drm/i915: Remove unneeded disconnect in TypeC legacy port mode

Disconnecting the TypeC PHY when the port is in legacy mode is not
necessary:
- BSpec doesn't specify a disconnect sequence for legacy mode.
- The use of the PHY is dedicated for the display in legacy mode.
- We keep the PHY always connected during runtime as well in legacy
  mode.

We disconnect the PHY when needed during a disabling modeset for the
port, so we can also remove the disconnect call from the destroy hook.

Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190628143635.22066-23-imre.deak@intel.com

drivers/gpu/drm/i915/display/intel_ddi.c

@@ -3946,31 +3946,12 @@ static int intel_ddi_compute_config(struct intel_encoder *encoder,
 	return 0;
 }
 
-static void intel_ddi_encoder_suspend(struct intel_encoder *encoder)
-{
-	struct intel_digital_port *dig_port = enc_to_dig_port(&encoder->base);
-
-	intel_dp_encoder_suspend(encoder);
-
-	/*
-	 * TODO: disconnect also from USB DP alternate mode once we have a
-	 * way to handle the modeset restore in that mode during resume
-	 * even if the sink has disappeared while being suspended.
-	 */
-	if (dig_port->tc_legacy_port)
-		icl_tc_phy_disconnect(dig_port);
-}
-
 static void intel_ddi_encoder_destroy(struct drm_encoder *encoder)
 {
 	struct intel_digital_port *dig_port = enc_to_dig_port(encoder);
-	struct drm_i915_private *i915 = to_i915(encoder->dev);
 
 	intel_dp_encoder_flush_work(encoder);
 
-	if (intel_port_is_tc(i915, dig_port->base.port))
-		icl_tc_phy_disconnect(dig_port);
-
 	drm_encoder_cleanup(encoder);
 	kfree(dig_port);
 }
@@ -4262,7 +4243,7 @@ void intel_ddi_init(struct drm_i915_private *dev_priv, enum port port)
 	intel_encoder->update_pipe = intel_ddi_update_pipe;
 	intel_encoder->get_hw_state = intel_ddi_get_hw_state;
 	intel_encoder->get_config = intel_ddi_get_config;
-	intel_encoder->suspend = intel_ddi_encoder_suspend;
+	intel_encoder->suspend = intel_dp_encoder_suspend;
 	intel_encoder->get_power_domains = intel_ddi_get_power_domains;
 	intel_encoder->type = INTEL_OUTPUT_DDI;
 	intel_encoder->power_domain = intel_port_to_power_domain(port);

drivers/gpu/drm/i915/display/intel_tc.c

@@ -243,10 +243,12 @@ static void icl_tc_phy_connect(struct intel_digital_port *dig_port,
  * See the comment at the connect function. This implements the Disconnect
  * Flow.
  */
-void icl_tc_phy_disconnect(struct intel_digital_port *dig_port)
+static void icl_tc_phy_disconnect(struct intel_digital_port *dig_port)
 {
 	switch (dig_port->tc_mode) {
 	case TC_PORT_LEGACY:
+		/* Nothing to do, we never disconnect from legacy mode */
+		break;
 	case TC_PORT_DP_ALT:
 		icl_tc_phy_set_safe_mode(dig_port, true);
 		dig_port->tc_mode = TC_PORT_TBT_ALT;

drivers/gpu/drm/i915/display/intel_tc.h

@@ -10,8 +10,6 @@
 #include <linux/mutex.h>
 #include "intel_drv.h"
 
-void icl_tc_phy_disconnect(struct intel_digital_port *dig_port);
-
 bool intel_tc_port_connected(struct intel_digital_port *dig_port);
 u32 intel_tc_port_get_lane_mask(struct intel_digital_port *dig_port);
 int intel_tc_port_fia_max_lane_count(struct intel_digital_port *dig_port);