b1d76d16af
[ Upstream commit f28e32d3906eac2e1cb3291b448f0d528ec93996 ]
Currently in nouveau_connector_ddc_detect() and
nouveau_connector_detect_lvds(), we start the connector probing process
by releasing the previous EDID and informing DRM of the change. However,
since commit 5186421cbfe2 ("drm: Introduce epoch counter to
drm_connector") drm_connector_update_edid_property() actually checks
whether the new EDID we've specified is different from the previous one,
and updates the connector's epoch accordingly if it is. But, because we
always set the EDID to NULL first in nouveau_connector_ddc_detect() and
nouveau_connector_detect_lvds() we end up making DRM think that the EDID
changes every single time we do a connector probe - which isn't needed.
So, let's fix this by not clearing the EDID at the start of the
connector probing process, and instead simply changing or removing it
once near the end of the probing process. This will help prevent us from
sending unneeded hotplug events to userspace when nothing has actually
changed.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Ben Skeggs <bskeggs@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200826182456.322681-19-lyude@redhat.com
Stable-dep-of: 55b94bb8c424 ("drm/nouveau: add nv_encoder pointer check for NULL")
Signed-off-by: Sasha Levin <sashal@kernel.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.