USB_AS(4D) USB_AS(4D)


NAME


usb_as - USB audio streaming driver

SYNOPSIS


sound@unit-address


DESCRIPTION


The usb_as driver is a USBA (Solaris USB Architecture) compliant client
driver that supports the USB Audio Class 1.0 specification.


The usb_as driver processes audio data messages during play and record
and sets sample frequency, precision, encoding and other functions on
request from the USB audio control driver. See usb_ac(4D).


This driver is plumbed under the USB audio control driver and does not
directly interface with the user application.

FILES


/kernel/drv/usb_as
32-bit x86 ELF kernel module


/kernel/drv/amd64/usb_as
64-bit x86 ELF kernel module


/kernel/drv/sparcv9/usb_as
64-bit SPARC ELF kernel module


ATTRIBUTES


See attributes(7) for descriptions of the following attributes:


+-----------------+-------------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------+-------------------------------+
|Architecture | SPARC, x86, PCI-based systems |
+-----------------+-------------------------------+
|Stability level | Committed |
+-----------------+-------------------------------+

SEE ALSO


usb_ac(4D), usba(4D), audio(4I), attributes(7)


Writing Device Drivers


Universal Serial Bus Specification 1.0 and 1.1


System Administration Guide: Basic Administration

DIAGNOSTICS


In addition to being logged, the following messages can appear on the
system console. All messages are formatted in the following manner:

Warning: <device path> (usb_as<instance num>): Error Message...


where <device path> is the physical path to the device in /devices
directory.

No bandwidth available.

There is no bandwidth available for the isochronous pipe. As a
result, no data is transferred during play and record.


Operating a full/high speed audio device on a high speed port is not
supported.

The USB software does not currently support full or high speed audio
devices connected to an external USB 2.0 hub that is linked to a port
of a USB 2.0 host controller. Audio devices must be connected
directly to a port of a USB 2.0 controller or to any USB 1.1 port.


Cannot access device. Please reconnect <name>.

There was an error in accessing the device during reconnect. Please
reconnect the device.


Device is not identical to the previous one on this port. Please
disconnect and reconnect.

A USB audio streaming interface was hot-removed while open. A new
device was hot-inserted which is not identical to the original USB
audio device. Please disconnect the USB device and reconnect the
device to the same port.


NOTES


The USB audio streaming interface is power managed if the device is idle.


May 15, 2009 USB_AS(4D)