S1DREG_LCD_DISP_MODE
val = s1d13xxxfb_readreg(s1dfb, S1DREG_LCD_DISP_MODE); /* read colour control */
s1d13xxxfb_writereg(s1dfb, S1DREG_LCD_DISP_MODE, val);
display = s1d13xxxfb_readreg(par, S1DREG_LCD_DISP_MODE);