TSI721_RIO_EM_INT_ENABLE
iowrite32(0, priv->regs + TSI721_RIO_EM_INT_ENABLE);
rval = ioread32(priv->regs + TSI721_RIO_EM_INT_ENABLE);
iowrite32(rval, priv->regs + TSI721_RIO_EM_INT_ENABLE);