From fcd4f0444b3b2774638d12eeb78870464ce1a0a5 Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Thu, 28 Aug 2025 20:49:27 +0300 Subject: [PATCH] Revert "drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS" This reverts commit 89d17a2d89a83c5b7643ca934651a3f9229e4734 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-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org Cc: Sasha Levin Link: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14558 Signed-off-by: Imre Deak Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_dp_helper.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index ba8ab1dc4912..6ba16db77500 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -299,7 +299,7 @@ ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset, * monitor doesn't power down exactly after the throw away read. */ if (!aux->is_remote) { - ret = drm_dp_dpcd_access(aux, DP_AUX_NATIVE_READ, DP_LANE0_1_STATUS, + ret = drm_dp_dpcd_access(aux, DP_AUX_NATIVE_READ, DP_DPCD_REV, buffer, 1); if (ret != 1) goto out;