diff --git a/dlls/wined3d/device.c b/dlls/wined3d/device.c
index ed438102a9b..2916b2d2b4c 100644
--- a/dlls/wined3d/device.c
+++ b/dlls/wined3d/device.c
@@ -3213,7 +3213,7 @@ HRESULT CDECL wined3d_device_set_ps_consts_f(struct wined3d_device *device,
     return WINED3D_OK;
 }
 
-HRESULT CDECL wined3d_device_get_ps_consts_f(struct wined3d_device *device,
+HRESULT CDECL wined3d_device_get_ps_consts_f(const struct wined3d_device *device,
         UINT start_register, float *constants, UINT vector4f_count)
 {
     int count = min(vector4f_count, device->d3d_pshader_constantF - start_register);
diff --git a/include/wine/wined3d.h b/include/wine/wined3d.h
index 6c31e141796..85f47b4c852 100644
--- a/include/wine/wined3d.h
+++ b/include/wine/wined3d.h
@@ -2233,7 +2233,7 @@ struct wined3d_shader * __cdecl wined3d_device_get_pixel_shader(const struct win
 void __cdecl wined3d_device_get_primitive_type(struct wined3d_device *device, WINED3DPRIMITIVETYPE *primitive_topology);
 HRESULT __cdecl wined3d_device_get_ps_consts_b(const struct wined3d_device *device,
         UINT start_register, BOOL *constants, UINT bool_count);
-HRESULT __cdecl wined3d_device_get_ps_consts_f(struct wined3d_device *device,
+HRESULT __cdecl wined3d_device_get_ps_consts_f(const struct wined3d_device *device,
         UINT start_register, float *constants, UINT vector4f_count);
 HRESULT __cdecl wined3d_device_get_ps_consts_i(const struct wined3d_device *device,
         UINT start_register, int *constants, UINT vector4i_count);