drm/exynos/hdmi: add PHY power off signal handling

HDMI-PHY power off bit defaults to 0 in older HDMI versions.
In case of Exynos5433 it defaults to 1. To make code
consistent across all versions this bit is always unset/set in
power on/off sequences.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/exynos_hdmi.c

@@ -1754,6 +1754,8 @@ static void hdmi_enable(struct drm_encoder *encoder)
 
 	hdmi_set_refclk(hdata, true);
 
+	hdmi_reg_writemask(hdata, HDMI_PHY_CON_0, 0, HDMI_PHY_POWER_OFF_EN);
+
 	hdmi_conf_apply(hdata);
 
 	hdata->powered = true;
@@ -1786,6 +1788,8 @@ static void hdmi_disable(struct drm_encoder *encoder)
 
 	cancel_delayed_work(&hdata->hotplug_work);
 
+	hdmi_reg_writemask(hdata, HDMI_PHY_CON_0, ~0, HDMI_PHY_POWER_OFF_EN);
+
 	hdmi_set_refclk(hdata, false);
 
 	regmap_update_bits(hdata->pmureg, PMU_HDMI_PHY_CONTROL,