Look for scalafmt config also in the root project

README.md

@@ -14,7 +14,10 @@ Usage
 	}
 
 	scalafmt {
-	    // configFilePath = ".scalafmt.conf" // .scalafmt.conf in the project root is default value, provide only if other location is needed
+	    // .scalafmt.conf in the project root is default value, provide only if other location is needed
+	    // config file has to be relative path from current project or root project in case of multimodule projects
+	    // example usage: 
+	    // configFilePath = ".scalafmt.conf"
 	}
 
 

src/main/groovy/cz/alenkacz/gradle/scalafmt/ConfigFactory.groovy

@@ -10,8 +10,12 @@ class ConfigFactory {
     static ScalafmtConfig load(Logger logger, Project project, String configFilePath) {
         def customConfig = project.file(configFilePath)
         if (!customConfig.exists()) {
-            logger.info("Custom config $configFilePath not found, using default scalafmt config")
-            return ScalafmtConfig$.MODULE$.default
+            // when config does not exist in the project folder, look also to a root of multimodule project
+            customConfig = project.rootProject.file(configFilePath)
+            if (!customConfig.exists()) {
+                logger.info("Custom config $configFilePath not found, using default scalafmt config")
+                return ScalafmtConfig$.MODULE$.default
+            }
         }
         def parsedConfig = Config.fromHoconString(customConfig.text, Config.fromHoconString$default$2())