This is a note to let you know that I've just added the patch titled
Revert "drm/dp: Change AUX DPCD probe address from DPCD_REV to
LANE0_1_STATUS"
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
revert-drm-dp-change-aux-dpcd-probe-address-from-dpcd_rev-to-lane0_1_status.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <sta...@vger.kernel.org> know about it.
>From imre.d...@intel.com Tue Sep 2 13:42:52 2025
From: Imre Deak <imre.d...@intel.com>
Date: Thu, 28 Aug 2025 20:49:26 +0300
Subject: Revert "drm/dp: Change AUX DPCD probe address from DPCD_REV to
LANE0_1_STATUS"
To: <sta...@vger.kernel.org>
Cc: <intel-...@lists.freedesktop.org>, <dri-devel@lists.freedesktop.org>, Sasha
Levin <sas...@kernel.org>
Message-ID: <20250828174932.414566-1-imre.d...@intel.com>
From: Imre Deak <imre.d...@intel.com>
This reverts commit 2402adce8da4e7396b63b5ffa71e1fa16e5fe5c4 which is
commit a40c5d727b8111b5db424a1e43e14a1dcce1e77f upstream.
The upstream commit a40c5d727b8111b5db424a1e43e14a1dcce1e77f ("drm/dp:
Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS") the
reverted commit backported causes a regression, on one eDP panel at
least resulting in display flickering, described in detail at the Link:
below. The issue fixed by the upstream commit will need a different
solution, revert the backport for now.
Cc: intel-...@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Cc: Sasha Levin <sas...@kernel.org>
Link: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14558
Signed-off-by: Imre Deak <imre.d...@intel.com>
---
drivers/gpu/drm/drm_dp_helper.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -280,7 +280,7 @@ ssize_t drm_dp_dpcd_read(struct drm_dp_a
* We just have to do it before any DPCD access and hope that the
* monitor doesn't power down exactly after the throw away read.
*/
- ret = drm_dp_dpcd_access(aux, DP_AUX_NATIVE_READ, DP_LANE0_1_STATUS,
buffer,
+ ret = drm_dp_dpcd_access(aux, DP_AUX_NATIVE_READ, DP_DPCD_REV, buffer,
1);
if (ret != 1)
goto out;
Patches currently in stable-queue which might be from imre.d...@intel.com are
queue-5.4/revert-drm-dp-change-aux-dpcd-probe-address-from-dpcd_rev-to-lane0_1_status.patch
