struct drm_device *dev = crtc->dev;
        struct fsl_dcu_drm_device *fsl_dev = dev->dev_private;
        struct drm_display_mode *mode = &crtc->state->mode;
-       unsigned int hbp, hfp, hsw, vbp, vfp, vsw, div, index;
+       unsigned int hbp, hfp, hsw, vbp, vfp, vsw, div, index, pol = 0;
        unsigned long dcuclk;
 
        index = drm_crtc_index(crtc);
        vfp = mode->vsync_start - mode->vdisplay;
        vsw = mode->vsync_end - mode->vsync_start;
 
+       if (mode->flags & DRM_MODE_FLAG_NHSYNC)
+               pol |= DCU_SYN_POL_INV_HS_LOW;
+
+       if (mode->flags & DRM_MODE_FLAG_NVSYNC)
+               pol |= DCU_SYN_POL_INV_VS_LOW;
+
        regmap_write(fsl_dev->regmap, DCU_HSYN_PARA,
                     DCU_HSYN_PARA_BP(hbp) |
                     DCU_HSYN_PARA_PW(hsw) |
                     DCU_DISP_SIZE_DELTA_Y(mode->vdisplay) |
                     DCU_DISP_SIZE_DELTA_X(mode->hdisplay));
        regmap_write(fsl_dev->regmap, DCU_DIV_RATIO, div);
-       regmap_write(fsl_dev->regmap, DCU_SYN_POL,
-                    DCU_SYN_POL_INV_VS_LOW | DCU_SYN_POL_INV_HS_LOW);
+       regmap_write(fsl_dev->regmap, DCU_SYN_POL, pol);
        regmap_write(fsl_dev->regmap, DCU_BGND, DCU_BGND_R(0) |
                     DCU_BGND_G(0) | DCU_BGND_B(0));
        regmap_write(fsl_dev->regmap, DCU_DCU_MODE,