AT91_TWI_FMR
fifo_mr = at91_twi_read(dev, AT91_TWI_FMR);
at91_twi_write(dev, AT91_TWI_FMR, fifo_mr);
fifo_mr = at91_twi_read(dev, AT91_TWI_FMR);
at91_twi_write(dev, AT91_TWI_FMR, fifo_mr);
unsigned fifo_mr = at91_twi_read(dev, AT91_TWI_FMR);
at91_twi_write(dev, AT91_TWI_FMR, fifo_mr);