LXR linux/drivers/media/v4l2-core/v4l2-mc.c

   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 tuner 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)
 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, 0);
 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);
 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);
 592