drm/msm/dp: add audio support for Display Port on MSM

Introduce audio support for Display Port on MSM chipsets.
This change integrates DP audio sub-module with the main
Display Port platform driver.

In addition, this change leverages hdmi_codec_ops to expose
the operations to the audio driver.

Changes in v2: fix up a compilation issue on drm-next branch
Changes in v3: none
Changes in v4: none
Changes in v5: none
Changes in v6: rebase on top of latest patchset of dependency

Signed-off-by: Abhinav Kumar <abhinavk@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/Makefile

@@ -111,7 +111,8 @@ msm-$(CONFIG_DRM_MSM_DP)+= dp/dp_aux.o \
 	dp/dp_parser.o \
 	dp/dp_power.o \
 	dp/dp_pll.o \
-	dp/dp_pll_10nm.o
+	dp/dp_pll_10nm.o \
+	dp/dp_audio.o
 
 msm-$(CONFIG_DRM_FBDEV_EMULATION) += msm_fbdev.o
 msm-$(CONFIG_COMMON_CLK) += disp/mdp4/mdp4_lvds_pll.o

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c

@@ -1112,6 +1112,13 @@ static void _dpu_encoder_virt_enable_helper(struct drm_encoder *drm_enc)
 		return;
 	}
 
+
+	if (dpu_enc->disp_info.intf_type == DRM_MODE_CONNECTOR_DisplayPort &&
+		dpu_enc->cur_master->hw_mdptop &&
+		dpu_enc->cur_master->hw_mdptop->ops.intf_audio_select)
+		dpu_enc->cur_master->hw_mdptop->ops.intf_audio_select(
+			dpu_enc->cur_master->hw_mdptop);
+
 	_dpu_encoder_update_vsync_source(dpu_enc, &dpu_enc->disp_info);
 
 	if (dpu_enc->disp_info.intf_type == DRM_MODE_ENCODER_DSI &&