xref: /openbmc/linux/include/media/media-entity.h (revision 37be287c)
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 struct media_entity_operations {
48 	int (*link_setup)(struct media_entity *entity,
49 			  const struct media_pad *local,
50 			  const struct media_pad *remote, u32 flags);
51 	int (*link_validate)(struct media_link *link);
52 };
53 
54 struct media_entity {
55 	struct list_head list;
56 	struct media_device *parent;	/* Media device this entity belongs to*/
57 	u32 id;				/* Entity ID, unique in the parent media
58 					 * device context */
59 	const char *name;		/* Entity name */
60 	u32 type;			/* Entity type (MEDIA_ENT_T_*) */
61 	u32 revision;			/* Entity revision, driver specific */
62 	unsigned long flags;		/* Entity flags (MEDIA_ENT_FL_*) */
63 	u32 group_id;			/* Entity group ID */
64 
65 	u16 num_pads;			/* Number of sink and source pads */
66 	u16 num_links;			/* Number of existing links, both
67 					 * enabled and disabled */
68 	u16 num_backlinks;		/* Number of backlinks */
69 	u16 max_links;			/* Maximum number of links */
70 
71 	struct media_pad *pads;		/* Pads array (num_pads elements) */
72 	struct media_link *links;	/* Links array (max_links elements)*/
73 
74 	const struct media_entity_operations *ops;	/* Entity operations */
75 
76 	/* Reference counts must never be negative, but are signed integers on
77 	 * purpose: a simple WARN_ON(<0) check can be used to detect reference
78 	 * count bugs that would make them negative.
79 	 */
80 	int stream_count;		/* Stream count for the entity. */
81 	int use_count;			/* Use count for the entity. */
82 
83 	struct media_pipeline *pipe;	/* Pipeline this entity belongs to. */
84 
85 	union {
86 		/* Node specifications */
87 		struct {
88 			u32 major;
89 			u32 minor;
90 		} v4l;
91 		struct {
92 			u32 major;
93 			u32 minor;
94 		} fb;
95 		struct {
96 			u32 card;
97 			u32 device;
98 			u32 subdevice;
99 		} alsa;
100 		int dvb;
101 
102 		/* Sub-device specifications */
103 		/* Nothing needed yet */
104 	} info;
105 };
106 
107 static inline u32 media_entity_type(struct media_entity *entity)
108 {
109 	return entity->type & MEDIA_ENT_TYPE_MASK;
110 }
111 
112 static inline u32 media_entity_subtype(struct media_entity *entity)
113 {
114 	return entity->type & MEDIA_ENT_SUBTYPE_MASK;
115 }
116 
117 #define MEDIA_ENTITY_ENUM_MAX_DEPTH	16
118 #define MEDIA_ENTITY_ENUM_MAX_ID	64
119 
120 struct media_entity_graph {
121 	struct {
122 		struct media_entity *entity;
123 		int link;
124 	} stack[MEDIA_ENTITY_ENUM_MAX_DEPTH];
125 
126 	DECLARE_BITMAP(entities, MEDIA_ENTITY_ENUM_MAX_ID);
127 	int top;
128 };
129 
130 int media_entity_init(struct media_entity *entity, u16 num_pads,
131 		struct media_pad *pads, u16 extra_links);
132 void media_entity_cleanup(struct media_entity *entity);
133 
134 int media_entity_create_link(struct media_entity *source, u16 source_pad,
135 		struct media_entity *sink, u16 sink_pad, u32 flags);
136 void __media_entity_remove_links(struct media_entity *entity);
137 void media_entity_remove_links(struct media_entity *entity);
138 
139 int __media_entity_setup_link(struct media_link *link, u32 flags);
140 int media_entity_setup_link(struct media_link *link, u32 flags);
141 struct media_link *media_entity_find_link(struct media_pad *source,
142 		struct media_pad *sink);
143 struct media_pad *media_entity_remote_pad(struct media_pad *pad);
144 
145 struct media_entity *media_entity_get(struct media_entity *entity);
146 void media_entity_put(struct media_entity *entity);
147 
148 void media_entity_graph_walk_start(struct media_entity_graph *graph,
149 		struct media_entity *entity);
150 struct media_entity *
151 media_entity_graph_walk_next(struct media_entity_graph *graph);
152 __must_check int media_entity_pipeline_start(struct media_entity *entity,
153 					     struct media_pipeline *pipe);
154 void media_entity_pipeline_stop(struct media_entity *entity);
155 
156 #define media_entity_call(entity, operation, args...)			\
157 	(((entity)->ops && (entity)->ops->operation) ?			\
158 	 (entity)->ops->operation((entity) , ##args) : -ENOIOCTLCMD)
159 
160 #endif
161