0bd860493f
This LTE modem (M.2 card) has a bug in its power management: there is some kind of race condition for U3 wake-up between the host and the device. The modem firmware sometimes crashes/locks when both events happen at the same time and the modem fully drops off the USB bus (and sometimes re-enumerates, sometimes just gets stuck until the next reboot). Tested with the modem wired to the XHCI controller on an AMD 3015Ce platform. Without the patch, the modem dropped of the USB bus 5 times in 3 days. With the quirk, it stayed connected for a week while the 'runtime_suspended_time' counter incremented as excepted. Signed-off-by: Vincent Palatin <vpalatin@chromium.org> Link: https://lore.kernel.org/r/20210319124802.2315195-1-vpalatin@chromium.org Cc: stable <stable@vger.kernel.org> 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.