5aba179c34
This happens when do stress test of uvc stream on/off which will
enable/disable endpoints. uvc has four tx requests, and may disable
endpoint between queue tx requests as following:
enable ep --> start qmu
queue tx request0
queue tx request1
queue tx request2 --> resume qmu
disable ep --> stop qmu may fail [1]
queue tx request3 --> will resume qmu, may cause qmu can't work
when enable ep next time [2]
[1]: when the tx fifo has some data to transmit, and
try to stop qmu (stop ep) meanwhile resume qmu (queue tx request),
it may cause stop qmu timeout, then can be fixed by flushing fifo
when stop qmu.
[2]: it resumes qmu again, shall stop qmu again.
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Reported-by: Min Guo <min.guo@mediatek.com>
Link: https://lore.kernel.org/r/20230119033322.21426-1-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.