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Diffstat (limited to 'static/freebsd/man4/gpioled.4')
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diff --git a/static/freebsd/man4/gpioled.4 b/static/freebsd/man4/gpioled.4 new file mode 100644 index 00000000..45457d20 --- /dev/null +++ b/static/freebsd/man4/gpioled.4 @@ -0,0 +1,173 @@ +.\" Copyright (c) 2013, Luiz Otavio O Souza <loos@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 AUTHOR AND CONTRIBUTORS ``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 AUTHOR OR CONTRIBUTORS 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 May 23, 2019 +.Dt GPIOLED 4 +.Os +.Sh NAME +.Nm gpioled +.Nd GPIO LED generic device driver +.Sh SYNOPSIS +To compile this driver into the kernel, +place the following lines in your +kernel configuration file: +.Bd -ragged -offset indent +.Cd "device gpio" +.Cd "device gpioled" +.Ed +.Sh DESCRIPTION +The +.Nm +driver provides glue to attach a +.Xr led 4 +compatible device to a GPIO pin. +Each LED in the system has a +.Pa name +which is used to export a device as +.Pa /dev/led/<name> . +The GPIO pin can then be controlled by writing to this device as described +in +.Xr led 4 . +.Pp +On a +.Xr device.hints 5 +based system, like +.Li MIPS , +these values are configurable for +.Nm : +.Bl -tag -width ".Va hint.gpioiic.%d.atXXX" +.It Va hint.gpioled.%d.at +The gpiobus you are attaching to. +Normally assigned to gpiobus0. +.It Va hint.gpioled.%d.name +Arbitrary name of device in +.Pa /dev/led/ +to create for +.Xr led 4 . +.It Va hint.gpioled.%d.pins +Which pin on the GPIO interface to map to this instance. +Please note that this mask should only ever have one bit set +(any other bits - i.e., pins - will be ignored). +.It Va hint.gpioled.%d.invert +Use pin inversion. If set to 1, the pin will be set to 0 to light the LED, and 1 +to clear it. +.It Va hint.gpioled.%d.invmode +Whether or not to use hardware support when pin inversion is requested. Must be +one of: +.Bl -tag +.It Va auto +Use hardware pin inversion if available, else fallback to software pin +inversion. This is the default. +.It Va hw +Use hardware pin inversion. +.It Va sw +Use software pin inversion. +.El +.It Va hint.gpioled.%d.state +The initial state of the LED when the driver takes control over it. +If set to 1 or 0, the LED will be on or off correspondingly. +If set to -1, the LED will be kept in its original state. +.El +.Pp +On a +.Xr FDT 4 +based system, like +.Li ARM , +the DTS part for a +.Nm gpioled +device usually looks like: +.Bd -literal +gpio: gpio { + + gpio-controller; + ... + + led0 { + compatible = "gpioled"; + gpios = <&gpio 16 2 0>; /* GPIO pin 16. */ + name = "ok"; + }; + + led1 { + compatible = "gpioled"; + gpios = <&gpio 17 2 0>; /* GPIO pin 17. */ + name = "user-led1"; + }; +}; +.Ed +.Pp +Optionally, you can choose to combine all the LEDs under a single +.Dq gpio-leds +compatible node: +.Bd -literal +simplebus0 { + + ... + + leds { + compatible = "gpio-leds"; + + led0 { + gpios = <&gpio 16 2 0>; + name = "ok" + }; + + led1 { + gpios = <&gpio 17 2 0>; + name = "user-led1" + }; + }; +}; +.Ed +.Pp +Both methods are equally supported and it is possible to have the LEDs +defined with any sort of mix between the methods. +The only restriction is that a GPIO pin cannot be mapped by two different +(gpio)leds. +.Pp +For more details about the +.Va gpios +property, please consult +.Pa /usr/src/sys/dts/bindings-gpio.txt . +.Pp +The property +.Va name +is the arbitrary name of the device in +.Pa /dev/led/ +to create for +.Xr led 4 . +.Sh SEE ALSO +.Xr fdt 4 , +.Xr gpio 4 , +.Xr gpioiic 4 , +.Xr led 4 +.Sh HISTORY +The +.Nm +manual page first appeared in +.Fx 10.1 . +.Sh AUTHORS +This +manual page was written by +.An Luiz Otavio O Souza . |