# SPDX-License-Identifier: GPL-2.0-only
# ALSA soundcard-configuration
config SND_TIMER
tristate
config SND_PCM
tristate
select SND_TIMER if SND_PCM_TIMER
config SND_PCM_ELD
bool
config SND_PCM_IEC958
bool
config SND_DMAENGINE_PCM
tristate
config SND_HWDEP
tristate
config SND_SEQ_DEVICE
tristate
config SND_RAWMIDI
tristate
select SND_SEQ_DEVICE if SND_SEQUENCER != n
config SND_UMP
tristate
select SND_RAWMIDI
config SND_UMP_LEGACY_RAWMIDI
bool "Legacy raw MIDI support for UMP streams"
depends on SND_UMP
help
This option enables the legacy raw MIDI support for UMP streams.
When this option is set, an additional rawmidi device for the
legacy MIDI 1.0 byte streams is created for each UMP Endpoint.
The device contains 16 substreams corresponding to UMP groups.
config SND_CORE_TEST
tristate "Sound core KUnit test"
depends on KUNIT
select SND_PCM
default KUNIT_ALL_TESTS
help
This options enables the sound core functions KUnit test.
KUnit tests run during boot and output the results to the debug
log in TAP format (https://testanything.org/). Only useful for
kernel devs running KUnit test harness and are not for inclusion
into a production build.
For more information on KUnit and unit tests in general, refer
to the KUnit documentation in Documentation/dev-tools/kunit/.
config SND_COMPRESS_OFFLOAD
tristate
config SND_JACK
bool
# enable input device support in jack layer
config SND_JACK_INPUT_DEV
bool
depends on SND_JACK
default y if INPUT=y || INPUT=SND
config SND_OSSEMUL
bool "Enable OSS Emulation"
select SOUND_OSS_CORE
help
This option enables the build of OSS emulation layer.
config SND_MIXER_OSS
tristate "OSS Mixer API"
depends on SND_OSSEMUL
help
To enable OSS mixer API emulation (/dev/mixer*), say Y here
and read <file:Documentation/sound/designs/oss-emulation.rst>.
Many programs still use the OSS API, so say Y.
To compile this driver as a module, choose M here: the module
will be called snd-mixer-oss.
config SND_PCM_OSS
tristate "OSS PCM (digital audio) API"
depends on SND_OSSEMUL
select SND_PCM
help
To enable OSS digital audio (PCM) emulation (/dev/dsp*), say Y
here and read <file:Documentation/sound/designs/oss-emulation.rst>.
Many programs still use the OSS API, so say Y.
To compile this driver as a module, choose M here: the module
will be called snd-pcm-oss.
config SND_PCM_OSS_PLUGINS
bool "OSS PCM (digital audio) API - Include plugin system"
depends on SND_PCM_OSS
default y
help
If you disable this option, the ALSA's OSS PCM API will not
support conversion of channels, formats and rates. It will
behave like most of new OSS/Free drivers in 2.4/2.6 kernels.
config SND_PCM_TIMER
bool "PCM timer interface" if EXPERT
default y
help
If you disable this option, pcm timer will be unavailable, so
those stubs that use pcm timer (e.g. dmix, dsnoop & co) may work
incorrectly.
For some embedded devices, we may disable it to reduce memory
footprint, about 20KB on x86_64 platform.
config SND_HRTIMER
tristate "HR-timer backend support"
depends on HIGH_RES_TIMERS
select SND_TIMER
help
Say Y here to enable HR-timer backend for ALSA timer. ALSA uses
the hrtimer as a precise timing source. The ALSA sequencer code
also can use this timing source.
To compile this driver as a module, choose M here: the module
will be called snd-hrtimer.
config SND_DYNAMIC_MINORS
bool "Dynamic device file minor numbers"
help
If you say Y here, the minor numbers of ALSA device files in
/dev/snd/ are allocated dynamically. This allows you to have
more than 8 sound cards, but requires a dynamic device file
system like udev.
If you are unsure about this, say N here.
config SND_MAX_CARDS
int "Max number of sound cards"
range 4 256
default 32
depends on SND_DYNAMIC_MINORS
help
Specify the max number of sound cards that can be assigned
on a single machine.
config SND_SUPPORT_OLD_API
bool "Support old ALSA API"
default y
help
Say Y here to support the obsolete ALSA PCM API (ver.0.9.0 rc3
or older).
config SND_PROC_FS
bool "Sound Proc FS Support" if EXPERT
depends on PROC_FS
default y
help
Say 'N' to disable Sound proc FS, which may reduce code size about
9KB on x86_64 platform.
If unsure say Y.
config SND_VERBOSE_PROCFS
bool "Verbose procfs contents"
depends on SND_PROC_FS
default y
help
Say Y here to include code for verbose procfs contents (provides
useful information to developers when a problem occurs). On the
other side, it makes the ALSA subsystem larger.
config SND_CTL_FAST_LOOKUP
bool "Fast lookup of control elements" if EXPERT
default y
select XARRAY_MULTI
help
This option enables the faster lookup of control elements.
It will consume more memory because of the additional Xarray.
If you want to choose the memory footprint over the performance
inevitably, turn this off.
config SND_DEBUG
bool "Debug"
help
Say Y here to enable ALSA debug code.
config SND_DEBUG_VERBOSE
bool "More verbose debug"
depends on SND_DEBUG
help
Say Y here to enable extra-verbose debugging messages.
Let me repeat: it enables EXTRA-VERBOSE DEBUGGING messages.
So, say Y only if you are ready to be annoyed.
config SND_PCM_XRUN_DEBUG
bool "Enable PCM ring buffer overrun/underrun debugging"
default n
depends on SND_DEBUG && SND_VERBOSE_PROCFS
help
Say Y to enable the PCM ring buffer overrun/underrun debugging.
It is usually not required, but if you have trouble with
sound clicking when system is loaded, it may help to determine
the process or driver which causes the scheduling gaps.
config SND_CTL_INPUT_VALIDATION
bool "Validate input data to control API"
help
Say Y to enable the additional validation for the input data to
each control element, including the value range checks.
An error is returned from ALSA core for invalid inputs without
passing to the driver. This is a kind of hardening for drivers
that have no proper error checks, at the cost of a slight
performance overhead.
config SND_CTL_DEBUG
bool "Enable debugging feature for control API"
depends on SND_DEBUG
help
Say Y to enable the debugging feature for ALSA control API.
It performs the additional sanity-checks for each control element
read access, such as whether the values returned from the driver
are in the proper ranges or the check of the invalid access at
out-of-array areas. The error is printed when the driver gives
such unexpected values.
When you develop a driver that deals with control elements, it's
strongly recommended to try this one once and verify whether you see
any relevant errors or not.
config SND_JACK_INJECTION_DEBUG
bool "Sound jack injection interface via debugfs"
depends on SND_JACK && SND_DEBUG && DEBUG_FS
help
This option can be used to enable or disable sound jack
software injection.
Say Y if you are debugging via jack injection interface.
If unsure select "N".
config SND_UTIMER
bool "Enable support for userspace-controlled virtual timers"
depends on SND_TIMER
help
Say Y to enable the support of userspace-controlled timers. These
timers are purely virtual, and they are supposed to be triggered
from userspace. They could be quite useful when synchronizing the
sound timing with userspace applications (for instance, when sending
data through snd-aloop).
config SND_VMASTER
bool
config SND_DMA_SGBUF
def_bool y
depends on X86
config SND_CTL_LED
tristate
select NEW_LEDS if SND_CTL_LED
select LEDS_TRIGGERS if SND_CTL_LED
source "sound/core/seq/Kconfig"
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