Sonix-based cameras seem to require the host to commit video streaming
parameters before selecting the alternate endpoint. While most applications
issue a VIDIOC_S_FMT ioctl before starting streaming, this is not required
by the V4L2 specification.

The problem has been noticed on Ubuntu 8.10 with applications using libv4l.
The library blocks VIDIOC_S_FMT calls when the requested format is identical
to the currently selected format. As the driver commits video streaming
parameters when initialising the device, only the first run of a
libv4l-enabled application would succeed.

For the sake of completeness, experiment showed that the camera keeps sending
12 bytes isochronous packets (header only, no data) without toggling the FID
bit if video streaming parameters haven't been committed before selecting the
alternate endpoint.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Failed requests will now generate a one-time warning message instead of the
usual "Failed to query..." error, which should be more user-friendly. The
driver will also recover automatically from failed GET_MIN/GET_MAX requests
when the device is half-broken without requiring the MINMAX quirk (fully
broken devices still need the quirk).
Signed-off-by: NLaurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The inode argument was never used. Removing it from video_usercopy
brings the function pointer type of video_usercopy in line with similar
v4l2 functions, thus simplifying several drivers.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The inode parameter at v4l_compat_translate_ioctl() were just passed over several
places just to keep compatible with fops.ioctl. However, it weren't used anywere.

This patch gets hid of this unused parameter.

Cc: Laurent Pinchart <laurent.pinchart@skynet.be>
Cc: Mike Isely <isely@pobox.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

When streaming in a fixed size format the driver sets a flag in the uvc_queue
structure to drop incomplete incoming frames. The flag wasn't cleared when
switching to a variable size format, which resulted in a broken
'MJPEG after YUV'.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Use the new video_drvdata(filp) function where it is safe to do so.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The functions in a header should not belong to another module. The prio functions
belong to v4l2-common.c, so move them to v4l2-common.h.

The ioctl functions belong to v4l2-ioctl.c, so create a new v4l2-ioctl.h header
and move those functions to it.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/uvc/uvc_v4l2.c: In function `uvc_v4l2_mmap':
drivers/media/video/uvc/uvc_v4l2.c:1035: warning: 'buffer' might be used uninitialized in this function
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

Also remove some blank lines that were used to split compat code at -devel
tree.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

This driver supports video input devices compliant with the USB Video Class
specification. This means lots of currently manufactured webcams, and probably
most of the future ones.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>