The remaining drivers are mostly platform drivers. Name the
dir to reflect it.

It makes sense to latter break it into a few other dirs.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Add proper locking to the file operations, allowing for the removal
of the V4L2_FL_LOCK_ALL_FOPS flag.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This driver wasn't converted to the new clock framework
(e038ed50).
Signed-off-by: NJavier Martin <javier.martin@vista-silicon.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This patch adds new V4L2_CAP_VIDEO_M2M and V4L2_CAP_VIDEO_M2M_MPLANE
capability flags that are intended to be used for memory-to-memory (M2M)
devices, instead of ORed V4L2_CAP_VIDEO_CAPTURE and V4L2_CAP_VIDEO_OUTPUT.

V4L2_CAP_VIDEO_M2M flag is added at the drivers, CAPTURE and OUTPUT
capability flags are left untouched and will be removed in future,
after a transition period required for existing applications to be
adapted to check only for V4L2_CAP_VIDEO_M2M.
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NKamil Debski <k.debski@samsung.com>
Acked-by: NAndrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This used to be the default if the lock pointer was set, but now that lock is by
default only used for ioctl serialization. Those drivers that already used
core locking have this flag set explicitly, except for some drivers where
it was obvious that there was no need to serialize any file operations other
than ioctl.

The drivers that didn't need this flag were:

drivers/media/radio/dsbr100.c
drivers/media/radio/radio-isa.c
drivers/media/radio/radio-keene.c
drivers/media/radio/radio-miropcm20.c
drivers/media/radio/radio-mr800.c
drivers/media/radio/radio-tea5764.c
drivers/media/radio/radio-timb.c
drivers/media/video/vivi.c
sound/i2c/other/tea575x-tuner.c

The other drivers that use core locking and where it was not immediately
obvious that this flag wasn't needed were changed so that the flag is set
together with a comment that that driver needs work to avoid having to
set that flag. This will often involve taking the core lock in the fops
themselves.

Eventually this flag should go and it should not be used in new drivers.

There are a few reasons why we want to avoid core locking of non-ioctl
fops: in the case of mmap this can lead to a deadlock in rare situations
since when mmap is called the mmap_sem is held and it is possible for
other parts of the code to take that lock as well (copy_from_user()/copy_to_user()
perform a down_read(&mm->mmap_sem) when a page fault occurs).

It is very unlikely that that happens since the core lock serializes all
fops, but the kernel warns about it if lock validation is turned on.

For poll it is also undesirable to take the core lock as that can introduce
increased latency. The same is true for read/write.

While it was possible to make flags or something to turn on/off taking the
core lock for each file operation, in practice it is much simpler to just
not take it at all except for ioctl and leave it to the driver to take the
lock. There are only a handful fops compared to the zillion ioctls we have.

I also wanted to make it obvious which drivers still take the lock for all
fops, so that's why I chose to have drivers set it explicitly.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Acked-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Userptr can be very useful if this device
is requested to use video buffers allocated
by another processing device. So that
buffers don't need to be copied.
Signed-off-by: NJavier Martin <javier.martin@vista-silicon.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

i.MX2x SoCs have a PrP which is capable of resizing and format
conversion of video frames. This driver provides support for
resizing and format conversion from YUYV to YUV420.

This operation is of the utmost importance since some of these
SoCs like i.MX27 include an H.264 video codec which only
accepts YUV420 as input.
Reviewed-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NJavier Martin <javier.martin@vista-silicon.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>