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
  22 int 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,
 109                                                          MEDIA_PAD_FL_SOURCE,
 110                                                          PAD_SIGNAL_ANALOG);
 111                         pad_sink = media_get_pad_index(if_vid,
 112                                                        MEDIA_PAD_FL_SINK,
 113                                                        PAD_SIGNAL_ANALOG);
 114                         if (pad_source < 0 || pad_sink < 0) {
 115                                 dev_warn(mdev->dev, "Couldn't get tuner and/or PLL pad(s): (%d, %d)\n",
 116                                          pad_source, pad_sink);
 117                                 return -EINVAL;
 118                         }
 119                         ret = media_create_pad_link(tuner, pad_source,
 120                                                     if_vid, pad_sink,
 121                                                     MEDIA_LNK_FL_ENABLED);
 122                         if (ret) {
 123                                 dev_warn(mdev->dev, "Couldn't create tuner->PLL link)\n");
 124                                 return ret;
 125                         }
 126
 127                         pad_source = media_get_pad_index(if_vid,
 128                                                          MEDIA_PAD_FL_SOURCE,
 129                                                          PAD_SIGNAL_ANALOG);
 130                         pad_sink = media_get_pad_index(decoder,
 131                                                        MEDIA_PAD_FL_SINK,
 132                                                        PAD_SIGNAL_ANALOG);
 133                         if (pad_source < 0 || pad_sink < 0) {
 134                                 dev_warn(mdev->dev, "get decoder and/or PLL pad(s): (%d, %d)\n",
 135                                          pad_source, pad_sink);
 136                                 return -EINVAL;
 137                         }
 138                         ret = media_create_pad_link(if_vid, pad_source,
 139                                                     decoder, pad_sink,
 140                                                     MEDIA_LNK_FL_ENABLED);
 141                         if (ret) {
 142                                 dev_warn(mdev->dev, "couldn't link PLL to decoder\n");
 143                                 return ret;
 144                         }
 145                 } else {
 146                         pad_source = media_get_pad_index(tuner,
 147                                                          MEDIA_PAD_FL_SOURCE,
 148                                                          PAD_SIGNAL_ANALOG);
 149                         pad_sink = media_get_pad_index(decoder,
 150                                                        MEDIA_PAD_FL_SINK,
 151                                                        PAD_SIGNAL_ANALOG);
 152                         if (pad_source < 0 || pad_sink < 0) {
 153                                 dev_warn(mdev->dev, "couldn't get tuner and/or decoder pad(s): (%d, %d)\n",
 154                                          pad_source, pad_sink);
 155                                 return -EINVAL;
 156                         }
 157                         ret = media_create_pad_link(tuner, pad_source,
 158                                                     decoder, pad_sink,
 159                                                     MEDIA_LNK_FL_ENABLED);
 160                         if (ret)
 161                                 return ret;
 162                 }
 163
 164                 if (if_aud) {
 165                         pad_source = media_get_pad_index(tuner,
 166                                                          MEDIA_PAD_FL_SOURCE,
 167                                                          PAD_SIGNAL_AUDIO);
 168                         pad_sink = media_get_pad_index(if_aud,
 169                                                        MEDIA_PAD_FL_SINK,
 170                                                        PAD_SIGNAL_AUDIO);
 171                         if (pad_source < 0 || pad_sink < 0) {
 172                                 dev_warn(mdev->dev, "couldn't get tuner and/or decoder pad(s) for audio: (%d, %d)\n",
 173                                          pad_source, pad_sink);
 174                                 return -EINVAL;
 175                         }
 176                         ret = media_create_pad_link(tuner, pad_source,
 177                                                     if_aud, pad_sink,
 178                                                     MEDIA_LNK_FL_ENABLED);
 179                         if (ret) {
 180                                 dev_warn(mdev->dev, "couldn't link tuner->audio PLL\n");
 181                                 return ret;
 182                         }
 183                 } else {
 184                         if_aud = tuner;
 185                 }
 186
 187         }
 188
 189         /* Create demod to V4L, VBI and SDR radio links */
 190         if (io_v4l) {
 191                 pad_source = media_get_pad_index(decoder, MEDIA_PAD_FL_SOURCE,
 192                                                  PAD_SIGNAL_DV);
 193                 if (pad_source < 0) {
 194                         dev_warn(mdev->dev, "couldn't get decoder output pad for V4L I/O\n");
 195                         return -EINVAL;
 196                 }
 197                 ret = media_create_pad_link(decoder, pad_source,
 198                                             io_v4l, 0,
 199                                             MEDIA_LNK_FL_ENABLED);
 200                 if (ret) {
 201                         dev_warn(mdev->dev, "couldn't link decoder output to V4L I/O\n");
 202                         return ret;
 203                 }
 204         }
 205
 206         if (io_swradio) {
 207                 pad_source = media_get_pad_index(decoder, MEDIA_PAD_FL_SOURCE,
 208                                                  PAD_SIGNAL_DV);
 209                 if (pad_source < 0) {
 210                         dev_warn(mdev->dev, "couldn't get decoder output pad for SDR\n");
 211                         return -EINVAL;
 212                 }
 213                 ret = media_create_pad_link(decoder, pad_source,
 214                                             io_swradio, 0,
 215                                             MEDIA_LNK_FL_ENABLED);
 216                 if (ret) {
 217                         dev_warn(mdev->dev, "couldn't link decoder output to SDR\n");
 218                         return ret;
 219                 }
 220         }
 221
 222         if (io_vbi) {
 223                 pad_source = media_get_pad_index(decoder, MEDIA_PAD_FL_SOURCE,
 224                                                  PAD_SIGNAL_DV);
 225                 if (pad_source < 0) {
 226                         dev_warn(mdev->dev, "couldn't get decoder output pad for VBI\n");
 227                         return -EINVAL;
 228                 }
 229                 ret = media_create_pad_link(decoder, pad_source,
 230                                             io_vbi, 0,
 231                                             MEDIA_LNK_FL_ENABLED);
 232                 if (ret) {
 233                         dev_warn(mdev->dev, "couldn't link decoder output to VBI\n");
 234                         return ret;
 235                 }
 236         }
 237
 238         /* Create links for the media connectors */
 239         flags = MEDIA_LNK_FL_ENABLED;
 240         media_device_for_each_entity(entity, mdev) {
 241                 switch (entity->function) {
 242                 case MEDIA_ENT_F_CONN_RF:
 243                         if (!tuner)
 244                                 continue;
 245                         pad_sink = media_get_pad_index(tuner, MEDIA_PAD_FL_SINK,
 246                                                        PAD_SIGNAL_ANALOG);
 247                         if (pad_sink < 0) {
 248                                 dev_warn(mdev->dev, "couldn't get tuner analog pad sink\n");
 249                                 return -EINVAL;
 250                         }
 251                         ret = media_create_pad_link(entity, 0, tuner,
 252                                                     pad_sink,
 253                                                     flags);
 254                         break;
 255                 case MEDIA_ENT_F_CONN_SVIDEO:
 256                 case MEDIA_ENT_F_CONN_COMPOSITE:
 257                         pad_sink = media_get_pad_index(decoder,
 258                                                        MEDIA_PAD_FL_SINK,
 259                                                        PAD_SIGNAL_ANALOG);
 260                         if (pad_sink < 0) {
 261                                 dev_warn(mdev->dev, "couldn't get decoder analog pad sink\n");
 262                                 return -EINVAL;
 263                         }
 264                         ret = media_create_pad_link(entity, 0, decoder,
 265                                                     pad_sink,
 266                                                     flags);
 267                         break;
 268                 default:
 269                         continue;
 270                 }
 271                 if (ret)
 272                         return ret;
 273
 274                 flags = 0;
 275         }
 276
 277         return 0;
 278 }
 279 EXPORT_SYMBOL_GPL(v4l2_mc_create_media_graph);
 280
 281 int v4l_enable_media_source(struct video_device *vdev)
 282 {
 283         struct media_device *mdev = vdev->entity.graph_obj.mdev;
 284         int ret = 0, err;
 285
 286         if (!mdev)
 287                 return 0;
 288
 289         mutex_lock(&mdev->graph_mutex);
 290         if (!mdev->enable_source)
 291                 goto end;
 292         err = mdev->enable_source(&vdev->entity, &vdev->pipe);
 293         if (err)
 294                 ret = -EBUSY;
 295 end:
 296         mutex_unlock(&mdev->graph_mutex);
 297         return ret;
 298 }
 299 EXPORT_SYMBOL_GPL(v4l_enable_media_source);
 300
 301 void v4l_disable_media_source(struct video_device *vdev)
 302 {
 303         struct media_device *mdev = vdev->entity.graph_obj.mdev;
 304
 305         if (mdev) {
 306                 mutex_lock(&mdev->graph_mutex);
 307                 if (mdev->disable_source)
 308                         mdev->disable_source(&vdev->entity);
 309                 mutex_unlock(&mdev->graph_mutex);
 310         }
 311 }
 312 EXPORT_SYMBOL_GPL(v4l_disable_media_source);
 313
 314 int v4l_vb2q_enable_media_source(struct vb2_queue *q)
 315 {
 316         struct v4l2_fh *fh = q->owner;
 317
 318         if (fh && fh->vdev)
 319                 return v4l_enable_media_source(fh->vdev);
 320         return 0;
 321 }
 322 EXPORT_SYMBOL_GPL(v4l_vb2q_enable_media_source);
 323
 324 int v4l2_create_fwnode_links_to_pad(struct v4l2_subdev *src_sd,
 325                                     struct media_pad *sink, u32 flags)
 326 {
 327         struct fwnode_handle *endpoint;
 328
 329         if (!(sink->flags & MEDIA_PAD_FL_SINK))
 330                 return -EINVAL;
 331
 332         fwnode_graph_for_each_endpoint(dev_fwnode(src_sd->dev), endpoint) {
 333                 struct fwnode_handle *remote_ep;
 334                 int src_idx, sink_idx, ret;
 335                 struct media_pad *src;
 336
 337                 src_idx = media_entity_get_fwnode_pad(&src_sd->entity,
 338                                                       endpoint,
 339                                                       MEDIA_PAD_FL_SOURCE);
 340                 if (src_idx < 0)
 341                         continue;
 342
 343                 remote_ep = fwnode_graph_get_remote_endpoint(endpoint);
 344                 if (!remote_ep)
 345                         continue;
 346
 347                 /*
 348                  * ask the sink to verify it owns the remote endpoint,
 349                  * and translate to a sink pad.
 350                  */
 351                 sink_idx = media_entity_get_fwnode_pad(sink->entity,
 352                                                        remote_ep,
 353                                                        MEDIA_PAD_FL_SINK);
 354                 fwnode_handle_put(remote_ep);
 355
 356                 if (sink_idx < 0 || sink_idx != sink->index)
 357                         continue;
 358
 359                 /*
 360                  * the source endpoint corresponds to one of its source pads,
 361                  * the source endpoint connects to an endpoint at the sink
 362                  * entity, and the sink endpoint corresponds to the sink
 363                  * pad requested, so we have found an endpoint connection
 364                  * that works, create the media link for it.
 365                  */
 366
 367                 src = &src_sd->entity.pads[src_idx];
 368
 369                 /* skip if link already exists */
 370                 if (media_entity_find_link(src, sink))
 371                         continue;
 372
 373                 dev_dbg(src_sd->dev, "creating link %s:%d -> %s:%d\n",
 374                         src_sd->entity.name, src_idx,
 375                         sink->entity->name, sink_idx);
 376
 377                 ret = media_create_pad_link(&src_sd->entity, src_idx,
 378                                             sink->entity, sink_idx, flags);
 379                 if (ret) {
 380                         dev_err(src_sd->dev,
 381                                 "link %s:%d -> %s:%d failed with %d\n",
 382                                 src_sd->entity.name, src_idx,
 383                                 sink->entity->name, sink_idx, ret);
 384
 385                         fwnode_handle_put(endpoint);
 386                         return ret;
 387                 }
 388         }
 389
 390         return 0;
 391 }
 392 EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links_to_pad);
 393
 394 int v4l2_create_fwnode_links(struct v4l2_subdev *src_sd,
 395                              struct v4l2_subdev *sink_sd)
 396 {
 397         unsigned int i;
 398
 399         for (i = 0; i < sink_sd->entity.num_pads; i++) {
 400                 struct media_pad *pad = &sink_sd->entity.pads[i];
 401                 int ret;
 402
 403                 if (!(pad->flags & MEDIA_PAD_FL_SINK))
 404                         continue;
 405
 406                 ret = v4l2_create_fwnode_links_to_pad(src_sd, pad, 0);
 407                 if (ret)
 408                         return ret;
 409         }
 410
 411         return 0;
 412 }
 413 EXPORT_SYMBOL_GPL(v4l2_create_fwnode_links);
 414
 415 /* -----------------------------------------------------------------------------
 416  * Pipeline power management
 417  *
 418  * Entities must be powered up when part of a pipeline that contains at least
 419  * one open video device node.
 420  *
 421  * To achieve this use the entity use_count field to track the number of users.
 422  * For entities corresponding to video device nodes the use_count field stores
 423  * the users count of the node. For entities corresponding to subdevs the
 424  * use_count field stores the total number of users of all video device nodes
 425  * in the pipeline.
 426  *
 427  * The v4l2_pipeline_pm_{get, put}() functions must be called in the open() and
 428  * close() handlers of video device nodes. It increments or decrements the use
 429  * count of all subdev entities in the pipeline.
 430  *
 431  * To react to link management on powered pipelines, the link setup notification
 432  * callback updates the use count of all entities in the source and sink sides
 433  * of the link.
 434  */
 435
 436 /*
 437  * pipeline_pm_use_count - Count the number of users of a pipeline
 438  * @entity: The entity
 439  *
 440  * Return the total number of users of all video device nodes in the pipeline.
 441  */
 442 static int pipeline_pm_use_count(struct media_entity *entity,
 443         struct media_graph *graph)
 444 {
 445         int use = 0;
 446
 447         media_graph_walk_start(graph, entity);
 448
 449         while ((entity = media_graph_walk_next(graph))) {
 450                 if (is_media_entity_v4l2_video_device(entity))
 451                         use += entity->use_count;
 452         }
 453
 454         return use;
 455 }
 456
 457 /*
 458  * pipeline_pm_power_one - Apply power change to an entity
 459  * @entity: The entity
 460  * @change: Use count change
 461  *
 462  * Change the entity use count by @change. If the entity is a subdev update its
 463  * power state by calling the core::s_power operation when the use count goes
 464  * from 0 to != 0 or from != 0 to 0.
 465  *
 466  * Return 0 on success or a negative error code on failure.
 467  */
 468 static int pipeline_pm_power_one(struct media_entity *entity, int change)
 469 {
 470         struct v4l2_subdev *subdev;
 471         int ret;
 472
 473         subdev = is_media_entity_v4l2_subdev(entity)
 474                ? media_entity_to_v4l2_subdev(entity) : NULL;
 475
 476         if (entity->use_count == 0 && change > 0 && subdev != NULL) {
 477                 ret = v4l2_subdev_call(subdev, core, s_power, 1);
 478                 if (ret < 0 && ret != -ENOIOCTLCMD)
 479                         return ret;
 480         }
 481
 482         entity->use_count += change;
 483         WARN_ON(entity->use_count < 0);
 484
 485         if (entity->use_count == 0 && change < 0 && subdev != NULL)
 486                 v4l2_subdev_call(subdev, core, s_power, 0);
 487
 488         return 0;
 489 }
 490
 491 /*
 492  * pipeline_pm_power - Apply power change to all entities in a pipeline
 493  * @entity: The entity
 494  * @change: Use count change
 495  *
 496  * Walk the pipeline to update the use count and the power state of all non-node
 497  * entities.
 498  *
 499  * Return 0 on success or a negative error code on failure.
 500  */
 501 static int pipeline_pm_power(struct media_entity *entity, int change,
 502         struct media_graph *graph)
 503 {
 504         struct media_entity *first = entity;
 505         int ret = 0;
 506
 507         if (!change)
 508                 return 0;
 509
 510         media_graph_walk_start(graph, entity);
 511
 512         while (!ret && (entity = media_graph_walk_next(graph)))
 513                 if (is_media_entity_v4l2_subdev(entity))
 514                         ret = pipeline_pm_power_one(entity, change);
 515
 516         if (!ret)
 517                 return ret;
 518
 519         media_graph_walk_start(graph, first);
 520
 521         while ((first = media_graph_walk_next(graph))
 522                && first != entity)
 523                 if (is_media_entity_v4l2_subdev(first))
 524                         pipeline_pm_power_one(first, -change);
 525
 526         return ret;
 527 }
 528
 529 static int v4l2_pipeline_pm_use(struct media_entity *entity, unsigned int use)
 530 {
 531         struct media_device *mdev = entity->graph_obj.mdev;
 532         int change = use ? 1 : -1;
 533         int ret;
 534
 535         mutex_lock(&mdev->graph_mutex);
 536
 537         /* Apply use count to node. */
 538         entity->use_count += change;
 539         WARN_ON(entity->use_count < 0);
 540
 541         /* Apply power change to connected non-nodes. */
 542         ret = pipeline_pm_power(entity, change, &mdev->pm_count_walk);
 543         if (ret < 0)
 544                 entity->use_count -= change;
 545
 546         mutex_unlock(&mdev->graph_mutex);
 547
 548         return ret;
 549 }
 550
 551 int v4l2_pipeline_pm_get(struct media_entity *entity)
 552 {
 553         return v4l2_pipeline_pm_use(entity, 1);
 554 }
 555 EXPORT_SYMBOL_GPL(v4l2_pipeline_pm_get);
 556
 557 void v4l2_pipeline_pm_put(struct media_entity *entity)
 558 {
 559         /* Powering off entities shouldn't fail. */
 560         WARN_ON(v4l2_pipeline_pm_use(entity, 0));
 561 }
 562 EXPORT_SYMBOL_GPL(v4l2_pipeline_pm_put);
 563
 564 int v4l2_pipeline_link_notify(struct media_link *link, u32 flags,
 565                               unsigned int notification)
 566 {
 567         struct media_graph *graph = &link->graph_obj.mdev->pm_count_walk;
 568         struct media_entity *source = link->source->entity;
 569         struct media_entity *sink = link->sink->entity;
 570         int source_use;
 571         int sink_use;
 572         int ret = 0;
 573
 574         source_use = pipeline_pm_use_count(source, graph);
 575         sink_use = pipeline_pm_use_count(sink, graph);
 576
 577         if (notification == MEDIA_DEV_NOTIFY_POST_LINK_CH &&
 578             !(flags & MEDIA_LNK_FL_ENABLED)) {
 579                 /* Powering off entities is assumed to never fail. */
 580                 pipeline_pm_power(source, -sink_use, graph);
 581                 pipeline_pm_power(sink, -source_use, graph);
 582                 return 0;
 583         }
 584
 585         if (notification == MEDIA_DEV_NOTIFY_PRE_LINK_CH &&
 586                 (flags & MEDIA_LNK_FL_ENABLED)) {
 587
 588                 ret = pipeline_pm_power(source, sink_use, graph);
 589                 if (ret < 0)
 590                         return ret;
 591
 592                 ret = pipeline_pm_power(sink, source_use, graph);
 593                 if (ret < 0)
 594                         pipeline_pm_power(source, -sink_use, graph);
 595         }
 596
 597         return ret;
 598 }
 599 EXPORT_SYMBOL_GPL(v4l2_pipeline_link_notify);