serial8250_fifo_wait_for_lsr_thre
void serial8250_fifo_wait_for_lsr_thre(struct uart_8250_port *up, unsigned int count);
serial8250_fifo_wait_for_lsr_thre(up, p->fifosize);
EXPORT_SYMBOL_NS_GPL(serial8250_fifo_wait_for_lsr_thre, "SERIAL_8250");
serial8250_fifo_wait_for_lsr_thre(up, fifosize);
serial8250_fifo_wait_for_lsr_thre(up, tx_count);