V4L/DVB (12725): v4l: warn when desired devnodenr is in use & add _no_warn function
Warn when the desired device node number is already in use, except when
the new video_register_device_no_warn function is called since in some
use-cases that warning is not relevant.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
index 4715f08..500cbe9 100644
--- a/drivers/media/video/v4l2-dev.c
+++ b/drivers/media/video/v4l2-dev.c
@@ -382,6 +382,8 @@
* @type: type of device to register
* @nr: which device node number (0 == /dev/video0, 1 == /dev/video1, ...
* -1 == first free)
+ * @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 and device node numbers
* based on the requested type and registers the new device node with
@@ -401,7 +403,8 @@
*
* %VFL_TYPE_RADIO - A radio card
*/
-int video_register_device(struct video_device *vdev, int type, int nr)
+static int __video_register_device(struct video_device *vdev, int type, int nr,
+ int warn_if_nr_in_use)
{
int i = 0;
int ret;
@@ -547,6 +550,10 @@
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%d\n",
+ __func__, name_base, nr, name_base, vdev->num);
+
/* Part 5: Activate this minor. The char device can now be used. */
mutex_lock(&videodev_lock);
video_device[vdev->minor] = vdev;
@@ -563,8 +570,19 @@
vdev->minor = -1;
return ret;
}
+
+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
* @vdev: the device to unregister