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Diffstat (limited to 'include/media/media-devnode.h')
| -rw-r--r-- | include/media/media-devnode.h | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/include/media/media-devnode.h b/include/media/media-devnode.h new file mode 100644 index 00000000000..f6caafc874c --- /dev/null +++ b/include/media/media-devnode.h @@ -0,0 +1,97 @@ +/* + * Media device node + * + * Copyright (C) 2010 Nokia Corporation + * + * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.com> + * Sakari Ailus <sakari.ailus@iki.fi> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * -- + * + * Common functions for media-related drivers to register and unregister media + * device nodes. + */ + +#ifndef _MEDIA_DEVNODE_H +#define _MEDIA_DEVNODE_H + +#include <linux/poll.h> +#include <linux/fs.h> +#include <linux/device.h> +#include <linux/cdev.h> + +/* + * Flag to mark the media_devnode struct as registered. Drivers must not touch + * this flag directly, it will be set and cleared by media_devnode_register and + * media_devnode_unregister. + */ +#define MEDIA_FLAG_REGISTERED 0 + +struct media_file_operations { + struct module *owner; + ssize_t (*read) (struct file *, char __user *, size_t, loff_t *); + ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *); + unsigned int (*poll) (struct file *, struct poll_table_struct *); + long (*ioctl) (struct file *, unsigned int, unsigned long); + int (*open) (struct file *); + int (*release) (struct file *); +}; + +/** + * struct media_devnode - Media device node + * @parent: parent device + * @minor: device node minor number + * @flags: flags, combination of the MEDIA_FLAG_* constants + * + * This structure represents a media-related device node. + * + * The @parent is a physical device. It must be set by core or device drivers + * before registering the node. + */ +struct media_devnode { + /* device ops */ + const struct media_file_operations *fops; + + /* sysfs */ + struct device dev; /* media device */ + struct cdev cdev; /* character device */ + struct device *parent; /* device parent */ + + /* device info */ + int minor; + unsigned long flags; /* Use bitops to access flags */ + + /* callbacks */ + void (*release)(struct media_devnode *mdev); +}; + +/* dev to media_devnode */ +#define to_media_devnode(cd) container_of(cd, struct media_devnode, dev) + +int __must_check media_devnode_register(struct media_devnode *mdev); +void media_devnode_unregister(struct media_devnode *mdev); + +static inline struct media_devnode *media_devnode_data(struct file *filp) +{ + return filp->private_data; +} + +static inline int media_devnode_is_registered(struct media_devnode *mdev) +{ + return test_bit(MEDIA_FLAG_REGISTERED, &mdev->flags); +} + +#endif /* _MEDIA_DEVNODE_H */ |