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: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
A pending cleanup will mean that module.h won't be implicitly
everywhere anymore. Make sure the modular drivers in clocksource
are actually calling out for <module.h> explicitly in advance.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Standardize the remaining video drivers to return the API version
for the VIDIOC_QUERYCAP version, instead of a per-driver version.
Those drivers had the version updated more recently or are SoC
drivers. Even so, it doesn't sound a good idea to keep a per-driver
version control, so, let's use the per-subsystem version control
instead.
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The argument isn't used anymore by the functions, remove it.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
With the v4l2_i2c_new_subdev* functions now supporting loading modules
based on modaliases, remove the module names hardcoded in platform data
and pass a NULL module name to those functions.
All corresponding I2C modules have been checked, and all of them include
a module aliases table with names corresponding to what the sh_vou
platform data uses.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Missed a few init functions on non-Intel platforms the first time :-(
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
videobuf_waiton() must unlock and relock ext_lock if it has to wait.
For that to happen it needs the videobuf_queue pointer.
Don't attempt to unlock/relock q->ext_lock unless it was locked in the
first place.
vb->state has to be protected by a spinlock to be safe.
This patch is based on code from Mauro Carvalho Chehab <mchehab@redhat.com>.
[mchehab@redhat.com: add extra argument to a few missing places]
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
SH7724 datasheet specifies 480 pixels as the VOU maximum vertical resolution.
This is a bug in the datasheet, VOU also supports the full PAL resolution: 576
lines. Adjust the driver accordingly.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Endianness notation is meaningless for 8 bit YUYV codes. Switch pixel code
names to explicitly state the order of colour components in the data
stream.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
A number of SuperH Mobile SoCs, including sh7724, include a Video Output Unit.
This patch adds a video (V4L2) output driver for it. The driver uses v4l2-subdev
and mediabus APIs to interface to TV encoders.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Hans Verkuil