diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 00bc79f03039..0e2750cf85ef 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -328,29 +328,10 @@ intel_dp_aux_wait_done(struct intel_dp *intel_dp, bool has_aux_irq)
 	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 	struct drm_device *dev = intel_dig_port->base.base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
-	uint32_t ch_ctl = intel_dp->output_reg + 0x10;
+	uint32_t ch_ctl = intel_dp->aux_ch_ctl_reg;
 	uint32_t status;
 	bool done;
 
-	if (HAS_DDI(dev)) {
-		switch (intel_dig_port->port) {
-		case PORT_A:
-			ch_ctl = DPA_AUX_CH_CTL;
-			break;
-		case PORT_B:
-			ch_ctl = PCH_DPB_AUX_CH_CTL;
-			break;
-		case PORT_C:
-			ch_ctl = PCH_DPC_AUX_CH_CTL;
-			break;
-		case PORT_D:
-			ch_ctl = PCH_DPD_AUX_CH_CTL;
-			break;
-		default:
-			BUG();
-		}
-	}
-
 #define C (((status = I915_READ_NOTRACE(ch_ctl)) & DP_AUX_CH_CTL_SEND_BUSY) == 0)
 	if (has_aux_irq)
 		done = wait_event_timeout(dev_priv->gmbus_wait_queue, C,
@@ -370,11 +351,10 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
 		uint8_t *send, int send_bytes,
 		uint8_t *recv, int recv_size)
 {
-	uint32_t output_reg = intel_dp->output_reg;
 	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
 	struct drm_device *dev = intel_dig_port->base.base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
-	uint32_t ch_ctl = output_reg + 0x10;
+	uint32_t ch_ctl = intel_dp->aux_ch_ctl_reg;
 	uint32_t ch_data = ch_ctl + 4;
 	int i, ret, recv_bytes;
 	uint32_t status;
@@ -388,29 +368,6 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
 	 */
 	pm_qos_update_request(&dev_priv->pm_qos, 0);
 
-	if (HAS_DDI(dev)) {
-		switch (intel_dig_port->port) {
-		case PORT_A:
-			ch_ctl = DPA_AUX_CH_CTL;
-			ch_data = DPA_AUX_CH_DATA1;
-			break;
-		case PORT_B:
-			ch_ctl = PCH_DPB_AUX_CH_CTL;
-			ch_data = PCH_DPB_AUX_CH_DATA1;
-			break;
-		case PORT_C:
-			ch_ctl = PCH_DPC_AUX_CH_CTL;
-			ch_data = PCH_DPC_AUX_CH_DATA1;
-			break;
-		case PORT_D:
-			ch_ctl = PCH_DPD_AUX_CH_CTL;
-			ch_data = PCH_DPD_AUX_CH_DATA1;
-			break;
-		default:
-			BUG();
-		}
-	}
-
 	intel_dp_check_edp(intel_dp);
 	/* The clock divider is based off the hrawclk,
 	 * and would like to run at 2MHz. So, take the
@@ -2832,6 +2789,25 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
 	else
 		intel_connector->get_hw_state = intel_connector_get_hw_state;
 
+	intel_dp->aux_ch_ctl_reg = intel_dp->output_reg + 0x10;
+	if (HAS_DDI(dev)) {
+		switch (intel_dig_port->port) {
+		case PORT_A:
+			intel_dp->aux_ch_ctl_reg = DPA_AUX_CH_CTL;
+			break;
+		case PORT_B:
+			intel_dp->aux_ch_ctl_reg = PCH_DPB_AUX_CH_CTL;
+			break;
+		case PORT_C:
+			intel_dp->aux_ch_ctl_reg = PCH_DPC_AUX_CH_CTL;
+			break;
+		case PORT_D:
+			intel_dp->aux_ch_ctl_reg = PCH_DPD_AUX_CH_CTL;
+			break;
+		default:
+			BUG();
+		}
+	}
 
 	/* Set up the DDC bus. */
 	switch (port) {
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index febed9a010da..f21e22612bd8 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -366,6 +366,7 @@ struct intel_hdmi {
 
 struct intel_dp {
 	uint32_t output_reg;
+	uint32_t aux_ch_ctl_reg;
 	uint32_t DP;
 	uint8_t  link_configuration[DP_LINK_CONFIGURATION_SIZE];
 	bool has_audio;