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