diff --git a/mlir/include/mlir/Transforms/DialectConversion.h b/mlir/include/mlir/Transforms/DialectConversion.h
--- a/mlir/include/mlir/Transforms/DialectConversion.h
+++ b/mlir/include/mlir/Transforms/DialectConversion.h
@@ -607,6 +607,12 @@
     if (callback)
       setLegalityCallback(dialectNames, *callback);
   }
+  template <typename... Args>
+  void addDynamicallyLegalDialect(DynamicLegalityCallbackFn callback) {
+    SmallVector<StringRef, 2> dialectNames({Args::getDialectNamespace()...});
+    setDialectAction(dialectNames, LegalizationAction::Dynamic);
+    setLegalityCallback(dialectNames, callback);
+  }
 
   /// Register unknown operations as dynamically legal. For operations(and
   /// dialects) that do not have a set legalization action, treat them as
diff --git a/mlir/lib/Dialect/SPIRV/SPIRVLowering.cpp b/mlir/lib/Dialect/SPIRV/SPIRVLowering.cpp
--- a/mlir/lib/Dialect/SPIRV/SPIRVLowering.cpp
+++ b/mlir/lib/Dialect/SPIRV/SPIRVLowering.cpp
@@ -657,10 +657,9 @@
       new SPIRVConversionTarget(targetAttr));
   SPIRVConversionTarget *targetPtr = target.get();
   target->addDynamicallyLegalDialect<SPIRVDialect>(
-      Optional<ConversionTarget::DynamicLegalityCallbackFn>(
-          // We need to capture the raw pointer here because it is stable:
-          // target will be destroyed once this function is returned.
-          [targetPtr](Operation *op) { return targetPtr->isLegalOp(op); }));
+      // We need to capture the raw pointer here because it is stable:
+      // target will be destroyed once this function is returned.
+      [targetPtr](Operation *op) { return targetPtr->isLegalOp(op); });
   return target;
 }
 
diff --git a/mlir/test/lib/Transforms/TestBufferPlacement.cpp b/mlir/test/lib/Transforms/TestBufferPlacement.cpp
--- a/mlir/test/lib/Transforms/TestBufferPlacement.cpp
+++ b/mlir/test/lib/Transforms/TestBufferPlacement.cpp
@@ -127,9 +127,7 @@
     auto isLegalOperation = [&](Operation *op) {
       return converter.isLegal(op);
     };
-    target.addDynamicallyLegalDialect<linalg::LinalgDialect>(
-        Optional<ConversionTarget::DynamicLegalityCallbackFn>(
-            isLegalOperation));
+    target.addDynamicallyLegalDialect<linalg::LinalgDialect>(isLegalOperation);
 
     // Mark Standard Return operations illegal as long as one operand is tensor.
     target.addDynamicallyLegalOp<mlir::ReturnOp>([&](mlir::ReturnOp returnOp) {