On Sun, 30 Mar 2025, Christos Margiolis wrote:
The branch main has been updated by christos:
URL:
https://cgit.FreeBSD.org/src/commit/?id=e1bbaa71d62c8681a576f9f5bedf475c7541bd35
commit e1bbaa71d62c8681a576f9f5bedf475c7541bd35
Author: Christos Margiolis <chris...@freebsd.org>
AuthorDate: 2025-03-30 17:45:38 +0000
Commit: Christos Margiolis <chris...@freebsd.org>
CommitDate: 2025-03-30 17:45:38 +0000
sound: Implement AFMT_FLOAT support
Even though the OSS manual [1] advises against using AFMT_FLOAT, there
are applications that expect the sound driver to support it, and might
not work properly without it.
This patch adds AFMT_F32_LE|BE (as well as AFMT_FLOAT for OSS
compatibility) in sys/soundcard.h and implements AFMT_F32_LE|BE <->
AFMT_S32_LE|BE conversion functions. As a result, applications can
write/read floats to/from sound(4), but internally, because sound(4)
works with integers, we convert floating point samples to integer ones,
before doing any processing.
The reason for encoding/decoding IEEE754s manually, instead of using
fpu_kern(9), is that fpu_kern(9) is not supported by all architectures,
and also introduces significant overhead.
The IEEE754 encoding/decoding implementation has been written by Ariff
Abdullah [2].
[1] http://manuals.opensound.com/developer/AFMT_FLOAT.html
[2] https://people.freebsd.org/~ariff/utils/ieee754.c
PR: 157050, 184380, 264973, 280612, 281390
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Reviewed by: emaste
Differential Revision: https://reviews.freebsd.org/D47638
---
sys/dev/sound/pcm/channel.c | 4 +++
sys/dev/sound/pcm/feeder_chain.c | 2 ++
sys/dev/sound/pcm/feeder_rate.c | 4 +++
sys/dev/sound/pcm/feeder_volume.c | 2 ++
sys/dev/sound/pcm/pcm.h | 67 +++++++++++++++++++++++++++++++++++++--
sys/dev/sound/pcm/sound.h | 13 +++++---
sys/sys/soundcard.h | 8 +++++
tests/sys/sound/pcm_read_write.c | 6 ++++
8 files changed, 98 insertions(+), 8 deletions(-)
diff --git a/sys/dev/sound/pcm/feeder_volume.c
b/sys/dev/sound/pcm/feeder_volume.c
index f72c6aa7ef4f..2d35bb56ef8f 100644
--- a/sys/dev/sound/pcm/feeder_volume.c
+++ b/sys/dev/sound/pcm/feeder_volume.c
@@ -93,6 +93,8 @@ FEEDVOLUME_DECLARE(U, 32, LE)
FEEDVOLUME_DECLARE(U, 16, BE)
FEEDVOLUME_DECLARE(U, 24, BE)
FEEDVOLUME_DECLARE(U, 32, BE)
+FEEDVOLUME_DECLARE(F, 32, LE)
+FEEDVOLUME_DECLARE(F, 32, BE)
#endif
struct feed_volume_info {
Could it be that they also need to be added to feed_volume_info_tab
below? Kernel LINT builds complain that they are unused.
/bz
--
Bjoern A. Zeeb r15:7
