drm/i915/icl: Disable DDI function

This patch disables DDI function by writing to
TRANS_DDI_FUNC_CTL registers of DSI ports as part
of DSI disable sequence.

Signed-off-by: Madhav Chauhan <madhav.chauhan@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/b0088d643247135ba96943fa14625f5a43f43633.1540900289.git.jani.nikula@intel.com

diff --git a/drivers/gpu/drm/i915/icl_dsi.c b/drivers/gpu/drm/i915/icl_dsi.c
index 83c422d5976c58ec37dd252d78e8cf297b03535c..0041f57d3c0b06ad8154730e3310ccbbe9fe8bad 100644 (file)
--- a/drivers/gpu/drm/i915/icl_dsi.c
+++ b/drivers/gpu/drm/i915/icl_dsi.c
@@ -833,6 +833,14 @@ static void gen11_dsi_deconfigure_trancoder(struct intel_encoder *encoder)
                                10))
                        DRM_ERROR("DSI link not in ULPS\n");
        }
+
+       /* disable ddi function */
+       for_each_dsi_port(port, intel_dsi->ports) {
+               dsi_trans = dsi_port_to_transcoder(port);
+               tmp = I915_READ(TRANS_DDI_FUNC_CTL(dsi_trans));
+               tmp &= ~TRANS_DDI_FUNC_ENABLE;
+               I915_WRITE(TRANS_DDI_FUNC_CTL(dsi_trans), tmp);
+       }
 }
 
 static void __attribute__((unused)) gen11_dsi_disable(