| Laurent Pinchart | 176fb0d | 2009-12-09 08:39:58 -0300 | [diff] [blame^] | 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> |
| 28 | |
| 29 | static const struct media_file_operations media_device_fops = { |
| 30 | .owner = THIS_MODULE, |
| 31 | }; |
| 32 | |
| 33 | /* ----------------------------------------------------------------------------- |
| 34 | * sysfs |
| 35 | */ |
| 36 | |
| 37 | static ssize_t show_model(struct device *cd, |
| 38 | struct device_attribute *attr, char *buf) |
| 39 | { |
| 40 | struct media_device *mdev = to_media_device(to_media_devnode(cd)); |
| 41 | |
| 42 | return sprintf(buf, "%.*s\n", (int)sizeof(mdev->model), mdev->model); |
| 43 | } |
| 44 | |
| 45 | static DEVICE_ATTR(model, S_IRUGO, show_model, NULL); |
| 46 | |
| 47 | /* ----------------------------------------------------------------------------- |
| 48 | * Registration/unregistration |
| 49 | */ |
| 50 | |
| 51 | static void media_device_release(struct media_devnode *mdev) |
| 52 | { |
| 53 | } |
| 54 | |
| 55 | /** |
| 56 | * media_device_register - register a media device |
| 57 | * @mdev: The media device |
| 58 | * |
| 59 | * The caller is responsible for initializing the media device before |
| 60 | * registration. The following fields must be set: |
| 61 | * |
| 62 | * - dev must point to the parent device |
| 63 | * - model must be filled with the device model name |
| 64 | */ |
| 65 | int __must_check media_device_register(struct media_device *mdev) |
| 66 | { |
| 67 | int ret; |
| 68 | |
| 69 | if (WARN_ON(mdev->dev == NULL || mdev->model[0] == 0)) |
| 70 | return -EINVAL; |
| 71 | |
| 72 | /* Register the device node. */ |
| 73 | mdev->devnode.fops = &media_device_fops; |
| 74 | mdev->devnode.parent = mdev->dev; |
| 75 | mdev->devnode.release = media_device_release; |
| 76 | ret = media_devnode_register(&mdev->devnode); |
| 77 | if (ret < 0) |
| 78 | return ret; |
| 79 | |
| 80 | ret = device_create_file(&mdev->devnode.dev, &dev_attr_model); |
| 81 | if (ret < 0) { |
| 82 | media_devnode_unregister(&mdev->devnode); |
| 83 | return ret; |
| 84 | } |
| 85 | |
| 86 | return 0; |
| 87 | } |
| 88 | EXPORT_SYMBOL_GPL(media_device_register); |
| 89 | |
| 90 | /** |
| 91 | * media_device_unregister - unregister a media device |
| 92 | * @mdev: The media device |
| 93 | * |
| 94 | */ |
| 95 | void media_device_unregister(struct media_device *mdev) |
| 96 | { |
| 97 | device_remove_file(&mdev->devnode.dev, &dev_attr_model); |
| 98 | media_devnode_unregister(&mdev->devnode); |
| 99 | } |
| 100 | EXPORT_SYMBOL_GPL(media_device_unregister); |