On Fri, Jan 03, 2025 at 02:58:15PM +0200, Abel Vesa wrote: > According to the DisplayPort standard, LTTPRs have two operating > modes: > - non-transparent - it replies to DPCD LTTPR field specific AUX > requests, while passes through all other AUX requests > - transparent - it passes through all AUX requests. > > Switching between this two modes is done by the DPTX by issuing > an AUX write to the DPCD PHY_REPEATER_MODE register. > > Add a generic helper that allows switching between these modes. > > Also add a generic wrapper for the helper that handles the explicit > disabling of non-transparent mode and its disable->enable sequence > mentioned in the DP Standard v2.0 section 3.6.6.1. Do this in order > to move this handling out of the vendor specific driver implementation > into the generic framework. > > Tested-by: Johan Hovold <johan+linaro@xxxxxxxxxx> > Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxx> > --- > drivers/gpu/drm/display/drm_dp_helper.c | 61 +++++++++++++++++++++++++++++++++ > include/drm/display/drm_dp_helper.h | 2 ++ > 2 files changed, 63 insertions(+) > Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> -- With best wishes Dmitry
