LXR linux/drivers/media/usb/uvc/uvc

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *      uvc_entity.c  --  USB Video Class driver
   4 *
   5 *      Copyright (C) 2005-2011
   6 *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
   7 */
   8
   9#include <linux/kernel.h>
  10#include <linux/list.h>
  11#include <linux/videodev2.h>
  12
  13#include <media/v4l2-common.h>
  14
  15#include "uvcvideo.h"
  16
  17static int uvc_mc_create_links(struct uvc_video_chain *chain,
  18                                    struct uvc_entity *entity)
  19{
  20        const u32 flags = MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE;
  21        struct media_entity *sink;
  22        unsigned int i;
  23        int ret;
  24
  25        sink = (UVC_ENTITY_TYPE(entity) == UVC_TT_STREAMING)
  26             ? (entity->vdev ? &entity->vdev->entity : NULL)
  27             : &entity->subdev.entity;
  28        if (sink == NULL)
  29                return 0;
  30
  31        for (i = 0; i < entity->num_pads; ++i) {
  32                struct media_entity *source;
  33                struct uvc_entity *remote;
  34                u8 remote_pad;
  35
  36                if (!(entity->pads[i].flags & MEDIA_PAD_FL_SINK))
  37                        continue;
  38
  39                remote = uvc_entity_by_id(chain->dev, entity->baSourceID[i]);
  40                if (remote == NULL)
  41                        return -EINVAL;
  42
  43                source = (UVC_ENTITY_TYPE(remote) == UVC_TT_STREAMING)
  44                       ? (remote->vdev ? &remote->vdev->entity : NULL)
  45                       : &remote->subdev.entity;
  46                if (source == NULL)
  47                        continue;
  48
  49                remote_pad = remote->num_pads - 1;
  50                ret = media_create_pad_link(source, remote_pad,
  51                                               sink, i, flags);
  52                if (ret < 0)
  53                        return ret;
  54        }
  55
  56        return 0;
  57}
  58
  59static const struct v4l2_subdev_ops uvc_subdev_ops = {
  60};
  61
  62void uvc_mc_cleanup_entity(struct uvc_entity *entity)
  63{
  64        if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING)
  65                media_entity_cleanup(&entity->subdev.entity);
  66        else if (entity->vdev != NULL)
  67                media_entity_cleanup(&entity->vdev->entity);
  68}
  69
  70static int uvc_mc_init_entity(struct uvc_video_chain *chain,
  71                              struct uvc_entity *entity)
  72{
  73        int ret;
  74
  75        if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING) {
  76                v4l2_subdev_init(&entity->subdev, &uvc_subdev_ops);
  77                strscpy(entity->subdev.name, entity->name,
  78                        sizeof(entity->subdev.name));
  79
  80                ret = media_entity_pads_init(&entity->subdev.entity,
  81                                        entity->num_pads, entity->pads);
  82
  83                if (ret < 0)
  84                        return ret;
  85
  86                ret = v4l2_device_register_subdev(&chain->dev->vdev,
  87                                                  &entity->subdev);
  88        } else if (entity->vdev != NULL) {
  89                ret = media_entity_pads_init(&entity->vdev->entity,
  90                                        entity->num_pads, entity->pads);
  91                if (entity->flags & UVC_ENTITY_FLAG_DEFAULT)
  92                        entity->vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
  93        } else
  94                ret = 0;
  95
  96        return ret;
  97}
  98
  99int uvc_mc_register_entities(struct uvc_video_chain *chain)
 100{
 101        struct uvc_entity *entity;
 102        int ret;
 103
 104        list_for_each_entry(entity, &chain->entities, chain) {
 105                ret = uvc_mc_init_entity(chain, entity);
 106                if (ret < 0) {
 107                        uvc_printk(KERN_INFO, "Failed to initialize entity for "
 108                                   "entity %u\n", entity->id);
 109                        return ret;
 110                }
 111        }
 112
 113        list_for_each_entry(entity, &chain->entities, chain) {
 114                ret = uvc_mc_create_links(chain, entity);
 115                if (ret < 0) {
 116                        uvc_printk(KERN_INFO, "Failed to create links for "
 117                                   "entity %u\n", entity->id);
 118                        return ret;
 119                }
 120        }
 121
 122        return 0;
 123}
 124