On 2/27/2024 2:08 PM, Dmitry Baryshkov wrote:
This reverts commit e467e0bde881 ("drm/msm/dp: use
drm_bridge_hpd_notify() to report HPD status changes").
The commit changed the way how the MSM DP driver communicates
HPD-related events to the userspace. The mentioned commit made some of
the HPD events being reported earlier. This way userspace starts poking
around. It interacts in a bad way with the dp_bridge_detect and the
driver's state machine, ending up either with the very long delays
during hotplug detection or even inability of the DP driver to report
the display as connected.
A proper fix will involve redesigning of the HPD handling in the MSM DP
driver. It is underway, but it will be intrusive and can not be thought
about as a simple fix for the issue. Thus, revert the offending commit.
Yes, for fixing this on 6.9 I am fine with this.
I hope there were not other changes which were built on top of this. So
it will be better if we retest internal HPD case as well with this.
We will do that in a day or two and give Tested-by.
Fixes: e467e0bde881 ("drm/msm/dp: use drm_bridge_hpd_notify() to report HPD status changes")
Link: https://gitlab.freedesktop.org/drm/msm/-/issues/50
Reported-by: Johan Hovold <johan@xxxxxxxxxx>
Link: https://lore.kernel.org/r/Zd3YPGmrprxv-N-O@xxxxxxxxxxxxxxxxxxxx/
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
drivers/gpu/drm/msm/dp/dp_display.c | 20 ++++++++++++++++++--
1 file changed, 18 insertions(+), 2 deletions(-)
For the change itself,
Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
