projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 176fb0d1 LP |
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 | #include <linux/types.h> | |
| 24 | #include <linux/ioctl.h> | |
| 25 | ||
| 26 | #include <media/media-device.h> | |
| 27 | #include <media/media-devnode.h> | |
| 53e269c1 | 28 | #include <media/media-entity.h> |
| 176fb0d1 LP |
29 | |
| 30 | static const struct media_file_operations media_device_fops = { | |
| 31 | .owner = THIS_MODULE, | |
| 32 | }; | |
| 33 | ||
| 34 | /* ----------------------------------------------------------------------------- | |
| 35 | * sysfs | |
| 36 | */ | |
| 37 | ||
| 38 | static ssize_t show_model(struct device *cd, | |
| 39 | struct device_attribute *attr, char *buf) | |
| 40 | { | |
| 41 | struct media_device *mdev = to_media_device(to_media_devnode(cd)); | |
| 42 | ||
| 43 | return sprintf(buf, "%.*s\n", (int)sizeof(mdev->model), mdev->model); | |
| 44 | } | |
| 45 | ||
| 46 | static DEVICE_ATTR(model, S_IRUGO, show_model, NULL); | |
| 47 | ||
| 48 | /* ----------------------------------------------------------------------------- | |
| 49 | * Registration/unregistration | |
| 50 | */ | |
| 51 | ||
| 52 | static void media_device_release(struct media_devnode *mdev) | |
| 53 | { | |
| 54 | } | |
| 55 | ||
| 56 | /** | |
| 57 | * media_device_register - register a media device | |
| 58 | * @mdev: The media device | |
| 59 | * | |
| 60 | * The caller is responsible for initializing the media device before | |
| 61 | * registration. The following fields must be set: | |
| 62 | * | |
| 63 | * - dev must point to the parent device | |
| 64 | * - model must be filled with the device model name | |
| 65 | */ | |
| 66 | int __must_check media_device_register(struct media_device *mdev) | |
| 67 | { | |
| 68 | int ret; | |
| 69 | ||
| 70 | if (WARN_ON(mdev->dev == NULL || mdev->model[0] == 0)) | |
| 71 | return -EINVAL; | |
| 72 | ||
| 53e269c1 LP |
73 | mdev->entity_id = 1; |
| 74 | INIT_LIST_HEAD(&mdev->entities); | |
| 75 | spin_lock_init(&mdev->lock); | |
| 76 | ||
| 176fb0d1 LP |
77 | /* Register the device node. */ |
| 78 | mdev->devnode.fops = &media_device_fops; | |
| 79 | mdev->devnode.parent = mdev->dev; | |
| 80 | mdev->devnode.release = media_device_release; | |
| 81 | ret = media_devnode_register(&mdev->devnode); | |
| 82 | if (ret < 0) | |
| 83 | return ret; | |
| 84 | ||
| 85 | ret = device_create_file(&mdev->devnode.dev, &dev_attr_model); | |
| 86 | if (ret < 0) { | |
| 87 | media_devnode_unregister(&mdev->devnode); | |
| 88 | return ret; | |
| 89 | } | |
| 90 | ||
| 91 | return 0; | |
| 92 | } | |
| 93 | EXPORT_SYMBOL_GPL(media_device_register); | |
| 94 | ||
| 95 | /** | |
| 96 | * media_device_unregister - unregister a media device | |
| 97 | * @mdev: The media device | |
| 98 | * | |
| 99 | */ | |
| 100 | void media_device_unregister(struct media_device *mdev) | |
| 101 | { | |
| 53e269c1 LP |
102 | struct media_entity *entity; |
| 103 | struct media_entity *next; | |
| 104 | ||
| 105 | list_for_each_entry_safe(entity, next, &mdev->entities, list) | |
| 106 | media_device_unregister_entity(entity); | |
| 107 | ||
| 176fb0d1 LP |
108 | device_remove_file(&mdev->devnode.dev, &dev_attr_model); |
| 109 | media_devnode_unregister(&mdev->devnode); | |
| 110 | } | |
| 111 | EXPORT_SYMBOL_GPL(media_device_unregister); | |
| 53e269c1 LP |
112 | |
| 113 | /** | |
| 114 | * media_device_register_entity - Register an entity with a media device | |
| 115 | * @mdev: The media device | |
| 116 | * @entity: The entity | |
| 117 | */ | |
| 118 | int __must_check media_device_register_entity(struct media_device *mdev, | |
| 119 | struct media_entity *entity) | |
| 120 | { | |
| 121 | /* Warn if we apparently re-register an entity */ | |
| 122 | WARN_ON(entity->parent != NULL); | |
| 123 | entity->parent = mdev; | |
| 124 | ||
| 125 | spin_lock(&mdev->lock); | |
| 126 | if (entity->id == 0) | |
| 127 | entity->id = mdev->entity_id++; | |
| 128 | else | |
| 129 | mdev->entity_id = max(entity->id + 1, mdev->entity_id); | |
| 130 | list_add_tail(&entity->list, &mdev->entities); | |
| 131 | spin_unlock(&mdev->lock); | |
| 132 | ||
| 133 | return 0; | |
| 134 | } | |
| 135 | EXPORT_SYMBOL_GPL(media_device_register_entity); | |
| 136 | ||
| 137 | /** | |
| 138 | * media_device_unregister_entity - Unregister an entity | |
| 139 | * @entity: The entity | |
| 140 | * | |
| 141 | * If the entity has never been registered this function will return | |
| 142 | * immediately. | |
| 143 | */ | |
| 144 | void media_device_unregister_entity(struct media_entity *entity) | |
| 145 | { | |
| 146 | struct media_device *mdev = entity->parent; | |
| 147 | ||
| 148 | if (mdev == NULL) | |
| 149 | return; | |
| 150 | ||
| 151 | spin_lock(&mdev->lock); | |
| 152 | list_del(&entity->list); | |
| 153 | spin_unlock(&mdev->lock); | |
| 154 | entity->parent = NULL; | |
| 155 | } | |
| 156 | EXPORT_SYMBOL_GPL(media_device_unregister_entity); |