1c20d672e3
commit f74c7557ed0d321947e8bb4e9d47c1013f8b2227 upstream.
Some EC based devices (e.g. Fingerpint MCU) can jump to RO part of the
firmware (intentionally or due to device reboot). The RO part doesn't
change during the device lifecycle, so it won't support newer version
of EC_CMD_GET_NEXT_EVENT command.
Function cros_ec_query_all() is responsible for finding maximum
supported MKBP event version. It's usually called when the device is
running RW part of the firmware, so the command version can be
potentially higher than version supported by the RO.
The problem was fixed by updating maximum supported version when the
device returns EC_RES_INVALID_VERSION (mapped to -ENOPROTOOPT). That way
the kernel will use highest common version supported by RO and RW.
Fixes: 3300fdd630d4 ("platform/chrome: cros_ec: handle MKBP more events flag")
Cc: <stable@vger.kernel.org> # 5.10+
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Patryk Duda <pdk@semihalf.com>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20220802154128.21175-1-pdk@semihalf.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.