linux/Documentation/sound
Oswald Buddenhagen bcdbd3b788 ALSA: emu10k1: enable bit-exact playback, part 2: voice attenuation
The voice volume is a raw fractional multiplier that can't actually
represent 1.0. To still enable real pass-through, we now set the volume
to 0.5 (which results in no loss of precision, as the FX bus provides
fractional values) and scale up the samples in DSP code.

To maintain backwards compatibility with existing configuration files,
we rescale the values in the mixer controls. The range is extended
upwards from 0xffff to 0x1fffd, which actually introduces the
possibility of specifying an amplification.

There is still a minor incompatibility with user space, namely if
someone loaded custom DSP code. They'll just get half the volume, so
this doesn't seem like a big deal.

Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Link: https://lore.kernel.org/r/20230514170323.3408834-8-oswald.buddenhagen@gmx.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2023-05-16 11:11:04 +02:00
..
cards ALSA: emu10k1: enable bit-exact playback, part 2: voice attenuation 2023-05-16 11:11:04 +02:00
designs Documentation: sound: correct spelling 2023-01-29 09:23:45 +01:00
hd-audio Merge branch 'for-linus' into for-next 2023-04-27 14:21:18 +02:00
kernel-api ALSA: docs: Fix code block indentation in ALSA driver example 2023-05-03 08:08:25 +02:00
soc ASoC: Merge up fixes 2022-07-11 15:51:01 +01:00
alsa-configuration.rst ALSA: docs: Extend module parameters description 2023-05-03 08:06:37 +02:00
index.rst Docs/sound/index: Add missing SPDX License Identifier 2023-01-24 15:28:52 -07:00