Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Off-by-one error in limiting the DMAC buffer size for Audio 2 to 64K (actually

Browse Source 
64K - 1); from Dave Sainty in PR kern/9064.
This commit is contained in:
kleink 1999-12-28 19:26:26 +00:00
parent 73479d22b8
commit 1e9bb239a3
1 changed files with 15 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
sys/dev/pci/eso.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: eso.c,v 1.15 1999/12/28 01:39:38 kleink Exp $ */
/* $NetBSD: eso.c,v 1.16 1999/12/28 19:26:26 kleink Exp $ */
/*
* Copyright (c) 1999 Klaus J. Klein
@ -1577,10 +1577,21 @@ eso_round_buffersize(hdl, direction, bufsize)
int direction;
size_t bufsize;
{
size_t maxsize;
/* 64K restriction: ISA at eleven? */
if (bufsize > 65536)
bufsize = 65536;
/*
* The playback DMA buffer size on the Solo-1 is limited to 2^16 -
* 1 bytes. This is because A2DMAC is a two byte value indicating
* the literal byte count, and zero does not appear to be used as
* a special case for 2^16.
*
* For recording, DMAC_DMAC is the byte count - 1, so 2^16 can be
* represented.
*/
maxsize = (direction == AUMODE_PLAY) ? 65535 : 65536;
if (bufsize > maxsize)
bufsize = maxsize;
return (bufsize);
}