From 53927fa89c9213eb2c5e01bb305ebf0990a26c04 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Wed, 25 Jul 2001 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 2001-07-25

---
 port/devuart.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/port/devuart.c b/port/devuart.c
index 64abd0d5c4379f58ded4fad59ee6fd9d9ab29b23..31d04b67bff21775bae57335ae7ba2bb374c4756 100644
--- a/port/devuart.c
+++ b/port/devuart.c
@@ -623,8 +623,9 @@ uartclock(void)
 					(*p->phys->rts)(p, 0);
 				p->ir = p->istage;
 			}
-			if(qproduce(p->iq, p->ir, iw-p->ir) < 0)
-				(*p->phys->rts)(p, 0);
+			if(iw > p->ir)
+				if(qproduce(p->iq, p->ir, iw-p->ir) < 0)
+					(*p->phys->rts)(p, 0);
 			p->ir = iw;
 		}