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 31 struct media_pipeline { 32 }; 33 34 struct 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 41 struct 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 47 /** 48 * struct media_entity_operations - Media entity operations 49 * @link_setup: Notify the entity of link changes. The operation can 50 * return an error, in which case link setup will be 51 * cancelled. Optional. 52 * @link_validate: Return whether a link is valid from the entity point of 53 * view. The media_entity_pipeline_start() function 54 * validates all links by calling this operation. Optional. 55 */ 56 struct media_entity_operations { 57 int (*link_setup)(struct media_entity *entity, 58 const struct media_pad *local, 59 const struct media_pad *remote, u32 flags); 60 int (*link_validate)(struct media_link *link); 61 }; 62 63 struct media_entity { 64 struct list_head list; 65 struct media_device *parent; /* Media device this entity belongs to*/ 66 u32 id; /* Entity ID, unique in the parent media 67 * device context */ 68 const char *name; /* Entity name */ 69 u32 type; /* Entity type (MEDIA_ENT_T_*) */ 70 u32 revision; /* Entity revision, driver specific */ 71 unsigned long flags; /* Entity flags (MEDIA_ENT_FL_*) */ 72 u32 group_id; /* Entity group ID */ 73 74 u16 num_pads; /* Number of sink and source pads */ 75 u16 num_links; /* Number of existing links, both 76 * enabled and disabled */ 77 u16 num_backlinks; /* Number of backlinks */ 78 u16 max_links; /* Maximum number of links */ 79 80 struct media_pad *pads; /* Pads array (num_pads elements) */ 81 struct media_link *links; /* Links array (max_links elements)*/ 82 83 const struct media_entity_operations *ops; /* Entity operations */ 84 85 /* Reference counts must never be negative, but are signed integers on 86 * purpose: a simple WARN_ON(<0) check can be used to detect reference 87 * count bugs that would make them negative. 88 */ 89 int stream_count; /* Stream count for the entity. */ 90 int use_count; /* Use count for the entity. */ 91 92 struct media_pipeline *pipe; /* Pipeline this entity belongs to. */ 93 94 union { 95 /* Node specifications */ 96 struct { 97 u32 major; 98 u32 minor; 99 } dev; 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 160