69fa0e23a6
commit 18846627ef1210dcd55d65342b055ea97a46ffff upstream.
Reinstate commit 88b065943cb5 ("drm/i915/dsi: Do display on
sequence later on icl+"), for the most part. Turns out some
machines (eg. Chuwi Minibook X) really do need that updated order.
It is also the order the Windows driver uses.
However we can't just undo the revert since that would again
break Lenovo 82TQ. After staring at the VBT sequences for both
machines I've concluded that the Lenovo 82TQ sequences look
somewhat broken:
- INIT_OTP is not present at all
- what should be in INIT_OTP is found in DISPLAY_ON
- what should be in DISPLAY_ON is found in BACKLIGHT_ON
(along with the actual backlight stuff)
The Chuwi Minibook X on the other hand has a full complement
of sequences in its VBT.
So let's try to deal with the broken sequences in the
Lenovo 82TQ VBT by simply swapping the (non-existent)
INIT_OTP sequence with the DISPLAY_ON sequence. Thus we
execute DISPLAY_ON when intending to execute INIT_OTP,
and execute nothing at all when intending to execute
DISPLAY_ON. That should be 100% equivalent to the
revert, for such broken VBTs.
Cc: stable@vger.kernel.org
Fixes: 6992eb815d08 ("Revert "drm/i915/dsi: Do display on sequence later on icl+"")
References: https://gitlab.freedesktop.org/drm/intel/-/issues/10071
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/10334
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240305083659.8396-1-ville.syrjala@linux.intel.com
Acked-by: Jani Nikula <jani.nikula@intel.com>
(cherry picked from commit 94ae4612ea336bfc3c12b3fc68467c6711a4f39b)
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.