dbe04e874d
commit ca871659ec1606d33b1e76de8d4cf924cf627e34 upstream.
Most eDP panel functions only work correctly when the panel is not in
self-refresh. In particular, analogix_dp_bridge_disable() tends to hit
AUX channel errors if the panel is in self-refresh.
Given the above, it appears that so far, this driver assumes that we are
never in self-refresh when it comes time to fully disable the bridge.
Prior to commit 846c7dfc1193 ("drm/atomic: Try to preserve the crtc
enabled state in drm_atomic_remove_fb, v2."), this tended to be true,
because we would automatically disable the pipe when framebuffers were
removed, and so we'd typically disable the bridge shortly after the last
display activity.
However, that is not guaranteed: an idle (self-refresh) display pipe may
be disabled, e.g., when switching CRTCs. We need to exit PSR first.
Stable notes: this is definitely a bugfix, and the bug has likely
existed in some form for quite a while. It may predate the "PSR helpers"
refactor, but the code looked very different before that, and it's
probably not worth rewriting the fix.
Cc: <stable@vger.kernel.org>
Fixes: 6c836d965bad ("drm/rockchip: Use the helpers for PSR")
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220228122522.v2.1.I161904be17ba14526f78536ccd78b85818449b51@changeid
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.