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	} else
 97		ret = 0;
 98
 99	return ret;
100}
101
102int uvc_mc_register_entities(struct uvc_video_chain *chain)
103{
104	struct uvc_entity *entity;
105	int ret;
106
107	list_for_each_entry(entity, &chain->entities, chain) {
108		ret = uvc_mc_init_entity(entity);
109		if (ret < 0) {
110			uvc_printk(KERN_INFO, "Failed to initialize entity for "
111				   "entity %u\n", entity->id);
112			return ret;
113		}
114	}
115
116	list_for_each_entry(entity, &chain->entities, chain) {
117		ret = uvc_mc_register_entity(chain, entity);
118		if (ret < 0) {
119			uvc_printk(KERN_INFO, "Failed to register entity for "
120				   "entity %u\n", entity->id);
121			return ret;
122		}
123	}
124
125	return 0;
126}