xref: /openbmc/linux/include/media/media-entity.h (revision 63dc02bd)
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
152