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, 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 } 267 EXPORT_SYMBOL_GPL(v4l2_mc_create_media_graph); 268 269 int 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; 283 end: 284 mutex_unlock(&mdev->graph_mutex); 285 return ret; 286 } 287 EXPORT_SYMBOL_GPL(v4l_enable_media_source); 288 289 void 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 } 300 EXPORT_SYMBOL_GPL(v4l_disable_media_source); 301 302 int 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 } 310 EXPORT_SYMBOL_GPL(v4l_vb2q_enable_media_source); 311 312 /* ----------------------------------------------------------------------------- 313 * Pipeline power management 314 * 315 * Entities must be powered up when part of a pipeline that contains at least 316 * one open video device node. 317 * 318 * To achieve this use the entity use_count field to track the number of users. 319 * For entities corresponding to video device nodes the use_count field stores 320 * the users count of the node. For entities corresponding to subdevs the 321 * use_count field stores the total number of users of all video device nodes 322 * in the pipeline. 323 * 324 * The v4l2_pipeline_pm_use() function must be called in the open() and 325 * close() handlers of video device nodes. It increments or decrements the use 326 * count of all subdev entities in the pipeline. 327 * 328 * To react to link management on powered pipelines, the link setup notification 329 * callback updates the use count of all entities in the source and sink sides 330 * of the link. 331 */ 332 333 /* 334 * pipeline_pm_use_count - Count the number of users of a pipeline 335 * @entity: The entity 336 * 337 * Return the total number of users of all video device nodes in the pipeline. 338 */ 339 static int pipeline_pm_use_count(struct media_entity *entity, 340 struct media_graph *graph) 341 { 342 int use = 0; 343 344 media_graph_walk_start(graph, entity); 345 346 while ((entity = media_graph_walk_next(graph))) { 347 if (is_media_entity_v4l2_video_device(entity)) 348 use += entity->use_count; 349 } 350 351 return use; 352 } 353 354 /* 355 * pipeline_pm_power_one - Apply power change to an entity 356 * @entity: The entity 357 * @change: Use count change 358 * 359 * Change the entity use count by @change. If the entity is a subdev update its 360 * power state by calling the core::s_power operation when the use count goes 361 * from 0 to != 0 or from != 0 to 0. 362 * 363 * Return 0 on success or a negative error code on failure. 364 */ 365 static int pipeline_pm_power_one(struct media_entity *entity, int change) 366 { 367 struct v4l2_subdev *subdev; 368 int ret; 369 370 subdev = is_media_entity_v4l2_subdev(entity) 371 ? media_entity_to_v4l2_subdev(entity) : NULL; 372 373 if (entity->use_count == 0 && change > 0 && subdev != NULL) { 374 ret = v4l2_subdev_call(subdev, core, s_power, 1); 375 if (ret < 0 && ret != -ENOIOCTLCMD) 376 return ret; 377 } 378 379 entity->use_count += change; 380 WARN_ON(entity->use_count < 0); 381 382 if (entity->use_count == 0 && change < 0 && subdev != NULL) 383 v4l2_subdev_call(subdev, core, s_power, 0); 384 385 return 0; 386 } 387 388 /* 389 * pipeline_pm_power - Apply power change to all entities in a pipeline 390 * @entity: The entity 391 * @change: Use count change 392 * 393 * Walk the pipeline to update the use count and the power state of all non-node 394 * entities. 395 * 396 * Return 0 on success or a negative error code on failure. 397 */ 398 static int pipeline_pm_power(struct media_entity *entity, int change, 399 struct media_graph *graph) 400 { 401 struct media_entity *first = entity; 402 int ret = 0; 403 404 if (!change) 405 return 0; 406 407 media_graph_walk_start(graph, entity); 408 409 while (!ret && (entity = media_graph_walk_next(graph))) 410 if (is_media_entity_v4l2_subdev(entity)) 411 ret = pipeline_pm_power_one(entity, change); 412 413 if (!ret) 414 return ret; 415 416 media_graph_walk_start(graph, first); 417 418 while ((first = media_graph_walk_next(graph)) 419 && first != entity) 420 if (is_media_entity_v4l2_subdev(first)) 421 pipeline_pm_power_one(first, -change); 422 423 return ret; 424 } 425 426 int v4l2_pipeline_pm_use(struct media_entity *entity, int use) 427 { 428 struct media_device *mdev = entity->graph_obj.mdev; 429 int change = use ? 1 : -1; 430 int ret; 431 432 mutex_lock(&mdev->graph_mutex); 433 434 /* Apply use count to node. */ 435 entity->use_count += change; 436 WARN_ON(entity->use_count < 0); 437 438 /* Apply power change to connected non-nodes. */ 439 ret = pipeline_pm_power(entity, change, &mdev->pm_count_walk); 440 if (ret < 0) 441 entity->use_count -= change; 442 443 mutex_unlock(&mdev->graph_mutex); 444 445 return ret; 446 } 447 EXPORT_SYMBOL_GPL(v4l2_pipeline_pm_use); 448 449 int v4l2_pipeline_link_notify(struct media_link *link, u32 flags, 450 unsigned int notification) 451 { 452 struct media_graph *graph = &link->graph_obj.mdev->pm_count_walk; 453 struct media_entity *source = link->source->entity; 454 struct media_entity *sink = link->sink->entity; 455 int source_use; 456 int sink_use; 457 int ret = 0; 458 459 source_use = pipeline_pm_use_count(source, graph); 460 sink_use = pipeline_pm_use_count(sink, graph); 461 462 if (notification == MEDIA_DEV_NOTIFY_POST_LINK_CH && 463 !(flags & MEDIA_LNK_FL_ENABLED)) { 464 /* Powering off entities is assumed to never fail. */ 465 pipeline_pm_power(source, -sink_use, graph); 466 pipeline_pm_power(sink, -source_use, graph); 467 return 0; 468 } 469 470 if (notification == MEDIA_DEV_NOTIFY_PRE_LINK_CH && 471 (flags & MEDIA_LNK_FL_ENABLED)) { 472 473 ret = pipeline_pm_power(source, sink_use, graph); 474 if (ret < 0) 475 return ret; 476 477 ret = pipeline_pm_power(sink, source_use, graph); 478 if (ret < 0) 479 pipeline_pm_power(source, -sink_use, graph); 480 } 481 482 return ret; 483 } 484 EXPORT_SYMBOL_GPL(v4l2_pipeline_link_notify); 485