Re: [PATCH v5] drm/msm/dp: power off DP phy at suspend

From: khsieh
Date: Thu Jun 03 2021 - 17:59:56 EST


On 2021-06-03 13:22, Stephen Boyd wrote:
Can you Cc dri-devel?

Sorry for dropping this cc.
Should I re submit this v5 with cc=dri-devel?



Quoting Kuogee Hsieh (2021-06-03 08:40:46)
Normal DP suspend operation contains two steps, display off followed
by dp suspend, to complete system wide suspending cycle if display is
up at that time. In this case, DP phy will be powered off at display
off. However there is an exception case that depending on the timing
of dongle plug in during system wide suspending, sometimes display off
procedure may be skipped and dp suspend was called directly. In this
case, dp phy is stay at powered on (phy->power_count = 1) so that at
next resume dp driver crash at main link clock enable due to phy is
not physically powered on. This patch will call dp_ctrl_off_link_stream()
to tear down main link and power off phy at dp_pm_suspend() if main link
had been brought up.