drm/amd/display: Wait until OTG enable state is cleared

[Why]
Customer reported an issue that OS starts and stops device multiple times
during driver installation. Frequently disabling and enabling OTG may
prevent OTG from being safely disabled and cause incorrect configuration
upon the next enablement.

[How]
Add a wait until OTG_CURRENT_MASTER_EN_STATE is cleared as a short term
solution.

Reviewed-by: Dillon Varone <dillon.varone@amd.com>
Signed-off-by: TungYu Lu <tungyu.lu@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
TungYu Lu 2025-07-15 16:56:59 +08:00 committed by Alex Deucher
parent c31f486bc8
commit e7496c15d8

View File

@ -226,6 +226,11 @@ bool optc401_disable_crtc(struct timing_generator *optc)
REG_UPDATE(CONTROL,
VTG0_ENABLE, 0);
// wait until CRTC_CURRENT_MASTER_EN_STATE == 0
REG_WAIT(OTG_CONTROL,
OTG_CURRENT_MASTER_EN_STATE,
0, 10, 15000);
/* CRTC disabled, so disable clock. */
REG_WAIT(OTG_CLOCK_CONTROL,
OTG_BUSY, 0,