* @colour_fg: Foreground colour (pixel value)
* @colour_bg: Background colour (pixel value)
* @flush_dcache: true to enable flushing of the data cache after
* the LCD is updated
* @cmap: Colour map for 8-bit-per-pixel displays
* @colour_fg: Foreground colour (pixel value)
* @colour_bg: Background colour (pixel value)
* @flush_dcache: true to enable flushing of the data cache after
* the LCD is updated
* @cmap: Colour map for 8-bit-per-pixel displays