From: Matthias Rampke <matthias@rampke.de>
Date: Sat, 7 May 2011 22:18:41 +0000 (+0200)
Subject: sound/pcm: fix calculation of PCM channel timeout
X-Git-Url: http://gitweb.dragonflybsd.org/~matthiasr/dragonfly.git/commitdiff_plain/4d3f6d0ed3435

sound/pcm: fix calculation of PCM channel timeout

this fixes a "pcm0:virtual:0:dsp0.2: play interrupt timeout, channel dead" error
and sound dying after a few seconds of playback.
I encountered on my Thinkpad X40. It was discussed on freebsd-current in 2004[1] but that code is no longer present in FBSD while we still have it.

The patch removes a line fixing a channel timeout to 1 tick instead of the value calculated immediately beforehand, thus restoring the calculation.

[1] http://lists.freebsd.org/pipermail/freebsd-current/2004-September/036805.html
---

diff --git a/sys/dev/sound/pcm/channel.c b/sys/dev/sound/pcm/channel.c
index 45f5d8f..cecf972 100644
--- a/sys/dev/sound/pcm/channel.c
+++ b/sys/dev/sound/pcm/channel.c
@@ -340,7 +340,7 @@ chn_write(struct pcm_channel *c, struct uio *buf, int ioflags)
 				timeout = (hz * sndbuf_getblksz(bs)) / (sndbuf_getspd(bs) * sndbuf_getbps(bs));
 				if (timeout < 1)
 					timeout = 1;
-				timeout = 1;
+				/* timeout = 1; */
 	   			ret = chn_sleep(c, "pcmwr", timeout);
 				if (ret == EWOULDBLOCK) {
 					count -= timeout;