diff --git a/libserialport_internal.h b/libserialport_internal.h
index ecf8fe9..f1d0d85 100644
--- a/libserialport_internal.h
+++ b/libserialport_internal.h
@@ -93,6 +93,9 @@
 #include <IOKit/serial/ioss.h>
 #include <sys/syslimits.h>
 #include <mach/mach_time.h>
+#if MAC_OS_X_VERSION_MAX_ALLOWED < 120000 /* Before macOS 12 */
+#define kIOMainPortDefault kIOMasterPortDefault
+#endif
 #endif
 #ifdef __linux__
 #include <dirent.h>
diff --git a/macosx.c b/macosx.c
index a0df84e..0d22bb6 100644
--- a/macosx.c
+++ b/macosx.c
@@ -42,7 +42,7 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
 	if (!(classes = IOServiceMatching(kIOSerialBSDServiceValue)))
 		RETURN_FAIL("IOServiceMatching() failed");
 
-	if (IOServiceGetMatchingServices(kIOMasterPortDefault, classes,
+	if (IOServiceGetMatchingServices(kIOMainPortDefault, classes,
 	                                 &iter) != KERN_SUCCESS)
 		RETURN_FAIL("IOServiceGetMatchingServices() failed");
 
@@ -210,7 +210,7 @@ SP_PRIV enum sp_return list_ports(struct sp_port ***list)
 	}
 
 	DEBUG("Getting matching services");
-	if (IOServiceGetMatchingServices(kIOMasterPortDefault, classes,
+	if (IOServiceGetMatchingServices(kIOMainPortDefault, classes,
 	                                 &iter) != KERN_SUCCESS) {
 		SET_FAIL(ret, "IOServiceGetMatchingServices() failed");
 		goto out_done;