1 /*
2  * video stream multiplexer controlled via mux control
3  *
4  * Copyright (C) 2013 Pengutronix, Sascha Hauer <kernel@pengutronix.de>
5  * Copyright (C) 2016-2017 Pengutronix, Philipp Zabel <kernel@pengutronix.de>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * as published by the Free Software Foundation; either version 2
10  * of the License, or (at your option) any later version.
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #include <linux/err.h>
18 #include <linux/module.h>
19 #include <linux/mutex.h>
20 #include <linux/mux/consumer.h>
21 #include <linux/of.h>
22 #include <linux/of_graph.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <media/v4l2-async.h>
26 #include <media/v4l2-device.h>
27 #include <media/v4l2-fwnode.h>
28 #include <media/v4l2-subdev.h>
29 
30 struct video_mux {
31 	struct v4l2_subdev subdev;
32 	struct media_pad *pads;
33 	struct v4l2_mbus_framefmt *format_mbus;
34 	struct mux_control *mux;
35 	struct mutex lock;
36 	int active;
37 };
38 
39 static const struct v4l2_mbus_framefmt video_mux_format_mbus_default = {
40 	.width = 1,
41 	.height = 1,
42 	.code = MEDIA_BUS_FMT_Y8_1X8,
43 	.field = V4L2_FIELD_NONE,
44 };
45 
46 static inline struct video_mux *v4l2_subdev_to_video_mux(struct v4l2_subdev *sd)
47 {
48 	return container_of(sd, struct video_mux, subdev);
49 }
50 
51 static int video_mux_link_setup(struct media_entity *entity,
52 				const struct media_pad *local,
53 				const struct media_pad *remote, u32 flags)
54 {
55 	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
56 	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
57 	u16 source_pad = entity->num_pads - 1;
58 	int ret = 0;
59 
60 	/*
61 	 * The mux state is determined by the enabled sink pad link.
62 	 * Enabling or disabling the source pad link has no effect.
63 	 */
64 	if (local->flags & MEDIA_PAD_FL_SOURCE)
65 		return 0;
66 
67 	dev_dbg(sd->dev, "link setup '%s':%d->'%s':%d[%d]",
68 		remote->entity->name, remote->index, local->entity->name,
69 		local->index, flags & MEDIA_LNK_FL_ENABLED);
70 
71 	mutex_lock(&vmux->lock);
72 
73 	if (flags & MEDIA_LNK_FL_ENABLED) {
74 		if (vmux->active == local->index)
75 			goto out;
76 
77 		if (vmux->active >= 0) {
78 			ret = -EBUSY;
79 			goto out;
80 		}
81 
82 		dev_dbg(sd->dev, "setting %d active\n", local->index);
83 		ret = mux_control_try_select(vmux->mux, local->index);
84 		if (ret < 0)
85 			goto out;
86 		vmux->active = local->index;
87 
88 		/* Propagate the active format to the source */
89 		vmux->format_mbus[source_pad] = vmux->format_mbus[vmux->active];
90 	} else {
91 		if (vmux->active != local->index)
92 			goto out;
93 
94 		dev_dbg(sd->dev, "going inactive\n");
95 		mux_control_deselect(vmux->mux);
96 		vmux->active = -1;
97 	}
98 
99 out:
100 	mutex_unlock(&vmux->lock);
101 	return ret;
102 }
103 
104 static const struct media_entity_operations video_mux_ops = {
105 	.link_setup = video_mux_link_setup,
106 	.link_validate = v4l2_subdev_link_validate,
107 };
108 
109 static int video_mux_s_stream(struct v4l2_subdev *sd, int enable)
110 {
111 	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
112 	struct v4l2_subdev *upstream_sd;
113 	struct media_pad *pad;
114 
115 	if (vmux->active == -1) {
116 		dev_err(sd->dev, "Can not start streaming on inactive mux\n");
117 		return -EINVAL;
118 	}
119 
120 	pad = media_entity_remote_pad(&sd->entity.pads[vmux->active]);
121 	if (!pad) {
122 		dev_err(sd->dev, "Failed to find remote source pad\n");
123 		return -ENOLINK;
124 	}
125 
126 	if (!is_media_entity_v4l2_subdev(pad->entity)) {
127 		dev_err(sd->dev, "Upstream entity is not a v4l2 subdev\n");
128 		return -ENODEV;
129 	}
130 
131 	upstream_sd = media_entity_to_v4l2_subdev(pad->entity);
132 
133 	return v4l2_subdev_call(upstream_sd, video, s_stream, enable);
134 }
135 
136 static const struct v4l2_subdev_video_ops video_mux_subdev_video_ops = {
137 	.s_stream = video_mux_s_stream,
138 };
139 
140 static struct v4l2_mbus_framefmt *
141 __video_mux_get_pad_format(struct v4l2_subdev *sd,
142 			   struct v4l2_subdev_pad_config *cfg,
143 			   unsigned int pad, u32 which)
144 {
145 	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
146 
147 	switch (which) {
148 	case V4L2_SUBDEV_FORMAT_TRY:
149 		return v4l2_subdev_get_try_format(sd, cfg, pad);
150 	case V4L2_SUBDEV_FORMAT_ACTIVE:
151 		return &vmux->format_mbus[pad];
152 	default:
153 		return NULL;
154 	}
155 }
156 
157 static int video_mux_get_format(struct v4l2_subdev *sd,
158 			    struct v4l2_subdev_pad_config *cfg,
159 			    struct v4l2_subdev_format *sdformat)
160 {
161 	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
162 
163 	mutex_lock(&vmux->lock);
164 
165 	sdformat->format = *__video_mux_get_pad_format(sd, cfg, sdformat->pad,
166 						       sdformat->which);
167 
168 	mutex_unlock(&vmux->lock);
169 
170 	return 0;
171 }
172 
173 static int video_mux_set_format(struct v4l2_subdev *sd,
174 			    struct v4l2_subdev_pad_config *cfg,
175 			    struct v4l2_subdev_format *sdformat)
176 {
177 	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
178 	struct v4l2_mbus_framefmt *mbusformat, *source_mbusformat;
179 	struct media_pad *pad = &vmux->pads[sdformat->pad];
180 	u16 source_pad = sd->entity.num_pads - 1;
181 
182 	mbusformat = __video_mux_get_pad_format(sd, cfg, sdformat->pad,
183 					    sdformat->which);
184 	if (!mbusformat)
185 		return -EINVAL;
186 
187 	source_mbusformat = __video_mux_get_pad_format(sd, cfg, source_pad,
188 						       sdformat->which);
189 	if (!source_mbusformat)
190 		return -EINVAL;
191 
192 	/* No size limitations except V4L2 compliance requirements */
193 	v4l_bound_align_image(&sdformat->format.width, 1, 65536, 0,
194 			      &sdformat->format.height, 1, 65536, 0, 0);
195 
196 	/* All formats except LVDS and vendor specific formats are acceptable */
197 	switch (sdformat->format.code) {
198 	case MEDIA_BUS_FMT_RGB444_1X12:
199 	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_BE:
200 	case MEDIA_BUS_FMT_RGB444_2X8_PADHI_LE:
201 	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_BE:
202 	case MEDIA_BUS_FMT_RGB555_2X8_PADHI_LE:
203 	case MEDIA_BUS_FMT_RGB565_1X16:
204 	case MEDIA_BUS_FMT_BGR565_2X8_BE:
205 	case MEDIA_BUS_FMT_BGR565_2X8_LE:
206 	case MEDIA_BUS_FMT_RGB565_2X8_BE:
207 	case MEDIA_BUS_FMT_RGB565_2X8_LE:
208 	case MEDIA_BUS_FMT_RGB666_1X18:
209 	case MEDIA_BUS_FMT_RBG888_1X24:
210 	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
211 	case MEDIA_BUS_FMT_BGR888_1X24:
212 	case MEDIA_BUS_FMT_GBR888_1X24:
213 	case MEDIA_BUS_FMT_RGB888_1X24:
214 	case MEDIA_BUS_FMT_RGB888_2X12_BE:
215 	case MEDIA_BUS_FMT_RGB888_2X12_LE:
216 	case MEDIA_BUS_FMT_ARGB8888_1X32:
217 	case MEDIA_BUS_FMT_RGB888_1X32_PADHI:
218 	case MEDIA_BUS_FMT_RGB101010_1X30:
219 	case MEDIA_BUS_FMT_RGB121212_1X36:
220 	case MEDIA_BUS_FMT_RGB161616_1X48:
221 	case MEDIA_BUS_FMT_Y8_1X8:
222 	case MEDIA_BUS_FMT_UV8_1X8:
223 	case MEDIA_BUS_FMT_UYVY8_1_5X8:
224 	case MEDIA_BUS_FMT_VYUY8_1_5X8:
225 	case MEDIA_BUS_FMT_YUYV8_1_5X8:
226 	case MEDIA_BUS_FMT_YVYU8_1_5X8:
227 	case MEDIA_BUS_FMT_UYVY8_2X8:
228 	case MEDIA_BUS_FMT_VYUY8_2X8:
229 	case MEDIA_BUS_FMT_YUYV8_2X8:
230 	case MEDIA_BUS_FMT_YVYU8_2X8:
231 	case MEDIA_BUS_FMT_Y10_1X10:
232 	case MEDIA_BUS_FMT_UYVY10_2X10:
233 	case MEDIA_BUS_FMT_VYUY10_2X10:
234 	case MEDIA_BUS_FMT_YUYV10_2X10:
235 	case MEDIA_BUS_FMT_YVYU10_2X10:
236 	case MEDIA_BUS_FMT_Y12_1X12:
237 	case MEDIA_BUS_FMT_UYVY12_2X12:
238 	case MEDIA_BUS_FMT_VYUY12_2X12:
239 	case MEDIA_BUS_FMT_YUYV12_2X12:
240 	case MEDIA_BUS_FMT_YVYU12_2X12:
241 	case MEDIA_BUS_FMT_UYVY8_1X16:
242 	case MEDIA_BUS_FMT_VYUY8_1X16:
243 	case MEDIA_BUS_FMT_YUYV8_1X16:
244 	case MEDIA_BUS_FMT_YVYU8_1X16:
245 	case MEDIA_BUS_FMT_YDYUYDYV8_1X16:
246 	case MEDIA_BUS_FMT_UYVY10_1X20:
247 	case MEDIA_BUS_FMT_VYUY10_1X20:
248 	case MEDIA_BUS_FMT_YUYV10_1X20:
249 	case MEDIA_BUS_FMT_YVYU10_1X20:
250 	case MEDIA_BUS_FMT_VUY8_1X24:
251 	case MEDIA_BUS_FMT_YUV8_1X24:
252 	case MEDIA_BUS_FMT_UYYVYY8_0_5X24:
253 	case MEDIA_BUS_FMT_UYVY12_1X24:
254 	case MEDIA_BUS_FMT_VYUY12_1X24:
255 	case MEDIA_BUS_FMT_YUYV12_1X24:
256 	case MEDIA_BUS_FMT_YVYU12_1X24:
257 	case MEDIA_BUS_FMT_YUV10_1X30:
258 	case MEDIA_BUS_FMT_UYYVYY10_0_5X30:
259 	case MEDIA_BUS_FMT_AYUV8_1X32:
260 	case MEDIA_BUS_FMT_UYYVYY12_0_5X36:
261 	case MEDIA_BUS_FMT_YUV12_1X36:
262 	case MEDIA_BUS_FMT_YUV16_1X48:
263 	case MEDIA_BUS_FMT_UYYVYY16_0_5X48:
264 	case MEDIA_BUS_FMT_JPEG_1X8:
265 	case MEDIA_BUS_FMT_AHSV8888_1X32:
266 	case MEDIA_BUS_FMT_SBGGR8_1X8:
267 	case MEDIA_BUS_FMT_SGBRG8_1X8:
268 	case MEDIA_BUS_FMT_SGRBG8_1X8:
269 	case MEDIA_BUS_FMT_SRGGB8_1X8:
270 	case MEDIA_BUS_FMT_SBGGR10_1X10:
271 	case MEDIA_BUS_FMT_SGBRG10_1X10:
272 	case MEDIA_BUS_FMT_SGRBG10_1X10:
273 	case MEDIA_BUS_FMT_SRGGB10_1X10:
274 	case MEDIA_BUS_FMT_SBGGR12_1X12:
275 	case MEDIA_BUS_FMT_SGBRG12_1X12:
276 	case MEDIA_BUS_FMT_SGRBG12_1X12:
277 	case MEDIA_BUS_FMT_SRGGB12_1X12:
278 	case MEDIA_BUS_FMT_SBGGR14_1X14:
279 	case MEDIA_BUS_FMT_SGBRG14_1X14:
280 	case MEDIA_BUS_FMT_SGRBG14_1X14:
281 	case MEDIA_BUS_FMT_SRGGB14_1X14:
282 	case MEDIA_BUS_FMT_SBGGR16_1X16:
283 	case MEDIA_BUS_FMT_SGBRG16_1X16:
284 	case MEDIA_BUS_FMT_SGRBG16_1X16:
285 	case MEDIA_BUS_FMT_SRGGB16_1X16:
286 		break;
287 	default:
288 		sdformat->format.code = MEDIA_BUS_FMT_Y8_1X8;
289 		break;
290 	}
291 	if (sdformat->format.field == V4L2_FIELD_ANY)
292 		sdformat->format.field = V4L2_FIELD_NONE;
293 
294 	mutex_lock(&vmux->lock);
295 
296 	/* Source pad mirrors active sink pad, no limitations on sink pads */
297 	if ((pad->flags & MEDIA_PAD_FL_SOURCE) && vmux->active >= 0)
298 		sdformat->format = vmux->format_mbus[vmux->active];
299 
300 	*mbusformat = sdformat->format;
301 
302 	/* Propagate the format from an active sink to source */
303 	if ((pad->flags & MEDIA_PAD_FL_SINK) && (pad->index == vmux->active))
304 		*source_mbusformat = sdformat->format;
305 
306 	mutex_unlock(&vmux->lock);
307 
308 	return 0;
309 }
310 
311 static int video_mux_init_cfg(struct v4l2_subdev *sd,
312 			      struct v4l2_subdev_pad_config *cfg)
313 {
314 	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
315 	struct v4l2_mbus_framefmt *mbusformat;
316 	unsigned int i;
317 
318 	mutex_lock(&vmux->lock);
319 
320 	for (i = 0; i < sd->entity.num_pads; i++) {
321 		mbusformat = v4l2_subdev_get_try_format(sd, cfg, i);
322 		*mbusformat = video_mux_format_mbus_default;
323 	}
324 
325 	mutex_unlock(&vmux->lock);
326 
327 	return 0;
328 }
329 
330 static const struct v4l2_subdev_pad_ops video_mux_pad_ops = {
331 	.init_cfg = video_mux_init_cfg,
332 	.get_fmt = video_mux_get_format,
333 	.set_fmt = video_mux_set_format,
334 };
335 
336 static const struct v4l2_subdev_ops video_mux_subdev_ops = {
337 	.pad = &video_mux_pad_ops,
338 	.video = &video_mux_subdev_video_ops,
339 };
340 
341 static int video_mux_parse_endpoint(struct device *dev,
342 				    struct v4l2_fwnode_endpoint *vep,
343 				    struct v4l2_async_subdev *asd)
344 {
345 	/*
346 	 * it's not an error if remote is missing on a video-mux
347 	 * input port, return -ENOTCONN to skip this endpoint with
348 	 * no error.
349 	 */
350 	return fwnode_device_is_available(asd->match.fwnode) ? 0 : -ENOTCONN;
351 }
352 
353 static int video_mux_async_register(struct video_mux *vmux,
354 				    unsigned int num_input_pads)
355 {
356 	unsigned int i, *ports;
357 	int ret;
358 
359 	ports = kcalloc(num_input_pads, sizeof(*ports), GFP_KERNEL);
360 	if (!ports)
361 		return -ENOMEM;
362 	for (i = 0; i < num_input_pads; i++)
363 		ports[i] = i;
364 
365 	ret = v4l2_async_register_fwnode_subdev(
366 		&vmux->subdev, sizeof(struct v4l2_async_subdev),
367 		ports, num_input_pads, video_mux_parse_endpoint);
368 
369 	kfree(ports);
370 	return ret;
371 }
372 
373 static int video_mux_probe(struct platform_device *pdev)
374 {
375 	struct device_node *np = pdev->dev.of_node;
376 	struct device *dev = &pdev->dev;
377 	struct device_node *ep;
378 	struct video_mux *vmux;
379 	unsigned int num_pads = 0;
380 	unsigned int i;
381 	int ret;
382 
383 	vmux = devm_kzalloc(dev, sizeof(*vmux), GFP_KERNEL);
384 	if (!vmux)
385 		return -ENOMEM;
386 
387 	platform_set_drvdata(pdev, vmux);
388 
389 	v4l2_subdev_init(&vmux->subdev, &video_mux_subdev_ops);
390 	snprintf(vmux->subdev.name, sizeof(vmux->subdev.name), "%pOFn", np);
391 	vmux->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
392 	vmux->subdev.dev = dev;
393 
394 	/*
395 	 * The largest numbered port is the output port. It determines
396 	 * total number of pads.
397 	 */
398 	for_each_endpoint_of_node(np, ep) {
399 		struct of_endpoint endpoint;
400 
401 		of_graph_parse_endpoint(ep, &endpoint);
402 		num_pads = max(num_pads, endpoint.port + 1);
403 	}
404 
405 	if (num_pads < 2) {
406 		dev_err(dev, "Not enough ports %d\n", num_pads);
407 		return -EINVAL;
408 	}
409 
410 	vmux->mux = devm_mux_control_get(dev, NULL);
411 	if (IS_ERR(vmux->mux)) {
412 		ret = PTR_ERR(vmux->mux);
413 		if (ret != -EPROBE_DEFER)
414 			dev_err(dev, "Failed to get mux: %d\n", ret);
415 		return ret;
416 	}
417 
418 	mutex_init(&vmux->lock);
419 	vmux->active = -1;
420 	vmux->pads = devm_kcalloc(dev, num_pads, sizeof(*vmux->pads),
421 				  GFP_KERNEL);
422 	vmux->format_mbus = devm_kcalloc(dev, num_pads,
423 					 sizeof(*vmux->format_mbus),
424 					 GFP_KERNEL);
425 
426 	for (i = 0; i < num_pads; i++) {
427 		vmux->pads[i].flags = (i < num_pads - 1) ? MEDIA_PAD_FL_SINK
428 							 : MEDIA_PAD_FL_SOURCE;
429 		vmux->format_mbus[i] = video_mux_format_mbus_default;
430 	}
431 
432 	vmux->subdev.entity.function = MEDIA_ENT_F_VID_MUX;
433 	ret = media_entity_pads_init(&vmux->subdev.entity, num_pads,
434 				     vmux->pads);
435 	if (ret < 0)
436 		return ret;
437 
438 	vmux->subdev.entity.ops = &video_mux_ops;
439 
440 	return video_mux_async_register(vmux, num_pads - 1);
441 }
442 
443 static int video_mux_remove(struct platform_device *pdev)
444 {
445 	struct video_mux *vmux = platform_get_drvdata(pdev);
446 	struct v4l2_subdev *sd = &vmux->subdev;
447 
448 	v4l2_async_unregister_subdev(sd);
449 	media_entity_cleanup(&sd->entity);
450 
451 	return 0;
452 }
453 
454 static const struct of_device_id video_mux_dt_ids[] = {
455 	{ .compatible = "video-mux", },
456 	{ /* sentinel */ }
457 };
458 MODULE_DEVICE_TABLE(of, video_mux_dt_ids);
459 
460 static struct platform_driver video_mux_driver = {
461 	.probe		= video_mux_probe,
462 	.remove		= video_mux_remove,
463 	.driver		= {
464 		.of_match_table = video_mux_dt_ids,
465 		.name = "video-mux",
466 	},
467 };
468 
469 module_platform_driver(video_mux_driver);
470 
471 MODULE_DESCRIPTION("video stream multiplexer");
472 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
473 MODULE_AUTHOR("Philipp Zabel, Pengutronix");
474 MODULE_LICENSE("GPL");
475