On Tue, Sep 16, 2025 at 12:47:41PM +0800, Hermes Wu via B4 Relay wrote:
> From: Hermes Wu <[email protected]>
>
> When connect to a DP-to-HDMI device which does not connect
> to HDMI sink, it will report DPCD 00200h with SINK_COUNT = "0",
> and issue HPD_IRQ when SINK_COUNT change to "1".
>
> IT6505 can not recive HPD_IRQ before training done and driver will
> force HW enter training done state when connect to such devices.
>
> When HW is force to training done state and restart link training,
> bits FORCE_RETRAIN and MANUAL_TRAIN at REG_TRAIN_CTRL1 must be set
> at the same time to reset HW state.
>
> Signed-off-by: Hermes Wu <[email protected]>
> ---
> drivers/gpu/drm/bridge/ite-it6505.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
Fixes: b5c84a9edcd4 ("drm/bridge: add it6505 driver")
Reviewed-by: Dmitry Baryshkov <[email protected]>
--
With best wishes
Dmitry
