ALSA: Kconfig: SND_AC97_POWER_SAVE description improvement

The description has been expanded to explain the time-out
value provided by the power_save module parameter.

Signed-off-by: Michael Witten <mfwitten@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Michael Witten 2010-07-14 23:54:21 +00:00 committed by Takashi Iwai
parent 992cbf7438
commit 1d8c1100fb

View File

@ -170,9 +170,25 @@ config SND_AC97_POWER_SAVE
AC97 codecs. In this mode, the power-mode is dynamically
controlled at each open/close.
The mode is activated by passing power_save=1 option to
snd-ac97-codec driver. You can toggle it dynamically over
sysfs, too.
The mode is activated by passing 'power_save=X' to the
snd-ac97-codec driver module, where 'X' is the time-out
value, a nonnegative integer that specifies how many
seconds of idle time the driver must count before it may
put the AC97 into power-save mode; a value of 0 (zero)
disables the use of this power-save mode.
After the snd-ac97-codec driver module has been loaded,
the 'power_save' parameter can be set via sysfs as follows:
echo 10 > /sys/module/snd_ac97_codec/parameters/power_save
In this case, the time-out is set to 10 seconds; setting
the time-out to 1 second (the minimum activation value)
isn't recommended because many applications try to reopen
the device frequently. A value of 10 seconds would be a
good choice for normal operations.
See Documentation/sound/alsa/powersave.txt for more details.
config SND_AC97_POWER_SAVE_DEFAULT
int "Default time-out for AC97 power-save mode"
@ -182,4 +198,6 @@ config SND_AC97_POWER_SAVE_DEFAULT
The default time-out value in seconds for AC97 automatic
power-save mode. 0 means to disable the power-save mode.
See SND_AC97_POWER_SAVE for more details.
endif # SND_DRIVERS