include/media/media-device.h

   1 /*
   2  * Media device
   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_DEVICE_H
  24 #define _MEDIA_DEVICE_H
  25
  26 #include <linux/list.h>
  27 #include <linux/mutex.h>
  28 #include <linux/spinlock.h>
  29
  30 #include <media/media-devnode.h>
  31 #include <media/media-entity.h>
  32
  33 struct device;
  34
  35 /**
  36  * struct media_device - Media device
  37  * @dev:        Parent device
  38  * @devnode:    Media device node
  39  * @model:      Device model name
  40  * @serial:     Device serial number (optional)
  41  * @bus_info:   Unique and stable device location identifier
  42  * @hw_revision: Hardware device revision
  43  * @driver_version: Device driver version
  44  * @entity_id:  ID of the next entity to be registered
  45  * @entities:   List of registered entities
  46  * @lock:       Entities list lock
  47  * @graph_mutex: Entities graph operation lock
  48  * @link_notify: Link state change notification callback
  49  *
  50  * This structure represents an abstract high-level media device. It allows easy
  51  * access to entities and provides basic media device-level support. The
  52  * structure can be allocated directly or embedded in a larger structure.
  53  *
  54  * The parent @dev is a physical device. It must be set before registering the
  55  * media device.
  56  *
  57  * @model is a descriptive model name exported through sysfs. It doesn't have to
  58  * be unique.
  59  */
  60 struct media_device {
  61         /* dev->driver_data points to this struct. */
  62         struct device *dev;
  63         struct media_devnode devnode;
  64
  65         char model[32];
  66         char serial[40];
  67         char bus_info[32];
  68         u32 hw_revision;
  69         u32 driver_version;
  70
  71         u32 entity_id;
  72         struct list_head entities;
  73
  74         /* Protects the entities list */
  75         spinlock_t lock;
  76         /* Serializes graph operations. */
  77         struct mutex graph_mutex;
  78
  79         int (*link_notify)(struct media_link *link, u32 flags,
  80                            unsigned int notification);
  81 };
  82
  83 /* Supported link_notify @notification values. */
  84 #define MEDIA_DEV_NOTIFY_PRE_LINK_CH    0
  85 #define MEDIA_DEV_NOTIFY_POST_LINK_CH   1
  86
  87 /* media_devnode to media_device */
  88 #define to_media_device(node) container_of(node, struct media_device, devnode)
  89
  90 int __must_check media_device_register(struct media_device *mdev);
  91 void media_device_unregister(struct media_device *mdev);
  92
  93 int __must_check media_device_register_entity(struct media_device *mdev,
  94                                               struct media_entity *entity);
  95 void media_device_unregister_entity(struct media_entity *entity);
  96
  97 /* Iterate over all entities. */
  98 #define media_device_for_each_entity(entity, mdev)                      \
  99         list_for_each_entry(entity, &(mdev)->entities, list)
 100
 101 #endif