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