diff --git a/Package.swift b/Package.swift
index 0931529c5..5ce8a2b29 100644
--- a/Package.swift
+++ b/Package.swift
@@ -48,7 +48,7 @@ let packageDependencies: [Package.Dependency] = [
   ),
   .package(
     url: "https://github.com/apple/swift-protobuf.git",
-    from: "1.20.1"
+    from: "1.20.2"
   ),
   .package(
     url: "https://github.com/apple/swift-log.git",
diff --git a/Package@swift-5.5.swift b/Package@swift-5.5.swift
index a6806791f..116070a64 100644
--- a/Package@swift-5.5.swift
+++ b/Package@swift-5.5.swift
@@ -49,7 +49,7 @@ let packageDependencies: [Package.Dependency] = [
   .package(
     name: "SwiftProtobuf",
     url: "https://github.com/apple/swift-protobuf.git",
-    from: "1.19.0"
+    from: "1.20.2"
   ),
   .package(
     url: "https://github.com/apple/swift-log.git",
diff --git a/Sources/protoc-gen-grpc-swift/StreamingType.swift b/Sources/protoc-gen-grpc-swift/StreamingType.swift
index c6f108d3f..bb22f4464 100644
--- a/Sources/protoc-gen-grpc-swift/StreamingType.swift
+++ b/Sources/protoc-gen-grpc-swift/StreamingType.swift
@@ -38,14 +38,14 @@ extension StreamingType {
 }
 
 internal func streamingType(_ method: MethodDescriptor) -> StreamingType {
-  if method.proto.clientStreaming {
-    if method.proto.serverStreaming {
+  if method.clientStreaming {
+    if method.serverStreaming {
       return .bidirectionalStreaming
     } else {
       return .clientStreaming
     }
   } else {
-    if method.proto.serverStreaming {
+    if method.serverStreaming {
       return .serverStreaming
     } else {
       return .unary
diff --git a/Sources/protoc-gen-grpc-swift/main.swift b/Sources/protoc-gen-grpc-swift/main.swift
index 76387fba2..091428a97 100644
--- a/Sources/protoc-gen-grpc-swift/main.swift
+++ b/Sources/protoc-gen-grpc-swift/main.swift
@@ -125,8 +125,8 @@ func main() throws {
 
   // Only generate output for services.
   for name in request.fileToGenerate {
-    let fileDescriptor = descriptorSet.lookupFileDescriptor(protoName: name)
-    if !fileDescriptor.services.isEmpty {
+    if let fileDescriptor = descriptorSet.fileDescriptor(named: name),
+       !fileDescriptor.services.isEmpty {
       let grpcFileName = uniqueOutputFileName(
         component: "grpc",
         fileDescriptor: fileDescriptor,