mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-05 10:31:46 +09:00
d8cdbd0f6c
commit 43b26bdd2ee5cfca80939be910d5b23a50cd7f9d upstream. Starting BDB version 239, hdr_dpcd_refresh_timeout is introduced to backlight BDB data. Commit700034566d("drm/i915/bios: Define more BDB contents") updated the backlight BDB data accordingly. This broke the parsing of backlight BDB data in VBT for versions 236 - 238 (both inclusive) and hence the backlight controls are not responding on units with the concerned BDB version. backlight_control information has been present in backlight BDB data from at least BDB version 191 onwards, if not before. Hence this patch extracts the backlight_control information for BDB version 191 or newer. Tested on Chromebooks using Jasperlake SoC (reports bdb->version = 236). Tested on Chromebooks using Raptorlake SoC (reports bdb->version = 251). v2: removed checking the block size of the backlight BDB data [vsyrjala: this is completely safe thanks to commite163cfb4c9("drm/i915/bios: Make copies of VBT data blocks")] Fixes:700034566d("drm/i915/bios: Define more BDB contents") Cc: stable@vger.kernel.org Cc: Jani Nikula <jani.nikula@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Karthikeyan Ramasubramanian <kramasub@chromium.org> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240221180622.v2.1.I0690aa3e96a83a43b3fc33f50395d334b2981826@changeid Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> (cherry picked from commit c286f6a973c66c0d993ecab9f7162c790e7064c8) Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.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.