[command]
DESCRIPTION
alsaucm (ALSA Use Case Manager) is a program to use the ALSA Use Case
Interface from the command line.
On complex sound cards, setting up audio routes is not trivial and
mixer settings can conflict one another preventing the audio card to
work at all.
The ALSA Use Case Manager is a mechanism for controlling complex audio
hardware establishing a relationship between hardware configurations
and meaningful use cases that the end-user can relate with.
The use case manager can also be used to switch between use cases when
necessary, in a consistent way.
At a lower level, the use case manager works by configuring the sound
card ALSA kcontrols to change the hardware digital and analog audio
routing to match the requested device use case.
The use case manager kcontrol configurations are stored in easy to mod‐
ify text files. An audio use case can be defined by a verb and device
parameter.
The verb describes the use case action i.e. a phone call, listening to
music, recording a conversation etc. The device describes the physical
audio capture and playback hardware i.e. headphones, phone handset,
bluetooth headset, etc.
OPTIONS
Available options:
-h, help
this help
-c, card NAME
open card NAME
-i, interactive
interactive mode
-b, batch FILE
batch mode (use '-' for the stdin input)
-n, no-open
do not open first card found
Available commands:
open NAME
open card NAME.
valid names are sound card names as listed in
/usr/share/alsa/ucm.
reset reset sound card to default state.
reload reload configuration.
listcards
list available cards.
list IDENTIFIER
list command, for items returning two entries (value+com‐
ment).
the value of the IDENTIFIER argument can can be:
· verbs - get verb list (in pair verb+comment)
· devices[/{verb}] - get list of supported devices (in pair
device+comment)
· modifiers[/{verb}] - get list of supported modifiers (in
pair modifier+comment)
The forms without the trailing /{verb} are valid only after a
specific verb has been set.
list1 IDENTIFIER
list command, for lists returning one item per entry.
the value of the IDENTIFIER argument can vary depending on
the context, it can be:
· TQ[/{verb}] - get list of Tone Quality identifiers
· enadevs - get list of enabled devices
· enamods - get list of enabled modifiers
· supporteddevs/{modifier}|{device}[/{verb}] - list of sup‐
ported devices
· conflictingdevs/{modifier}|{device}[/{verb}] - list of
conflicting devices
get IDENTIFIER
get string value.
the value of the IDENTIFIER argument can can be:
· verb - return current verb
· [=]{NAME}[/[{modifier}|{/device}][/{verb}]] (For valid
NAMEs look at the ALSA Use Case Interface)
geti IDENTIFIER
get integer value.
the value of the IDENTIFIER argument can can be:
· devstatus/{device}
· modtstaus/{device}
set IDENTIFIER VALUE
set string value
The value of the IDENTIFIER argument can can be:
· verb - set the verb to VALUE
· enadev - enable the device specified by VALUE
· disdev - disable the device specified by VALUE
· swdev/{olddevice} - switche device:
· disable olddevice and then enable the device specified
by VALUE
· if no device was enabled just return
· enamod - enable the modifier specified by VALUE
· dismod - disable the modifier specified by VALUE
· swmod/{oldmodifier} - switch modifier:
· disable oldmodifier and then enable the modifier speci‐
fied by VALUE
· if no modifier was enabled just return
Note that the identifiers referring to devices and modifiers
are valid only after setting a verb.
h, help
help
q, quit
quit
FILES
The master use case files for each supported sound card are in
/usr/share/alsa/ucm.
For example, the master use case file for the Pandaboard card is in
/usr/share/alsa/ucm/PandaBoard/PandaBoard.conf, this file lists all the
supported use cases, e.g.
SectionUseCase."HiFi" {
File "hifi"
Comment "Play HiFi quality Music."
}
...
Each use case defines a verb, which is described in the file specified
in the File directive, like above.
The HiFi verb above is described in /usr/share/alsa/ucm/Pand‐
aBoard/hifi.
For more details on the syntax of UCM files, see the alsa-lib source
code:
http://git.alsa-project.org/?p=alsa-lib.git;a=blob;f=src/ucm/parser.c
EXAMPLES OF USE
Some commands, like for instance list devices, can only work after
setting a verb in the same execution, for instance this sequence
doesn't work:
# alsaucm -c bytcr-rt5640 set verb HiFi
# alsaucm -c bytcr-rt5640 list devices
However this command does:
# alsaucm -n -b - < open bytcr-rt5640
set verb HiFi
list devices
EOM
An example of setting the Speaker device for the HiFi verb of the
bytcr-rt5640 card:
# alsaucm -n -b - < open bytcr-rt5640
reset
set verb HiFi
set enadev Speaker
EOM
SEE ALSO
· Use Case Interface:
http://www.alsa-project.org/alsa-doc/alsa-lib/groupucm.html
BUGS
None known.
AUTHOR
Antonio Ospite
COPYRIGHT
GPLv2+
2016-09-22 ALSAUCM(1)