drm/msm/dp: employ bridge mechanism for display enable and disable

Currently the msm_dp_*** functions implement the same sequence which would
happen when drm_bridge is used. hence get rid of this intermediate layer
and align with the drm_bridge usage to avoid customized implementation.

Signed-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>

Changes in v2:
-- revise commit text
-- rename dp_bridge to msm_dp_bridge
-- delete empty functions

Changes in v3:
-- replace kzalloc() with devm_kzalloc()
-- replace __dp_display_enable() with dp_display_enable()
-- replace __dp_display_disable() with dp_display_disable()

Changes in v4:
-- msm_dp_bridge_init() called from msm_dp_modeset_init() same as dsi

Changes in v5:
-- delete attach, mode_fixup and pre_enable from dp_bridge_ops

Changes in v6:
-- rebase on msm-next-plus-fixes branch

Signed-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Link: https://lore.kernel.org/r/1638918933-2544-1-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Rob Clark <robdclark@chromium.org>

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

@@ -995,9 +995,6 @@ static void dpu_encoder_virt_mode_set(struct drm_encoder *drm_enc,
 
 	trace_dpu_enc_mode_set(DRMID(drm_enc));
 
-	if (drm_enc->encoder_type == DRM_MODE_ENCODER_TMDS)
-		msm_dp_display_mode_set(dpu_enc->dp, drm_enc, mode, adj_mode);
-
 	list_for_each_entry(conn_iter, connector_list, head)
 		if (conn_iter->encoder == drm_enc)
 			conn = conn_iter;
@@ -1173,14 +1170,6 @@ static void dpu_encoder_virt_enable(struct drm_encoder *drm_enc)
 
 	_dpu_encoder_virt_enable_helper(drm_enc);
 
-	if (drm_enc->encoder_type == DRM_MODE_ENCODER_TMDS) {
-		ret = msm_dp_display_enable(dpu_enc->dp, drm_enc);
-		if (ret) {
-			DPU_ERROR_ENC(dpu_enc, "dp display enable failed: %d\n",
-				ret);
-			goto out;
-		}
-	}
 	dpu_enc->enabled = true;
 
 out:
@@ -1206,11 +1195,6 @@ static void dpu_encoder_virt_disable(struct drm_encoder *drm_enc)
 	/* wait for idle */
 	dpu_encoder_wait_for_event(drm_enc, MSM_ENC_TX_COMPLETE);
 
-	if (drm_enc->encoder_type == DRM_MODE_ENCODER_TMDS) {
-		if (msm_dp_display_pre_disable(dpu_enc->dp, drm_enc))
-			DPU_ERROR_ENC(dpu_enc, "dp display push idle failed\n");
-	}
-
 	dpu_encoder_resource_control(drm_enc, DPU_ENC_RC_EVENT_PRE_STOP);
 
 	for (i = 0; i < dpu_enc->num_phys_encs; i++) {
@@ -1235,11 +1219,6 @@ static void dpu_encoder_virt_disable(struct drm_encoder *drm_enc)
 
 	DPU_DEBUG_ENC(dpu_enc, "encoder disabled\n");
 
-	if (drm_enc->encoder_type == DRM_MODE_ENCODER_TMDS) {
-		if (msm_dp_display_disable(dpu_enc->dp, drm_enc))
-			DPU_ERROR_ENC(dpu_enc, "dp display disable failed\n");
-	}
-
 	mutex_unlock(&dpu_enc->enc_lock);
 }
 

drivers/gpu/drm/msm/dp/dp_display.c

@@ -1481,6 +1481,18 @@ int msm_dp_modeset_init(struct msm_dp *dp_display, struct drm_device *dev,
 	}
 
 	priv->connectors[priv->num_connectors++] = dp_display->connector;
+
+	dp_display->bridge = msm_dp_bridge_init(dp_display, dev, encoder);
+	if (IS_ERR(dp_display->bridge)) {
+		ret = PTR_ERR(dp_display->bridge);
+		DRM_DEV_ERROR(dev->dev,
+			"failed to create dp bridge: %d\n", ret);
+		dp_display->bridge = NULL;
+		return ret;
+	}
+
+	priv->bridges[priv->num_bridges++] = dp_display->bridge;
+
 	return 0;
 }
 
@@ -1584,8 +1596,8 @@ int msm_dp_display_disable(struct msm_dp *dp, struct drm_encoder *encoder)
 }
 
 void msm_dp_display_mode_set(struct msm_dp *dp, struct drm_encoder *encoder,
-				struct drm_display_mode *mode,
-				struct drm_display_mode *adjusted_mode)
+				const struct drm_display_mode *mode,
+				const struct drm_display_mode *adjusted_mode)
 {
 	struct dp_display_private *dp_display;
 

drivers/gpu/drm/msm/dp/dp_display.h

@@ -13,6 +13,7 @@
 struct msm_dp {
 	struct drm_device *drm_dev;
 	struct device *codec_dev;
+	struct drm_bridge *bridge;
 	struct drm_connector *connector;
 	struct drm_encoder *encoder;
 	struct drm_bridge *panel_bridge;

drivers/gpu/drm/msm/dp/dp_drm.c

@@ -12,6 +12,14 @@
 #include "msm_kms.h"
 #include "dp_drm.h"
 
+
+struct msm_dp_bridge {
+	struct drm_bridge bridge;
+	struct msm_dp *dp_display;
+};
+
+#define to_dp_display(x)     container_of((x), struct msm_dp_bridge, bridge)
+
 struct dp_connector {
 	struct drm_connector base;
 	struct msm_dp *dp_display;
@@ -173,3 +181,71 @@ struct drm_connector *dp_drm_connector_init(struct msm_dp *dp_display)
 
 	return connector;
 }
+
+static void dp_bridge_mode_set(struct drm_bridge *drm_bridge,
+				const struct drm_display_mode *mode,
+				const struct drm_display_mode *adjusted_mode)
+{
+	struct msm_dp_bridge *dp_bridge = to_dp_display(drm_bridge);
+	struct msm_dp *dp_display = dp_bridge->dp_display;
+
+	msm_dp_display_mode_set(dp_display, drm_bridge->encoder, mode, adjusted_mode);
+}
+
+static void dp_bridge_enable(struct drm_bridge *drm_bridge)
+{
+	struct msm_dp_bridge *dp_bridge = to_dp_display(drm_bridge);
+	struct msm_dp *dp_display = dp_bridge->dp_display;
+
+	msm_dp_display_enable(dp_display, drm_bridge->encoder);
+}
+
+static void dp_bridge_disable(struct drm_bridge *drm_bridge)
+{
+	struct msm_dp_bridge *dp_bridge = to_dp_display(drm_bridge);
+	struct msm_dp *dp_display = dp_bridge->dp_display;
+
+	msm_dp_display_pre_disable(dp_display, drm_bridge->encoder);
+}
+
+static void dp_bridge_post_disable(struct drm_bridge *drm_bridge)
+{
+	struct msm_dp_bridge *dp_bridge = to_dp_display(drm_bridge);
+	struct msm_dp *dp_display = dp_bridge->dp_display;
+
+	msm_dp_display_disable(dp_display, drm_bridge->encoder);
+}
+
+static const struct drm_bridge_funcs dp_bridge_ops = {
+	.enable       = dp_bridge_enable,
+	.disable      = dp_bridge_disable,
+	.post_disable = dp_bridge_post_disable,
+	.mode_set     = dp_bridge_mode_set,
+};
+
+struct drm_bridge *msm_dp_bridge_init(struct msm_dp *dp_display, struct drm_device *dev,
+			struct drm_encoder *encoder)
+{
+	int rc;
+	struct msm_dp_bridge *dp_bridge;
+	struct drm_bridge *bridge;
+
+	dp_bridge = devm_kzalloc(dev->dev, sizeof(*dp_bridge), GFP_KERNEL);
+	if (!dp_bridge)
+		return ERR_PTR(-ENOMEM);
+
+	dp_bridge->dp_display = dp_display;
+
+	bridge = &dp_bridge->bridge;
+	bridge->funcs = &dp_bridge_ops;
+	bridge->encoder = encoder;
+
+	rc = drm_bridge_attach(encoder, bridge, NULL, DRM_BRIDGE_ATTACH_NO_CONNECTOR);
+	if (rc) {
+		DRM_ERROR("failed to attach bridge, rc=%d\n", rc);
+		kfree(dp_bridge);
+		return ERR_PTR(rc);
+	}
+
+	return bridge;
+}

drivers/gpu/drm/msm/msm_drv.h

@@ -389,8 +389,12 @@ int msm_dp_display_enable(struct msm_dp *dp, struct drm_encoder *encoder);
 int msm_dp_display_disable(struct msm_dp *dp, struct drm_encoder *encoder);
 int msm_dp_display_pre_disable(struct msm_dp *dp, struct drm_encoder *encoder);
 void msm_dp_display_mode_set(struct msm_dp *dp, struct drm_encoder *encoder,
-				struct drm_display_mode *mode,
-				struct drm_display_mode *adjusted_mode);
+				const struct drm_display_mode *mode,
+				const struct drm_display_mode *adjusted_mode);
+
+struct drm_bridge *msm_dp_bridge_init(struct msm_dp *dp_display,
+					struct drm_device *dev,
+					struct drm_encoder *encoder);
 void msm_dp_irq_postinstall(struct msm_dp *dp_display);
 void msm_dp_snapshot(struct msm_disp_state *disp_state, struct msm_dp *dp_display);
 
@@ -427,8 +431,8 @@ static inline int msm_dp_display_pre_disable(struct msm_dp *dp,
 }
 static inline void msm_dp_display_mode_set(struct msm_dp *dp,
 				struct drm_encoder *encoder,
-				struct drm_display_mode *mode,
-				struct drm_display_mode *adjusted_mode)
+				const struct drm_display_mode *mode,
+				const struct drm_display_mode *adjusted_mode)
 {
 }