V4L/DVB (12429): v4l2-ioctl: fix G_STD and G_PARM default handlers

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The v4l core supplies default handlers for G_STD and G_PARM. However, both
default handlers are buggy.

This patch fixes the following:

1) If no g_std is supplied and current_norm == 0, then this driver does not
   support TV video standards (e.g. a radio or webcam driver). Return
   -EINVAL. This ensures that there is no bogus VIDIOC_G_STD support for
   such drivers.

2) The default VIDIOC_G_PARM handler used current_norm instead of first
   checking if the driver supported g_std and calling that to get the norm.
   It also didn't check if current_norm was 0, since in that case the driver
   does not support TV standards (or no standard was set at all) and the
   default handler should return -EINVAL.

Note that I am very unhappy with these default handlers: I think they
basically behave like some very strange and unexpected side-effect.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

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This commit is contained in:

Hans Verkuil 2009-08-07 07:28:16 -03:00 • committed by Mauro Carvalho Chehab

parent 99362e1ece

commit 9bedc7f7fe

1 changed files with 12 additions and 3 deletions

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drivers/media/video/v4l2-ioctl.c

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