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diff --git a/static/freebsd/man4/iicmux.4 3.html b/static/freebsd/man4/iicmux.4 3.html deleted file mode 100644 index a5a32816..00000000 --- a/static/freebsd/man4/iicmux.4 3.html +++ /dev/null @@ -1,113 +0,0 @@ -<table class="head"> - <tr> - <td class="head-ltitle">IICMUX(4)</td> - <td class="head-vol">Device Drivers Manual</td> - <td class="head-rtitle">IICMUX(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">iicmux</code> — <span class="Nd">I2C bus - mulitiplexer framework</span></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> -<p class="Pp">To compile this driver into the kernel, place the following line - in your kernel configuration file:</p> -<div class="Bd Pp Bd-indent"><code class="Cd">device iicmux</code></div> -<p class="Pp">Alternatively, to load the driver as a module at boot time, place - the following line in <a class="Xr">loader.conf(5)</a>:</p> -<div class="Bd Pp Bd-indent Li"> -<pre>iicmux_load="YES"</pre> -</div> -<p class="Pp">Note that it is usually not necessary to explicitly load the - driver module, as it will be loaded automatically along with the driver for - the specific mux hardware in use.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> -<p class="Pp">The <code class="Nm">iicmux</code> framework provides support code - to help implement drivers for various I2C bus multiplexer (mux) hardware. - <code class="Nm">iicmux</code> is not a standalone driver, it is a - collection of support functions and driver methods which are used by - individual mux hardware drivers. It will be loaded automatically when needed - by a mux hardware driver. This manual page provides an overview of the I2C - mux framework and its behavior.</p> -<p class="Pp">Generally speaking, an I2C mux is connected to an upstream I2C - bus, and to one or more downstream I2C buses, and it can be commanded to - connect any one of the downstream buses to the upstream bus. Some hardware - may be able to connect multiple downstream buses at the same time, but that - concept is not supported by <code class="Nm">iicmux</code>.</p> -<p class="Pp">The <code class="Nm">iicmux</code> framework operates - automatically when I2C slave devices initiate I/O. It does not require (or - even allow for) any external control to select the active downstream - bus.</p> -<p class="Pp">When there is no I/O in progress, the mux is said to be in the - “idle” state. Some mux hardware has the ability to disconnect - all downstream buses when in an idle state. Other hardware must always have - one of the downstream buses connected. Individual mux hardware drivers - typically provide a way to select which downstream bus (if any) should be - connected while in the idle state. In the absence of such configuration, - whichever downstream bus was last used remains connected to the upstream - bus.</p> -<p class="Pp" id="iicbus_request_bus">When an I2C slave device on a bus - downstream of a mux initiates I/O, it first requests exclusive use of the - bus by calling - <a class="permalink" href="#iicbus_request_bus"><code class="Fn">iicbus_request_bus</code></a>(). - This request is communicated to the bus's parent, which is the - <code class="Nm">iicmux</code> framework mux driver. Once exclusive bus - ownership is obtained, the mux driver connects the upstream I2C bus to the - downstream bus which hosts the slave device that requested bus ownership. - The mux hardware maintains that upstream-to-downstream connection until the - slave device calls - <a class="permalink" href="#iicbus_release_bus"><code class="Fn" id="iicbus_release_bus">iicbus_release_bus</code></a>(). - Before releasing ownership, the mux driver returns the mux hardware to the - idle state.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="FDT_CONFIGURATION"><a class="permalink" href="#FDT_CONFIGURATION">FDT - CONFIGURATION</a></h1> -<p class="Pp">On an <a class="Xr">fdt(4)</a> based system, an I2C mux device - node is defined as a child node of its upstream I2C bus when the mux device - is an I2C slave itself. It may be defined as a child node of any other bus - or device in the system when it is not an I2C slave, in which case the - <var class="Va">i2c-parent</var> property indicates which upstream bus the - mux is attached to. In either case, the children of the mux node are - additional I2C buses, which will have one or more I2C slave devices - described in their child nodes.</p> -<p class="Pp">Drivers using the <code class="Nm">iicmux</code> framework conform - to the standard <code class="Li">i2c/i2c-mux.txt</code> bindings - document.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="HINTS_CONFIGURATION"><a class="permalink" href="#HINTS_CONFIGURATION">HINTS - CONFIGURATION</a></h1> -<p class="Pp">On a <a class="Xr">device.hints(5)</a> based system, these values - are configurable for <code class="Nm">iicmux</code> framework drivers :</p> -<dl class="Bl-tag"> - <dt id="hint._driver_._unit_.at"><var class="Va">hint.<driver>.<unit>.at</var></dt> - <dd>The upstream <a class="Xr">iicbus(4)</a> the - <code class="Nm">iicmux</code> instance is attached to.</dd> -</dl> -<p class="Pp">When configured via hints, the driver automatically adds an iicbus - instance for every downstream bus supported by the chip. There is currently - no way to indicate used versus unused downstream buses.</p> -</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">iicbus(4)</a></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">iicmux</code> framework first appeared in - <span class="Ux">FreeBSD 13.0</span>.</p> -</section> -</div> -<table class="foot"> - <tr> - <td class="foot-date">January 1, 2020</td> - <td class="foot-os">FreeBSD 15.0</td> - </tr> -</table> |