SC16IS7XX_IOSTATE_REG
val = sc16is7xx_port_read(port, SC16IS7XX_IOSTATE_REG);
sc16is7xx_port_update(port, SC16IS7XX_IOSTATE_REG, BIT(offset),
u8 state = sc16is7xx_port_read(port, SC16IS7XX_IOSTATE_REG);
sc16is7xx_port_write(port, SC16IS7XX_IOSTATE_REG, state);
case SC16IS7XX_IOSTATE_REG: