Ubuntu Manpages

snd_uaudio

USB audio and MIDI device driver

To compile this driver into the kernel, place the following lines in your kernel configuration file:

device sound
device usb
device snd_uaudio

Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

snd_uaudio_load="YES"

The snd_uaudio driver provides support for USB audio class devices and USB MIDI class devices.

A USB audio device consists of a number of components: input terminals (e.g. USB digital input), output terminals (e.g. speakers), and a number of units in between (e.g. volume control).

Refer to the ‘USB Audio Class Specification’ for more information.

sound(4), usb(4)

USB Audio Class Specifications, http://www.usb.org/developers/devclass_docs/.

The snd_uaudio driver first appeared in FreeBSD 4.7.

This manual page was adopted from NetBSD 1.6 and modified for FreeBSD by Hiten Pandya ⟨hmp@FreeBSD.org⟩.

The PCM framework in FreeBSD, as of this writing, does not handle device un-registrations in a properly abstracted manner, i.e., a detach request is refused by the PCM framework if the device is in use. It is necessary to allow the device un-registration to complete successfully, otherwise the PCM layer will panic.