME);
748 
749 	ret = mei_csi_init_controls(csi);
750 	if (ret)
751 		goto err_ctrl_handler;
752 
753 	csi->format_mbus[CSI_PAD_SOURCE] = mei_csi_format_mbus_default;
754 	csi->format_mbus[CSI_PAD_SINK] = mei_csi_format_mbus_default;
755 
756 	csi->pads[CSI_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
757 	csi->pads[CSI_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
758 	ret = media_entity_pads_init(&csi->subdev.entity, CSI_NUM_PADS,
759 				     csi->pads);
760 	if (ret)
761 		goto err_ctrl_handler;
762 
763 	ret = v4l2_subdev_init_finalize(&csi->subdev);
764 	if (ret < 0)
765 		goto err_entity;
766 
767 	ret = v4l2_async_register_subdev(&csi->subdev);
768 	if (ret < 0)
769 		goto err_subdev;
770 
771 	pm_runtime_enable(&cldev->dev);
772 
773 	return 0;
774 
775 err_subdev:
776 	v4l2_subdev_cleanup(&csi->subdev);
777 
778 err_entity:
779 	media_entity_cleanup(&csi->subdev.entity);
780 
781 err_ctrl_handler:
782 	v4l2_ctrl_handler_free(&csi->ctrl_handler);
783 	mutex_destroy(&csi->ctrl_lock);
784 	v4l2_async_nf_unregister(&csi->notifier);
785 	v4l2_async_nf_cleanup(&csi->notifier);
786 
787 err_disable:
788 	mei_cldev_disable(cldev);
789 
790 destroy_mutex:
791 	mutex_destroy(&csi->lock);
792 
793 	return ret;
794 }
795 
mei_csi_remove(struct mei_cl_device * cldev)796 static void mei_csi_remove(struct mei_cl_device *cldev)
797 {
798 	struct mei_csi *csi = mei_cldev_get_drvdata(cldev);
799 
800 	v4l2_async_nf_unregister(&csi->notifier);
801 	v4l2_async_nf_cleanup(&csi->notifier);
802 	v4l2_ctrl_handler_free(&csi->ctrl_handler);
803 	mutex_destroy(&csi->ctrl_lock);
804 	v4l2_async_unregister_subdev(&csi->subdev);
805 	v4l2_subdev_cleanup(&csi->subdev);
806 	media_entity_cleanup(&csi->subdev.entity);
807 
808 	pm_runtime_disable(&cldev->dev);
809 
810 	mutex_destroy(&csi->lock);
811 }
812 
813 #define MEI_CSI_UUID UUID_LE(0x92335FCF, 0x3203, 0x4472, \
814 			     0xAF, 0x93, 0x7b, 0x44, 0x53, 0xAC, 0x29, 0xDA)
815 
816 static const struct mei_cl_device_id mei_csi_tbl[] = {
817 	{ MEI_CSI_DRIVER_NAME, MEI_CSI_UUID, MEI_CL_VERSION_ANY },
818 	{ /* sentinel */ }
819 };
820 MODULE_DEVICE_TABLE(mei, mei_csi_tbl);
821 
822 static struct mei_cl_driver mei_csi_driver = {
823 	.id_table = mei_csi_tbl,
824 	.name = MEI_CSI_DRIVER_NAME,
825 
826 	.probe = mei_csi_probe,
827 	.remove = mei_csi_remove,
828 };
829 
830 module_mei_cl_driver(mei_csi_driver);
831 
832 MODULE_AUTHOR("Wentong Wu <wentong.wu@intel.com>");
833 MODULE_AUTHOR("Zhifeng Wang <zhifeng.wang@intel.com>");
834 MODULE_DESCRIPTION("Device driver for IVSC CSI");
835 MODULE_LICENSE("GPL");
836