* 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)
+ * Authors: Alan Cox, <alan@lxorguk.ukuu.org.uk> (version 1)
* Mauro Carvalho Chehab <mchehab@infradead.org> (version 2)
*
* Fixes: 20000516 Claudio Matsuoka <claudio@conectiva.com>
#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>
+#include <media/v4l2-device.h>
+#include <media/v4l2-ioctl.h>
#define VIDEO_NUM_DEVICES 256
#define VIDEO_NAME "video4linux"
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);
+ struct video_device *vdev = to_video_device(cd);
- return sprintf(buf, "%i\n", vfd->index);
+ return sprintf(buf, "%i\n", vdev->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);
+ struct video_device *vdev = to_video_device(cd);
- return sprintf(buf, "%.*s\n", (int)sizeof(vfd->name), vfd->name);
+ return sprintf(buf, "%.*s\n", (int)sizeof(vdev->name), vdev->name);
}
static struct device_attribute video_device_attrs[] = {
__ATTR_NULL
};
+/*
+ * Active devices
+ */
+static struct video_device *video_device[VIDEO_NUM_DEVICES];
+static DEFINE_MUTEX(videodev_lock);
+static DECLARE_BITMAP(devnode_nums[VFL_TYPE_MAX], VIDEO_NUM_DEVICES);
+
+/* Device node utility functions */
+
+/* Note: these utility functions all assume that vfl_type is in the range
+ [0, VFL_TYPE_MAX-1]. */
+
+#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
+/* Return the bitmap corresponding to vfl_type. */
+static inline unsigned long *devnode_bits(int vfl_type)
+{
+ /* Any types not assigned to fixed minor ranges must be mapped to
+ one single bitmap for the purposes of finding a free node number
+ since all those unassigned types use the same minor range. */
+ int idx = (vfl_type > VFL_TYPE_VTX) ? VFL_TYPE_MAX - 1 : vfl_type;
+
+ return devnode_nums[idx];
+}
+#else
+/* Return the bitmap corresponding to vfl_type. */
+static inline unsigned long *devnode_bits(int vfl_type)
+{
+ return devnode_nums[vfl_type];
+}
+#endif
+
+/* Mark device node number vdev->num as used */
+static inline void devnode_set(struct video_device *vdev)
+{
+ set_bit(vdev->num, devnode_bits(vdev->vfl_type));
+}
+
+/* Mark device node number vdev->num as unused */
+static inline void devnode_clear(struct video_device *vdev)
+{
+ clear_bit(vdev->num, devnode_bits(vdev->vfl_type));
+}
+
+/* Try to find a free device node number in the range [from, to> */
+static inline int devnode_find(struct video_device *vdev, int from, int to)
+{
+ return find_next_zero_bit(devnode_bits(vdev->vfl_type), to, from);
+}
+
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)
+void video_device_release(struct video_device *vdev)
{
- kfree(vfd);
+ kfree(vdev);
}
EXPORT_SYMBOL(video_device_release);
-void video_device_release_empty(struct video_device *vfd)
+void video_device_release_empty(struct video_device *vdev)
{
/* Do nothing */
/* Only valid when the video_device struct is a static. */
}
EXPORT_SYMBOL(video_device_release_empty);
-static void video_release(struct device *cd)
+static inline void video_get(struct video_device *vdev)
+{
+ get_device(&vdev->dev);
+}
+
+static inline void video_put(struct video_device *vdev)
+{
+ put_device(&vdev->dev);
+}
+
+/* Called when the last user of the video device exits. */
+static void v4l2_device_release(struct device *cd)
{
- struct video_device *vfd = container_of(cd, struct video_device, dev);
+ struct video_device *vdev = to_video_device(cd);
+
+ mutex_lock(&videodev_lock);
+ if (video_device[vdev->minor] != vdev) {
+ mutex_unlock(&videodev_lock);
+ /* should not happen */
+ WARN_ON(1);
+ return;
+ }
+
+ /* Free up this device for reuse */
+ video_device[vdev->minor] = NULL;
+
+ /* Delete the cdev on this minor as well */
+ cdev_del(vdev->cdev);
+ /* Just in case some driver tries to access this from
+ the release() callback. */
+ vdev->cdev = NULL;
+
+ /* Mark device node number as free */
+ devnode_clear(vdev);
+
+ mutex_unlock(&videodev_lock);
- vfd->release(vfd);
+ /* Release video_device and perform other
+ cleanups as needed. */
+ vdev->release(vdev);
}
static struct class video_class = {
.name = VIDEO_NAME,
.dev_attrs = video_device_attrs,
- .dev_release = video_release,
};
-/*
- * Active devices
- */
-
-static struct video_device *video_device[VIDEO_NUM_DEVICES];
-static DEFINE_MUTEX(videodev_lock);
-
struct video_device *video_devdata(struct file *file)
{
return video_device[iminor(file->f_path.dentry->d_inode)];
}
EXPORT_SYMBOL(video_devdata);
-/*
- * Open a video device - FIXME: Obsoleted
- */
-static int video_open(struct inode *inode, struct file *file)
+static ssize_t v4l2_read(struct file *filp, char __user *buf,
+ size_t sz, loff_t *off)
+{
+ struct video_device *vdev = video_devdata(filp);
+
+ if (!vdev->fops->read)
+ return -EINVAL;
+ if (!video_is_registered(vdev))
+ return -EIO;
+ return vdev->fops->read(filp, buf, sz, off);
+}
+
+static ssize_t v4l2_write(struct file *filp, const char __user *buf,
+ size_t sz, loff_t *off)
+{
+ struct video_device *vdev = video_devdata(filp);
+
+ if (!vdev->fops->write)
+ return -EINVAL;
+ if (!video_is_registered(vdev))
+ return -EIO;
+ return vdev->fops->write(filp, buf, sz, off);
+}
+
+static unsigned int v4l2_poll(struct file *filp, struct poll_table_struct *poll)
+{
+ struct video_device *vdev = video_devdata(filp);
+
+ if (!vdev->fops->poll || !video_is_registered(vdev))
+ return DEFAULT_POLLMASK;
+ return vdev->fops->poll(filp, poll);
+}
+
+static int v4l2_ioctl(struct inode *inode, struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct video_device *vdev = video_devdata(filp);
+
+ if (!vdev->fops->ioctl)
+ return -ENOTTY;
+ /* Allow ioctl to continue even if the device was unregistered.
+ Things like dequeueing buffers might still be useful. */
+ return vdev->fops->ioctl(filp, cmd, arg);
+}
+
+static long v4l2_unlocked_ioctl(struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct video_device *vdev = video_devdata(filp);
+
+ if (!vdev->fops->unlocked_ioctl)
+ return -ENOTTY;
+ /* Allow ioctl to continue even if the device was unregistered.
+ Things like dequeueing buffers might still be useful. */
+ return vdev->fops->unlocked_ioctl(filp, cmd, arg);
+}
+
+#ifdef CONFIG_MMU
+#define v4l2_get_unmapped_area NULL
+#else
+static unsigned long v4l2_get_unmapped_area(struct file *filp,
+ unsigned long addr, unsigned long len, unsigned long pgoff,
+ unsigned long flags)
+{
+ struct video_device *vdev = video_devdata(filp);
+
+ if (!vdev->fops->get_unmapped_area)
+ return -ENOSYS;
+ if (!video_is_registered(vdev))
+ return -ENODEV;
+ return vdev->fops->get_unmapped_area(filp, addr, len, pgoff, flags);
+}
+#endif
+
+static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm)
{
- unsigned int minor = iminor(inode);
- int err = 0;
- struct video_device *vfl;
- const struct file_operations *old_fops;
+ struct video_device *vdev = video_devdata(filp);
- if (minor >= VIDEO_NUM_DEVICES)
+ if (!vdev->fops->mmap || !video_is_registered(vdev))
return -ENODEV;
+ return vdev->fops->mmap(filp, vm);
+}
+
+/* Override for the open function */
+static int v4l2_open(struct inode *inode, struct file *filp)
+{
+ struct video_device *vdev;
+ int ret = 0;
+
+ /* Check if the video device is available */
mutex_lock(&videodev_lock);
- vfl = video_device[minor];
- if (vfl == NULL) {
+ vdev = video_devdata(filp);
+ /* return ENODEV if the video device has been removed
+ already or if it is not registered anymore. */
+ if (vdev == NULL || !video_is_registered(vdev)) {
mutex_unlock(&videodev_lock);
- request_module("char-major-%d-%d", VIDEO_MAJOR, minor);
- mutex_lock(&videodev_lock);
- vfl = video_device[minor];
- if (vfl == NULL) {
- mutex_unlock(&videodev_lock);
- return -ENODEV;
- }
- }
- old_fops = file->f_op;
- file->f_op = fops_get(vfl->fops);
- if (file->f_op->open)
- err = file->f_op->open(inode, file);
- if (err) {
- fops_put(file->f_op);
- file->f_op = fops_get(old_fops);
+ return -ENODEV;
}
- fops_put(old_fops);
+ /* and increase the device refcount */
+ video_get(vdev);
mutex_unlock(&videodev_lock);
- return err;
+ if (vdev->fops->open)
+ ret = vdev->fops->open(filp);
+
+ /* decrease the refcount in case of an error */
+ if (ret)
+ video_put(vdev);
+ return ret;
}
+/* Override for the release function */
+static int v4l2_release(struct inode *inode, struct file *filp)
+{
+ struct video_device *vdev = video_devdata(filp);
+ int ret = 0;
+
+ if (vdev->fops->release)
+ vdev->fops->release(filp);
+
+ /* decrease the refcount unconditionally since the release()
+ return value is ignored. */
+ video_put(vdev);
+ return ret;
+}
+
+static const struct file_operations v4l2_unlocked_fops = {
+ .owner = THIS_MODULE,
+ .read = v4l2_read,
+ .write = v4l2_write,
+ .open = v4l2_open,
+ .get_unmapped_area = v4l2_get_unmapped_area,
+ .mmap = v4l2_mmap,
+ .unlocked_ioctl = v4l2_unlocked_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = v4l2_compat_ioctl32,
+#endif
+ .release = v4l2_release,
+ .poll = v4l2_poll,
+ .llseek = no_llseek,
+};
+
+static const struct file_operations v4l2_fops = {
+ .owner = THIS_MODULE,
+ .read = v4l2_read,
+ .write = v4l2_write,
+ .open = v4l2_open,
+ .get_unmapped_area = v4l2_get_unmapped_area,
+ .mmap = v4l2_mmap,
+ .ioctl = v4l2_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = v4l2_compat_ioctl32,
+#endif
+ .release = v4l2_release,
+ .poll = v4l2_poll,
+ .llseek = no_llseek,
+};
+
/**
- * 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
+ * get_index - assign stream index number based on parent device
+ * @vdev: video_device to assign index number to, vdev->parent should be assigned
*
+ * Note that when this is called the new device has not yet been registered
+ * in the video_device array, but it was able to obtain a minor number.
*
- * returns -ENFILE if num is already in use, a free index number if
- * successful.
+ * This means that we can always obtain a free stream index number since
+ * the worst case scenario is that there are VIDEO_NUM_DEVICES - 1 slots in
+ * use of the video_device array.
+ *
+ * Returns a free index number.
*/
-static int get_index(struct video_device *vdev, int num)
+static int get_index(struct video_device *vdev)
{
- u32 used = 0;
- const int max_index = sizeof(used) * 8 - 1;
+ /* This can be static since this function is called with the global
+ videodev_lock held. */
+ static DECLARE_BITMAP(used, VIDEO_NUM_DEVICES);
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;
- }
+ /* Some drivers do not set the parent. In that case always return 0. */
+ if (vdev->parent == NULL)
+ return 0;
+
+ bitmap_zero(used, VIDEO_NUM_DEVICES);
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;
+ set_bit(video_device[i]->index, used);
}
}
- if (num >= 0) {
- if (used & (1 << num))
- return -ENFILE;
- return num;
- }
-
- i = ffz(used);
- return i > max_index ? -ENFILE : i;
+ return find_first_zero_bit(used, VIDEO_NUM_DEVICES);
}
-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
+ * video_register_device - register video4linux devices
+ * @vdev: video device structure we want to register
* @type: type of device to register
- * @nr: which device number (0 == /dev/video0, 1 == /dev/video1, ...
+ * @nr: which device node number (0 == /dev/video0, 1 == /dev/video1, ...
* -1 == first free)
- * @index: stream number based on parent device;
- * -1 if auto assign, requested number otherwise
+ * @warn_if_nr_in_use: warn if the desired device node number
+ * was already in use and another number was chosen instead.
*
- * 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).
+ * The registration code assigns minor numbers and device node numbers
+ * based on the requested type and registers the new device node with
+ * the kernel.
+ * An error is returned if no free minor or device node number could be
+ * found, or if the registration of the device node failed.
*
* Zero is returned on success.
*
*
* %VFL_TYPE_RADIO - A radio card
*/
-
-int video_register_device_index(struct video_device *vfd, int type, int nr,
- int index)
+static int __video_register_device(struct video_device *vdev, int type, int nr,
+ int warn_if_nr_in_use)
{
int i = 0;
- int base;
- int end;
int ret;
- char *name_base;
- void *priv = video_get_drvdata(vfd);
+ int minor_offset = 0;
+ int minor_cnt = VIDEO_NUM_DEVICES;
+ const char *name_base;
+ void *priv = video_get_drvdata(vdev);
- /* the release callback MUST be present */
- BUG_ON(!vfd->release);
+ /* A minor value of -1 marks this video device as never
+ having been registered */
+ vdev->minor = -1;
- if (vfd == NULL)
+ /* the release callback MUST be present */
+ WARN_ON(!vdev->release);
+ if (!vdev->release)
return -EINVAL;
+ /* v4l2_fh support */
+ spin_lock_init(&vdev->fh_lock);
+ INIT_LIST_HEAD(&vdev->fh_list);
+
+ /* Part 1: check device type */
switch (type) {
case VFL_TYPE_GRABBER:
- base = MINOR_VFL_TYPE_GRABBER_MIN;
- end = MINOR_VFL_TYPE_GRABBER_MAX+1;
name_base = "video";
break;
case VFL_TYPE_VTX:
- base = MINOR_VFL_TYPE_VTX_MIN;
- end = MINOR_VFL_TYPE_VTX_MAX+1;
name_base = "vtx";
break;
case VFL_TYPE_VBI:
- base = MINOR_VFL_TYPE_VBI_MIN;
- end = MINOR_VFL_TYPE_VBI_MAX+1;
name_base = "vbi";
break;
case VFL_TYPE_RADIO:
- base = MINOR_VFL_TYPE_RADIO_MIN;
- end = MINOR_VFL_TYPE_RADIO_MAX+1;
name_base = "radio";
break;
default:
return -EINVAL;
}
- /* pick a minor number */
- mutex_lock(&videodev_lock);
- if (nr >= 0 && nr < end-base) {
- /* use the one the driver asked for */
- i = base + nr;
- if (NULL != video_device[i]) {
- mutex_unlock(&videodev_lock);
- return -ENFILE;
- }
- } else {
- /* use first free */
- for (i = base; i < end; i++)
- if (NULL == video_device[i])
- break;
- if (i == end) {
- mutex_unlock(&videodev_lock);
- return -ENFILE;
- }
+ vdev->vfl_type = type;
+ vdev->cdev = NULL;
+ if (vdev->v4l2_dev && vdev->v4l2_dev->dev)
+ vdev->parent = vdev->v4l2_dev->dev;
+
+ /* Part 2: find a free minor, device node number and device index. */
+#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;
}
- video_device[i] = vfd;
- vfd->vfl_type = type;
- vfd->minor = i;
-
- ret = get_index(vfd, index);
- vfd->index = ret;
+#endif
+ /* Pick a device node number */
+ mutex_lock(&videodev_lock);
+ nr = devnode_find(vdev, nr == -1 ? 0 : nr, minor_cnt);
+ if (nr == minor_cnt)
+ nr = devnode_find(vdev, 0, minor_cnt);
+ if (nr == minor_cnt) {
+ printk(KERN_ERR "could not get a free device node number\n");
+ mutex_unlock(&videodev_lock);
+ return -ENFILE;
+ }
+#ifdef CONFIG_VIDEO_FIXED_MINOR_RANGES
+ /* 1-on-1 mapping of device node number to minor number */
+ i = nr;
+#else
+ /* The device node number and minor numbers are independent, so
+ we just find the first free minor number. */
+ 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
+ vdev->minor = i + minor_offset;
+ vdev->num = nr;
+ devnode_set(vdev);
+
+ /* Should not happen since we thought this minor was free */
+ WARN_ON(video_device[vdev->minor] != NULL);
+ vdev->index = get_index(vdev);
mutex_unlock(&videodev_lock);
+ /* Part 3: Initialize the character device */
+ vdev->cdev = cdev_alloc();
+ if (vdev->cdev == NULL) {
+ ret = -ENOMEM;
+ goto cleanup;
+ }
+ if (vdev->fops->unlocked_ioctl)
+ vdev->cdev->ops = &v4l2_unlocked_fops;
+ else
+ vdev->cdev->ops = &v4l2_fops;
+ vdev->cdev->owner = vdev->fops->owner;
+ ret = cdev_add(vdev->cdev, MKDEV(VIDEO_MAJOR, vdev->minor), 1);
if (ret < 0) {
- printk(KERN_ERR "%s: get_index failed\n", __func__);
- goto fail_minor;
+ printk(KERN_ERR "%s: cdev_add failed\n", __func__);
+ kfree(vdev->cdev);
+ vdev->cdev = NULL;
+ goto cleanup;
}
- /* sysfs class */
- memset(&vfd->dev, 0, sizeof(vfd->dev));
+ /* Part 4: register the device with sysfs */
+ memset(&vdev->dev, 0, sizeof(vdev->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, i - base);
- ret = device_register(&vfd->dev);
+ video_set_drvdata(vdev, priv);
+ vdev->dev.class = &video_class;
+ vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor);
+ if (vdev->parent)
+ vdev->dev.parent = vdev->parent;
+ dev_set_name(&vdev->dev, "%s%d", name_base, vdev->num);
+ ret = device_register(&vdev->dev);
if (ret < 0) {
printk(KERN_ERR "%s: device_register failed\n", __func__);
- goto fail_minor;
+ goto cleanup;
}
+ /* Register the release callback that will be called when the last
+ reference to the device goes away. */
+ vdev->dev.release = v4l2_device_release;
+ if (nr != -1 && nr != vdev->num && warn_if_nr_in_use)
+ printk(KERN_WARNING "%s: requested %s%d, got %s\n", __func__,
+ name_base, nr, video_device_node_name(vdev));
+
+ /* Part 5: Activate this minor. The char device can now be used. */
+ set_bit(V4L2_FL_REGISTERED, &vdev->flags);
+ mutex_lock(&videodev_lock);
+ video_device[vdev->minor] = vdev;
+ mutex_unlock(&videodev_lock);
return 0;
-fail_minor:
+cleanup:
mutex_lock(&videodev_lock);
- video_device[vfd->minor] = NULL;
+ if (vdev->cdev)
+ cdev_del(vdev->cdev);
+ devnode_clear(vdev);
mutex_unlock(&videodev_lock);
- vfd->minor = -1;
+ /* Mark this video device as never having been registered. */
+ vdev->minor = -1;
return ret;
}
-EXPORT_SYMBOL(video_register_device_index);
+
+int video_register_device(struct video_device *vdev, int type, int nr)
+{
+ return __video_register_device(vdev, type, nr, 1);
+}
+EXPORT_SYMBOL(video_register_device);
+
+int video_register_device_no_warn(struct video_device *vdev, int type, int nr)
+{
+ return __video_register_device(vdev, type, nr, 0);
+}
+EXPORT_SYMBOL(video_register_device_no_warn);
/**
* video_unregister_device - unregister a video4linux device
- * @vfd: the device to unregister
+ * @vdev: the device to unregister
*
- * This unregisters the passed device and deassigns the minor
- * number. Future open calls will be met with errors.
+ * This unregisters the passed device. Future open calls will
+ * be met with errors.
*/
-
-void video_unregister_device(struct video_device *vfd)
+void video_unregister_device(struct video_device *vdev)
{
- mutex_lock(&videodev_lock);
- if (video_device[vfd->minor] != vfd)
- panic("videodev: bad unregister");
+ /* Check if vdev was ever registered at all */
+ if (!vdev || !video_is_registered(vdev))
+ return;
- video_device[vfd->minor] = NULL;
- device_unregister(&vfd->dev);
+ mutex_lock(&videodev_lock);
+ clear_bit(V4L2_FL_REGISTERED, &vdev->flags);
mutex_unlock(&videodev_lock);
+ device_unregister(&vdev->dev);
}
EXPORT_SYMBOL(video_unregister_device);
/*
- * Video fs operations
- */
-static const struct file_operations video_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .open = video_open,
-};
-
-/*
* 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");
- if (register_chrdev(VIDEO_MAJOR, VIDEO_NAME, &video_fops)) {
- printk(KERN_WARNING "video_dev: unable to get major %d\n", VIDEO_MAJOR);
- return -EIO;
+ 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(VIDEO_MAJOR, VIDEO_NAME);
+ unregister_chrdev_region(dev, VIDEO_NUM_DEVICES);
printk(KERN_WARNING "video_dev: class_register failed\n");
return -EIO;
}
static void __exit videodev_exit(void)
{
+ dev_t dev = MKDEV(VIDEO_MAJOR, 0);
+
class_unregister(&video_class);
- unregister_chrdev(VIDEO_MAJOR, VIDEO_NAME);
+ unregister_chrdev_region(dev, VIDEO_NUM_DEVICES);
}
module_init(videodev_init)
MODULE_AUTHOR("Alan Cox, Mauro Carvalho Chehab <mchehab@infradead.org>");
MODULE_DESCRIPTION("Device registrar for Video4Linux drivers v2");
MODULE_LICENSE("GPL");
+MODULE_ALIAS_CHARDEV_MAJOR(VIDEO_MAJOR);
/*
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff