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  1// SPDX-License-Identifier: GPL-2.0-or-later
  2
  3/*
  4 * Media Controller ancillary functions
  5 *
  6 * Copyright (c) 2016 Mauro Carvalho Chehab <mchehab@kernel.org>
  7 * Copyright (C) 2016 Shuah Khan <shuahkh@osg.samsung.com>
  8 * Copyright (C) 2006-2010 Nokia Corporation
  9 * Copyright (c) 2016 Intel Corporation.
 10 */
 11
 12#include <linux/module.h>
 13#include <linux/pci.h>
 14#include <linux/usb.h>
 15#include <media/media-device.h>
 16#include <media/media-entity.h>
 17#include <media/v4l2-fh.h>
 18#include <media/v4l2-mc.h>
 19#include <media/v4l2-subdev.h>
 20#include <media/videobuf2-core.h>
 21
 22int v4l2_mc_create_media_graph(struct media_device *mdev)
 23
 24{
 25	struct media_entity *entity;
 26	struct media_entity *if_vid = NULL, *if_aud = NULL;
 27	struct media_entity *tuner = NULL, *decoder = NULL;
 28	struct media_entity *io_v4l = NULL, *io_vbi = NULL, *io_swradio = NULL;
 29	bool is_webcam = false;
 30	u32 flags;
 31	int ret, pad_sink, pad_source;
 32
 33	if (!mdev)
 34		return 0;
 35
 36	media_device_for_each_entity(entity, mdev) {
 37		switch (entity->function) {
 38		case MEDIA_ENT_F_IF_VID_DECODER:
 39			if_vid = entity;
 40			break;
 41		case MEDIA_ENT_F_IF_AUD_DECODER:
 42			if_aud = entity;
 43			break;
 44		case MEDIA_ENT_F_TUNER:
 45			tuner = entity;
 46			break;
 47		case MEDIA_ENT_F_ATV_DECODER:
 48			decoder = entity;
 49			break;
 50		case MEDIA_ENT_F_IO_V4L:
 51			io_v4l = entity;
 52			break;
 53		case MEDIA_ENT_F_IO_VBI:
 54			io_vbi = entity;
 55			break;
 56		case MEDIA_ENT_F_IO_SWRADIO:
 57			io_swradio = entity;
 58			break;
 59		case MEDIA_ENT_F_CAM_SENSOR:
 60			is_webcam = true;
 61			break;
 62		}
 63	}
 64
 65	/* It should have at least one I/O entity */
 66	if (!io_v4l && !io_vbi && !io_swradio) {
 67		dev_warn(mdev->dev, "Didn't find any I/O entity\n");
 68		return -EINVAL;
 69	}
 70
 71	/*
 72	 * Here, webcams are modelled on a very simple way: the sensor is
 73	 * connected directly to the I/O entity. All dirty details, like
 74	 * scaler and crop HW are hidden. While such mapping is not enough
 75	 * for mc-centric hardware, it is enough for v4l2 interface centric
 76	 * PC-consumer's hardware.
 77	 */
 78	if (is_webcam) {
 79		if (!io_v4l) {
 80			dev_warn(mdev->dev, "Didn't find a MEDIA_ENT_F_IO_V4L\n");
 81			return -EINVAL;
 82		}
 83
 84		media_device_for_each_entity(entity, mdev) {
 85			if (entity->function != MEDIA_ENT_F_CAM_SENSOR)
 86				continue;
 87			ret = media_create_pad_link(entity, 0,
 88						    io_v4l, 0,
 89						    MEDIA_LNK_FL_ENABLED);
 90			if (ret) {
 91				dev_warn(mdev->dev, "Failed to create a sensor link\n");
 92				return ret;
 93			}
 94		}
 95		if (!decoder)
 96			return 0;
 97	}
 98
 99	/* The device isn't a webcam. So, it should have a decoder */
100	if (!decoder) {
101		dev_warn(mdev->dev, "Decoder not found\n");
102		return -EINVAL;
103	}
104
105	/* Link the tuner and IF video output pads */
106	if (tuner) {
107		if (if_vid) {
108			pad_source = media_get_pad_index(tuner, false,
109							 PAD_SIGNAL_ANALOG);
110			pad_sink = media_get_pad_index(if_vid, true,
111						       PAD_SIGNAL_ANALOG);
112			if (pad_source < 0 || pad_sink < 0) {
113				dev_warn(mdev->dev, "Couldn't get tuner and/or PLL pad(s): (%d, %d)\n",
114					 pad_source, pad_sink);
115				return -EINVAL;
116			}
117			ret = media_create_pad_link(tuner, pad_source,
118						    if_vid, pad_sink,
119						    MEDIA_LNK_FL_ENABLED);
120			if (ret) {
121				dev_warn(mdev->dev, "Couldn't create tuner->PLL link)\n");
122				return ret;
123			}
124
125			pad_source = media_get_pad_index(if_vid, false,
126							 PAD_SIGNAL_ANALOG);
127			pad_sink = media_get_pad_index(decoder, true,
128						       PAD_SIGNAL_ANALOG);
129			if (pad_source < 0 || pad_sink < 0) {
130				dev_warn(mdev->dev, "get decoder and/or PLL pad(s): (%d, %d)\n",
131					 pad_source, pad_sink);
132				return -EINVAL;
133			}
134			ret = media_create_pad_link(if_vid, pad_source,
135						    decoder, pad_sink,
136						    MEDIA_LNK_FL_ENABLED);
137			if (ret) {
138				dev_warn(mdev->dev, "couldn't link PLL to decoder\n");
139				return ret;
140			}
141		} else {
142			pad_source = media_get_pad_index(tuner, false,
143							 PAD_SIGNAL_ANALOG);
144			pad_sink = media_get_pad_index(decoder, true,
145						       PAD_SIGNAL_ANALOG);
146			if (pad_source < 0 || pad_sink < 0) {
147				dev_warn(mdev->dev, "couldn't get tuner and/or decoder pad(s): (%d, %d)\n",
148					 pad_source, pad_sink);
149				return -EINVAL;
150			}
151			ret = media_create_pad_link(tuner, pad_source,
152						    decoder, pad_sink,
153						    MEDIA_LNK_FL_ENABLED);
154			if (ret)
155				return ret;
156		}
157
158		if (if_aud) {
159			pad_source = media_get_pad_index(tuner, false,
160							 PAD_SIGNAL_AUDIO);
161			pad_sink = media_get_pad_index(if_aud, true,
162						       PAD_SIGNAL_AUDIO);
163			if (pad_source < 0 || pad_sink < 0) {
164				dev_warn(mdev->dev, "couldn't get tuner and/or decoder pad(s) for audio: (%d, %d)\n",
165					 pad_source, pad_sink);
166				return -EINVAL;
167			}
168			ret = media_create_pad_link(tuner, pad_source,
169						    if_aud, pad_sink,
170						    MEDIA_LNK_FL_ENABLED);
171			if (ret) {
172				dev_warn(mdev->dev, "couldn't link tuner->audio PLL\n");
173				return ret;
174			}
175		} else {
176			if_aud = tuner;
177		}
178
179	}
180
181	/* Create demod to V4L, VBI and SDR radio links */
182	if (io_v4l) {
183		pad_source = media_get_pad_index(decoder, false, PAD_SIGNAL_DV);
184		if (pad_source < 0) {
185			dev_warn(mdev->dev, "couldn't get decoder output pad for V4L I/O\n");
186			return -EINVAL;
187		}
188		ret = media_create_pad_link(decoder, pad_source,
189					    io_v4l, 0,
190					    MEDIA_LNK_FL_ENABLED);
191		if (ret) {
192			dev_warn(mdev->dev, "couldn't link decoder output to V4L I/O\n");
193			return ret;
194		}
195	}
196
197	if (io_swradio) {
198		pad_source = media_get_pad_index(decoder, false, PAD_SIGNAL_DV);
199		if (pad_source < 0) {
200			dev_warn(mdev->dev, "couldn't get decoder output pad for SDR\n");
201			return -EINVAL;
202		}
203		ret = media_create_pad_link(decoder, pad_source,
204					    io_swradio, 0,
205					    MEDIA_LNK_FL_ENABLED);
206		if (ret) {
207			dev_warn(mdev->dev, "couldn't link decoder output to SDR\n");
208			return ret;
209		}
210	}
211
212	if (io_vbi) {
213		pad_source = media_get_pad_index(decoder, false, PAD_SIGNAL_DV);
214		if (pad_source < 0) {
215			dev_warn(mdev->dev, "couldn't get decoder output pad for VBI\n");
216			return -EINVAL;
217		}
218		ret = media_create_pad_link(decoder, pad_source,
219					    io_vbi, 0,
220					    MEDIA_LNK_FL_ENABLED);
221		if (ret) {
222			dev_warn(mdev->dev, "couldn't link decoder output to VBI\n");
223			return ret;
224		}
225	}
226
227	/* Create links for the media connectors */
228	flags = MEDIA_LNK_FL_ENABLED;
229	media_device_for_each_entity(entity, mdev) {
230		switch (entity->function) {
231		case MEDIA_ENT_F_CONN_RF:
232			if (!tuner)
233				continue;
234			pad_sink = media_get_pad_index(tuner, true,
235						       PAD_SIGNAL_ANALOG);
236			if (pad_sink < 0) {
237				dev_warn(mdev->dev, "couldn't get tuner analog pad sink\n");
238				return -EINVAL;
239			}
240			ret = media_create_pad_link(entity, 0, tuner,
241						    pad_sink,
242						    flags);
243			break;
244		case MEDIA_ENT_F_CONN_SVIDEO:
245		case MEDIA_ENT_F_CONN_COMPOSITE:
246			pad_sink = media_get_pad_index(decoder, true,
247						       PAD_SIGNAL_ANALOG);
248			if (pad_sink < 0) {
249				dev_warn(mdev->dev, "couldn't get decoder analog pad sink\n");
250				return -EINVAL;
251			}
252			ret = media_create_pad_link(entity, 0, decoder,
253						    pad_sink,
254						    flags);
255			break;
256		default:
257			continue;
258		}
259		if (ret)
260			return ret;
261
262		flags = 0;
263	}
264
265	return 0;
266}
267EXPORT_SYMBOL_GPL(v4l2_mc_create_media_graph);
268
269int v4l_enable_media_source(struct video_device *vdev)
270{
271	struct media_device *mdev = vdev->entity.graph_obj.mdev;
272	int ret = 0, err;
273
274	if (!mdev)
275		return 0;
276
277	mutex_lock(&mdev->graph_mutex);
278	if (!mdev->enable_source)
279		goto end;
280	err = mdev->enable_source(&vdev->entity, &vdev->pipe);
281	if (err)
282		ret = -EBUSY;
283end:
284	mutex_unlock(&mdev->graph_mutex);
285	return ret;
286}
287EXPORT_SYMBOL_GPL(v4l_enable_media_source);
288
289void v4l_disable_media_source(struct video_device *vdev)
290{
291	struct media_device *mdev = vdev->entity.graph_obj.mdev;
292
293	if (mdev) {
294		mutex_lock(&mdev->graph_mutex);
295		if (mdev->disable_source)
296			mdev->disable_source(&vdev->entity);
297		mutex_unlock(&mdev->graph_mutex);
298	}
299}
300EXPORT_SYMBOL_GPL(v4l_disable_media_source);
301
302int v4l_vb2q_enable_media_source(struct vb2_queue *q)
303{
304	struct v4l2_fh *fh = q->owner;
305
306	if (fh && fh->vdev)
307		return v4l_enable_media_source(fh->vdev);
308	return 0;
309}
310EXPORT_SYMBOL_GPL(v4l_vb2q_enable_media_source);
311
312int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
313				    struct media_pad *sink, u32 flags)
314{
315	struct fwnode_handle *endpoint;
316	struct v4l2_subdev *sink_sd;
317
318	if (!(sink->flags & MEDIA_PAD_FL_SINK) ||
319	    !is_media_entity_v4l2_subdev(sink->entity))
320		return -EINVAL;
321
322	sink_sd = media_entity_to_v4l2_subdev(sink->entity);
323
324	fwnode_graph_for_each_endpoint(dev_fwnode(src_sd->dev), endpoint) {
325		struct fwnode_handle *remote_ep;
326		int src_idx, sink_idx, ret;
327		struct media_pad *src;
328
329		src_idx = media_entity_get_fwnode_pad(&src_sd->entity,
330						      endpoint,
331						      MEDIA_PAD_FL_SOURCE);
332		if (src_idx < 0)
333			continue;
334
335		remote_ep = fwnode_graph_get_remote_endpoint(endpoint);
336		if (!remote_ep)
337			continue;
338
339		/*
340		 * ask the sink to verify it owns the remote endpoint,
341		 * and translate to a sink pad.
342		 */
343		sink_idx = media_entity_get_fwnode_pad(&sink_sd->entity,
344						       remote_ep,
345						       MEDIA_PAD_FL_SINK);
346		fwnode_handle_put(remote_ep);
347
348		if (sink_idx < 0 || sink_idx != sink->index)
349			continue;
350
351		/*
352		 * the source endpoint corresponds to one of its source pads,
353		 * the source endpoint connects to an endpoint at the sink
354		 * entity, and the sink endpoint corresponds to the sink
355		 * pad requested, so we have found an endpoint connection
356		 * that works, create the media link for it.
357		 */
358
359		src = &src_sd->entity.pads[src_idx];
360
361		/* skip if link already exists */
362		if (media_entity_find_link(src, sink))
363			continue;
364
365		dev_dbg(sink_sd->dev, "creating link %s:%d -> %s:%d\n",
366			src_sd->entity.name, src_idx,
367			sink_sd->entity.name, sink_idx);
368
369		ret = media_create_pad_link(&src_sd->entity, src_idx,
370					    &sink_sd->entity, sink_idx, flags);
371		if (ret) {
372			dev_err(sink_sd->dev,
373				"link %s:%d -> %s:%d failed with %d\n",
374				src_sd->entity.name, src_idx,
375				sink_sd->entity.name, sink_idx, ret);
376
377			fwnode_handle_put(endpoint);
378			return ret;
379		}
380	}
381
382	return 0;
383}
384EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links_to_pad);
385
386int v4l2_create_fwnode_links(struct v4l2_subdev *src_sd,
387			     struct v4l2_subdev *sink_sd)
388{
389	unsigned int i;
390
391	for (i = 0; i < sink_sd->entity.num_pads; i++) {
392		struct media_pad *pad = &sink_sd->entity.pads[i];
393		int ret;
394
395		if (!(pad->flags & MEDIA_PAD_FL_SINK))
396			continue;
397
398		ret = v4l2_create_fwnode_links_to_pad(src_sd, pad, 0);
399		if (ret)
400			return ret;
401	}
402
403	return 0;
404}
405EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links);
406
407/* -----------------------------------------------------------------------------
408 * Pipeline power management
409 *
410 * Entities must be powered up when part of a pipeline that contains at least
411 * one open video device node.
412 *
413 * To achieve this use the entity use_count field to track the number of users.
414 * For entities corresponding to video device nodes the use_count field stores
415 * the users count of the node. For entities corresponding to subdevs the
416 * use_count field stores the total number of users of all video device nodes
417 * in the pipeline.
418 *
419 * The v4l2_pipeline_pm_{get, put}() functions must be called in the open() and
420 * close() handlers of video device nodes. It increments or decrements the use
421 * count of all subdev entities in the pipeline.
422 *
423 * To react to link management on powered pipelines, the link setup notification
424 * callback updates the use count of all entities in the source and sink sides
425 * of the link.
426 */
427
428/*
429 * pipeline_pm_use_count - Count the number of users of a pipeline
430 * @entity: The entity
431 *
432 * Return the total number of users of all video device nodes in the pipeline.
433 */
434static int pipeline_pm_use_count(struct media_entity *entity,
435	struct media_graph *graph)
436{
437	int use = 0;
438
439	media_graph_walk_start(graph, entity);
440
441	while ((entity = media_graph_walk_next(graph))) {
442		if (is_media_entity_v4l2_video_device(entity))
443			use += entity->use_count;
444	}
445
446	return use;
447}
448
449/*
450 * pipeline_pm_power_one - Apply power change to an entity
451 * @entity: The entity
452 * @change: Use count change
453 *
454 * Change the entity use count by @change. If the entity is a subdev update its
455 * power state by calling the core::s_power operation when the use count goes
456 * from 0 to != 0 or from != 0 to 0.
457 *
458 * Return 0 on success or a negative error code on failure.
459 */
460static int pipeline_pm_power_one(struct media_entity *entity, int change)
461{
462	struct v4l2_subdev *subdev;
463	int ret;
464
465	subdev = is_media_entity_v4l2_subdev(entity)
466	       ? media_entity_to_v4l2_subdev(entity) : NULL;
467
468	if (entity->use_count == 0 && change > 0 && subdev != NULL) {
469		ret = v4l2_subdev_call(subdev, core, s_power, 1);
470		if (ret < 0 && ret != -ENOIOCTLCMD)
471			return ret;
472	}
473
474	entity->use_count += change;
475	WARN_ON(entity->use_count < 0);
476
477	if (entity->use_count == 0 && change < 0 && subdev != NULL)
478		v4l2_subdev_call(subdev, core, s_power, 0);
479
480	return 0;
481}
482
483/*
484 * pipeline_pm_power - Apply power change to all entities in a pipeline
485 * @entity: The entity
486 * @change: Use count change
487 *
488 * Walk the pipeline to update the use count and the power state of all non-node
489 * entities.
490 *
491 * Return 0 on success or a negative error code on failure.
492 */
493static int pipeline_pm_power(struct media_entity *entity, int change,
494	struct media_graph *graph)
495{
496	struct media_entity *first = entity;
497	int ret = 0;
498
499	if (!change)
500		return 0;
501
502	media_graph_walk_start(graph, entity);
503
504	while (!ret && (entity = media_graph_walk_next(graph)))
505		if (is_media_entity_v4l2_subdev(entity))
506			ret = pipeline_pm_power_one(entity, change);
507
508	if (!ret)
509		return ret;
510
511	media_graph_walk_start(graph, first);
512
513	while ((first = media_graph_walk_next(graph))
514	       && first != entity)
515		if (is_media_entity_v4l2_subdev(first))
516			pipeline_pm_power_one(first, -change);
517
518	return ret;
519}
520
521static int v4l2_pipeline_pm_use(struct media_entity *entity, unsigned int use)
522{
523	struct media_device *mdev = entity->graph_obj.mdev;
524	int change = use ? 1 : -1;
525	int ret;
526
527	mutex_lock(&mdev->graph_mutex);
528
529	/* Apply use count to node. */
530	entity->use_count += change;
531	WARN_ON(entity->use_count < 0);
532
533	/* Apply power change to connected non-nodes. */
534	ret = pipeline_pm_power(entity, change, &mdev->pm_count_walk);
535	if (ret < 0)
536		entity->use_count -= change;
537
538	mutex_unlock(&mdev->graph_mutex);
539
540	return ret;
541}
542
543int v4l2_pipeline_pm_get(struct media_entity *entity)
544{
545	return v4l2_pipeline_pm_use(entity, 1);
546}
547EXPORT_SYMBOL_GPL(v4l2_pipeline_pm_get);
548
549void v4l2_pipeline_pm_put(struct media_entity *entity)
550{
551	/* Powering off entities shouldn't fail. */
552	WARN_ON(v4l2_pipeline_pm_use(entity, 0));
553}
554EXPORT_SYMBOL_GPL(v4l2_pipeline_pm_put);
555
556int v4l2_pipeline_link_notify(struct media_link *link, u32 flags,
557			      unsigned int notification)
558{
559	struct media_graph *graph = &link->graph_obj.mdev->pm_count_walk;
560	struct media_entity *source = link->source->entity;
561	struct media_entity *sink = link->sink->entity;
562	int source_use;
563	int sink_use;
564	int ret = 0;
565
566	source_use = pipeline_pm_use_count(source, graph);
567	sink_use = pipeline_pm_use_count(sink, graph);
568
569	if (notification == MEDIA_DEV_NOTIFY_POST_LINK_CH &&
570	    !(flags & MEDIA_LNK_FL_ENABLED)) {
571		/* Powering off entities is assumed to never fail. */
572		pipeline_pm_power(source, -sink_use, graph);
573		pipeline_pm_power(sink, -source_use, graph);
574		return 0;
575	}
576
577	if (notification == MEDIA_DEV_NOTIFY_PRE_LINK_CH &&
578		(flags & MEDIA_LNK_FL_ENABLED)) {
579
580		ret = pipeline_pm_power(source, sink_use, graph);
581		if (ret < 0)
582			return ret;
583
584		ret = pipeline_pm_power(sink, source_use, graph);
585		if (ret < 0)
586			pipeline_pm_power(source, -sink_use, graph);
587	}
588
589	return ret;
590}
591EXPORT_SYMBOL_GPL(v4l2_pipeline_link_notify);