drm/bridge: it6505: Power on downstream device in .atomic_enable

Send DPCD DP_SET_POWER_D0 command to the monitor in .atomic_enable
callback. Without this command, some monitors won't show up again after
changing the resolution.

Fixes: 46ca7da7 ("drm/bridge: it6505: Send DPCD SET_POWER to downstream")
Signed-off-by: Pin-Yen Lin <treapking@chromium.org>
Reviewed-by: Allen Chen <allen.chen@ite.com.tw>
Fixes: 46ca7da7 ("drm/bridge: it6505: Send DPCD SET_POWER to downstream")
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220714173715.v2.1.I85af54e9ceda74ec69f661852825845f983fc343@changeid

drivers/gpu/drm/bridge/ite-it6505.c

@@ -2945,6 +2945,9 @@ static void it6505_bridge_atomic_enable(struct drm_bridge *bridge,
 	if (ret)
 		dev_err(dev, "Failed to setup AVI infoframe: %d", ret);
 
+	it6505_drm_dp_link_set_power(&it6505->aux, &it6505->link,
+				     DP_SET_POWER_D0);
+
 	it6505_update_video_parameter(it6505, mode);
 
 	ret = it6505_send_video_infoframe(it6505, &frame);