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diff --git a/static/freebsd/man4/snd_uaudio.4 3.html b/static/freebsd/man4/snd_uaudio.4 3.html new file mode 100644 index 00000000..7f37619b --- /dev/null +++ b/static/freebsd/man4/snd_uaudio.4 3.html @@ -0,0 +1,149 @@ +<table class="head"> + <tr> + <td class="head-ltitle">SND_UAUDIO(4)</td> + <td class="head-vol">Device Drivers Manual</td> + <td class="head-rtitle">SND_UAUDIO(4)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">snd_uaudio</code> — <span class="Nd">USB + audio and MIDI device driver</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp"><code class="Cd">device sound</code> + <br/> + <code class="Cd">device usb</code> + <br/> + <code class="Cd">device snd_uaudio</code></p> +<p class="Pp">In <a class="Xr">rc.conf(5)</a>: + <br/> + <code class="Cd">kld_list="snd_uaudio"</code></p> +<p class="Pp">In <a class="Xr">sysctl.conf(5)</a>: + <br/> + <code class="Cd">hw.usb.uaudio.buffer_ms</code> + <br/> + <code class="Cd">hw.usb.uaudio.default_bits</code> + <br/> + <code class="Cd">hw.usb.uaudio.default_channels</code> + <br/> + <code class="Cd">hw.usb.uaudio.default_rate</code> + <br/> + <code class="Cd">hw.usb.uaudio.handle_hid</code> + <br/> + <code class="Cd">hw.usb.uaudio.debug</code></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">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).</p> +<p class="Pp">If the device supports multiple configurations, and there have + been no user-supplied values specified through the + <a class="Xr">sysctl(8)</a> interface, the driver will select the best + matching configuration supported by the device during attach. + "Best" means the configuration with the most channels and highest + quality in sample rate and sample size.</p> +<p class="Pp">Refer to the ‘<code class="Li">USB Audio Class + Specification</code>’ for more information.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HARDWARE"><a class="permalink" href="#HARDWARE">HARDWARE</a></h1> +<p class="Pp">The <code class="Nm">snd_uaudio</code> driver provides support for + USB audio class devices and USB MIDI class devices.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYSCTL_VARIABLES"><a class="permalink" href="#SYSCTL_VARIABLES">SYSCTL + VARIABLES</a></h1> +<p class="Pp">The following settings can be entered at the + <a class="Xr">loader(8)</a> prompt or in <a class="Xr">loader.conf(5)</a> + and can also be changed at runtime with the <a class="Xr">sysctl(8)</a> + command. For a change to take effect during runtime, the device has to be + re-attached.</p> +<dl class="Bl-tag"> + <dt id="hw.usb.uaudio.buffer_ms"><var class="Va">hw.usb.uaudio.buffer_ms</var></dt> + <dd>Period of audio data processed at once, in milliseconds, from 1 to 8 + (default is 4). Lower values mean less latency, but this can result in + audible gaps due to frequent CPU wakeups.</dd> + <dt id="hw.usb.uaudio.default_bits"><var class="Va">hw.usb.uaudio.default_bits</var></dt> + <dd>Preferred sample size in bits, from 0 to 32 (default is 0). A value of 0 + sets the sample size to the maximum supported sample size. + <p class="Pp">Set this to select a smaller sample size if the device + supports multiple sample sizes.</p> + </dd> + <dt id="hw.usb.uaudio.default_channels"><var class="Va">hw.usb.uaudio.default_channels</var></dt> + <dd>Preferred number of sample channels, from 0 to 64 (default is 0). USB 1.1 + devices are limited to 4 channels due to bandwidth constraints, unless a + higher value is explicitly requested. A value of 0 sets the sample + channels to the maximum supported channel number. + <p class="Pp">Set this to select a smaller channel number if the device + supports multiple channel configurations.</p> + </dd> + <dt id="hw.usb.uaudio.default_rate"><var class="Va">hw.usb.uaudio.default_rate</var></dt> + <dd>Preferred sample rate in Hz (default is 0). If set to 0, the device's + highest supported sample rate will be used. + <p class="Pp">Note that if VCHANs are enabled, the sample rate will be + overridden by <span class="Pa">dev.pcm.%d.[play|rec].vchanrate</span> + (see <a class="Xr">sound(4)</a>), which can also be used to adjust the + sample rate during runtime.</p> + <p class="Pp">If <span class="Pa">hw.usb.uaudio.default_rate</span> is + non-zero, <span class="Pa">dev.pcm.%d.[play|rec].vchanrate</span> will + use it as its maximum allowed value.</p> + </dd> + <dt id="hw.usb.uaudio.handle_hid"><var class="Va">hw.usb.uaudio.handle_hid</var></dt> + <dd>Let <code class="Nm">snd_uaudio</code> handle HID volume keys, if any + (default is 1). + <dl class="Bl-tag"> + <dt>0</dt> + <dd>Disabled.</dd> + <dt>1</dt> + <dd>Enabled.</dd> + </dl> + </dd> +</dl> +<p class="Pp">If <a class="Xr">usb(4)</a> has been compiled with + <var class="Va">USB_DEBUG</var> on, the following setting is also + available:</p> +<dl class="Bl-tag"> + <dt id="hw.usb.uaudio.debug"><var class="Va">hw.usb.uaudio.debug</var></dt> + <dd>Debug output level (default is 0).</dd> +</dl> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">sound(4)</a>, <a class="Xr">usb(4)</a>, + <a class="Xr">loader.conf(5)</a>, <a class="Xr">loader(8)</a>, + <a class="Xr">sysctl(8)</a></p> +<p class="Pp"><cite class="Rs"><span class="RsT">USB Audio Class + Specifications</span>, + <a class="RsU" href="http://www.usb.org/developers/docs/devclass_docs/">http://www.usb.org/developers/docs/devclass_docs/</a>.</cite></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">The <code class="Nm">snd_uaudio</code> driver first appeared in + <span class="Ux">FreeBSD 4.7</span>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> +<p class="Pp">This manual page was adopted from <span class="Ux">NetBSD + 1.6</span> and modified for <span class="Ux">FreeBSD</span> by + <span class="An">Hiten Pandya</span> + <<a class="Mt" href="mailto:hmp@FreeBSD.org">hmp@FreeBSD.org</a>>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="BUGS"><a class="permalink" href="#BUGS">BUGS</a></h1> +<p class="Pp">The PCM framework in <span class="Ux">FreeBSD</span> currently + does not support the full set of USB audio mixer controls. Some mixer + controls are only available as <var class="Va">dev.pcm.%d.mixer</var> + sysctls.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">July 17, 2025</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |