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/bitops.h>
  27#include <linux/kernel.h>
  28#include <linux/list.h>
  29#include <linux/media.h>
  30
  31struct media_pipeline {
  32};
  33
  34struct media_link {
  35        struct media_pad *source;       /* Source pad */
  36        struct media_pad *sink;         /* Sink pad  */
  37        struct media_link *reverse;     /* Link in the reverse direction */
  38        unsigned long flags;            /* Link flags (MEDIA_LNK_FL_*) */
  39};
  40
  41struct media_pad {
  42        struct media_entity *entity;    /* Entity this pad belongs to */
  43        u16 index;                      /* Pad index in the entity pads array */
  44        unsigned long flags;            /* Pad flags (MEDIA_PAD_FL_*) */
  45};
  46
  47struct media_entity_operations {
  48        int (*link_setup)(struct media_entity *entity,
  49                          const struct media_pad *local,
  50                          const struct media_pad *remote, u32 flags);
  51        int (*link_validate)(struct media_link *link);
  52};
  53
  54struct media_entity {
  55        struct list_head list;
  56        struct media_device *parent;    /* Media device this entity belongs to*/
  57        u32 id;                         /* Entity ID, unique in the parent media
  58                                         * device context */
  59        const char *name;               /* Entity name */
  60        u32 type;                       /* Entity type (MEDIA_ENT_T_*) */
  61        u32 revision;                   /* Entity revision, driver specific */
  62        unsigned long flags;            /* Entity flags (MEDIA_ENT_FL_*) */
  63        u32 group_id;                   /* Entity group ID */
  64
  65        u16 num_pads;                   /* Number of sink and source pads */
  66        u16 num_links;                  /* Number of existing links, both
  67                                         * enabled and disabled */
  68        u16 num_backlinks;              /* Number of backlinks */
  69        u16 max_links;                  /* Maximum number of links */
  70
  71        struct media_pad *pads;         /* Pads array (num_pads elements) */
  72        struct media_link *links;       /* Links array (max_links elements)*/
  73
  74        const struct media_entity_operations *ops;      /* Entity operations */
  75
  76        /* Reference counts must never be negative, but are signed integers on
  77         * purpose: a simple WARN_ON(<0) check can be used to detect reference
  78         * count bugs that would make them negative.
  79         */
  80        int stream_count;               /* Stream count for the entity. */
  81        int use_count;                  /* Use count for the entity. */
  82
  83        struct media_pipeline *pipe;    /* Pipeline this entity belongs to. */
  84
  85        union {
  86                /* Node specifications */
  87                struct {
  88                        u32 major;
  89                        u32 minor;
  90                } v4l;
  91                struct {
  92                        u32 major;
  93                        u32 minor;
  94                } fb;
  95                struct {
  96                        u32 card;
  97                        u32 device;
  98                        u32 subdevice;
  99                } alsa;
 100                int dvb;
 101
 102                /* Sub-device specifications */
 103                /* Nothing needed yet */
 104        } info;
 105};
 106
 107static inline u32 media_entity_type(struct media_entity *entity)
 108{
 109        return entity->type & MEDIA_ENT_TYPE_MASK;
 110}
 111
 112static inline u32 media_entity_subtype(struct media_entity *entity)
 113{
 114        return entity->type & MEDIA_ENT_SUBTYPE_MASK;
 115}
 116
 117#define MEDIA_ENTITY_ENUM_MAX_DEPTH     16
 118#define MEDIA_ENTITY_ENUM_MAX_ID        64
 119
 120struct media_entity_graph {
 121        struct {
 122                struct media_entity *entity;
 123                int link;
 124        } stack[MEDIA_ENTITY_ENUM_MAX_DEPTH];
 125
 126        DECLARE_BITMAP(entities, MEDIA_ENTITY_ENUM_MAX_ID);
 127        int top;
 128};
 129
 130int media_entity_init(struct media_entity *entity, u16 num_pads,
 131                struct media_pad *pads, u16 extra_links);
 132void media_entity_cleanup(struct media_entity *entity);
 133
 134int media_entity_create_link(struct media_entity *source, u16 source_pad,
 135                struct media_entity *sink, u16 sink_pad, u32 flags);
 136void __media_entity_remove_links(struct media_entity *entity);
 137void media_entity_remove_links(struct media_entity *entity);
 138
 139int __media_entity_setup_link(struct media_link *link, u32 flags);
 140int media_entity_setup_link(struct media_link *link, u32 flags);
 141struct media_link *media_entity_find_link(struct media_pad *source,
 142                struct media_pad *sink);
 143struct media_pad *media_entity_remote_pad(struct media_pad *pad);
 144
 145struct media_entity *media_entity_get(struct media_entity *entity);
 146void media_entity_put(struct media_entity *entity);
 147
 148void media_entity_graph_walk_start(struct media_entity_graph *graph,
 149                struct media_entity *entity);
 150struct media_entity *
 151media_entity_graph_walk_next(struct media_entity_graph *graph);
 152__must_check int media_entity_pipeline_start(struct media_entity *entity,
 153                                             struct media_pipeline *pipe);
 154void media_entity_pipeline_stop(struct media_entity *entity);
 155
 156#define media_entity_call(entity, operation, args...)                   \
 157        (((entity)->ops && (entity)->ops->operation) ?                  \
 158         (entity)->ops->operation((entity) , ##args) : -ENOIOCTLCMD)
 159
 160#endif
 161