LXR linux/include/media/media-entity.h

   1/*
   2 * Media entity
   3 *
   4 * Copyright (C) 2010 Nokia Corporation
   5 *
   6 * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
   7 *           Sakari Ailus <sakari.ailus@iki.fi>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with this program; if not, write to the Free Software
  20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21 */
  22
  23#ifndef _MEDIA_ENTITY_H
  24#define _MEDIA_ENTITY_H
  25
  26#include <linux/list.h>
  27#include <linux/media.h>
  28
  29struct media_pipeline {
  30};
  31
  32struct media_link {
  33        struct media_pad *source;       /* Source pad */
  34        struct media_pad *sink;         /* Sink pad  */
  35        struct media_link *reverse;     /* Link in the reverse direction */
  36        unsigned long flags;            /* Link flags (MEDIA_LNK_FL_*) */
  37};
  38
  39struct media_pad {
  40        struct media_entity *entity;    /* Entity this pad belongs to */
  41        u16 index;                      /* Pad index in the entity pads array */
  42        unsigned long flags;            /* Pad flags (MEDIA_PAD_FL_*) */
  43};
  44
  45struct media_entity_operations {
  46        int (*link_setup)(struct media_entity *entity,
  47                          const struct media_pad *local,
  48                          const struct media_pad *remote, u32 flags);
  49        int (*link_validate)(struct media_link *link);
  50};
  51
  52struct media_entity {
  53        struct list_head list;
  54        struct media_device *parent;    /* Media device this entity belongs to*/
  55        u32 id;                         /* Entity ID, unique in the parent media
  56                                         * device context */
  57        const char *name;               /* Entity name */
  58        u32 type;                       /* Entity type (MEDIA_ENT_T_*) */
  59        u32 revision;                   /* Entity revision, driver specific */
  60        unsigned long flags;            /* Entity flags (MEDIA_ENT_FL_*) */
  61        u32 group_id;                   /* Entity group ID */
  62
  63        u16 num_pads;                   /* Number of sink and source pads */
  64        u16 num_links;                  /* Number of existing links, both
  65                                         * enabled and disabled */
  66        u16 num_backlinks;              /* Number of backlinks */
  67        u16 max_links;                  /* Maximum number of links */
  68
  69        struct media_pad *pads;         /* Pads array (num_pads elements) */
  70        struct media_link *links;       /* Links array (max_links elements)*/
  71
  72        const struct media_entity_operations *ops;      /* Entity operations */
  73
  74        /* Reference counts must never be negative, but are signed integers on
  75         * purpose: a simple WARN_ON(<0) check can be used to detect reference
  76         * count bugs that would make them negative.
  77         */
  78        int stream_count;               /* Stream count for the entity. */
  79        int use_count;                  /* Use count for the entity. */
  80
  81        struct media_pipeline *pipe;    /* Pipeline this entity belongs to. */
  82
  83        union {
  84                /* Node specifications */
  85                struct {
  86                        u32 major;
  87                        u32 minor;
  88                } v4l;
  89                struct {
  90                        u32 major;
  91                        u32 minor;
  92                } fb;
  93                struct {
  94                        u32 card;
  95                        u32 device;
  96                        u32 subdevice;
  97                } alsa;
  98                int dvb;
  99
 100                /* Sub-device specifications */
 101                /* Nothing needed yet */
 102        } info;
 103};
 104
 105static inline u32 media_entity_type(struct media_entity *entity)
 106{
 107        return entity->type & MEDIA_ENT_TYPE_MASK;
 108}
 109
 110static inline u32 media_entity_subtype(struct media_entity *entity)
 111{
 112        return entity->type & MEDIA_ENT_SUBTYPE_MASK;
 113}
 114
 115#define MEDIA_ENTITY_ENUM_MAX_DEPTH     16
 116
 117struct media_entity_graph {
 118        struct {
 119                struct media_entity *entity;
 120                int link;
 121        } stack[MEDIA_ENTITY_ENUM_MAX_DEPTH];
 122        int top;
 123};
 124
 125int media_entity_init(struct media_entity *entity, u16 num_pads,
 126                struct media_pad *pads, u16 extra_links);
 127void media_entity_cleanup(struct media_entity *entity);
 128
 129int media_entity_create_link(struct media_entity *source, u16 source_pad,
 130                struct media_entity *sink, u16 sink_pad, u32 flags);
 131int __media_entity_setup_link(struct media_link *link, u32 flags);
 132int media_entity_setup_link(struct media_link *link, u32 flags);
 133struct media_link *media_entity_find_link(struct media_pad *source,
 134                struct media_pad *sink);
 135struct media_pad *media_entity_remote_source(struct media_pad *pad);
 136
 137struct media_entity *media_entity_get(struct media_entity *entity);
 138void media_entity_put(struct media_entity *entity);
 139
 140void media_entity_graph_walk_start(struct media_entity_graph *graph,
 141                struct media_entity *entity);
 142struct media_entity *
 143media_entity_graph_walk_next(struct media_entity_graph *graph);
 144__must_check int media_entity_pipeline_start(struct media_entity *entity,
 145                                             struct media_pipeline *pipe);
 146void media_entity_pipeline_stop(struct media_entity *entity);
 147
 148#define media_entity_call(entity, operation, args...)                   \
 149        (((entity)->ops && (entity)->ops->operation) ?                  \
 150         (entity)->ops->operation((entity) , ##args) : -ENOIOCTLCMD)
 151
 152#endif
 153