Those typos were left over from codespell check, on
my first pass or belong to code added after the time I
ran it.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Use codespell to fix lots of typos over frontends.
Manually verified to avoid false-positives.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The uvc driver uses this function to fill in bus_info for VIDIOC_QUERYCAP,
so use the same function when filling in the bus_info for the media device.
The current implementation only fills in part of the info. E.g. if the full
bus_info is usb-0000:01:00.0-1.4.2, then the media bus_info only has 1.4.2.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
drivers/media/usb/hdpvr/hdpvr-i2c.c: drivers/media/usb/hdpvr/hdpvr-i2c.c:78 hdpvr_i2c_read() warn: 'dev->i2c_buf' 4216624615462223872 can't fit into 127 '*data'
dev->i2c_buf is a char array, so you can just use dev->i2c_buf to get the
start address, no need to do &dev->i2c_buf, even though it is the same
address in C. It only confuses smatch.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Just like vb2 does, use u64 internally to store the timestamps
of the buffers. Only convert to timeval when interfacing with
userspace.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Just like vb2 does, use u64 internally to store the timestamps
of the buffers. Only convert to timeval when interfacing with
userspace.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Just like vb2 does, use u64 internally to store the timestamps
of the buffers. Only convert to timeval when interfacing with
userspace.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Just like vb2 does, use u64 internally to store the timestamps
of the buffers. Only convert to timeval when interfacing with
userspace.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The UVC video driver converts the timestamp from hardware specific unit
to one known by the kernel at the time when the buffer is dequeued. This
is fine in general, but the streamoff operation consists of the
following steps (among other things):
1. uvc_video_clock_cleanup --- the hardware clock sample array is
released and the pointer to the array is set to NULL,
2. buffers in active state are returned to the user and
3. buf_finish callback is called on buffers that are prepared.
buf_finish includes calling uvc_video_clock_update that accesses the
hardware clock sample array.
The above is serialised by a queue specific mutex. Address the problem
by skipping the clock conversion if the hardware clock sample array is
already released.
Fixes: 9c0863b1cc ("[media] vb2: call buf_finish from __queue_cancel")
Reported-by: Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>
Tested-by: Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
When initially testing the Camera Terminal Descriptor wTerminalType
field (buffer[4]), no mask is used. Later in the function, the MSB is
overloaded to store the descriptor subtype, and so a mask of 0x7fff
is used to check the type.
If a descriptor is specially crafted to set this overloaded bit in the
original wTerminalType field, the initial type check will fail (falling
through, without adjusting the buffer size), but the later type checks
will pass, assuming the buffer has been made suitably large, causing an
overflow.
Avoid this problem by checking for the MSB in the wTerminalType field.
If the bit is set, assume the descriptor is bad, and abort parsing it.
Originally reported here:
https://groups.google.com/forum/#!topic/syzkaller/Ot1fOE6v1d8
A similar (non-compiling) patch was provided at that time.
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Alistair Strachan <astrachan@google.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The COM3 register at address 0x0c already defaults to 0x10, the two bits
COM3[7:6] are set according to V4L2 controls by sethvflip later.
There is no need to set it multiple times during bridge initialization.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
This register is later overwritten by set_frame_rate anyway.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The video format, payload size, and frame size setup is video format
and frame size specific. Those registers are overwritten during
bridge_start anyway.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add support to pass through the sensor's native SGBRG8 bayer pattern,
allowing to cut the required USB bandwidth in half.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
In preparation for adding SGBRG8 as a second video format besides YUYV,
move video format specific register settings from the bridge_init array
into the bridge_start arrays.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
If a driver supports multiple pixel formats with the same frame size,
TRY_FMT will currently always return the first pixel format.
Fix this by adding pixelformat support to wxh_to_nearest_mode().
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
If a driver supports multiple pixel formats with the same frame size,
ENUM_FRAMEINTERVALS will currently only work for the first pixel format.
Fix this by adding pixelformat support to wxh_to_mode().
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
For short waits, usleep_range should be used instead of msleep,
see Documentation/timers/timers-howto.txt.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
In mt9m111_probe, m5602_write_bridge can timeout and return a negative
error value. The fix checks for this error and passes it upstream.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
In po1030_probe(), m5602_write_bridge() can timeout and return an error
value. The fix checks for the return value and propagates upstream
consistent with other usb drivers.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The fix checks if goto_low_power() fails, and if so, issues an error
message.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
do_command() may fail. The fix adds the missed return value of
do_command(). If it fails, returns its error code.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Control events can leak kernel memory since they do not fully zero the
event. The same code is present in both v4l2-ctrls.c and uvc_ctrl.c, so
fix both.
It appears that all other event code is properly zeroing the structure,
it's these two places.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reported-by: syzbot+4f021cf3697781dbd9fb@syzkaller.appspotmail.com
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
DMA cocherency slows the transfer down on systems without hardware
coherent DMA.
Instead we use noncocherent DMA memory and explicit sync at data receive
handler.
Based on previous commit the following performance benchmarks have been
carried out. Average memcpy() data transfer rate (rate) and handler
completion time (time) have been measured when running video stream at
640x480 resolution at 10fps.
x86_64 based system (Intel Core i5-3470). This platform has hardware
coherent DMA support and proposed change doesn't make big difference here.
* kmalloc: rate = (2.0 +- 0.4) GBps
time = (5.0 +- 3.0) usec
* usb_alloc_coherent: rate = (3.4 +- 1.2) GBps
time = (3.5 +- 3.0) usec
We see that the measurements agree within error ranges in this case.
So theoretically predicted performance downgrade cannot be reliably
measured here.
armv7l based system (TI AM335x BeagleBone Black @ 300MHz). This platform
has no hardware coherent DMA support. DMA coherence is implemented via
disabled page caching that slows down memcpy() due to memory controller
behaviour.
* kmalloc: rate = ( 94 +- 4) MBps
time = (101 +- 4) usec
* usb_alloc_coherent: rate = (28.1 +- 0.1) MBps
time = (341 +- 2) usec
Note, that quantative difference leads (this commit leads to 3.3 times
acceleration) to qualitative behavior change in this case. As it was
stated before, the video stream cannot be successfully received at AM335x
platforms with MUSB based USB host controller due to performance issues
[1].
[1] https://www.spinics.net/lists/linux-usb/msg165735.html
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
There were reports that PWC-based webcams don't work at some
embedded ARM platforms. [1] Isochronous transfer handler seems to
work too long leading to the issues in MUSB USB host subsystem.
Also note, that urb->giveback() handlers are still called with
disabled interrupts. In order to be able to measure performance of
PWC driver, traces are introduced in URB handler section.
[1] https://www.spinics.net/lists/linux-usb/msg165735.html
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
kmemdup has implemented the function that kmalloc() + memcpy().
We prefer to kmemdup rather than code opened implementation.
This issue was detected with the help of coccinelle.
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
CC: Tomoki Sekiyama <tomoki.sekiyama@gmail.com>
CC: linux-kernel@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
There is a spelling mistake in a pvr2_trace trace message, fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Interrupt is always present throughout life time of driver and
there is no dma element move this buffer to private area of driver.
Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The interrupt urb is killed but never freed add the function
Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
usb_control_msg returns in case of a successfully sent message the number
of sent bytes as a positive number. Don't use this value as a return value
for stk_camera_read_reg, as a non-zero return value is used as an error
condition in some cases when stk_camera_read_reg is called.
Signed-off-by: Andreas Pape <ap@ca-pape.de>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The ASUS A6VM notebook has a built in stk11xx webcam which is mounted
in a way that the video is vertically and horizontally flipped.
Therefore this notebook is added to the special handling in the driver
to automatically flip the video into the correct orientation.
Signed-off-by: Andreas Pape <ap@ca-pape.de>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Merge from Upstream after the latest media fixes branch, because we
need one patch that it is there.
* commit '0072a0c14d5b7cb72c611d396f143f5dcd73ebe2': (1108 commits)
ide: Change to use DEFINE_SHOW_ATTRIBUTE macro
ide: pmac: add of_node_put()
drivers/tty: add missing of_node_put()
drivers/sbus/char: add of_node_put()
sbus: char: add of_node_put()
Linux 4.20-rc5
PCI: Fix incorrect value returned from pcie_get_speed_cap()
MAINTAINERS: Update linux-mips mailing list address
ocfs2: fix potential use after free
mm/khugepaged: fix the xas_create_range() error path
mm/khugepaged: collapse_shmem() do not crash on Compound
mm/khugepaged: collapse_shmem() without freezing new_page
mm/khugepaged: minor reorderings in collapse_shmem()
mm/khugepaged: collapse_shmem() remember to clear holes
mm/khugepaged: fix crashes due to misaccounted holes
mm/khugepaged: collapse_shmem() stop if punched or truncated
mm/huge_memory: fix lockdep complaint on 32-bit i_size_read()
mm/huge_memory: splitting set mapping+index before unfreeze
mm/huge_memory: rename freeze_page() to unmap_page()
initramfs: clean old path before creating a hardlink
...
friio drivers is unused and un-compilable since
commit b30cc07de8 ("media: dvb-usb/friio, dvb-usb-v2/gl861: decompose
friio and merge with gl861"). Let's remove it.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Cc: Akihiro Tsukada <tskd2@yahoo.co.jp>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Use dvb-usb-v2 generic usb function for bulk transfers and simplify logic.
Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
lme2510_state exists for the entire duration of driver.
Move usb_buffer to lme2510_state removing the need for
lme2510_exit_int for removing the buffer.
Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Since 2018 some new revisions of RTL2832P based devices having
Sony CXD2837ER as a slave demodulator instead of Panasonic MN88473.
CXD2837ER handled in DVB_CXD2841ER module but it's has a lack of control.
So slave demod has to be reseted by GPIO0 before detecting to woke up
CXD2837ER.
Signed-off-by: Nikita Gerasimov <nikitych@yandex.ru>
Cc: Antti Palosaari <crope@iki.fi>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
A new iterator is available for processing UVC URB structures. This
simplifies the processing of the internal stream data.
Convert the manual loop iterators to the new helper, adding an index
helper to keep the existing debug print.
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
We have both uvc_init_video() and uvc_video_init() calls which can be
quite confusing to determine the process for each. Now that video
uvc_video_enable() has been renamed to uvc_video_start_streaming(),
adapt these calls to suit the new flow.
Rename uvc_init_video() to uvc_video_start_transfer() and
uvc_uninit_video() to uvc_video_stop_transfer().
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
uvc_video_enable() is used both to start and stop the video stream
object, however the single function entry point shares no code between
the two operations.
Split the function into two distinct calls, and rename to
uvc_video_start_streaming() and uvc_video_stop_streaming() as
appropriate.
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Newer high definition cameras, and cameras with multiple lenses such as
the range of stereo-vision cameras now available have ever increasing
data rates.
The inclusion of a variable length packet header in URB packets mean
that we must memcpy the frame data out to our destination 'manually'.
This can result in data rates of up to 2 gigabits per second being
processed.
To improve efficiency, and maximise throughput, handle the URB decode
processing through a work queue to move it from interrupt context, and
allow multiple processors to work on URBs in parallel.
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The streaming object is a key part of handling the UVC device. Although
not critical, we are currently missing a call to destroy the mutex on
clean up paths, and we are due to extend the objects complexity in the
near future.
Facilitate easy management of a stream object by creating a pair of
functions to handle creating and destroying the allocation. The new
uvc_stream_delete() function also performs the missing mutex_destroy()
operation.
Previously a failed streaming object allocation would cause
uvc_parse_streaming() to return -EINVAL, which is inappropriate. If the
constructor failes, we will instead return -ENOMEM.
While we're here, fix the trivial spelling error in the function banner
of uvc_delete().
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The buffer queue interface currently operates sequentially, processing
buffers after they have fully completed.
In preparation for supporting parallel tasks operating on the buffers,
we will need to support buffers being processed on multiple CPUs.
Adapt the uvc_queue_next_buffer() such that a reference count tracks the
active use of the buffer, returning the buffer to the VB2 stack at
completion.
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Both uvc_start_streaming(), and uvc_stop_streaming() are called from
userspace context, with interrupts enabled. As such, they do not need to
save the IRQ state, and can use spin_lock_irq() and spin_unlock_irq()
respectively.
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The URB completion operation obtains the current buffer by reading
directly into the queue internal interface.
Protect this queue abstraction by providing a helper
uvc_queue_get_current_buffer() which can be used by both the decode
task, and the uvc_queue_next_buffer() functions.
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The URB completion handlers currently reference the stream context.
Now that each URB has its own context structure, convert the decode (and
one encode) functions to utilise this context for URB management.
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
We currently store three separate arrays for each URB reference we hold.
Objectify the data needed to track URBs into a single uvc_urb structure,
allowing better object management and tracking of the URB.
All accesses to the data pointers through stream, are converted to use a
uvc_urb pointer for consistency.
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Fix name of the Hybrid T USB XS em28xx card, should be Cinergy.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Currently, disconnecting a USB webcam while it is in use prints out a
number of warnings, such as:
WARNING: CPU: 2 PID: 3118 at /build/linux-ezBi1T/linux-4.8.0/fs/sysfs/group.c:237 sysfs_remove_group+0x8b/0x90
sysfs group ffffffffa7cd0780 not found for kobject 'event13'
This has been noticed before. [0]
This is because of the order in which things are torn down.
If there are no streams active during a USB disconnect:
- uvc_disconnect() is invoked via device_del() through the bus
notifier mechanism.
- this calls uvc_unregister_video().
- uvc_unregister_video() unregisters the video device for each
stream,
- because there are no streams open, it calls uvc_delete()
- uvc_delete() calls uvc_status_cleanup(), which cleans up the status
input device.
- uvc_delete() calls media_device_unregister(), which cleans up the
media device
- uvc_delete(), uvc_unregister_video() and uvc_disconnect() all
return, and we end up back in device_del().
- device_del() then cleans up the sysfs folder for the camera with
dpm_sysfs_remove(). Because uvc_status_cleanup() and
media_device_unregister() have already been called, this all works
nicely.
If, on the other hand, there *are* streams active during a USB disconnect:
- uvc_disconnect() is invoked
- this calls uvc_unregister_video()
- uvc_unregister_video() unregisters the video device for each
stream,
- uvc_unregister_video() and uvc_disconnect() return, and we end up
back in device_del().
- device_del() then cleans up the sysfs folder for the camera with
dpm_sysfs_remove(). Because the status input device and the media
device are children of the USB device, this also deletes their
sysfs folders.
- Sometime later, the final stream is closed, invoking uvc_release().
- uvc_release() calls uvc_delete()
- uvc_delete() calls uvc_status_cleanup(), which cleans up the status
input device. Because the sysfs directory has already been removed,
this causes a WARNing.
- uvc_delete() calls media_device_unregister(), which cleans up the
media device. Because the sysfs directory has already been removed,
this causes another WARNing.
To fix this, we need to make sure the devices are always unregistered
before the end of uvc_disconnect(). To this, move the unregistration
into the disconnect path:
- split uvc_status_cleanup() into two parts, one on disconnect that
unregisters and one on delete that frees.
- move v4l2_device_unregister() and media_device_unregister() into
the disconnect path.
[0]: https://lkml.org/lkml/2016/12/8/657
[Renamed uvc_input_cleanup() to uvc_input_unregister()]
Signed-off-by: Daniel Axtens <dja@axtens.net>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Mauro Carvalho Chehab