SND_CARD_CREATE(9) Sound Devices SND_CARD_CREATE(9)NAME
snd_card_create - create and initialize a soundcard structure
SYNOPSIS
int snd_card_create(int idx, const char * xid, struct module * module, int extra_size, struct snd_card ** card_ret);
ARGUMENTS
idx
card index (address) [0 ... (SNDRV_CARDS-1)]
xid
card identification (ASCII string)
module
top level module for locking
extra_size
allocate this extra size after the main soundcard structure
card_ret
the pointer to store the created card instance
DESCRIPTION
Creates and initializes a soundcard structure.
The function allocates snd_card instance via kzalloc with the given space for the driver to use freely. The allocated struct is stored in
the given card_ret pointer.
Returns zero if successful or a negative error code.
COPYRIGHT Kernel Hackers Manual 2.6. July 2010 SND_CARD_CREATE(9)
Check Out this Related Man Page
AMIXER(1) General Commands Manual AMIXER(1)NAME
amixer - command-line mixer for ALSA soundcard driver
SYNOPSIS
amixer [-option] [cmd]
DESCRIPTION
amixer allows command-line control of the mixer for the ALSA soundcard driver. amixer supports multiple soundcards.
amixer with no arguments will display the current mixer settings for the default soundcard and device. This is a good way to see a list of
the simple mixer controls you can use.
COMMANDS
help Shows syntax.
info Shows the information about a mixer device.
scontrols
Shows a complete list of simple mixer controls.
scontents
Shows a complete list of simple mixer controls with their contents.
set or sset <SCONTROL> <PARAMETER> ...
Sets the simple mixer control contents. The parameter can be the volume either as a percentage from 0% to 100% with % suffix, a dB
gain with dB suffix (like -12.5dB), or an exact hardware value. The dB gain can be used only for the mixer elements with available
dB information. When plus(+) or minus(-) letter is appended after volume value, the volume is incremented or decremented from the
current value, respectively.
The parameters cap, nocap, mute, unmute, toggle are used to change capture (recording) and muting for the group specified.
The optional modifiers can be put as extra parameters to specify the stream direction or channels to apply. The modifiers playback
and capture specify the stream, and the modifiers front, rear, center, woofer are used to specify channels to be changed.
A simple mixer control must be specified. Only one device can be controlled at a time.
get or sget <SCONTROL>
Shows the simple mixer control contents.
A simple mixer control must be specified. Only one device can be controlled at a time.
controls
Shows a complete list of card controls.
contents
Shows a complete list of card controls with their contents.
cset <CONTROL> <PARAMETER> ...
Sets the card control contents. The identifier has these components: iface, name, index, device, subdevice, numid. The next argument
specifies the value of control.
cget <CONTROL>
Shows the card control contents. The identifier has same syntax as for the cset command.
OPTIONS -c card
Select the card number to control. The device name created from this parameter has syntax 'hw:N' where N is specified card number.
-D device
Select the device name to control. The default control name is 'default'.
-s | --stdin
Read from stdin and execute the command on each line sequentially. When this option is given, the command in command-line arguments
is ignored.
Only sset and cset are accepted. Other commands are ignored. The commands to unmatched ids are ignored without errors too.
-h Help: show syntax.
-q Quiet mode. Do not show results of changes.
EXAMPLES
amixer -c 1 sset Line,0 80%,40% unmute cap
will set the second soundcard's left line input volume to 80% and right line input to 40%, unmute it, and select it as a source for
capture (recording).
amixer -c 1 -- sset Master playback -20dB
will set the master volume of the second card to -20dB. If the master has multiple channels, all channels are set to the same
value.
amixer -c 1 set PCM 2dB+
will increase the PCM volume of the second card with 2dB. When both playback and capture volumes exist, this is applied to both
volumes.
amixer -c 2 cset iface=MIXER,name='Line Playback Volume",index=1 40%
will set the third soundcard's second line playback volume(s) to 40%
amixer -c 2 cset numid=34 40%
will set the 34th soundcard element to 40%
BUGS
None known.
AUTHOR
amixer is by Jaroslav Kysela <perex@perex.cz>. This document is by Paul Winkler <zarmzarm@erols.com> and Jaroslav Kysela <perex@perex.cz>.
11 Aug 2000 AMIXER(1)