if (vc4_hdmi->disable_4kp60) {
                struct drm_device *drm = connector->dev;
-               struct drm_display_mode *mode;
+               const struct drm_display_mode *mode;
 
                list_for_each_entry(mode, &connector->probed_modes, head) {
                        if (vc4_hdmi_mode_needs_scrambling(mode, 8, VC4_HDMI_OUTPUT_RGB)) {
 }
 
 static bool vc4_hdmi_supports_scrambling(struct drm_encoder *encoder,
-                                        struct drm_display_mode *mode)
+                                        const struct drm_display_mode *mode)
 {
        struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
        struct drm_display_info *display = &vc4_hdmi->connector.display_info;
 {
        struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
        struct drm_device *drm = vc4_hdmi->connector.dev;
-       struct drm_display_mode *mode = &vc4_hdmi->saved_adjusted_mode;
+       const struct drm_display_mode *mode = &vc4_hdmi->saved_adjusted_mode;
        unsigned long flags;
        int idx;
 
 
 static void vc4_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi,
                                 struct drm_connector_state *state,
-                                struct drm_display_mode *mode)
+                                const struct drm_display_mode *mode)
 {
        struct drm_device *drm = vc4_hdmi->connector.dev;
        bool hsync_pos = mode->flags & DRM_MODE_FLAG_PHSYNC;
 
 static void vc5_hdmi_set_timings(struct vc4_hdmi *vc4_hdmi,
                                 struct drm_connector_state *state,
-                                struct drm_display_mode *mode)
+                                const struct drm_display_mode *mode)
 {
        struct drm_device *drm = vc4_hdmi->connector.dev;
        const struct vc4_hdmi_connector_state *vc4_state =
                drm_atomic_get_new_connector_state(state, connector);
        struct vc4_hdmi_connector_state *vc4_conn_state =
                conn_state_to_vc4_hdmi_conn_state(conn_state);
-       struct drm_display_mode *mode = &vc4_hdmi->saved_adjusted_mode;
+       const struct drm_display_mode *mode = &vc4_hdmi->saved_adjusted_mode;
        unsigned long tmds_char_rate = vc4_conn_state->tmds_char_rate;
        unsigned long bvb_rate, hsm_rate;
        unsigned long flags;
        struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
        struct drm_device *drm = vc4_hdmi->connector.dev;
        struct drm_connector *connector = &vc4_hdmi->connector;
-       struct drm_display_mode *mode = &vc4_hdmi->saved_adjusted_mode;
+       const struct drm_display_mode *mode = &vc4_hdmi->saved_adjusted_mode;
        struct drm_connector_state *conn_state =
                drm_atomic_get_new_connector_state(state, connector);
        unsigned long flags;
 {
        struct vc4_hdmi *vc4_hdmi = encoder_to_vc4_hdmi(encoder);
        struct drm_device *drm = vc4_hdmi->connector.dev;
-       struct drm_display_mode *mode = &vc4_hdmi->saved_adjusted_mode;
+       const struct drm_display_mode *mode = &vc4_hdmi->saved_adjusted_mode;
        struct drm_display_info *display = &vc4_hdmi->connector.display_info;
        bool hsync_pos = mode->flags & DRM_MODE_FLAG_PHSYNC;
        bool vsync_pos = mode->flags & DRM_MODE_FLAG_PVSYNC;