This reverts commit 2402adce8da4e7396b63b5ffa71e1fa16e5fe5c4.
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: [email protected]
Cc: [email protected]
Cc: Sasha Levin <[email protected]>
Link: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14558
Signed-off-by: Imre Deak <[email protected]>
---
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 4eabef5b86d0..ffc68d305afe 100644
--- 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_aux *aux, unsigned
int offset,
* 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;
--
2.49.1
