diff --git a/drivers/tty/serial/wch_35x/wch_common.h b/drivers/tty/serial/wch_35x/wch_common.h
index 4de18085..9c1fc103 100644
--- a/drivers/tty/serial/wch_35x/wch_common.h
+++ b/drivers/tty/serial/wch_35x/wch_common.h
@@ -30,6 +30,7 @@
 #include <linux/ptrace.h>
 #include <linux/sched.h>
 #include <linux/serial_core.h>
+#include <linux/semaphore.h>
 #include <linux/string.h>
 #include <linux/timer.h>
 
diff --git a/drivers/tty/serial/wch_35x/wch_serial.c b/drivers/tty/serial/wch_35x/wch_serial.c
index 45a17404..44721695 100644
--- a/drivers/tty/serial/wch_35x/wch_serial.c
+++ b/drivers/tty/serial/wch_35x/wch_serial.c
@@ -11,11 +11,17 @@
  * more details.
  */
 
+#include <nvidia/conftest.h>
+
 #include <linux/version.h>
 
 #include "wch_common.h"
 
+#if defined(NV_DEFINE_SEMAPHORE_HAS_NUMBER_ARG)
+static DEFINE_SEMAPHORE(ser_port_sem, 1);
+#else
 static DEFINE_SEMAPHORE(ser_port_sem);
+#endif
 
 #define WCH_HIGH_BITS_OFFSET ((sizeof(long) - sizeof(int)) * 8)
 #define wch_ser_users(state) ((state)->count + ((state)->info ? (state)->info->blocked_open : 0))
diff --git a/scripts/conftest/Makefile b/scripts/conftest/Makefile
index aa29dfa2..6c503579 100644
--- a/scripts/conftest/Makefile
+++ b/scripts/conftest/Makefile
@@ -90,6 +90,7 @@ endef
 
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += bus_type_struct_remove_has_int_return_type
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += class_struct_devnode_has_const_dev_arg
+NV_CONFTEST_FUNCTION_COMPILE_TESTS += define_semaphore_has_number_arg
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += devm_thermal_of_zone_register
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += drm_aperture_remove_framebuffers_has_drm_driver_arg
 NV_CONFTEST_FUNCTION_COMPILE_TESTS += drm_driver_struct_has_irq_enabled_arg
diff --git a/scripts/conftest/conftest.sh b/scripts/conftest/conftest.sh
index 48904402..a229fb7c 100755
--- a/scripts/conftest/conftest.sh
+++ b/scripts/conftest/conftest.sh
@@ -6332,6 +6332,22 @@ compile_test() {
             compile_check_conftest "$CODE" "NV_CLASS_STRUCT_DEVNODE_HAS_CONST_DEV_ARG" "" "types"
         ;;
 
+        define_semaphore_has_number_arg)
+            #
+            # Determine if the macro DEFINE_SEMAPHORE has a number argument.
+            #
+            # In Linux v6.4, 48380368dec1 ("Change DEFINE_SEMAPHORE() to
+            # take a number argument") updated the macro DEFINE_SEMAPHORE to
+            # take a number argument.
+            #
+            CODE="
+            #include <linux/semaphore.h>
+
+            DEFINE_SEMAPHORE(my_sem, 1);"
+
+            compile_check_conftest "$CODE" "NV_DEFINE_SEMAPHORE_HAS_NUMBER_ARG" "" "types"
+        ;;
+
         devm_thermal_of_zone_register)
             #
             # Determine whether devm_thermal_of_zone_register is present.