diff options
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/video/v4l2-dev.c | 38 |
1 files changed, 20 insertions, 18 deletions
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c index 1219721894a..4e61c77b763 100644 --- a/drivers/media/video/v4l2-dev.c +++ b/drivers/media/video/v4l2-dev.c @@ -66,7 +66,7 @@ static struct device_attribute video_device_attrs[] = { */ 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); +static DECLARE_BITMAP(devnode_nums[VFL_TYPE_MAX], VIDEO_NUM_DEVICES); struct video_device *video_device_alloc(void) { @@ -119,8 +119,8 @@ static void v4l2_device_release(struct device *cd) the release() callback. */ vdev->cdev = NULL; - /* Mark minor as free */ - clear_bit(vdev->num, video_nums[vdev->vfl_type]); + /* Mark device node number as free */ + clear_bit(vdev->num, devnode_nums[vdev->vfl_type]); mutex_unlock(&videodev_lock); @@ -338,13 +338,14 @@ static int get_index(struct video_device *vdev) * 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) * - * 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. * @@ -401,7 +402,7 @@ int video_register_device(struct video_device *vdev, int type, int nr) if (vdev->v4l2_dev && vdev->v4l2_dev->dev) vdev->parent = vdev->v4l2_dev->dev; - /* Part 2: find a free minor, kernel number and device index. */ + /* 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. @@ -432,21 +433,22 @@ int video_register_device(struct video_device *vdev, int type, int nr) } #endif - /* Pick a minor number */ + /* Pick a device node number */ mutex_lock(&videodev_lock); - nr = find_next_zero_bit(video_nums[type], minor_cnt, nr == -1 ? 0 : nr); + nr = find_next_zero_bit(devnode_nums[type], minor_cnt, nr == -1 ? 0 : nr); if (nr == minor_cnt) - nr = find_first_zero_bit(video_nums[type], minor_cnt); + nr = find_first_zero_bit(devnode_nums[type], minor_cnt); if (nr == minor_cnt) { - printk(KERN_ERR "could not get a free kernel number\n"); + 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 kernel number to minor number */ + /* 1-on-1 mapping of device node number to minor number */ i = nr; #else - /* The kernel number and minor numbers are independent */ + /* 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; @@ -458,7 +460,7 @@ int video_register_device(struct video_device *vdev, int type, int nr) #endif vdev->minor = i + minor_offset; vdev->num = nr; - set_bit(nr, video_nums[type]); + set_bit(nr, devnode_nums[type]); /* Should not happen since we thought this minor was free */ WARN_ON(video_device[vdev->minor] != NULL); vdev->index = get_index(vdev); @@ -492,7 +494,7 @@ int video_register_device(struct video_device *vdev, int type, int nr) 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, nr); + 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__); @@ -512,7 +514,7 @@ cleanup: mutex_lock(&videodev_lock); if (vdev->cdev) cdev_del(vdev->cdev); - clear_bit(vdev->num, video_nums[type]); + clear_bit(vdev->num, devnode_nums[type]); mutex_unlock(&videodev_lock); /* Mark this video device as never having been registered. */ vdev->minor = -1; |