V4L/DVB (9133): v4l: disconnect kernel number from minor
The v4l core creates four different video devices (video, vbi, radio, vtx)
and each has its own range of minor numbers. However, modern devices keep
increasing the number of devices that they need so a maximum of 64 video
devices will not be enough in the future. In addition this scheme makes
it very hard to add new device types.
This patch disconnects the kernel number allocation (e.g. video0, video1,
etc.) from the actual minor number (just pick the first free minor).
This allows for much more flexibility in the future. However, it does
require the use of udev. For those who cannot use udev a new CONFIG option
was created that changes the allocation scheme back to the old behavior.
Thanks to Greg KH for suggesting this approach during the 2008 LPC.
In addition, several bugs were fixed in the ivtv and cx18 drivers: these
drivers try to allocate specific kernel numbers but that scheme contained
a bug which caused what should have been e.g. video17 to appear as e.g.
video2.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h
index d129b56..a0a6b41 100644
--- a/include/media/v4l2-dev.h
+++ b/include/media/v4l2-dev.h
@@ -18,20 +18,11 @@
#define VIDEO_MAJOR 81
-/* Minor device allocation */
-#define MINOR_VFL_TYPE_GRABBER_MIN 0
-#define MINOR_VFL_TYPE_GRABBER_MAX 63
-#define MINOR_VFL_TYPE_RADIO_MIN 64
-#define MINOR_VFL_TYPE_RADIO_MAX 127
-#define MINOR_VFL_TYPE_VTX_MIN 192
-#define MINOR_VFL_TYPE_VTX_MAX 223
-#define MINOR_VFL_TYPE_VBI_MIN 224
-#define MINOR_VFL_TYPE_VBI_MAX 255
-
#define VFL_TYPE_GRABBER 0
#define VFL_TYPE_VBI 1
#define VFL_TYPE_RADIO 2
#define VFL_TYPE_VTX 3
+#define VFL_TYPE_MAX 4
struct v4l2_ioctl_callbacks;
@@ -56,6 +47,7 @@
char name[32];
int vfl_type;
int minor;
+ u16 num;
/* attribute to differentiate multiple indices on one physical device */
int index;