diff --git a/android/bazel.go b/android/bazel.go
index cf27cb4..3bc104d 100644
--- a/android/bazel.go
+++ b/android/bazel.go
@@ -15,6 +15,7 @@
 package android
 
 import (
+	"android/soong/bazel"
 	"fmt"
 	"io/ioutil"
 	"path/filepath"
@@ -24,34 +25,33 @@
 	"github.com/google/blueprint/proptools"
 )
 
-type bazelModuleProperties struct {
-	// The label of the Bazel target replacing this Soong module. When run in conversion mode, this
-	// will import the handcrafted build target into the autogenerated file. Note: this may result in
-	// a conflict due to duplicate targets if bp2build_available is also set.
-	Label *string
-
-	// If true, bp2build will generate the converted Bazel target for this module. Note: this may
-	// cause a conflict due to the duplicate targets if label is also set.
-	//
-	// This is a bool pointer to support tristates: true, false, not set.
-	//
-	// To opt-in a module, set bazel_module: { bp2build_available: true }
-	// To opt-out a module, set bazel_module: { bp2build_available: false }
-	// To defer the default setting for the directory, do not set the value.
-	Bp2build_available *bool
-}
-
 // Properties contains common module properties for Bazel migration purposes.
 type properties struct {
 	// In USE_BAZEL_ANALYSIS=1 mode, this represents the Bazel target replacing
 	// this Soong module.
-	Bazel_module bazelModuleProperties
+	Bazel_module bazel.BazelModuleProperties
 }
 
+type namespacedVariableProperties map[string]interface{}
+
 // BazelModuleBase contains the property structs with metadata for modules which can be converted to
 // Bazel.
 type BazelModuleBase struct {
 	bazelProperties properties
+
+	// namespacedVariableProperties is used for soong_config_module_type support
+	// in bp2build. Soong config modules allow users to set module properties
+	// based on custom product variables defined in Android.bp files. These
+	// variables are namespaced to prevent clobbering, especially when set from
+	// Makefiles.
+	namespacedVariableProperties namespacedVariableProperties
+
+	// baseModuleType is set when this module was created from a module type
+	// defined by a soong_config_module_type. Every soong_config_module_type
+	// "wraps" another module type, e.g. a soong_config_module_type can wrap a
+	// cc_defaults to a custom_cc_defaults, or cc_binary to a custom_cc_binary.
+	// This baseModuleType is set to the wrapped module type.
+	baseModuleType string
 }
 
 // Bazelable is specifies the interface for modules that can be converted to Bazel.
@@ -63,6 +63,12 @@
 	ConvertWithBp2build(ctx BazelConversionContext) bool
 	convertWithBp2build(ctx BazelConversionContext, module blueprint.Module) bool
 	GetBazelBuildFileContents(c Config, path, name string) (string, error)
+
+	// For namespaced config variable support
+	namespacedVariableProps() namespacedVariableProperties
+	setNamespacedVariableProps(props namespacedVariableProperties)
+	BaseModuleType() string
+	SetBaseModuleType(string)
 }
 
 // BazelModule is a lightweight wrapper interface around Module for Bazel-convertible modules.
@@ -82,6 +88,22 @@
 	return &b.bazelProperties
 }
 
+func (b *BazelModuleBase) namespacedVariableProps() namespacedVariableProperties {
+	return b.namespacedVariableProperties
+}
+
+func (b *BazelModuleBase) setNamespacedVariableProps(props namespacedVariableProperties) {
+	b.namespacedVariableProperties = props
+}
+
+func (b *BazelModuleBase) BaseModuleType() string {
+	return b.baseModuleType
+}
+
+func (b *BazelModuleBase) SetBaseModuleType(baseModuleType string) {
+	b.baseModuleType = baseModuleType
+}
+
 // HasHandcraftedLabel returns whether this module has a handcrafted Bazel label.
 func (b *BazelModuleBase) HasHandcraftedLabel() bool {
 	return b.bazelProperties.Bazel_module.Label != nil
@@ -399,7 +421,15 @@
 	// prevents mixed builds from using auto-converted modules just by matching
 	// the package dir; it also has to have a bp2build mutator as well.
 	if ctx.Config().bp2buildModuleTypeConfig[ctx.OtherModuleType(module)] == false {
-		return false
+		if b, ok := module.(Bazelable); ok && b.BaseModuleType() != "" {
+			// For modules with custom types from soong_config_module_types,
+			// check that their _base module type_ has a bp2build mutator.
+			if ctx.Config().bp2buildModuleTypeConfig[b.BaseModuleType()] == false {
+				return false
+			}
+		} else {
+			return false
+		}
 	}
 
 	packagePath := ctx.OtherModuleDir(module)