• Hans Verkuil's avatar
    V4L/DVB (9133): v4l: disconnect kernel number from minor · dd89601d
    Hans Verkuil authored
    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: default avatarHans Verkuil <hverkuil@xs4all.nl>
    Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@redhat.com>
    dd89601d
v4l2-dev.c 10.5 KB