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
  22/* ------------------------------------------------------------------------
  23 * Video subdevices registration and unregistration
  24 */
  25
  26static int uvc_mc_register_entity(struct uvc_video_chain *chain,
  27        struct uvc_entity *entity)
  28{
  29        const u32 flags = MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE;
  30        struct media_entity *sink;
  31        unsigned int i;
  32        int ret;
  33
  34        sink = (UVC_ENTITY_TYPE(entity) == UVC_TT_STREAMING)
  35             ? (entity->vdev ? &entity->vdev->entity : NULL)
  36             : &entity->subdev.entity;
  37        if (sink == NULL)
  38                return 0;
  39
  40        for (i = 0; i < entity->num_pads; ++i) {
  41                struct media_entity *source;
  42                struct uvc_entity *remote;
  43                u8 remote_pad;
  44
  45                if (!(entity->pads[i].flags & MEDIA_PAD_FL_SINK))
  46                        continue;
  47
  48                remote = uvc_entity_by_id(chain->dev, entity->baSourceID[i]);
  49                if (remote == NULL)
  50                        return -EINVAL;
  51
  52                source = (UVC_ENTITY_TYPE(remote) == UVC_TT_STREAMING)
  53                       ? (remote->vdev ? &remote->vdev->entity : NULL)
  54                       : &remote->subdev.entity;
  55                if (source == NULL)
  56                        continue;
  57
  58                remote_pad = remote->num_pads - 1;
  59                ret = media_entity_create_link(source, remote_pad,
  60                                               sink, i, flags);
  61                if (ret < 0)
  62                        return ret;
  63        }
  64
  65        if (UVC_ENTITY_TYPE(entity) == UVC_TT_STREAMING)
  66                return 0;
  67
  68        return v4l2_device_register_subdev(&chain->dev->vdev, &entity->subdev);
  69}
  70
  71static struct v4l2_subdev_ops uvc_subdev_ops = {
  72};
  73
  74void uvc_mc_cleanup_entity(struct uvc_entity *entity)
  75{
  76        if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING)
  77                media_entity_cleanup(&entity->subdev.entity);
  78        else if (entity->vdev != NULL)
  79                media_entity_cleanup(&entity->vdev->entity);
  80}
  81
  82static int uvc_mc_init_entity(struct uvc_entity *entity)
  83{
  84        int ret;
  85
  86        if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING) {
  87                v4l2_subdev_init(&entity->subdev, &uvc_subdev_ops);
  88                strlcpy(entity->subdev.name, entity->name,
  89                        sizeof(entity->subdev.name));
  90
  91                ret = media_entity_init(&entity->subdev.entity,
  92                                        entity->num_pads, entity->pads, 0);
  93        } else if (entity->vdev != NULL) {
  94                ret = media_entity_init(&entity->vdev->entity,
  95                                        entity->num_pads, entity->pads, 0);
  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(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_register_entity(chain, entity);
 120                if (ret < 0) {
 121                        uvc_printk(KERN_INFO, "Failed to register entity for "
 122                                   "entity %u\n", entity->id);
 123                        return ret;
 124                }
 125        }
 126
 127        return 0;
 128}
 129