Commit Graph

829 Commits

Author SHA1 Message Date
Mauro Carvalho Chehab 76bf7087fb Merge commit 'v4.16-rc4~0' into patchwork
* commit 'v4.16-rc4~0': (900 commits)
  Linux 4.16-rc4
  memremap: fix softlockup reports at teardown
  libnvdimm: re-enable deep flush for pmem devices via fsync()
  MAINTAINERS: take over Kconfig maintainership
  vfio: disable filesystem-dax page pinning
  kconfig: fix line number in recursive inclusion error message
  Coccinelle: memdup: Fix typo in warning messages
  i2c: octeon: Prevent error message on bus error
  parisc: Reduce irq overhead when run in qemu
  parisc: Use cr16 interval timers unconditionally on qemu
  parisc: Check if secondary CPUs want own PDC calls
  parisc: Hide virtual kernel memory layout
  parisc: Fix ordering of cache and TLB flushes
  kconfig: Update ncurses package names for menuconfig
  kbuild/kallsyms: trivial typo fix
  kbuild: test --build-id linker flag by ld-option instead of cc-ldoption
  kbuild: drop superfluous GCC_PLUGINS_CFLAGS assignment
  kconfig: Don't leak choice names during parsing
  sh: fix build error for empty CONFIG_BUILTIN_DTB_SOURCE
  kconfig: set SYMBOL_AUTO to the symbol marked with defconfig_list
  ...
2018-03-05 07:39:06 -05:00
Hans Verkuil f437a7cb87 media: v4l2-subdev: implement VIDIOC_DBG_G_CHIP_INFO ioctl
The VIDIOC_DBG_G/S_REGISTER ioctls imply that VIDIOC_DBG_G_CHIP_INFO is also
present, since without that you cannot use v4l2-dbg.

Just like the implementation in v4l2-ioctl.c this can be implemented in the
core and no drivers need to be modified.

It also makes it possible for v4l2-compliance to properly test the
VIDIOC_DBG_G/S_REGISTER ioctls.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-26 09:33:39 -05:00
Hans Verkuil 3103c7b4ad media: v4l2-subdev: without controls return -ENOTTY
If the subdev did not define any controls, then return -ENOTTY if
userspace attempts to call these ioctls.

The control framework functions will return -EINVAL, not -ENOTTY if
vfh->ctrl_handler is NULL.

Several of these framework functions are also called directly from
drivers, so I don't want to change the error code there.

Found with vimc and v4l2-compliance.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-26 09:32:59 -05:00
Shuah Khan f61c7bd9c9 media: v4l2-core: v4l2-mc: Add SPDX license identifier
Replace GPL license statement with SPDX GPL-2.0 license identifier.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-26 07:42:03 -05:00
Mauro Carvalho Chehab e77c31ed60 media: videobuf2: fix build issues with vb2-trace
There was a trouble with vb2-trace: instead of being part of
VB2 core, it was stored at V4L2 videodev. That was wrong,
as it doesn't actually belong to V4L2 core.

Now that vb2 is not part of v4l2-core, its trace functions
should be moved altogether. So, move it to its rightful
place: at videobuf2-core.

That fixes those errors:
	drivers/media/common/videobuf2/videobuf2-core.o: In function `__read_once_size':
	./include/linux/compiler.h:183: undefined reference to `__tracepoint_vb2_buf_queue'
	./include/linux/compiler.h:183: undefined reference to `__tracepoint_vb2_buf_queue'
	./include/linux/compiler.h:183: undefined reference to `__tracepoint_vb2_buf_done'
	./include/linux/compiler.h:183: undefined reference to `__tracepoint_vb2_buf_done'
	./include/linux/compiler.h:183: undefined reference to `__tracepoint_vb2_qbuf'
	./include/linux/compiler.h:183: undefined reference to `__tracepoint_vb2_qbuf'
	./include/linux/compiler.h:183: undefined reference to `__tracepoint_vb2_dqbuf'
	./include/linux/compiler.h:183: undefined reference to `__tracepoint_vb2_dqbuf'
	drivers/media/common/videobuf2/videobuf2-core.o:(__jump_table+0x10): undefined reference to `__tracepoint_vb2_buf_queue'
	drivers/media/common/videobuf2/videobuf2-core.o:(__jump_table+0x28): undefined reference to `__tracepoint_vb2_buf_done'
	drivers/media/common/videobuf2/videobuf2-core.o:(__jump_table+0x40): undefined reference to `__tracepoint_vb2_qbuf'
	drivers/media/common/videobuf2/videobuf2-core.o:(__jump_table+0x58): undefined reference to `__tracepoint_vb2_dqbuf'

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-23 05:13:53 -05:00
Sakari Ailus 80dfd71c5a media: videobuf2: Add VIDEOBUF2_V4L2 Kconfig option for VB2 V4L2 part
Videobuf2 is now separate from V4L2 and can be now built without it, at
least in principle --- enabling videobuf2 in kernel configuration attempts
to compile videobuf2-v4l2.c but that will fail if CONFIG_VIDEO_V4L2 isn't
enabled.

Solve this by adding a separate Kconfig option for videobuf2-v4l2 and make
it a separate module as well. This means that drivers now need to choose
both the appropriate videobuf2 memory type
(VIDEOBUF2_{VMALLOC,DMA_CONTIG,DMA_SG}) and VIDEOBUF2_V4L2 if they need
both.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-23 05:12:55 -05:00
Tim Harvey c4455c265e media: v4l-ioctl: fix clearing pad for VIDIOC_DV_TIMINGS_CAP
The pad field was inadvertently cleared. Fix this. It's needed for subdevs.

Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
[hans.verkuil@cisco.com: make a proper commit message]
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-22 12:41:39 -05:00
Hans Verkuil 357a856a6c media: v4l2-dv-timings: add v4l2_hdmi_colorimetry()
Add the v4l2_hdmi_colorimetry() function so we have a single function
that determines the colorspace, YCbCr encoding, quantization range and
transfer function from the InfoFrame data.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-22 12:41:09 -05:00
Hans Verkuil 672de9a79c media: v4l2-common: create v4l2_g/s_parm_cap helpers
Create helpers to handle VIDIOC_G/S_PARM by querying the
g/s_frame_interval v4l2_subdev ops.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-22 12:25:33 -05:00
Hans Verkuil 7c8a940a5e media: v4l2-subdev: clear reserved fields
Clear the reserved fields for these ioctls according to the specification:

VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL
VIDIOC_SUBDEV_ENUM_FRAME_SIZE
VIDIOC_SUBDEV_ENUM_MBUS_CODE
VIDIOC_SUBDEV_G_CROP, VIDIOC_SUBDEV_S_CROP
VIDIOC_SUBDEV_G_FMT, VIDIOC_SUBDEV_S_FMT
VIDIOC_SUBDEV_G_FRAME_INTERVAL, VIDIOC_SUBDEV_S_FRAME_INTERVAL
VIDIOC_SUBDEV_G_SELECTION, VIDIOC_SUBDEV_S_SELECTION

Found with v4l2-compliance.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-22 12:23:44 -05:00
Hans Verkuil ddddfa78ac media: add SPDX license info
Replace the old license information with the corresponding SPDX
license for the remaining media drivers that Cisco authored.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-14 13:17:03 -05:00
Linus Torvalds a9a08845e9 vfs: do bulk POLL* -> EPOLL* replacement
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-11 14:34:03 -08:00
Linus Torvalds 68c5735eaa Merge tag 'media/v4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:

 - videobuf2 was moved to a media/common dir, as it is now used by the
   DVB subsystem too

 - Digital TV core memory mapped support interface

 - new sensor driver: ov7740

 - several improvements at ddbridge driver

 - new V4L2 driver: IPU3 CIO2 CSI-2 receiver unit, found on some Intel
   SoCs

 - new tuner driver: tda18250

 - finally got rid of all LIRC staging drivers

 - as we don't have old lirc drivers anymore, restruct the lirc device
   code

 - add support for UVC metadata

 - add a new staging driver for NVIDIA Tegra Video Decoder Engine

 - DVB kAPI headers moved to include/media

 - synchronize the kAPI and uAPI for the DVB subsystem, removing the gap
   for non-legacy APIs

 - reduce the kAPI gap for V4L2

 - lots of other driver enhancements, cleanups, etc.

* tag 'media/v4.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (407 commits)
  media: v4l2-compat-ioctl32.c: make ctrl_is_pointer work for subdevs
  media: v4l2-compat-ioctl32.c: refactor compat ioctl32 logic
  media: v4l2-compat-ioctl32.c: don't copy back the result for certain errors
  media: v4l2-compat-ioctl32.c: drop pr_info for unknown buffer type
  media: v4l2-compat-ioctl32.c: copy clip list in put_v4l2_window32
  media: v4l2-compat-ioctl32.c: fix ctrl_is_pointer
  media: v4l2-compat-ioctl32.c: copy m.userptr in put_v4l2_plane32
  media: v4l2-compat-ioctl32.c: avoid sizeof(type)
  media: v4l2-compat-ioctl32.c: move 'helper' functions to __get/put_v4l2_format32
  media: v4l2-compat-ioctl32.c: fix the indentation
  media: v4l2-compat-ioctl32.c: add missing VIDIOC_PREPARE_BUF
  media: v4l2-ioctl.c: don't copy back the result for -ENOTTY
  media: v4l2-ioctl.c: use check_fmt for enum/g/s/try_fmt
  media: vivid: fix module load error when enabling fb and no_error_inj=1
  media: dvb_demux: improve debug messages
  media: dvb_demux: Better handle discontinuity errors
  media: cxusb, dib0700: ignore XC2028_I2C_FLUSH
  media: ts2020: avoid integer overflows on 32 bit machines
  media: i2c: ov7740: use gpio/consumer.h instead of gpio.h
  media: entity: Add a nop variant of media_entity_cleanup
  ...
2018-02-06 11:27:48 -08:00
Hans Verkuil 273caa2600 media: v4l2-compat-ioctl32.c: make ctrl_is_pointer work for subdevs
If the device is of type VFL_TYPE_SUBDEV then vdev->ioctl_ops
is NULL so the 'if (!ops->vidioc_query_ext_ctrl)' check would crash.
Add a test for !ops to the condition.

All sub-devices that have controls will use the control framework,
so they do not have an equivalent to ops->vidioc_query_ext_ctrl.
Returning false if ops is NULL is the correct thing to do here.

Fixes: b8c601e8af ("v4l2-compat-ioctl32.c: fix ctrl_is_pointer")

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-31 03:09:04 -05:00
Linus Torvalds 168fe32a07 Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull poll annotations from Al Viro:
 "This introduces a __bitwise type for POLL### bitmap, and propagates
  the annotations through the tree. Most of that stuff is as simple as
  'make ->poll() instances return __poll_t and do the same to local
  variables used to hold the future return value'.

  Some of the obvious brainos found in process are fixed (e.g. POLLIN
  misspelled as POLL_IN). At that point the amount of sparse warnings is
  low and most of them are for genuine bugs - e.g. ->poll() instance
  deciding to return -EINVAL instead of a bitmap. I hadn't touched those
  in this series - it's large enough as it is.

  Another problem it has caught was eventpoll() ABI mess; select.c and
  eventpoll.c assumed that corresponding POLL### and EPOLL### were
  equal. That's true for some, but not all of them - EPOLL### are
  arch-independent, but POLL### are not.

  The last commit in this series separates userland POLL### values from
  the (now arch-independent) kernel-side ones, converting between them
  in the few places where they are copied to/from userland. AFAICS, this
  is the least disruptive fix preserving poll(2) ABI and making epoll()
  work on all architectures.

  As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and
  it will trigger only on what would've triggered EPOLLWRBAND on other
  architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered
  at all on sparc. With this patch they should work consistently on all
  architectures"

* 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits)
  make kernel-side POLL... arch-independent
  eventpoll: no need to mask the result of epi_item_poll() again
  eventpoll: constify struct epoll_event pointers
  debugging printk in sg_poll() uses %x to print POLL... bitmap
  annotate poll(2) guts
  9p: untangle ->poll() mess
  ->si_band gets POLL... bitmap stored into a user-visible long field
  ring_buffer_poll_wait() return value used as return value of ->poll()
  the rest of drivers/*: annotate ->poll() instances
  media: annotate ->poll() instances
  fs: annotate ->poll() instances
  ipc, kernel, mm: annotate ->poll() instances
  net: annotate ->poll() instances
  apparmor: annotate ->poll() instances
  tomoyo: annotate ->poll() instances
  sound: annotate ->poll() instances
  acpi: annotate ->poll() instances
  crypto: annotate ->poll() instances
  block: annotate ->poll() instances
  x86: annotate ->poll() instances
  ...
2018-01-30 17:58:07 -08:00
Daniel Mentz a1dfb4c48c media: v4l2-compat-ioctl32.c: refactor compat ioctl32 logic
The 32-bit compat v4l2 ioctl handling is implemented based on its 64-bit
equivalent. It converts 32-bit data structures into its 64-bit
equivalents and needs to provide the data to the 64-bit ioctl in user
space memory which is commonly allocated using
compat_alloc_user_space().

However, due to how that function is implemented, it can only be called
a single time for every syscall invocation.

Supposedly to avoid this limitation, the existing code uses a mix of
memory from the kernel stack and memory allocated through
compat_alloc_user_space().

Under normal circumstances, this would not work, because the 64-bit
ioctl expects all pointers to point to user space memory. As a
workaround, set_fs(KERNEL_DS) is called to temporarily disable this
extra safety check and allow kernel pointers. However, this might
introduce a security vulnerability: The result of the 32-bit to 64-bit
conversion is writeable by user space because the output buffer has been
allocated via compat_alloc_user_space(). A malicious user space process
could then manipulate pointers inside this output buffer, and due to the
previous set_fs(KERNEL_DS) call, functions like get_user() or put_user()
no longer prevent kernel memory access.

The new approach is to pre-calculate the total amount of user space
memory that is needed, allocate it using compat_alloc_user_space() and
then divide up the allocated memory to accommodate all data structures
that need to be converted.

An alternative approach would have been to retain the union type karg
that they allocated on the kernel stack in do_video_ioctl(), copy all
data from user space into karg and then back to user space. However, we
decided against this approach because it does not align with other
compat syscall implementations. Instead, we tried to replicate the
get_user/put_user pairs as found in other places in the kernel:

    if (get_user(clipcount, &up->clipcount) ||
        put_user(clipcount, &kp->clipcount)) return -EFAULT;

Notes from hans.verkuil@cisco.com:

This patch was taken from:
    https://github.com/LineageOS/android_kernel_samsung_apq8084/commit/97b733953c06e4f0398ade18850f0817778255f7

Clearly nobody could be bothered to upstream this patch or at minimum
tell us :-( We only heard about this a week ago.

This patch was rebased and cleaned up. Compared to the original I
also swapped the order of the convert_in_user arguments so that they
matched copy_in_user. It was hard to review otherwise. I also replaced
the ALLOC_USER_SPACE/ALLOC_AND_GET by a normal function.

Fixes: 6b5a9492ca ("v4l: introduce string control support.")

Signed-off-by: Daniel Mentz <danielmentz@google.com>
Co-developed-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-30 07:40:41 -05:00
Hans Verkuil d83a8243aa media: v4l2-compat-ioctl32.c: don't copy back the result for certain errors
Some ioctls need to copy back the result even if the ioctl returned
an error. However, don't do this for the error code -ENOTTY.
It makes no sense in that cases.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-30 07:35:16 -05:00
Hans Verkuil 169f24ca68 media: v4l2-compat-ioctl32.c: drop pr_info for unknown buffer type
There is nothing wrong with using an unknown buffer type. So
stop spamming the kernel log whenever this happens. The kernel
will just return -EINVAL to signal this.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-30 07:34:09 -05:00
Hans Verkuil a751be5b14 media: v4l2-compat-ioctl32.c: copy clip list in put_v4l2_window32
put_v4l2_window32() didn't copy back the clip list to userspace.
Drivers can update the clip rectangles, so this should be done.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-30 07:33:14 -05:00
Hans Verkuil b8c601e8af media: v4l2-compat-ioctl32.c: fix ctrl_is_pointer
ctrl_is_pointer just hardcoded two known string controls, but that
caused problems when using e.g. custom controls that use a pointer
for the payload.

Reimplement this function: it now finds the v4l2_ctrl (if the driver
uses the control framework) or it calls vidioc_query_ext_ctrl (if the
driver implements that directly).

In both cases it can now check if the control is a pointer control
or not.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-30 07:31:33 -05:00
Hans Verkuil 8ed5a59dcb media: v4l2-compat-ioctl32.c: copy m.userptr in put_v4l2_plane32
The struct v4l2_plane32 should set m.userptr as well. The same
happens in v4l2_buffer32 and v4l2-compliance tests for this.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-30 07:30:22 -05:00
Hans Verkuil 333b1e9f96 media: v4l2-compat-ioctl32.c: avoid sizeof(type)
Instead of doing sizeof(struct foo) use sizeof(*up). There even were
cases where 4 * sizeof(__u32) was used instead of sizeof(kp->reserved),
which is very dangerous when the size of the reserved array changes.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-30 07:28:35 -05:00
Hans Verkuil 486c521510 media: v4l2-compat-ioctl32.c: move 'helper' functions to __get/put_v4l2_format32
These helper functions do not really help. Move the code to the
__get/put_v4l2_format32 functions.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-30 07:26:55 -05:00
Hans Verkuil b7b957d429 media: v4l2-compat-ioctl32.c: fix the indentation
The indentation of this source is all over the place. Fix this.
This patch only changes whitespace.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-30 07:25:34 -05:00
Hans Verkuil 3ee6d04071 media: v4l2-compat-ioctl32.c: add missing VIDIOC_PREPARE_BUF
The result of the VIDIOC_PREPARE_BUF ioctl was never copied back
to userspace since it was missing in the switch.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: <stable@vger.kernel.org>      # for v4.15 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-01-30 07:24:06 -05:00