xref: /openbmc/linux/include/media/media-entity.h (revision 5104d265)
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 	int (*link_validate)(struct media_link *link);
50 };
51 
52 struct 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 
105 static inline u32 media_entity_type(struct media_entity *entity)
106 {
107 	return entity->type & MEDIA_ENT_TYPE_MASK;
108 }
109 
110 static 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 
117 struct 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 
125 int media_entity_init(struct media_entity *entity, u16 num_pads,
126 		struct media_pad *pads, u16 extra_links);
127 void media_entity_cleanup(struct media_entity *entity);
128 
129 int media_entity_create_link(struct media_entity *source, u16 source_pad,
130 		struct media_entity *sink, u16 sink_pad, u32 flags);
131 void __media_entity_remove_links(struct media_entity *entity);
132 void media_entity_remove_links(struct media_entity *entity);
133 
134 int __media_entity_setup_link(struct media_link *link, u32 flags);
135 int media_entity_setup_link(struct media_link *link, u32 flags);
136 struct media_link *media_entity_find_link(struct media_pad *source,
137 		struct media_pad *sink);
138 struct media_pad *media_entity_remote_pad(struct media_pad *pad);
139 
140 struct media_entity *media_entity_get(struct media_entity *entity);
141 void media_entity_put(struct media_entity *entity);
142 
143 void media_entity_graph_walk_start(struct media_entity_graph *graph,
144 		struct media_entity *entity);
145 struct media_entity *
146 media_entity_graph_walk_next(struct media_entity_graph *graph);
147 __must_check int media_entity_pipeline_start(struct media_entity *entity,
148 					     struct media_pipeline *pipe);
149 void media_entity_pipeline_stop(struct media_entity *entity);
150 
151 #define media_entity_call(entity, operation, args...)			\
152 	(((entity)->ops && (entity)->ops->operation) ?			\
153 	 (entity)->ops->operation((entity) , ##args) : -ENOIOCTLCMD)
154 
155 #endif
156