allow low level audio drivers to specify a default sample format,

instead of 8-bit mono mulaw @ 8kHz.

this is just the infrastructure; no drivers are specifying a default
yet.

ok ratchov@, deanna@

2 files changed, 24 insertions, 7 deletions

diff --git a/share/man/man4/audio.4 b/share/man/man4/audio.4
index e14a6893489..0c54211e815 100644
--- a/share/man/man4/audio.4
+++ b/share/man/man4/audio.4
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: audio.4,v 1.51 2008/03/22 11:05:31 ratchov Exp $
+.\"	$OpenBSD: audio.4,v 1.52 2008/04/21 00:32:42 jakemsr Exp $
 .\"	$NetBSD: audio.4,v 1.20 1998/05/28 17:27:15 augustss Exp $
 .\"
 .\" Copyright (c) 1996 The NetBSD Foundation, Inc.
@@ -35,7 +35,7 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: March 22 2008 $
+.Dd $Mdocdate: April 21 2008 $
 .Dt AUDIO 4
 .Os
 .Sh NAME
@@ -87,14 +87,15 @@ device while it is in use.
 .Sh SAMPLING DEVICES
 When
 .Pa /dev/audio
-is opened, it automatically directs the underlying driver to manipulate
-monaural 8-bit mu-law samples.
+is opened, it automatically configures the underlying driver for the
+hardware's default sample format, or monaural 8-bit mu-law if a default
+sample format has not been specified by the underlying driver.
 In addition, if it is opened read-only
 (write-only) the device is set to half-duplex record (play) mode with
 recording (playing) unpaused and playing (recording) paused.
 When
 .Pa /dev/sound
-is opened, it maintains the previous audio sample mode and
+is opened, it maintains the previous audio sample format and
 record/playback mode.
 In all other respects
 .Pa /dev/audio
diff --git a/share/man/man9/audio.9 b/share/man/man9/audio.9
index d54a2e79558..0be2a30e59c 100644
--- a/share/man/man9/audio.9
+++ b/share/man/man9/audio.9
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: audio.9,v 1.17 2007/05/31 19:20:00 jmc Exp $
+.\"	$OpenBSD: audio.9,v 1.18 2008/04/21 00:32:42 jakemsr Exp $
 .\"	$NetBSD: audio.9,v 1.14 2000/02/11 22:56:15 kleink Exp $
 .\"
 .\" Copyright (c) 1999, 2000 The NetBSD Foundation, Inc.
@@ -35,7 +35,7 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: May 31 2007 $
+.Dd $Mdocdate: April 21 2008 $
 .Dt AUDIO 9
 .Os
 .Sh NAME
@@ -93,6 +93,7 @@ struct audio_hw_if {
 		    void (*)(void *), void *, struct audio_params *);
 	int	(*trigger_input)(void *, void *, void *, int,
 		    void (*)(void *), void *, struct audio_params *);
+	void	(*get_default_params)(void *, int, struct audio_params *);
 };
 
 struct audio_params {
@@ -469,6 +470,21 @@ will be called with the argument
 Once started, the transfer may be stopped using
 .Fn halt_input .
 This function returns 0 on success, otherwise an error code.
+.It Fn "void (*get_default_params)" "void *hdl" "int direction" \
+"struct audio_params *param"
+This function is optional.
+If supplied, it is called to retrieve the default configuration
+for the given
+.Fa direction ,
+parameterized in
+.Fa param .
+.Fa direction
+is
+.Dv AUMODE_PLAY
+or
+.Dv AUMODE_RECORD .
+The default configuration should not include emulated formats, and should
+reflect the optimal operating configuration for the underlying hardware.
 .El
 .Pp
 The