[src/trunk]: src/sys/dev/pci/hdaudio ossaudio's SNDCTL_DSP_GETOSPACE will cal...

[jmcneill <jmcneill%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e7b4584fb28b
branches:  trunk
changeset: 770575:e7b4584fb28b
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Mon Oct 24 02:08:22 2011 +0000

description:
ossaudio's SNDCTL_DSP_GETOSPACE will call AUDIO_SETINFO if the block size
isn't a power of two, and since the block size is changing this tells
audio(4) to halt output, reconfigure the device, then trigger output again.

mplayer's oss driver uses SNDCTL_DSP_GETOSPACE a lot.

Instead of simply rounding to 128 bytes as required by the hardware, change
hdafg_round_blocksize to return one of 128, 256, 512, 1024, 2048, 4096,
or 8192.

diffstat:

 sys/dev/pci/hdaudio/hdafg.c |  25 +++++++++++++++----------
 1 files changed, 15 insertions(+), 10 deletions(-)

diffs (59 lines):

diff -r 1bc0fea75802 -r e7b4584fb28b sys/dev/pci/hdaudio/hdafg.c
--- a/sys/dev/pci/hdaudio/hdafg.c       Sun Oct 23 23:41:56 2011 +0000
+++ b/sys/dev/pci/hdaudio/hdafg.c       Mon Oct 24 02:08:22 2011 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: hdafg.c,v 1.8 2011/09/07 20:34:58 jmcneill Exp $ */
+/* $NetBSD: hdafg.c,v 1.9 2011/10/24 02:08:22 jmcneill Exp $ */
 
 /*
  * Copyright (c) 2009 Precedence Technologies Ltd <support%precedence.co.uk@localhost>
@@ -60,7 +60,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: hdafg.c,v 1.8 2011/09/07 20:34:58 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: hdafg.c,v 1.9 2011/10/24 02:08:22 jmcneill Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -3801,7 +3801,7 @@
 {
        struct hdaudio_audiodev *ad = opaque;
        struct hdaudio_stream *st;
-       int bufsize;
+       int bufsize, nblksize;
 
        st = (mode == AUMODE_PLAY) ? ad->ad_playback : ad->ad_capture;
        if (st == NULL) {
@@ -3810,19 +3810,24 @@
                return 128;
        }
 
-       /* Multiple of 128 */
-       blksize &= ~127;
-       if (blksize <= 0)
+       if (blksize > 8192)
+               blksize = 8192;
+       else if (blksize < 0)
                blksize = 128;
 
+       /* HD audio wants a multiple of 128, and OSS wants a power of 2 */
+       for (nblksize = 128; nblksize < blksize; nblksize <<= 1)
+               ;
+
+       /* Make sure there are enough BDL descriptors */
        bufsize = st->st_data.dma_size;
-       if (bufsize > HDAUDIO_BDL_MAX * blksize) {
+       if (bufsize > HDAUDIO_BDL_MAX * nblksize) {
                blksize = bufsize / HDAUDIO_BDL_MAX;
-               if (blksize & 127)
-                       blksize = (blksize + 127) & ~127;
+               for (nblksize = 128; nblksize < blksize; nblksize <<= 1)
+                       ;
        }
 
-       return blksize;
+       return nblksize;
 }
 
 static int