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Release 4.11 drivers/media/v4l2-core/v4l2-mc.c

/*
 * Media Controller ancillary functions
 *
 * Copyright (c) 2016 Mauro Carvalho Chehab <mchehab@kernel.org>
 * Copyright (C) 2016 Shuah Khan <shuahkh@osg.samsung.com>
 * Copyright (C) 2006-2010 Nokia Corporation
 * Copyright (c) 2016 Intel Corporation.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 */

#include <linux/module.h>
#include <linux/pci.h>
#include <linux/usb.h>
#include <media/media-device.h>
#include <media/media-entity.h>
#include <media/v4l2-fh.h>
#include <media/v4l2-mc.h>
#include <media/v4l2-subdev.h>
#include <media/media-device.h>
#include <media/v4l2-mc.h>
#include <media/videobuf2-core.h>


int v4l2_mc_create_media_graph(struct media_device *mdev) { struct media_entity *entity; struct media_entity *if_vid = NULL, *if_aud = NULL; struct media_entity *tuner = NULL, *decoder = NULL; struct media_entity *io_v4l = NULL, *io_vbi = NULL, *io_swradio = NULL; bool is_webcam = false; u32 flags; int ret; if (!mdev) return 0; media_device_for_each_entity(entity, mdev) { switch (entity->function) { case MEDIA_ENT_F_IF_VID_DECODER: if_vid = entity; break; case MEDIA_ENT_F_IF_AUD_DECODER: if_aud = entity; break; case MEDIA_ENT_F_TUNER: tuner = entity; break; case MEDIA_ENT_F_ATV_DECODER: decoder = entity; break; case MEDIA_ENT_F_IO_V4L: io_v4l = entity; break; case MEDIA_ENT_F_IO_VBI: io_vbi = entity; break; case MEDIA_ENT_F_IO_SWRADIO: io_swradio = entity; break; case MEDIA_ENT_F_CAM_SENSOR: is_webcam = true; break; } } /* It should have at least one I/O entity */ if (!io_v4l && !io_vbi && !io_swradio) return -EINVAL; /* * Here, webcams are modelled on a very simple way: the sensor is * connected directly to the I/O entity. All dirty details, like * scaler and crop HW are hidden. While such mapping is not enough * for mc-centric hardware, it is enough for v4l2 interface centric * PC-consumer's hardware. */ if (is_webcam) { if (!io_v4l) return -EINVAL; media_device_for_each_entity(entity, mdev) { if (entity->function != MEDIA_ENT_F_CAM_SENSOR) continue; ret = media_create_pad_link(entity, 0, io_v4l, 0, MEDIA_LNK_FL_ENABLED); if (ret) return ret; } if (!decoder) return 0; } /* The device isn't a webcam. So, it should have a decoder */ if (!decoder) return -EINVAL; /* Link the tuner and IF video output pads */ if (tuner) { if (if_vid) { ret = media_create_pad_link(tuner, TUNER_PAD_OUTPUT, if_vid, IF_VID_DEC_PAD_IF_INPUT, MEDIA_LNK_FL_ENABLED); if (ret) return ret; ret = media_create_pad_link(if_vid, IF_VID_DEC_PAD_OUT, decoder, DEMOD_PAD_IF_INPUT, MEDIA_LNK_FL_ENABLED); if (ret) return ret; } else { ret = media_create_pad_link(tuner, TUNER_PAD_OUTPUT, decoder, DEMOD_PAD_IF_INPUT, MEDIA_LNK_FL_ENABLED); if (ret) return ret; } if (if_aud) { ret = media_create_pad_link(tuner, TUNER_PAD_AUD_OUT, if_aud, IF_AUD_DEC_PAD_IF_INPUT, MEDIA_LNK_FL_ENABLED); if (ret) return ret; } else { if_aud = tuner; } } /* Create demod to V4L, VBI and SDR radio links */ if (io_v4l) { ret = media_create_pad_link(decoder, DEMOD_PAD_VID_OUT, io_v4l, 0, MEDIA_LNK_FL_ENABLED); if (ret) return ret; } if (io_swradio) { ret = media_create_pad_link(decoder, DEMOD_PAD_VID_OUT, io_swradio, 0, MEDIA_LNK_FL_ENABLED); if (ret) return ret; } if (io_vbi) { ret = media_create_pad_link(decoder, DEMOD_PAD_VBI_OUT, io_vbi, 0, MEDIA_LNK_FL_ENABLED); if (ret) return ret; } /* Create links for the media connectors */ flags = MEDIA_LNK_FL_ENABLED; media_device_for_each_entity(entity, mdev) { switch (entity->function) { case MEDIA_ENT_F_CONN_RF: if (!tuner) continue; ret = media_create_pad_link(entity, 0, tuner, TUNER_PAD_RF_INPUT, flags); break; case MEDIA_ENT_F_CONN_SVIDEO: case MEDIA_ENT_F_CONN_COMPOSITE: ret = media_create_pad_link(entity, 0, decoder, DEMOD_PAD_IF_INPUT, flags); break; default: continue; } if (ret) return ret; flags = 0; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Mauro Carvalho Chehab530100.00%1100.00%
Total530100.00%1100.00%

EXPORT_SYMBOL_GPL(v4l2_mc_create_media_graph);
int v4l_enable_media_source(struct video_device *vdev) { struct media_device *mdev = vdev->entity.graph_obj.mdev; int ret = 0, err; if (!mdev) return 0; mutex_lock(&mdev->graph_mutex); if (!mdev->enable_source) goto end; err = mdev->enable_source(&vdev->entity, &vdev->pipe); if (err) ret = -EBUSY; end: mutex_unlock(&mdev->graph_mutex); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Shuah Khan95100.00%2100.00%
Total95100.00%2100.00%

EXPORT_SYMBOL_GPL(v4l_enable_media_source);
void v4l_disable_media_source(struct video_device *vdev) { struct media_device *mdev = vdev->entity.graph_obj.mdev; if (mdev) { mutex_lock(&mdev->graph_mutex); if (mdev->disable_source) mdev->disable_source(&vdev->entity); mutex_unlock(&mdev->graph_mutex); } }

Contributors

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Shuah Khan61100.00%2100.00%
Total61100.00%2100.00%

EXPORT_SYMBOL_GPL(v4l_disable_media_source);
int v4l_vb2q_enable_media_source(struct vb2_queue *q) { struct v4l2_fh *fh = q->owner; if (fh && fh->vdev) return v4l_enable_media_source(fh->vdev); return 0; }

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Shuah Khan38100.00%2100.00%
Total38100.00%2100.00%

EXPORT_SYMBOL_GPL(v4l_vb2q_enable_media_source); /* ----------------------------------------------------------------------------- * Pipeline power management * * Entities must be powered up when part of a pipeline that contains at least * one open video device node. * * To achieve this use the entity use_count field to track the number of users. * For entities corresponding to video device nodes the use_count field stores * the users count of the node. For entities corresponding to subdevs the * use_count field stores the total number of users of all video device nodes * in the pipeline. * * The v4l2_pipeline_pm_use() function must be called in the open() and * close() handlers of video device nodes. It increments or decrements the use * count of all subdev entities in the pipeline. * * To react to link management on powered pipelines, the link setup notification * callback updates the use count of all entities in the source and sink sides * of the link. */ /* * pipeline_pm_use_count - Count the number of users of a pipeline * @entity: The entity * * Return the total number of users of all video device nodes in the pipeline. */
static int pipeline_pm_use_count(struct media_entity *entity, struct media_graph *graph) { int use = 0; media_graph_walk_start(graph, entity); while ((entity = media_graph_walk_next(graph))) { if (is_media_entity_v4l2_video_device(entity)) use += entity->use_count; } return use; }

Contributors

PersonTokensPropCommitsCommitProp
Sakari Ailus5698.25%266.67%
Laurent Pinchart11.75%133.33%
Total57100.00%3100.00%

/* * pipeline_pm_power_one - Apply power change to an entity * @entity: The entity * @change: Use count change * * Change the entity use count by @change. If the entity is a subdev update its * power state by calling the core::s_power operation when the use count goes * from 0 to != 0 or from != 0 to 0. * * Return 0 on success or a negative error code on failure. */
static int pipeline_pm_power_one(struct media_entity *entity, int change) { struct v4l2_subdev *subdev; int ret; subdev = is_media_entity_v4l2_subdev(entity) ? media_entity_to_v4l2_subdev(entity) : NULL; if (entity->use_count == 0 && change > 0 && subdev != NULL) { ret = v4l2_subdev_call(subdev, core, s_power, 1); if (ret < 0 && ret != -ENOIOCTLCMD) return ret; } entity->use_count += change; WARN_ON(entity->use_count < 0); if (entity->use_count == 0 && change < 0 && subdev != NULL) v4l2_subdev_call(subdev, core, s_power, 0); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Sakari Ailus126100.00%1100.00%
Total126100.00%1100.00%

/* * pipeline_pm_power - Apply power change to all entities in a pipeline * @entity: The entity * @change: Use count change * * Walk the pipeline to update the use count and the power state of all non-node * entities. * * Return 0 on success or a negative error code on failure. */
static int pipeline_pm_power(struct media_entity *entity, int change, struct media_graph *graph) { struct media_entity *first = entity; int ret = 0; if (!change) return 0; media_graph_walk_start(graph, entity); while (!ret && (entity = media_graph_walk_next(graph))) if (is_media_entity_v4l2_subdev(entity)) ret = pipeline_pm_power_one(entity, change); if (!ret) return ret; media_graph_walk_start(graph, first); while ((first = media_graph_walk_next(graph)) && first != entity) if (is_media_entity_v4l2_subdev(first)) pipeline_pm_power_one(first, -change); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Sakari Ailus124100.00%2100.00%
Total124100.00%2100.00%


int v4l2_pipeline_pm_use(struct media_entity *entity, int use) { struct media_device *mdev = entity->graph_obj.mdev; int change = use ? 1 : -1; int ret; mutex_lock(&mdev->graph_mutex); /* Apply use count to node. */ entity->use_count += change; WARN_ON(entity->use_count < 0); /* Apply power change to connected non-nodes. */ ret = pipeline_pm_power(entity, change, &mdev->pm_count_walk); if (ret < 0) entity->use_count -= change; mutex_unlock(&mdev->graph_mutex); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Sakari Ailus99100.00%1100.00%
Total99100.00%1100.00%

EXPORT_SYMBOL_GPL(v4l2_pipeline_pm_use);
int v4l2_pipeline_link_notify(struct media_link *link, u32 flags, unsigned int notification) { struct media_graph *graph = &link->graph_obj.mdev->pm_count_walk; struct media_entity *source = link->source->entity; struct media_entity *sink = link->sink->entity; int source_use; int sink_use; int ret = 0; source_use = pipeline_pm_use_count(source, graph); sink_use = pipeline_pm_use_count(sink, graph); if (notification == MEDIA_DEV_NOTIFY_POST_LINK_CH && !(flags & MEDIA_LNK_FL_ENABLED)) { /* Powering off entities is assumed to never fail. */ pipeline_pm_power(source, -sink_use, graph); pipeline_pm_power(sink, -source_use, graph); return 0; } if (notification == MEDIA_DEV_NOTIFY_PRE_LINK_CH && (flags & MEDIA_LNK_FL_ENABLED)) { ret = pipeline_pm_power(source, sink_use, graph); if (ret < 0) return ret; ret = pipeline_pm_power(sink, source_use, graph); if (ret < 0) pipeline_pm_power(source, -sink_use, graph); } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Sakari Ailus185100.00%2100.00%
Total185100.00%2100.00%

EXPORT_SYMBOL_GPL(v4l2_pipeline_link_notify);

Overall Contributors

PersonTokensPropCommitsCommitProp
Sakari Ailus62044.83%225.00%
Mauro Carvalho Chehab54439.33%225.00%
Shuah Khan21815.76%337.50%
Laurent Pinchart10.07%112.50%
Total1383100.00%8100.00%
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