drm/i915: start adding dp mst audio

(This patch is developed by Dave Airlie <airlied@redhat.com> originally)

This patch adds support for DP MST audio in i915.

Enable audio codec when DP MST is enabled if has_audio flag is set.
Disable audio codec when DP MST is disabled if has_audio flag is set.

Another separated patches to support DP MST audio will be implemented
in audio driver.

v2:
Rebased.

Signed-off-by: Libin Yang <libin.yang@linux.intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Lyude <cpaul@redhat.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1474334681-22690-6-git-send-email-dhinakaran.pandiyan@intel.com

drivers/gpu/drm/i915/i915_debugfs.c

@@ -2888,6 +2888,20 @@ static void intel_dp_info(struct seq_file *m,
 				&intel_dp->aux);
 }
 
+static void intel_dp_mst_info(struct seq_file *m,
+			  struct intel_connector *intel_connector)
+{
+	struct intel_encoder *intel_encoder = intel_connector->encoder;
+	struct intel_dp_mst_encoder *intel_mst =
+		enc_to_mst(&intel_encoder->base);
+	struct intel_digital_port *intel_dig_port = intel_mst->primary;
+	struct intel_dp *intel_dp = &intel_dig_port->dp;
+	bool has_audio = drm_dp_mst_port_has_audio(&intel_dp->mst_mgr,
+					intel_connector->port);
+
+	seq_printf(m, "\taudio support: %s\n", yesno(has_audio));
+}
+
 static void intel_hdmi_info(struct seq_file *m,
 			    struct intel_connector *intel_connector)
 {
@@ -2930,7 +2944,10 @@ static void intel_connector_info(struct seq_file *m,
 	switch (connector->connector_type) {
 	case DRM_MODE_CONNECTOR_DisplayPort:
 	case DRM_MODE_CONNECTOR_eDP:
-		intel_dp_info(m, intel_connector);
+		if (intel_encoder->type == INTEL_OUTPUT_DP_MST)
+			intel_dp_mst_info(m, intel_connector);
+		else
+			intel_dp_info(m, intel_connector);
 		break;
 	case DRM_MODE_CONNECTOR_LVDS:
 		if (intel_encoder->type == INTEL_OUTPUT_LVDS)

drivers/gpu/drm/i915/intel_ddi.c

@@ -2227,6 +2227,19 @@ void intel_ddi_prepare_link_retrain(struct intel_dp *intel_dp)
 	udelay(600);
 }
 
+bool intel_ddi_is_audio_enabled(struct drm_i915_private *dev_priv,
+				 struct intel_crtc *intel_crtc)
+{
+	u32 temp;
+
+	if (intel_display_power_is_enabled(dev_priv, POWER_DOMAIN_AUDIO)) {
+		temp = I915_READ(HSW_AUD_PIN_ELD_CP_VLD);
+		if (temp & AUDIO_OUTPUT_ENABLE(intel_crtc->pipe))
+			return true;
+	}
+	return false;
+}
+
 void intel_ddi_get_config(struct intel_encoder *encoder,
 			  struct intel_crtc_state *pipe_config)
 {
@@ -2292,11 +2305,8 @@ void intel_ddi_get_config(struct intel_encoder *encoder,
 		break;
 	}
 
-	if (intel_display_power_is_enabled(dev_priv, POWER_DOMAIN_AUDIO)) {
-		temp = I915_READ(HSW_AUD_PIN_ELD_CP_VLD);
-		if (temp & AUDIO_OUTPUT_ENABLE(intel_crtc->pipe))
-			pipe_config->has_audio = true;
-	}
+	pipe_config->has_audio =
+		intel_ddi_is_audio_enabled(dev_priv, intel_crtc);
 
 	if (encoder->type == INTEL_OUTPUT_EDP && dev_priv->vbt.edp.bpp &&
 	    pipe_config->pipe_bpp > dev_priv->vbt.edp.bpp) {

drivers/gpu/drm/i915/intel_dp_mst.c

@@ -37,6 +37,8 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
 	struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
 	struct intel_digital_port *intel_dig_port = intel_mst->primary;
 	struct intel_dp *intel_dp = &intel_dig_port->dp;
+	struct intel_connector *connector =
+		to_intel_connector(conn_state->connector);
 	struct drm_atomic_state *state;
 	int bpp;
 	int lane_count, slots;
@@ -59,6 +61,8 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
 
 	state = pipe_config->base.state;
 
+	if (drm_dp_mst_port_has_audio(&intel_dp->mst_mgr, connector->port))
+		pipe_config->has_audio = true;
 	mst_pbn = drm_dp_calc_pbn_mode(adjusted_mode->crtc_clock, bpp);
 
 	pipe_config->pbn = mst_pbn;
@@ -84,6 +88,7 @@ static void intel_mst_disable_dp(struct intel_encoder *encoder,
 	struct intel_dp *intel_dp = &intel_dig_port->dp;
 	struct intel_connector *connector =
 		to_intel_connector(old_conn_state->connector);
+	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
 	int ret;
 
 	DRM_DEBUG_KMS("%d\n", intel_dp->active_mst_links);
@@ -94,6 +99,10 @@ static void intel_mst_disable_dp(struct intel_encoder *encoder,
 	if (ret) {
 		DRM_ERROR("failed to update payload %d\n", ret);
 	}
+	if (old_crtc_state->has_audio) {
+		intel_audio_codec_disable(encoder);
+		intel_display_power_put(dev_priv, POWER_DOMAIN_AUDIO);
+	}
 }
 
 static void intel_mst_post_disable_dp(struct intel_encoder *encoder,
@@ -206,6 +215,12 @@ static void intel_mst_enable_dp(struct intel_encoder *encoder,
 	ret = drm_dp_check_act_status(&intel_dp->mst_mgr);
 
 	ret = drm_dp_update_payload_part2(&intel_dp->mst_mgr);
+	if (pipe_config->has_audio) {
+		DRM_DEBUG_DRIVER("Enabling DP audio on pipe %c\n",
+				 pipe_name(intel_mst->pipe));
+		intel_display_power_get(dev_priv, POWER_DOMAIN_AUDIO);
+		intel_audio_codec_enable(encoder);
+	}
 }
 
 static bool intel_dp_mst_enc_get_hw_state(struct intel_encoder *encoder,
@@ -228,6 +243,9 @@ static void intel_dp_mst_enc_get_config(struct intel_encoder *encoder,
 	enum transcoder cpu_transcoder = pipe_config->cpu_transcoder;
 	u32 temp, flags = 0;
 
+	pipe_config->has_audio =
+		intel_ddi_is_audio_enabled(dev_priv, crtc);
+
 	temp = I915_READ(TRANS_DDI_FUNC_CTL(cpu_transcoder));
 	if (temp & TRANS_DDI_PHSYNC)
 		flags |= DRM_MODE_FLAG_PHSYNC;

drivers/gpu/drm/i915/intel_drv.h

@@ -1156,6 +1156,8 @@ bool intel_ddi_pll_select(struct intel_crtc *crtc,
 void intel_ddi_set_pipe_settings(struct drm_crtc *crtc);
 void intel_ddi_prepare_link_retrain(struct intel_dp *intel_dp);
 bool intel_ddi_connector_get_hw_state(struct intel_connector *intel_connector);
+bool intel_ddi_is_audio_enabled(struct drm_i915_private *dev_priv,
+				 struct intel_crtc *intel_crtc);
 void intel_ddi_get_config(struct intel_encoder *encoder,
 			  struct intel_crtc_state *pipe_config);
 struct intel_encoder *