Diffstat (limited to 'sound/drivers')
1 files changed, 22 insertions, 4 deletions
diff --git a/sound/drivers/Kconfig b/sound/drivers/Kconfig
index b6ae7628525..c8961165277 100644
@@ -174,7 +174,7 @@ config SND_ML403_AC97CR
Say Y here to include support for the
- opb_ac97_controller_ref_v1_00_a ip core found in Xilinx' ML403
+ opb_ac97_controller_ref_v1_00_a ip core found in Xilinx's ML403
To compile this driver as a module, choose M here: the module
@@ -189,9 +189,25 @@ 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.
int "Default time-out for AC97 power-save mode"
@@ -201,4 +217,6 @@ 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