DragonFly On-Line Manual Pages

SND_UAUDIO(4)	      DragonFly Kernel Interfaces Manual	 SND_UAUDIO(4)


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 pcm 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. DragonFly 3.9 September 2, 2014 DragonFly 3.9