| Laurent Pinchart | cf4b921 | 2009-12-09 08:39:56 -0300 | [diff] [blame] | 1 | /* |
| 2 | * Media device node |
| 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 | * |
| 24 | * Common functions for media-related drivers to register and unregister media |
| 25 | * device nodes. |
| 26 | */ |
| 27 | |
| 28 | #ifndef _MEDIA_DEVNODE_H |
| 29 | #define _MEDIA_DEVNODE_H |
| 30 | |
| 31 | #include <linux/poll.h> |
| 32 | #include <linux/fs.h> |
| 33 | #include <linux/device.h> |
| 34 | #include <linux/cdev.h> |
| 35 | |
| 36 | /* |
| 37 | * Flag to mark the media_devnode struct as registered. Drivers must not touch |
| 38 | * this flag directly, it will be set and cleared by media_devnode_register and |
| 39 | * media_devnode_unregister. |
| 40 | */ |
| 41 | #define MEDIA_FLAG_REGISTERED 0 |
| 42 | |
| 43 | struct media_file_operations { |
| 44 | struct module *owner; |
| 45 | ssize_t (*read) (struct file *, char __user *, size_t, loff_t *); |
| 46 | ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *); |
| 47 | unsigned int (*poll) (struct file *, struct poll_table_struct *); |
| 48 | long (*ioctl) (struct file *, unsigned int, unsigned long); |
| 49 | int (*open) (struct file *); |
| 50 | int (*release) (struct file *); |
| 51 | }; |
| 52 | |
| 53 | /** |
| 54 | * struct media_devnode - Media device node |
| 55 | * @parent: parent device |
| 56 | * @minor: device node minor number |
| 57 | * @flags: flags, combination of the MEDIA_FLAG_* constants |
| 58 | * |
| 59 | * This structure represents a media-related device node. |
| 60 | * |
| 61 | * The @parent is a physical device. It must be set by core or device drivers |
| 62 | * before registering the node. |
| 63 | */ |
| 64 | struct media_devnode { |
| 65 | /* device ops */ |
| 66 | const struct media_file_operations *fops; |
| 67 | |
| 68 | /* sysfs */ |
| 69 | struct device dev; /* media device */ |
| 70 | struct cdev cdev; /* character device */ |
| 71 | struct device *parent; /* device parent */ |
| 72 | |
| 73 | /* device info */ |
| 74 | int minor; |
| 75 | unsigned long flags; /* Use bitops to access flags */ |
| 76 | |
| 77 | /* callbacks */ |
| 78 | void (*release)(struct media_devnode *mdev); |
| 79 | }; |
| 80 | |
| 81 | /* dev to media_devnode */ |
| 82 | #define to_media_devnode(cd) container_of(cd, struct media_devnode, dev) |
| 83 | |
| 84 | int __must_check media_devnode_register(struct media_devnode *mdev); |
| 85 | void media_devnode_unregister(struct media_devnode *mdev); |
| 86 | |
| 87 | static inline struct media_devnode *media_devnode_data(struct file *filp) |
| 88 | { |
| 89 | return filp->private_data; |
| 90 | } |
| 91 | |
| 92 | static inline int media_devnode_is_registered(struct media_devnode *mdev) |
| 93 | { |
| 94 | return test_bit(MEDIA_FLAG_REGISTERED, &mdev->flags); |
| 95 | } |
| 96 | |
| 97 | #endif /* _MEDIA_DEVNODE_H */ |