drm/mxsfb: Read bus flags from bridge if present

The bridge might have special requirmentes on the input bus. This
is e.g. used by the imx-nwl bridge.
Signed-off-by: Guido Günther <agx@sigxcpu.org>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1567078215-31601-3-git-send-email-robert.chiras@nxp.com

drivers/gpu/drm/mxsfb/mxsfb_crtc.c

@@ -209,7 +209,7 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
 {
 	struct drm_device *drm = mxsfb->pipe.crtc.dev;
 	struct drm_display_mode *m = &mxsfb->pipe.crtc.state->adjusted_mode;
-	const u32 bus_flags = mxsfb->connector->display_info.bus_flags;
+	u32 bus_flags = mxsfb->connector->display_info.bus_flags;
 	u32 vdctrl0, vsync_pulse_len, hsync_pulse_len;
 	int err;
 
@@ -233,6 +233,9 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
 
 	clk_set_rate(mxsfb->clk, m->crtc_clock * 1000);
 
+	if (mxsfb->bridge && mxsfb->bridge->timings)
+		bus_flags = mxsfb->bridge->timings->input_bus_flags;
+
 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Pixel clock: %dkHz (actual: %dkHz)\n",
 			     m->crtc_clock,
 			     (int)(clk_get_rate(mxsfb->clk) / 1000));