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ALSA: docs: Add documents for recently changes in snd-usb-audio

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Changed:
  - ignore_ctl_error
  - lowlatency
  - skip_validation
  - quirk_flags[19:24]

[ corrected a typo -- tiwai ]

Signed-off-by: Cryolitia PukNgae <cryolitia@uniontech.com>
Link: https://patch.msgid.link/20250829-sound-doc-v1-1-e0110452b03d@uniontech.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Cryolitia PukNgae 2025-08-29 16:46:06 +08:00 committed by Takashi Iwai
parent 3e93d5bbcb
commit 78811dd56d
1 changed files with 25 additions and 4 deletions
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29
Documentation/sound/alsa-configuration.rst
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@ -2253,8 +2253,15 @@ device_setup
Default: 0x0000
ignore_ctl_error
Ignore any USB-controller regarding mixer interface (default: no)
``ignore_ctl_error=1`` may help when you get an error at accessing
the mixer element such as URB error -22. This happens on some
buggy USB device or the controller. This workaround corresponds to
the ``quirk_flags`` bit 14, too.
autoclock
Enable auto-clock selection for UAC2 devices (default: yes)
lowlatency
Enable low latency playback mode (default: yes).
Could disable it to switch back to the old mode if face a regression.
quirk_alias
Quirk alias list, pass strings like ``0123abcd:5678beef``, which
applies the existing quirk for the device 5678:beef to a new
@ -2284,6 +2291,11 @@ delayed_register
The driver prints a message like "Found post-registration device
assignment: 1234abcd:04" for such a device, so that user can
notice the need.
skip_validation
Skip unit descriptor validation (default: no).
The option is used to ignores the validation errors with the hexdump
of the unit descriptor instead of a driver probe error, so that we
can check its details.
quirk_flags
Contains the bit flags for various device specific workarounds.
Applied to the corresponding card index.
@ -2307,6 +2319,16 @@ quirk_flags
* bit 16: Set up the interface at first like UAC1
* bit 17: Apply the generic implicit feedback sync mode
* bit 18: Don't apply implicit feedback sync mode
* bit 19: Don't closed interface during setting sample rate
* bit 20: Force an interface reset whenever stopping & restarting
a stream
* bit 21: Do not set PCM rate (frequency) when only one rate is
available for the given endpoint.
* bit 22: Set the fixed resolution 16 for Mic Capture Volume
* bit 23: Set the fixed resolution 384 for Mic Capture Volume
* bit 24: Set minimum volume control value as mute for devices
where the lowest playback value represents muted state instead
of minimum audible volume
This module supports multiple devices, autoprobe and hotplugging.
@ -2314,10 +2336,9 @@ NB: ``nrpacks`` parameter can be modified dynamically via sysfs.
Don't put the value over 20. Changing via sysfs has no sanity
check.
NB: ``ignore_ctl_error=1`` may help when you get an error at accessing
the mixer element such as URB error -22. This happens on some
buggy USB device or the controller. This workaround corresponds to
the ``quirk_flags`` bit 14, too.
NB: ``ignore_ctl_error=1`` just provides a quick way to work around the
issues. If you have a buggy device that requires these quirks, please
report it to the upstream.
NB: ``quirk_alias`` option is provided only for testing / development.
If you want to have a proper support, contact to upstream for