551 	struct circ_buf *circ;  in uart_put_char()  local
555 	circ = &state->xmit;  in uart_put_char()
557 	if (!circ->buf) {  in uart_put_char()
562 	if (port && uart_circ_chars_free(circ) != 0) {  in uart_put_char()
563 		circ->buf[circ->head] = c;  in uart_put_char()
564 		circ->head = (circ->head + 1) & (UART_XMIT_SIZE - 1);  in uart_put_char()
581 	struct circ_buf *circ;  in uart_write()  local
595 	circ = &state->xmit;  in uart_write()
596 	if (!circ->buf) {  in uart_write()
602 		c = CIRC_SPACE_TO_END(circ->head, circ->tail, UART_XMIT_SIZE);  in uart_write()
607 		memcpy(circ->buf + circ->head, buf, c);  in uart_write()
608 		circ->head = (circ->head + c) & (UART_XMIT_SIZE - 1);  in uart_write()