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Diffstat (limited to 'drivers/media/video/v4l2-dev.c')
-rw-r--r--drivers/media/video/v4l2-dev.c427
1 files changed, 0 insertions, 427 deletions
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
deleted file mode 100644
index ccd6566a515..00000000000
--- a/drivers/media/video/v4l2-dev.c
+++ /dev/null
@@ -1,427 +0,0 @@
-/*
- * Video capture interface for Linux version 2
- *
- * A generic video device interface for the LINUX operating system
- * using a set of device structures/vectors for low level operations.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- *
- * Authors: Alan Cox, <alan@redhat.com> (version 1)
- * Mauro Carvalho Chehab <mchehab@infradead.org> (version 2)
- *
- * Fixes: 20000516 Claudio Matsuoka <claudio@conectiva.com>
- * - Added procfs support
- */
-
-#include <linux/module.h>
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/string.h>
-#include <linux/errno.h>
-#include <linux/init.h>
-#include <linux/kmod.h>
-#include <linux/slab.h>
-#include <linux/smp_lock.h>
-#include <asm/uaccess.h>
-#include <asm/system.h>
-
-#include <media/v4l2-common.h>
-
-#define VIDEO_NUM_DEVICES 256
-#define VIDEO_NAME "video4linux"
-
-/*
- * sysfs stuff
- */
-
-static ssize_t show_index(struct device *cd,
- struct device_attribute *attr, char *buf)
-{
- struct video_device *vfd = container_of(cd, struct video_device, dev);
-
- return sprintf(buf, "%i\n", vfd->index);
-}
-
-static ssize_t show_name(struct device *cd,
- struct device_attribute *attr, char *buf)
-{
- struct video_device *vfd = container_of(cd, struct video_device, dev);
-
- return sprintf(buf, "%.*s\n", (int)sizeof(vfd->name), vfd->name);
-}
-
-static struct device_attribute video_device_attrs[] = {
- __ATTR(name, S_IRUGO, show_name, NULL),
- __ATTR(index, S_IRUGO, show_index, NULL),
- __ATTR_NULL
-};
-
-/*
- * Active devices
- */
-static struct video_device *video_device[VIDEO_NUM_DEVICES];
-static DEFINE_MUTEX(videodev_lock);
-static DECLARE_BITMAP(video_nums[VFL_TYPE_MAX], VIDEO_NUM_DEVICES);
-
-struct video_device *video_device_alloc(void)
-{
- return kzalloc(sizeof(struct video_device), GFP_KERNEL);
-}
-EXPORT_SYMBOL(video_device_alloc);
-
-void video_device_release(struct video_device *vfd)
-{
- kfree(vfd);
-}
-EXPORT_SYMBOL(video_device_release);
-
-void video_device_release_empty(struct video_device *vfd)
-{
- /* Do nothing */
- /* Only valid when the video_device struct is a static. */
-}
-EXPORT_SYMBOL(video_device_release_empty);
-
-/* Called when the last user of the character device is gone. */
-static void v4l2_chardev_release(struct kobject *kobj)
-{
- struct video_device *vfd = container_of(kobj, struct video_device, cdev.kobj);
-
- mutex_lock(&videodev_lock);
- if (video_device[vfd->minor] != vfd) {
- mutex_unlock(&videodev_lock);
- BUG();
- return;
- }
-
- /* Free up this device for reuse */
- video_device[vfd->minor] = NULL;
- clear_bit(vfd->num, video_nums[vfd->vfl_type]);
- mutex_unlock(&videodev_lock);
-
- /* Release the character device */
- vfd->cdev_release(kobj);
- /* Release video_device and perform other
- cleanups as needed. */
- if (vfd->release)
- vfd->release(vfd);
-}
-
-/* The new kobj_type for the character device */
-static struct kobj_type v4l2_ktype_cdev_default = {
- .release = v4l2_chardev_release,
-};
-
-static void video_release(struct device *cd)
-{
- struct video_device *vfd = container_of(cd, struct video_device, dev);
-
- /* It's now safe to delete the char device.
- This will either trigger the v4l2_chardev_release immediately (if
- the refcount goes to 0) or later when the last user of the
- character device closes it. */
- cdev_del(&vfd->cdev);
-}
-
-static struct class video_class = {
- .name = VIDEO_NAME,
- .dev_attrs = video_device_attrs,
- .dev_release = video_release,
-};
-
-struct video_device *video_devdata(struct file *file)
-{
- return video_device[iminor(file->f_path.dentry->d_inode)];
-}
-EXPORT_SYMBOL(video_devdata);
-
-/**
- * get_index - assign stream number based on parent device
- * @vdev: video_device to assign index number to, vdev->dev should be assigned
- * @num: -1 if auto assign, requested number otherwise
- *
- *
- * returns -ENFILE if num is already in use, a free index number if
- * successful.
- */
-static int get_index(struct video_device *vdev, int num)
-{
- u32 used = 0;
- const int max_index = sizeof(used) * 8 - 1;
- int i;
-
- /* Currently a single v4l driver instance cannot create more than
- 32 devices.
- Increase to u64 or an array of u32 if more are needed. */
- if (num > max_index) {
- printk(KERN_ERR "videodev: %s num is too large\n", __func__);
- return -EINVAL;
- }
-
- for (i = 0; i < VIDEO_NUM_DEVICES; i++) {
- if (video_device[i] != NULL &&
- video_device[i] != vdev &&
- video_device[i]->parent == vdev->parent) {
- used |= 1 << video_device[i]->index;
- }
- }
-
- if (num >= 0) {
- if (used & (1 << num))
- return -ENFILE;
- return num;
- }
-
- i = ffz(used);
- return i > max_index ? -ENFILE : i;
-}
-
-static const struct file_operations video_fops;
-
-int video_register_device(struct video_device *vfd, int type, int nr)
-{
- return video_register_device_index(vfd, type, nr, -1);
-}
-EXPORT_SYMBOL(video_register_device);
-
-/**
- * video_register_device_index - register video4linux devices
- * @vfd: video device structure we want to register
- * @type: type of device to register
- * @nr: which device number (0 == /dev/video0, 1 == /dev/video1, ...
- * -1 == first free)
- * @index: stream number based on parent device;
- * -1 if auto assign, requested number otherwise
- *
- * The registration code assigns minor numbers based on the type
- * requested. -ENFILE is returned in all the device slots for this
- * category are full. If not then the minor field is set and the
- * driver initialize function is called (if non %NULL).
- *
- * Zero is returned on success.
- *
- * Valid types are
- *
- * %VFL_TYPE_GRABBER - A frame grabber
- *
- * %VFL_TYPE_VTX - A teletext device
- *
- * %VFL_TYPE_VBI - Vertical blank data (undecoded)
- *
- * %VFL_TYPE_RADIO - A radio card
- */
-
-int video_register_device_index(struct video_device *vfd, int type, int nr,
- int index)
-{
- int i = 0;
- int ret;
- int minor_offset = 0;
- int minor_cnt = VIDEO_NUM_DEVICES;
- const char *name_base;
- void *priv = video_get_drvdata(vfd);
-
- /* the release callback MUST be present */
- BUG_ON(!vfd->release);
-
- if (vfd == NULL)
- return -EINVAL;
-
- switch (type) {
- case VFL_TYPE_GRABBER:
- name_base = "video";
- break;
- case VFL_TYPE_VTX:
- name_base = "vtx";
- break;
- case VFL_TYPE_VBI:
- name_base = "vbi";
- break;
- case VFL_TYPE_RADIO:
- name_base = "radio";
- break;
- default:
- printk(KERN_ERR "%s called with unknown type: %d\n",
- __func__, type);
- return -EINVAL;
- }
-
- vfd->vfl_type = type;
-
-#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
- /* Keep the ranges for the first four types for historical
- * reasons.
- * Newer devices (not yet in place) should use the range
- * of 128-191 and just pick the first free minor there
- * (new style). */
- switch (type) {
- case VFL_TYPE_GRABBER:
- minor_offset = 0;
- minor_cnt = 64;
- break;
- case VFL_TYPE_RADIO:
- minor_offset = 64;
- minor_cnt = 64;
- break;
- case VFL_TYPE_VTX:
- minor_offset = 192;
- minor_cnt = 32;
- break;
- case VFL_TYPE_VBI:
- minor_offset = 224;
- minor_cnt = 32;
- break;
- default:
- minor_offset = 128;
- minor_cnt = 64;
- break;
- }
-#endif
-
- /* Initialize the character device */
- cdev_init(&vfd->cdev, vfd->fops);
- vfd->cdev.owner = vfd->fops->owner;
- /* pick a minor number */
- mutex_lock(&videodev_lock);
- nr = find_next_zero_bit(video_nums[type], minor_cnt, nr == -1 ? 0 : nr);
- if (nr == minor_cnt)
- nr = find_first_zero_bit(video_nums[type], minor_cnt);
- if (nr == minor_cnt) {
- printk(KERN_ERR "could not get a free kernel number\n");
- mutex_unlock(&videodev_lock);
- return -ENFILE;
- }
-#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
- /* 1-on-1 mapping of kernel number to minor number */
- i = nr;
-#else
- /* The kernel number and minor numbers are independent */
- for (i = 0; i < VIDEO_NUM_DEVICES; i++)
- if (video_device[i] == NULL)
- break;
- if (i == VIDEO_NUM_DEVICES) {
- mutex_unlock(&videodev_lock);
- printk(KERN_ERR "could not get a free minor\n");
- return -ENFILE;
- }
-#endif
- vfd->minor = i + minor_offset;
- vfd->num = nr;
- set_bit(nr, video_nums[type]);
- BUG_ON(video_device[vfd->minor]);
- video_device[vfd->minor] = vfd;
-
- ret = get_index(vfd, index);
- vfd->index = ret;
-
- mutex_unlock(&videodev_lock);
-
- if (ret < 0) {
- printk(KERN_ERR "%s: get_index failed\n", __func__);
- goto fail_minor;
- }
-
- ret = cdev_add(&vfd->cdev, MKDEV(VIDEO_MAJOR, vfd->minor), 1);
- if (ret < 0) {
- printk(KERN_ERR "%s: cdev_add failed\n", __func__);
- goto fail_minor;
- }
- /* sysfs class */
- memset(&vfd->dev, 0, sizeof(vfd->dev));
- /* The memset above cleared the device's drvdata, so
- put back the copy we made earlier. */
- video_set_drvdata(vfd, priv);
- vfd->dev.class = &video_class;
- vfd->dev.devt = MKDEV(VIDEO_MAJOR, vfd->minor);
- if (vfd->parent)
- vfd->dev.parent = vfd->parent;
- sprintf(vfd->dev.bus_id, "%s%d", name_base, nr);
- ret = device_register(&vfd->dev);
- if (ret < 0) {
- printk(KERN_ERR "%s: device_register failed\n", __func__);
- goto del_cdev;
- }
- /* Remember the cdev's release function */
- vfd->cdev_release = vfd->cdev.kobj.ktype->release;
- /* Install our own */
- vfd->cdev.kobj.ktype = &v4l2_ktype_cdev_default;
- return 0;
-
-del_cdev:
- cdev_del(&vfd->cdev);
-
-fail_minor:
- mutex_lock(&videodev_lock);
- video_device[vfd->minor] = NULL;
- clear_bit(vfd->num, video_nums[type]);
- mutex_unlock(&videodev_lock);
- vfd->minor = -1;
- return ret;
-}
-EXPORT_SYMBOL(video_register_device_index);
-
-/**
- * video_unregister_device - unregister a video4linux device
- * @vfd: the device to unregister
- *
- * This unregisters the passed device and deassigns the minor
- * number. Future open calls will be met with errors.
- */
-
-void video_unregister_device(struct video_device *vfd)
-{
- device_unregister(&vfd->dev);
-}
-EXPORT_SYMBOL(video_unregister_device);
-
-/*
- * Initialise video for linux
- */
-static int __init videodev_init(void)
-{
- dev_t dev = MKDEV(VIDEO_MAJOR, 0);
- int ret;
-
- printk(KERN_INFO "Linux video capture interface: v2.00\n");
- ret = register_chrdev_region(dev, VIDEO_NUM_DEVICES, VIDEO_NAME);
- if (ret < 0) {
- printk(KERN_WARNING "videodev: unable to get major %d\n",
- VIDEO_MAJOR);
- return ret;
- }
-
- ret = class_register(&video_class);
- if (ret < 0) {
- unregister_chrdev_region(dev, VIDEO_NUM_DEVICES);
- printk(KERN_WARNING "video_dev: class_register failed\n");
- return -EIO;
- }
-
- return 0;
-}
-
-static void __exit videodev_exit(void)
-{
- dev_t dev = MKDEV(VIDEO_MAJOR, 0);
-
- class_unregister(&video_class);
- unregister_chrdev_region(dev, VIDEO_NUM_DEVICES);
-}
-
-module_init(videodev_init)
-module_exit(videodev_exit)
-
-MODULE_AUTHOR("Alan Cox, Mauro Carvalho Chehab <mchehab@infradead.org>");
-MODULE_DESCRIPTION("Device registrar for Video4Linux drivers v2");
-MODULE_LICENSE("GPL");
-
-
-/*
- * Local variables:
- * c-basic-offset: 8
- * End:
- */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-13 17:25:45 +0000