drm/meson: encoder_cvbs: switch to bridge with ATTACH_NO_CONNECTOR

Drop the local connector and move all callback to bridge funcs in order
to leverage the generic CVBS display connector.

This will also permit adding custom cvbs connectors for ADC based HPD
detection on some Amlogic SoC based boards.

Signed-off-by: Neil Armstrong <[e-mail]>
Acked-by: Sam Ravnborg <[e-mail]>
Acked-by: Martin Blumenstingl <[e-mail]>
[narmstrong: fixed diplay typo in commit log]
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/meson/meson_encoder_cvbs.c

···
 #include <linux/of_graph.h>
 
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_bridge_connector.h>
 #include <drm/drm_device.h>
 #include <drm/drm_edid.h>
 #include <drm/drm_probe_helper.h>
-#include <drm/drm_print.h>
+#include <drm/drm_simple_kms_helper.h>
 
 #include "meson_registers.h"
 #include "meson_vclk.h"
···
 
 struct meson_encoder_cvbs {
 	struct drm_encoder	encoder;
-	struct drm_connector	connector;
+	struct drm_bridge	bridge;
+	struct drm_bridge	*next_bridge;
 	struct meson_drm	*priv;
 };
-#define encoder_to_meson_encoder_cvbs(x) \
-	container_of(x, struct meson_encoder_cvbs, encoder)
 
-#define connector_to_meson_encoder_cvbs(x) \
-	container_of(x, struct meson_encoder_cvbs, connector)
+#define bridge_to_meson_encoder_cvbs(x) \
+	container_of(x, struct meson_encoder_cvbs, bridge)
 
 /* Supported Modes */
 
···
 	return NULL;
 }
 
-/* Connector */
-
-static void meson_cvbs_connector_destroy(struct drm_connector *connector)
+static int meson_encoder_cvbs_attach(struct drm_bridge *bridge,
+				     enum drm_bridge_attach_flags flags)
 {
-	drm_connector_cleanup(connector);
+	struct meson_encoder_cvbs *meson_encoder_cvbs =
+					bridge_to_meson_encoder_cvbs(bridge);
+
+	return drm_bridge_attach(bridge->encoder, meson_encoder_cvbs->next_bridge,
+				 &meson_encoder_cvbs->bridge, flags);
 }
 
-static enum drm_connector_status
-meson_cvbs_connector_detect(struct drm_connector *connector, bool force)
+static int meson_encoder_cvbs_get_modes(struct drm_bridge *bridge,
+					struct drm_connector *connector)
 {
-	/* FIXME: Add load-detect or jack-detect if possible */
-	return connector_status_connected;
-}
-
-static int meson_cvbs_connector_get_modes(struct drm_connector *connector)
-{
-	struct drm_device *dev = connector->dev;
+	struct meson_encoder_cvbs *meson_encoder_cvbs =
+					bridge_to_meson_encoder_cvbs(bridge);
+	struct meson_drm *priv = meson_encoder_cvbs->priv;
 	struct drm_display_mode *mode;
 	int i;
 
 	for (i = 0; i < MESON_CVBS_MODES_COUNT; ++i) {
 		struct meson_cvbs_mode *meson_mode = &meson_cvbs_modes[i];
 
-		mode = drm_mode_duplicate(dev, &meson_mode->mode);
+		mode = drm_mode_duplicate(priv->drm, &meson_mode->mode);
 		if (!mode) {
-			DRM_ERROR("Failed to create a new display mode\n");
+			dev_err(priv->dev, "Failed to create a new display mode\n");
 			return 0;
 		}
 
···
 	return i;
 }
 
-static int meson_cvbs_connector_mode_valid(struct drm_connector *connector,
-					   struct drm_display_mode *mode)
+static int meson_encoder_cvbs_mode_valid(struct drm_bridge *bridge,
+					const struct drm_display_info *display_info,
+					const struct drm_display_mode *mode)
 {
-	/* Validate the modes added in get_modes */
-	return MODE_OK;
+	if (meson_cvbs_get_mode(mode))
+		return MODE_OK;
+
+	return MODE_BAD;
 }
 
-static const struct drm_connector_funcs meson_cvbs_connector_funcs = {
-	.detect			= meson_cvbs_connector_detect,
-	.fill_modes		= drm_helper_probe_single_connector_modes,
-	.destroy		= meson_cvbs_connector_destroy,
-	.reset			= drm_atomic_helper_connector_reset,
-	.atomic_duplicate_state	= drm_atomic_helper_connector_duplicate_state,
-	.atomic_destroy_state	= drm_atomic_helper_connector_destroy_state,
-};
-
-static const
-struct drm_connector_helper_funcs meson_cvbs_connector_helper_funcs = {
-	.get_modes	= meson_cvbs_connector_get_modes,
-	.mode_valid	= meson_cvbs_connector_mode_valid,
-};
-
-/* Encoder */
-
-static void meson_encoder_cvbs_encoder_destroy(struct drm_encoder *encoder)
-{
-	drm_encoder_cleanup(encoder);
-}
-
-static const struct drm_encoder_funcs meson_encoder_cvbs_encoder_funcs = {
-	.destroy        = meson_encoder_cvbs_encoder_destroy,
-};
-
-static int meson_encoder_cvbs_encoder_atomic_check(struct drm_encoder *encoder,
+static int meson_encoder_cvbs_atomic_check(struct drm_bridge *bridge,
+					struct drm_bridge_state *bridge_state,
 					struct drm_crtc_state *crtc_state,
 					struct drm_connector_state *conn_state)
 {
···
 	return -EINVAL;
 }
 
-static void meson_encoder_cvbs_encoder_disable(struct drm_encoder *encoder)
+static void meson_encoder_cvbs_atomic_enable(struct drm_bridge *bridge,
+					     struct drm_bridge_state *bridge_state)
 {
-	struct meson_encoder_cvbs *meson_encoder_cvbs =
-					encoder_to_meson_encoder_cvbs(encoder);
-	struct meson_drm *priv = meson_encoder_cvbs->priv;
+	struct meson_encoder_cvbs *encoder_cvbs = bridge_to_meson_encoder_cvbs(bridge);
+	struct drm_atomic_state *state = bridge_state->base.state;
+	struct meson_drm *priv = encoder_cvbs->priv;
+	const struct meson_cvbs_mode *meson_mode;
+	struct drm_connector_state *conn_state;
+	struct drm_crtc_state *crtc_state;
+	struct drm_connector *connector;
 
-	/* Disable CVBS VDAC */
-	if (meson_vpu_is_compatible(priv, VPU_COMPATIBLE_G12A)) {
-		regmap_write(priv->hhi, HHI_VDAC_CNTL0_G12A, 0);
-		regmap_write(priv->hhi, HHI_VDAC_CNTL1_G12A, 0);
-	} else {
-		regmap_write(priv->hhi, HHI_VDAC_CNTL0, 0);
-		regmap_write(priv->hhi, HHI_VDAC_CNTL1, 8);
-	}
-}
+	connector = drm_atomic_get_new_connector_for_encoder(state, bridge->encoder);
+	if (WARN_ON(!connector))
+		return;
 
-static void meson_encoder_cvbs_encoder_enable(struct drm_encoder *encoder)
-{
-	struct meson_encoder_cvbs *meson_encoder_cvbs =
-					encoder_to_meson_encoder_cvbs(encoder);
-	struct meson_drm *priv = meson_encoder_cvbs->priv;
+	conn_state = drm_atomic_get_new_connector_state(state, connector);
+	if (WARN_ON(!conn_state))
+		return;
+
+	crtc_state = drm_atomic_get_new_crtc_state(state, conn_state->crtc);
+	if (WARN_ON(!crtc_state))
+		return;
+
+	meson_mode = meson_cvbs_get_mode(&crtc_state->adjusted_mode);
+	if (WARN_ON(!meson_mode))
+		return;
+
+	meson_venci_cvbs_mode_set(priv, meson_mode->enci);
+
+	/* Setup 27MHz vclk2 for ENCI and VDAC */
+	meson_vclk_setup(priv, MESON_VCLK_TARGET_CVBS,
+			 MESON_VCLK_CVBS, MESON_VCLK_CVBS,
+			 MESON_VCLK_CVBS, MESON_VCLK_CVBS,
+			 true);
 
 	/* VDAC0 source is not from ATV */
 	writel_bits_relaxed(VENC_VDAC_SEL_ATV_DMD, 0,
···
 	}
 }
 
-static void meson_encoder_cvbs_encoder_mode_set(struct drm_encoder *encoder,
-				   struct drm_display_mode *mode,
-				   struct drm_display_mode *adjusted_mode)
+static void meson_encoder_cvbs_atomic_disable(struct drm_bridge *bridge,
+					      struct drm_bridge_state *bridge_state)
 {
-	const struct meson_cvbs_mode *meson_mode = meson_cvbs_get_mode(mode);
 	struct meson_encoder_cvbs *meson_encoder_cvbs =
-					encoder_to_meson_encoder_cvbs(encoder);
+					bridge_to_meson_encoder_cvbs(bridge);
 	struct meson_drm *priv = meson_encoder_cvbs->priv;
 
-	if (meson_mode) {
-		meson_venci_cvbs_mode_set(priv, meson_mode->enci);
-
-		/* Setup 27MHz vclk2 for ENCI and VDAC */
-		meson_vclk_setup(priv, MESON_VCLK_TARGET_CVBS,
-				 MESON_VCLK_CVBS, MESON_VCLK_CVBS,
-				 MESON_VCLK_CVBS, MESON_VCLK_CVBS,
-				 true);
+	/* Disable CVBS VDAC */
+	if (meson_vpu_is_compatible(priv, VPU_COMPATIBLE_G12A)) {
+		regmap_write(priv->hhi, HHI_VDAC_CNTL0_G12A, 0);
+		regmap_write(priv->hhi, HHI_VDAC_CNTL1_G12A, 0);
+	} else {
+		regmap_write(priv->hhi, HHI_VDAC_CNTL0, 0);
+		regmap_write(priv->hhi, HHI_VDAC_CNTL1, 8);
 	}
 }
 
-static const struct drm_encoder_helper_funcs
-				meson_encoder_cvbs_encoder_helper_funcs = {
-	.atomic_check	= meson_encoder_cvbs_encoder_atomic_check,
-	.disable	= meson_encoder_cvbs_encoder_disable,
-	.enable		= meson_encoder_cvbs_encoder_enable,
-	.mode_set	= meson_encoder_cvbs_encoder_mode_set,
+static const struct drm_bridge_funcs meson_encoder_cvbs_bridge_funcs = {
+	.attach = meson_encoder_cvbs_attach,
+	.mode_valid = meson_encoder_cvbs_mode_valid,
+	.get_modes = meson_encoder_cvbs_get_modes,
+	.atomic_enable = meson_encoder_cvbs_atomic_enable,
+	.atomic_disable = meson_encoder_cvbs_atomic_disable,
+	.atomic_check = meson_encoder_cvbs_atomic_check,
+	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
+	.atomic_reset = drm_atomic_helper_bridge_reset,
 };
-
-static bool meson_encoder_cvbs_connector_is_available(struct meson_drm *priv)
-{
-	struct device_node *remote;
-
-	remote = of_graph_get_remote_node(priv->dev->of_node, 0, 0);
-	if (!remote)
-		return false;
-
-	of_node_put(remote);
-	return true;
-}
 
 int meson_encoder_cvbs_init(struct meson_drm *priv)
 {
 	struct drm_device *drm = priv->drm;
 	struct meson_encoder_cvbs *meson_encoder_cvbs;
 	struct drm_connector *connector;
-	struct drm_encoder *encoder;
+	struct device_node *remote;
 	int ret;
 
-	if (!meson_encoder_cvbs_connector_is_available(priv)) {
+	meson_encoder_cvbs = devm_kzalloc(priv->dev, sizeof(*meson_encoder_cvbs), GFP_KERNEL);
+	if (!meson_encoder_cvbs)
+		return -ENOMEM;
+
+	/* CVBS Connector Bridge */
+	remote = of_graph_get_remote_node(priv->dev->of_node, 0, 0);
+	if (!remote) {
 		dev_info(drm->dev, "CVBS Output connector not available\n");
 		return 0;
 	}
 
-	meson_encoder_cvbs = devm_kzalloc(priv->dev, sizeof(*meson_encoder_cvbs),
-				       GFP_KERNEL);
-	if (!meson_encoder_cvbs)
-		return -ENOMEM;
+	meson_encoder_cvbs->next_bridge = of_drm_find_bridge(remote);
+	if (!meson_encoder_cvbs->next_bridge) {
+		dev_err(priv->dev, "Failed to find CVBS Connector bridge\n");
+		return -EPROBE_DEFER;
+	}
+
+	/* CVBS Encoder Bridge */
+	meson_encoder_cvbs->bridge.funcs = &meson_encoder_cvbs_bridge_funcs;
+	meson_encoder_cvbs->bridge.of_node = priv->dev->of_node;
+	meson_encoder_cvbs->bridge.type = DRM_MODE_CONNECTOR_Composite;
+	meson_encoder_cvbs->bridge.ops = DRM_BRIDGE_OP_MODES;
+	meson_encoder_cvbs->bridge.interlace_allowed = true;
+
+	drm_bridge_add(&meson_encoder_cvbs->bridge);
 
 	meson_encoder_cvbs->priv = priv;
-	encoder = &meson_encoder_cvbs->encoder;
-	connector = &meson_encoder_cvbs->connector;
-
-	/* Connector */
-
-	drm_connector_helper_add(connector,
-				 &meson_cvbs_connector_helper_funcs);
-
-	ret = drm_connector_init(drm, connector, &meson_cvbs_connector_funcs,
-				 DRM_MODE_CONNECTOR_Composite);
-	if (ret) {
-		dev_err(priv->dev, "Failed to init CVBS connector\n");
-		return ret;
-	}
-
-	connector->interlace_allowed = 1;
 
 	/* Encoder */
-
-	drm_encoder_helper_add(encoder, &meson_encoder_cvbs_encoder_helper_funcs);
-
-	ret = drm_encoder_init(drm, encoder, &meson_encoder_cvbs_encoder_funcs,
-			       DRM_MODE_ENCODER_TVDAC, "meson_encoder_cvbs");
+	ret = drm_simple_encoder_init(priv->drm, &meson_encoder_cvbs->encoder,
+				      DRM_MODE_ENCODER_TVDAC);
 	if (ret) {
-		dev_err(priv->dev, "Failed to init CVBS encoder\n");
+		dev_err(priv->dev, "Failed to init CVBS encoder: %d\n", ret);
 		return ret;
 	}
 
-	encoder->possible_crtcs = BIT(0);
+	meson_encoder_cvbs->encoder.possible_crtcs = BIT(0);
 
-	drm_connector_attach_encoder(connector, encoder);
+	/* Attach CVBS Encoder Bridge to Encoder */
+	ret = drm_bridge_attach(&meson_encoder_cvbs->encoder, &meson_encoder_cvbs->bridge, NULL,
+				DRM_BRIDGE_ATTACH_NO_CONNECTOR);
+	if (ret) {
+		dev_err(priv->dev, "Failed to attach bridge: %d\n", ret);
+		return ret;
+	}
+
+	/* Initialize & attach Bridge Connector */
+	connector = drm_bridge_connector_init(priv->drm, &meson_encoder_cvbs->encoder);
+	if (IS_ERR(connector)) {
+		dev_err(priv->dev, "Unable to create CVBS bridge connector\n");
+		return PTR_ERR(connector);
+	}
+	drm_connector_attach_encoder(connector, &meson_encoder_cvbs->encoder);
 
 	return 0;
 }