Simplify ioctl handling by using video_ioctl2.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

We've got a bug report at disconnecting a Webcam, where the kernel
spews warnings like below:
  WARNING: CPU: 0 PID: 8385 at ../fs/sysfs/group.c:219 sysfs_remove_group+0x87/0x90()
  sysfs group c0b2350c not found for kobject 'event3'
  CPU: 0 PID: 8385 Comm: queue2:src Not tainted 3.16.2-1.gdcee397-default #1
  Hardware name: ASUSTeK Computer INC. A7N8X-E/A7N8X-E, BIOS ASUS A7N8X-E Deluxe ACPI BIOS Rev 1013  11/12/2004
    c08d0705 ddc75cbc c0718c5b ddc75ccc c024b654 c08c6d44 ddc75ce8 000020c1
    c08d0705 000000db c03d1ec7 c03d1ec7 00000009 00000000 c0b2350c d62c9064
    ddc75cd4 c024b6a3 00000009 ddc75ccc c08c6d44 ddc75ce8 ddc75cfc c03d1ec7
  Call Trace:
    [<c0205ba6>] try_stack_unwind+0x156/0x170
    [<c02046f3>] dump_trace+0x53/0x180
    [<c0205c06>] show_trace_log_lvl+0x46/0x50
    [<c0204871>] show_stack_log_lvl+0x51/0xe0
    [<c0205c67>] show_stack+0x27/0x50
    [<c0718c5b>] dump_stack+0x3e/0x4e
    [<c024b654>] warn_slowpath_common+0x84/0xa0
    [<c024b6a3>] warn_slowpath_fmt+0x33/0x40
    [<c03d1ec7>] sysfs_remove_group+0x87/0x90
    [<c05a2c54>] device_del+0x34/0x180
    [<c05e3989>] evdev_disconnect+0x19/0x50
    [<c05e06fa>] __input_unregister_device+0x9a/0x140
    [<c05e0845>] input_unregister_device+0x45/0x80
    [<f854b1d6>] uvc_delete+0x26/0x110 [uvcvideo]
    [<f84d66f8>] v4l2_device_release+0x98/0xc0 [videodev]
    [<c05a25bb>] device_release+0x2b/0x90
    [<c04ad8bf>] kobject_cleanup+0x6f/0x1a0
    [<f84d5453>] v4l2_release+0x43/0x70 [videodev]
    [<c0372f31>] __fput+0xb1/0x1b0
    [<c02650c1>] task_work_run+0x91/0xb0
    [<c024d845>] do_exit+0x265/0x910
    [<c024df64>] do_group_exit+0x34/0xa0
    [<c025a76f>] get_signal_to_deliver+0x17f/0x590
    [<c0201b6a>] do_signal+0x3a/0x960
    [<c02024f7>] do_notify_resume+0x67/0x90
    [<c071ebb5>] work_notifysig+0x30/0x3b
    [<b7739e60>] 0xb7739e5f
   ---[ end trace b1e56095a485b631 ]---

The cause is that uvc_status_cleanup() is called after usb_put_*() in
uvc_delete().  usb_put_*() removes the sysfs parent and eventually
removes the children recursively, so the later device_del() can't find
its sysfs.  The fix is simply rearrange the call orders in
uvc_delete() so that the child is removed before the parent.

Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=897736Reported-and-tested-by: NMartin Pluskal <mpluskal@suse.com>

Cc: <stable@vger.kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

This patch adds a quirk to force Y8 pixel format even if the camera reports
half-width YUYV.
Signed-off-by: NPhilipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Commit e93e7fd9 ("v4l2: uvcvideo: Allow
using larger buffers") reworked the buffer size sanity check at buffer
completion time to use the frame size instead of the allocated buffer
size. However, it introduced two bugs in doing so:

- it assigned the allocated buffer size to the frame_size field, instead
  of assigning the correct frame size

- it performed the assignment in the S_FMT handler, resulting in the
  frame_size field being uninitialized if the userspace application
  doesn't call S_FMT.

Fix both issues by removing the frame_size field and validating the
buffer size against the UVC video control dwMaxFrameSize.

Fixes: e93e7fd9 ("v4l2: uvcvideo: Allow using larger buffers")
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

A test in uvc_video_decode_isoc() checks whether an image has been
received from the camera completely. For this the data amount is compared
to the buffer length, which, however, doesn't have to be equal to the
image size. Switch to using formats .sizeimage field for an exact
expected image size.

[Renamed image_size to frame_size]
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

As reported on [1], this device needs this quirk to be able to
reliably initialise the webcam.

[1] http://ubuntuforums.org/showthread.php?t=2145996

Cc: stable@vger.kernel.org
Signed-off-by: NPaul Fertser <fercerpav@gmail.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

The uvcvideo webcam driver exposes the v4l2 control "Exposure (Absolute)"
which allows the user to control the exposure time of the webcam,
essentially controlling the brightness of the received image.  By default
the webcam automatically adjusts the exposure time automatically but the
if you set the control "Exposure, Auto"="Manual Mode" the user can fix
the exposure time.

Unfortunately it seems that the Logitech C920 has a firmware bug where
it will forget that it's in manual mode temporarily during initialisation.
This means that the camera doesn't respect the exposure time that the user
requested if they request it before starting to stream video.  They end up
with a video stream which is either too bright or too dark and must reset
the controls after video starts streaming.

This patch introduces the quirk UVC_QUIRK_RESTORE_CTRLS_ON_INIT which
causes the cached controls to be re-uploaded to the camera immediately
after initialising the camera.  This quirk is applied to the C920 to work
around this camera bug.
Signed-off-by: NWilliam Manley <will@williammanley.net>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Map V4L2_CID_TILT_SPEED and V4L2_CID_PAN_SPEED to the standard UVC
CT_PANTILT_RELATIVE_CONTROL terminal control request.

Tested by plugging a Logitech ConferenceCam C3000e USB camera
and controlling pan/tilt from the userspace using the VIDIOC_S_CTRL ioctl.
Verified that it can pan and tilt at the same time in both directions.
Signed-off-by: NVincent Palatin <vpalatin@chromium.org>
Reviewed-by: NPawel Osciak <posciak@chromium.org>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/usb/uvc/uvc_video.c:1466:38: warning: incorrect type in return expression (different base types)
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Since all the drivers that use `struct v4l2_fh' use the core
priority checking, the setting of the flag in the drivers can
be removed.
Signed-off-by: NRamakrishnan Muthukrishnan <ramakrmu@cisco.com>
Reviewed-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

timestamps in v4l2 buffers returned to userspace are updated in
uvc_video_clock_update() which uses timestamps fetched from
uvc_video_clock_decode() by calling unconditionally ktime_get_ts().

Hence setting the module clock param to realtime has no effect before
this patch.

This has been tested with ffmpeg:

ffmpeg -y -f v4l2 -input_format yuyv422 -video_size 640x480 -framerate 30 -i /dev/video0 \
 -f alsa -acodec pcm_s16le -ar 16000 -ac 1 -i default \
 -c:v libx264 -preset ultrafast \
 -c:a libfdk_aac \
 out.mkv

and inspecting the v4l2 input starting timestamp.

Cc: Stable <stable@vger.kernel.org>
Signed-off-by: NOlivier Langlois <olivier@trillion01.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Set error bit for incomplete buffers when end of buffer is detected by
FID toggling (for example when last transaction with EOF is lost).
This prevents passing incomplete buffers to the userspace.
Signed-off-by: NAnton Leontiev <bunder@t-25.ru>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

If a queue was canceled, then the buf_finish op was never called for the
pending buffers. So add this call to queue_cancel. Before calling buf_finish
set the buffer state to PREPARED, which is the correct state. That way the
states DONE and ERROR will only be seen in buf_finish if streaming is in
progress.

Since buf_finish can now be called from non-streaming state we need to
adapt the handful of drivers that actually need to know this.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Acked-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The buf_finish op should always work, so change the return type to void.
Update the few drivers that use it.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Acked-by: NPawel Osciak <pawel@osciak.com>
Reviewed-by: NPawel Osciak <pawel@osciak.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Add bayer 8-bit GUIDs to uvcvideo and associated them with the
corresponding V4L2 pixel formats.
Signed-off-by: NEdgar Thier <info@edgarthier.net>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The UVC specification uses alternate setting selection to notify devices
of stream start/stop. This breaks when using bulk-based devices, as the
video streaming interface has a single alternate setting in that case,
making video stream start and video stream stop events to appear
identical to the device. Bulk-based devices are thus not well supported
by UVC.

The webcam built in the Asus Zenbook UX302LA ignores the set interface
request and will keep the video stream enabled when the driver tries to
stop it. If USB autosuspend is enabled the device will then be suspended
and will crash, requiring a cold reboot.

USB trace capture showed that Windows sends a CLEAR_FEATURE(HALT)
request to the bulk endpoint when stopping the stream instead of
selecting alternate setting 0. The camera then behaves correctly, and
thus seems to require that behaviour.

Replace selection of alternate setting 0 with clearing of the endpoint
halt feature at video stream stop for bulk-based devices. Let's refrain
from blaming Microsoft this time, as it's not clear whether this
Windows-specific but USB-compliant behaviour was specifically developed
to handle bulkd-based UVC devices, or if the camera just took advantage
of it.

CC: stable@vger.kernel.org
Signed-off-by: NOleksij Rempel <linux@rempel-privat.de>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The UVC device provided timestamps are taken from the clock once the
exposure of the frame has begun, not when the reception of the frame would
have been finished as almost anywhere else. Show this to the user space by
using V4L2_BUF_FLAG_TSTAMP_SRC_SOE buffer flag.
Signed-off-by: NSakari Ailus <sakari.ailus@iki.fi>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The timestamp_type field used to contain only the timestamp type. Soon it
will be used for timestamp source flags as well. Rename the field
accordingly.

[m.chehab@samsung.com: do the change also to drivers/staging/media and at s2255]
Signed-off-by: NSakari Ailus <sakari.ailus@iki.fi>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

This patch enables the ioctl to create additional buffers on the
videobuf2 capture queue.

[laurent.pinchart@ideasonboard.com: Acquire privileges instead of just
checking them in VIDIOC_CREATE_BUFS implementation]
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The queue_setup handler takes an optional format argument that can be
used to allocate buffers for a format different than the current format.
The uvcvideo driver doesn't support changing the format when buffers
have been allocated, but there's no reason not to support allocating
buffers larger than the minimum size.

When the format argument isn't NULL verify that the requested image size
is large enough for the current format and use it for the buffer size.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

videobuf2 already ensures that the number of buffers will not exceed
VIDEO_MAX_FRAME, which is equal to our arbitraty limit of
UVC_MAX_VIDEO_BUFFERS. Remove the duplicate check.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Isochronous endpoints on devices with speed == USB_SPEED_WIRELESS can
have a max packet size ranging from 1-3584 bytes.  Add a case to
uvc_endpoint_max_bpi to handle USB_SPEED_WIRELESS.  Otherwise endpoints
for those devices will fall to the default case which masks off any
values > 2047.  This causes uvc_init_video to underestimate the
bandwidth available and fail to find a suitable alt setting for high
bandwidth video streams.
Signed-off-by: NThomas Pugliese <thomas.pugliese@gmail.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

x < constant implies x + unsigned < constant
That check just obfuscates the code
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Fix various spelling errors in strings and comments throughout the media
tree. The majority of these were found using Lucas De Marchi's codespell
tool.

[m.chehab@samsung.com: discard hunks with conflicts]
Signed-off-by: NJonathan McCrohan <jmccrohan@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Fix various spelling errors in strings and comments throughout the media
tree. The majority of these were found using Lucas De Marchi's codespell
tool.

[m.chehab@samsung.com: discard hunks with conflicts]
Signed-off-by: NJonathan McCrohan <jmccrohan@gmail.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

On this arch, usec is not unsigned long. So, we need to typecast,
in order to remove those warnings:
	drivers/media/usb/uvc/uvc_video.c: In function 'uvc_video_clock_update':
	drivers/media/usb/uvc/uvc_video.c:678:2: warning: format '%lu' expects argument of type 'long unsigned int', but argument 9 has type '__kernel_suseconds_t' [-Wformat]
	drivers/staging/media/lirc/lirc_serial.c: In function 'irq_handler':
	drivers/staging/media/lirc/lirc_serial.c:707:5: warning: format '%lx' expects argument of type 'long unsigned int', but argument 6 has type '__kernel_suseconds_t' [-Wformat]
	drivers/staging/media/lirc/lirc_serial.c:707:5: warning: format '%lx' expects argument of type 'long unsigned int', but argument 7 has type '__kernel_suseconds_t' [-Wformat]
	drivers/staging/media/lirc/lirc_serial.c:719:5: warning: format '%lx' expects argument of type 'long unsigned int', but argument 6 has type '__kernel_suseconds_t' [-Wformat]
	drivers/staging/media/lirc/lirc_serial.c:719:5: warning: format '%lx' expects argument of type 'long unsigned int', but argument 7 has type '__kernel_suseconds_t' [-Wformat]
	drivers/staging/media/lirc/lirc_serial.c:728:6: warning: format '%lx' expects argument of type 'long unsigned int', but argument 6 has type '__kernel_suseconds_t' [-Wformat]
	drivers/staging/media/lirc/lirc_serial.c:728:6: warning: format '%lx' expects argument of type 'long unsigned int', but argument 7 has type '__kernel_suseconds_t' [-Wformat]
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The pan/tilt absolute control value is signed value. If minimum value
is minus, It will be changed to plus by clamp_t() as commit 64ae9958.
([media] uvcvideo: Fix control value clamping for unsigned integer controls).
It leads to wrong setting of the control values. For example,
when min and max are -36000 and 36000, the setting value between of this range
is always 36000. So, its data type should be changed to signed.
Signed-off-by: NChanho Min <chanho.min@lge.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The camera doesn't implement GET_DEF on the video probe control and
can crash when it receives the request depending on timings. Set the
PROBE_DEF quirk to work around the problem.
Reported-by: NJürgen Liebmann <info@pirna-esw6.de>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

BugLink: http://bugs.launchpad.net/bugs/1217957
Add quirk for Dell SP2008WFP monitor: 05a9:2641
Signed-off-by: NJoseph Salisbury <joseph.salisbury@canonical.com>
Tested-by: NChristopher Townsend <christopher.townsend@canonical.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

The uvcvideo driver lost its dependency on VIDEO_V4L2 during the big
media directory reorganization. Add it back.
Reported-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Maintaining the users count using an atomic variable makes sure that
access to the counter won't be racy, but doesn't serialize access to the
operations protected by the counter. This creates a race condition that
could result in the status URB being submitted multiple times.
Use a mutex to protect the users count and serialize access to the
status start and stop operations.
Reported-by: NShawn Nematbakhsh <shawnn@chromium.org>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

BugLink: http://bugs.launchpad.net/bugs/1180409
OminiVision webcam 0x05a9:0x2643 needs the same UVC_QUIRK_PROBE_DEF
as other OmniVision models to work properly.
Signed-off-by: NJoseph Salisbury <joseph.salisbury@canonical.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

BugLink: https://bugs.launchpad.net/bugs/1168430
OminiVision webcam 0x05a9:0x264a (in Dell Studio Hybrid 140g) needs the
same UVC_QUIRK_PROBE_DEF as other OmniVision model to be recognized
consistently.
Signed-off-by: NKamal Mostafa <kamal@canonical.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

-ERANGE is the right error code when the value is outside of the menu
range, but -EINVAL must be reported for invalid values inside the range.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Not all drivers use monotonic timestamps. This patch adds a way to set the
timestamp type per every queue.
In addition, set proper timestamp type in drivers that I am sure that use
either MONOTONIC or COPY timestamps. Other drivers will correctly report
UNKNOWN timestamp type instead of assuming that all drivers use monotonic
timestamps.
Signed-off-by: NKamil Debski <k.debski@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Those optional operations are used to release and reacquire the queue
lock when videobuf2 needs to perform operations that sleep for a long
time, such as waiting for a buffer to be complete. Implement them to
avoid blocking qbuf or streamoff calls when a dqbuf is in progress.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Ming Lei reported:
IMO, there is a minor fault in the error handling path of
uvc_status_start() inside uvc_v4l2_open(), and the 'users' count should
have been decreased before usb_autopm_put_interface(). In theory, a [URB
resubmission] warning can be triggered when the device is opened just
between usb_autopm_put_interface() and atomic_dec(&stream->dev->users).
The fix is trivial.
Reported-by: NMing Lei <tom.leiming@gmail.com>
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This kind of memcpy() is error-prone. Its replacement with a struct
assignment is prefered because it's type-safe and much easier to read.
Signed-off-by: NPeter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: NEzequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The uvc_set_ctrl() calls don't write to the hardware. A failure at that
point thus leaves the device in a clean state, with no control modified.
Set the error_idx field to the count value to reflect that, as per the
V4L2 specification.
TRY_EXT_CTRLS is unchanged and the error_idx field must always be set to
the failed control index in that case.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Commit ba68c8530a263dc4de440fa10bb20a1c5b9d4ff5 (Partly revert "[media]
uvcvideo: Set error_idx properly for extended controls API failures")
missed two modifications. Clean them up.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>