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

   1/*
   2 *      uvc_entity.c  --  USB Video Class driver
   3 *
   4 *      Copyright (C) 2005-2011
   5 *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
   6 *
   7 *      This program is free software; you can redistribute it and/or modify
   8 *      it under the terms of the GNU General Public License as published by
   9 *      the Free Software Foundation; either version 2 of the License, or
  10 *      (at your option) any later version.
  11 *
  12 */
  13
  14#include <linux/kernel.h>
  15#include <linux/list.h>
  16#include <linux/videodev2.h>
  17
  18#include <media/v4l2-common.h>
  19
  20#include "uvcvideo.h"
  21
  22static int uvc_mc_create_links(struct uvc_video_chain *chain,
  23                                    struct uvc_entity *entity)
  24{
  25        const u32 flags = MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE;
  26        struct media_entity *sink;
  27        unsigned int i;
  28        int ret;
  29
  30        sink = (UVC_ENTITY_TYPE(entity) == UVC_TT_STREAMING)
  31             ? (entity->vdev ? &entity->vdev->entity : NULL)
  32             : &entity->subdev.entity;
  33        if (sink == NULL)
  34                return 0;
  35
  36        for (i = 0; i < entity->num_pads; ++i) {
  37                struct media_entity *source;
  38                struct uvc_entity *remote;
  39                u8 remote_pad;
  40
  41                if (!(entity->pads[i].flags & MEDIA_PAD_FL_SINK))
  42                        continue;
  43
  44                remote = uvc_entity_by_id(chain->dev, entity->baSourceID[i]);
  45                if (remote == NULL)
  46                        return -EINVAL;
  47
  48                source = (UVC_ENTITY_TYPE(remote) == UVC_TT_STREAMING)
  49                       ? (remote->vdev ? &remote->vdev->entity : NULL)
  50                       : &remote->subdev.entity;
  51                if (source == NULL)
  52                        continue;
  53
  54                remote_pad = remote->num_pads - 1;
  55                ret = media_create_pad_link(source, remote_pad,
  56                                               sink, i, flags);
  57                if (ret < 0)
  58                        return ret;
  59        }
  60
  61        return 0;
  62}
  63
  64static const struct v4l2_subdev_ops uvc_subdev_ops = {
  65};
  66
  67void uvc_mc_cleanup_entity(struct uvc_entity *entity)
  68{
  69        if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING)
  70                media_entity_cleanup(&entity->subdev.entity);
  71        else if (entity->vdev != NULL)
  72                media_entity_cleanup(&entity->vdev->entity);
  73}
  74
  75static int uvc_mc_init_entity(struct uvc_video_chain *chain,
  76                              struct uvc_entity *entity)
  77{
  78        int ret;
  79
  80        if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING) {
  81                v4l2_subdev_init(&entity->subdev, &uvc_subdev_ops);
  82                strlcpy(entity->subdev.name, entity->name,
  83                        sizeof(entity->subdev.name));
  84
  85                ret = media_entity_pads_init(&entity->subdev.entity,
  86                                        entity->num_pads, entity->pads);
  87
  88                if (ret < 0)
  89                        return ret;
  90
  91                ret = v4l2_device_register_subdev(&chain->dev->vdev,
  92                                                  &entity->subdev);
  93        } else if (entity->vdev != NULL) {
  94                ret = media_entity_pads_init(&entity->vdev->entity,
  95                                        entity->num_pads, entity->pads);
  96                if (entity->flags & UVC_ENTITY_FLAG_DEFAULT)
  97                        entity->vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
  98        } else
  99                ret = 0;
 100
 101        return ret;
 102}
 103
 104int uvc_mc_register_entities(struct uvc_video_chain *chain)
 105{
 106        struct uvc_entity *entity;
 107        int ret;
 108
 109        list_for_each_entry(entity, &chain->entities, chain) {
 110                ret = uvc_mc_init_entity(chain, entity);
 111                if (ret < 0) {
 112                        uvc_printk(KERN_INFO, "Failed to initialize entity for "
 113                                   "entity %u\n", entity->id);
 114                        return ret;
 115                }
 116        }
 117
 118        list_for_each_entry(entity, &chain->entities, chain) {
 119                ret = uvc_mc_create_links(chain, entity);
 120                if (ret < 0) {
 121                        uvc_printk(KERN_INFO, "Failed to create links for "
 122                                   "entity %u\n", entity->id);
 123                        return ret;
 124                }
 125        }
 126
 127        return 0;
 128}
 129