diff --git a/dlls/wined3d/device.c b/dlls/wined3d/device.c
index e1cb38f5c45..4caac23fd9a 100644
--- a/dlls/wined3d/device.c
+++ b/dlls/wined3d/device.c
@@ -2722,7 +2722,7 @@ HRESULT CDECL wined3d_device_set_vs_consts_b(struct wined3d_device *device,
     return WINED3D_OK;
 }
 
-HRESULT CDECL wined3d_device_get_vs_consts_b(struct wined3d_device *device,
+HRESULT CDECL wined3d_device_get_vs_consts_b(const struct wined3d_device *device,
         UINT start_register, BOOL *constants, UINT bool_count)
 {
     UINT count = min(bool_count, MAX_CONST_B - start_register);
diff --git a/include/wine/wined3d.h b/include/wine/wined3d.h
index ed039297006..08b6462665d 100644
--- a/include/wine/wined3d.h
+++ b/include/wine/wined3d.h
@@ -2266,7 +2266,7 @@ HRESULT __cdecl wined3d_device_get_vertex_declaration(const struct wined3d_devic
         struct wined3d_vertex_declaration **declaration);
 struct wined3d_shader * __cdecl wined3d_device_get_vertex_shader(const struct wined3d_device *device);
 HRESULT __cdecl wined3d_device_get_viewport(const struct wined3d_device *device, WINED3DVIEWPORT *viewport);
-HRESULT __cdecl wined3d_device_get_vs_consts_b(struct wined3d_device *device,
+HRESULT __cdecl wined3d_device_get_vs_consts_b(const struct wined3d_device *device,
         UINT start_register, BOOL *constants, UINT bool_count);
 HRESULT __cdecl wined3d_device_get_vs_consts_f(struct wined3d_device *device,
         UINT start_register, float *constants, UINT vector4f_count);