drm/ast: Move DP501-based connector code into separate helpers

Add helpers for DP501-based connectors. DP501 provides output via
DisplayPort. This used to be handled by the VGA connector code.

If a DP501 chip has been detected, ast will now create a DisplayPort
connector instead of a VGA connector.

Remove the DP501 code from ast_vga_connector_helper_get_modes(). Also
remove the call to drm_connector_update_edid_property(), which is
performed by drm_get_edid().
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220207141544.30015-9-tzimmermann@suse.de

drivers/gpu/drm/ast/ast_drv.h

@@ -165,6 +165,10 @@ struct ast_private {
 			struct drm_encoder encoder;
 			struct ast_vga_connector vga_connector;
 		} vga;
+		struct {
+			struct drm_encoder encoder;
+			struct drm_connector connector;
+		} dp501;
 	} output;
 
 	bool support_wide_screen;

drivers/gpu/drm/ast/ast_mode.c

@@ -40,6 +40,7 @@
 #include <drm/drm_gem_atomic_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_gem_vram_helper.h>
+#include <drm/drm_managed.h>
 #include <drm/drm_plane_helper.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
@@ -1259,30 +1260,22 @@ static int ast_crtc_init(struct drm_device *dev)
 static int ast_vga_connector_helper_get_modes(struct drm_connector *connector)
 {
 	struct ast_vga_connector *ast_vga_connector = to_ast_vga_connector(connector);
-	struct ast_private *ast = to_ast_private(connector->dev);
-	struct edid *edid = NULL;
-	bool flags = false;
-	int ret;
+	struct edid *edid;
+	int count;
 
-	if (ast->tx_chip_type == AST_TX_DP501) {
-		edid = kmalloc(128, GFP_KERNEL);
-		if (!edid)
-			return -ENOMEM;
+	if (!ast_vga_connector->i2c)
+		goto err_drm_connector_update_edid_property;
 
-		flags = ast_dp501_read_edid(connector->dev, (u8 *)edid);
-		if (!flags) {
-			kfree(edid);
-			edid = NULL;
-		}
-	}
-	if (!flags && ast_vga_connector->i2c)
 	edid = drm_get_edid(connector, &ast_vga_connector->i2c->adapter);
-	if (edid) {
-		drm_connector_update_edid_property(connector, edid);
-		ret = drm_add_edid_modes(connector, edid);
+	if (!edid)
+		goto err_drm_connector_update_edid_property;
+
+	count = drm_add_edid_modes(connector, edid);
 	kfree(edid);
-		return ret;
-	}
+
+	return count;
+
+err_drm_connector_update_edid_property:
 	drm_connector_update_edid_property(connector, NULL);
 	return 0;
 }
@@ -1354,6 +1347,92 @@ static int ast_vga_output_init(struct ast_private *ast)
 	return 0;
 }
 
+/*
+ * DP501 Connector
+ */
+
+static int ast_dp501_connector_helper_get_modes(struct drm_connector *connector)
+{
+	void *edid;
+	bool succ;
+	int count;
+
+	edid = kmalloc(EDID_LENGTH, GFP_KERNEL);
+	if (!edid)
+		goto err_drm_connector_update_edid_property;
+
+	succ = ast_dp501_read_edid(connector->dev, edid);
+	if (!succ)
+		goto err_kfree;
+
+	drm_connector_update_edid_property(connector, edid);
+	count = drm_add_edid_modes(connector, edid);
+	kfree(edid);
+
+	return count;
+
+err_kfree:
+	kfree(edid);
+err_drm_connector_update_edid_property:
+	drm_connector_update_edid_property(connector, NULL);
+	return 0;
+}
+
+static const struct drm_connector_helper_funcs ast_dp501_connector_helper_funcs = {
+	.get_modes = ast_dp501_connector_helper_get_modes,
+};
+
+static const struct drm_connector_funcs ast_dp501_connector_funcs = {
+	.reset = drm_atomic_helper_connector_reset,
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.destroy = drm_connector_cleanup,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static int ast_dp501_connector_init(struct drm_device *dev, struct drm_connector *connector)
+{
+	int ret;
+
+	ret = drm_connector_init(dev, connector, &ast_dp501_connector_funcs,
+				 DRM_MODE_CONNECTOR_DisplayPort);
+	if (ret)
+		return ret;
+
+	drm_connector_helper_add(connector, &ast_dp501_connector_helper_funcs);
+
+	connector->interlace_allowed = 0;
+	connector->doublescan_allowed = 0;
+
+	connector->polled = DRM_CONNECTOR_POLL_CONNECT;
+
+	return 0;
+}
+
+static int ast_dp501_output_init(struct ast_private *ast)
+{
+	struct drm_device *dev = &ast->base;
+	struct drm_crtc *crtc = &ast->crtc;
+	struct drm_encoder *encoder = &ast->output.dp501.encoder;
+	struct drm_connector *connector = &ast->output.dp501.connector;
+	int ret;
+
+	ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_TMDS);
+	if (ret)
+		return ret;
+	encoder->possible_crtcs = drm_crtc_mask(crtc);
+
+	ret = ast_dp501_connector_init(dev, connector);
+	if (ret)
+		return ret;
+
+	ret = drm_connector_attach_encoder(connector, encoder);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
 /*
  * Mode config
  */
@@ -1414,10 +1493,13 @@ int ast_mode_config_init(struct ast_private *ast)
 	switch (ast->tx_chip_type) {
 	case AST_TX_NONE:
 	case AST_TX_SIL164:
-	case AST_TX_DP501:
 		ret = ast_vga_output_init(ast);
 		break;
+	case AST_TX_DP501:
+		ret = ast_dp501_output_init(ast);
+		break;
 	}
+
 	if (ret)
 		return ret;