ALSA: doc: Add the description of quirk_flags option for snd-usb-audio

Just briefly described about the new option.

Link: https://lore.kernel.org/r/20210729074404.19728-6-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2021-07-29 09:44:04 +02:00
parent 5b51785442
commit a39978ed6d

View File

@ -2252,6 +2252,25 @@ 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.
quirk_flags
Contains the bit flags for various device specific workarounds.
Applied to the corresponding card index.
* bit 0: Skip reading sample rate for devices
* bit 1: Create Media Controller API entries
* bit 2: Allow alignment on audio sub-slot at transfer
* bit 3: Add length specifier to transfers
* bit 4: Start playback stream at first in implement feedback mode
* bit 5: Skip clock selector setup
* bit 6: Ignore errors from clock source search
* bit 7: Indicates ITF-USB DSD based DACs
* bit 8: Add a delay of 20ms at each control message handling
* bit 9: Add a delay of 1-2ms at each control message handling
* bit 10: Add a delay of 5-6ms at each control message handling
* bit 11: Add a delay of 50ms at each interface setup
* bit 12: Perform sample rate validations at probe
* bit 13: Disable runtime PM autosuspend
* bit 14: Ignore errors for mixer access
* bit 15: Support generic DSD raw U32_BE format
This module supports multiple devices, autoprobe and hotplugging.
@ -2261,11 +2280,14 @@ 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.
buggy USB device or the controller. This workaround corresponds to
the ``quirk_flags`` bit 14, too.
NB: quirk_alias option is provided only for testing / development.
NB: ``quirk_alias`` option is provided only for testing / development.
If you want to have a proper support, contact to upstream for
adding the matching quirk in the driver code statically.
Ditto for ``quirk_flags``. If a device is known to require specific
workarounds, please report to the upstream.
Module snd-usb-caiaq
--------------------