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diff --git a/static/freebsd/man9/OF_node_from_xref.9 b/static/freebsd/man9/OF_node_from_xref.9 new file mode 100644 index 00000000..755c8295 --- /dev/null +++ b/static/freebsd/man9/OF_node_from_xref.9 @@ -0,0 +1,99 @@ +.\" +.\" SPDX-License-Identifier: BSD-2-Clause +.\" +.\" Copyright (c) 2018 Oleksandr Tymoshenko <gonzo@FreeBSD.org> +.\" +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR +.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, +.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.\" +.Dd April 9, 2018 +.Dt OF_NODE_FROM_XREF 9 +.Os +.Sh NAME +.Nm OF_node_from_xref , +.Nm OF_xref_from_node +.Nd convert between kernel phandle and effective phandle +.Sh SYNOPSIS +.In dev/ofw/ofw_bus.h +.In dev/ofw/ofw_bus_subr.h +.Ft phandle_t +.Fn OF_node_from_xref "phandle_t xref" +.Ft phandle_t +.Fn OF_xref_from_node "phandle_t node" +.Sh DESCRIPTION +Some OpenFirmware implementations (FDT, IBM) have a concept +of effective phandle or xrefs. +They are used to cross-reference device tree nodes. +For instance, a framebuffer controller may refer to a GPIO +controller and pin that controls the backlight. +In this example, the GPIO node would have a cell (32-bit integer) +property with a reserved name like "phandle" or "linux,phandle" +whose value uniquely identifies the node. +The actual name depends on the implementation. +The framebuffer node would have a property with the name +described by device bindings (device-specific set of properties). +It can be a cell property or a combined property with one part +of it being a cell. +The value of the framebuffer node's property would be the same +as the value of the GPIO "phandle" property so it can be said +that the framebuffer node refers to the GPIO node. +The kernel uses internal logic to assign unique identifiers +to the device tree nodes, and these values do not match +the values of "phandle" properties. +.Fn OF_node_from_xref +and +.Fn OF_xref_from_node +are used to perform conversion between these two kinds of node +identifiers. +.Pp +.Fn OF_node_from_xref +returns the kernel phandle for the effective phandle +.Fa xref . +If one cannot be found or the OpenFirmware implementation +does not support effective phandles, the function returns +the input value. +.Pp +.Fn OF_xref_from_node +returns the effective phandle for the kernel phandle +.Fa node . +If one cannot be found or the OpenFirmware implementation +does not support effective phandles, the function returns +the input value. +.Sh EXAMPLES +.Bd -literal + phandle_t panelnode, panelxref; + char *model; + + if (OF_getencprop(node, "lcd-panel", &panelxref) <= 0) + return; + + panelnode = OF_node_from_xref(panelxref); + if (OF_getprop_alloc(hdminode, "model", (void **)&model) <= 0) + return; +.Ed +.Sh SEE ALSO +.Xr OF_device_from_xref 9 , +.Xr OF_device_register_xref 9 +.Sh AUTHORS +.An -nosplit +This manual page was written by +.An Oleksandr Tymoshenko Aq Mt gonzo@FreeBSD.org . |