diff options
| -rw-r--r-- | share/man/man4/Makefile | 1 | ||||
| -rw-r--r-- | share/man/man4/gpio.4 | 176 | ||||
| -rw-r--r-- | usr.sbin/gpioctl/gpioctl.8 | 4 |
3 files changed, 180 insertions, 1 deletions
diff --git a/share/man/man4/Makefile b/share/man/man4/Makefile index e51ad39..e221795 100644 --- a/share/man/man4/Makefile +++ b/share/man/man4/Makefile @@ -154,6 +154,7 @@ MAN= aac.4 \ geom_uzip.4 \ gif.4 \ gpib.4 \ + gpio.4 \ gre.4 \ h_ertt.4 \ hatm.4 \ diff --git a/share/man/man4/gpio.4 b/share/man/man4/gpio.4 new file mode 100644 index 0000000..2053df1 --- /dev/null +++ b/share/man/man4/gpio.4 @@ -0,0 +1,176 @@ +.\" Copyright (c) 2013, Sean Bruno <sbruno@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. +.\" +.\" $FreeBSD$ +.\" +.Dd September 13, 2013 +.Dt GPIO 4 +.Os +.Sh NAME +.Nm gpiobus +.Nd GPIO bus system +.Sh SYNOPSIS +To compile these devices into your kernel and use the device hints, place the +following lines in your kernel configuration file: +.Bd -ragged -offset indent +.Cd "device gpiobus" +.Cd "device gpioiic" +.Cd "device gpio" +.Cd "device gpioc" +.Cd "device gpioled" +.Ed +.Pp +Additional device entries for the +.Li ARM +architecure include: +.Bd -ragged -offset indent +.Cd "device a10_gpio" +.Cd "device bcm_gpio" +.Cd "device imx51_gpio" +.Cd "device lpcgpio" +.Cd "device mv_gpio" +.Cd "device ti_gpio" +.Cd "device gpio_avila" +.Cd "device gpio_cambria" +.Cd "device zy7_gpio" +.Cd "device pxagpio" +.Ed +.Pp +Additional device entries for the +.Li MIPS +architecure include: +.Bd -ragged -offset indent +.Cd "device ar71xxx_gpio" +.Cd "device octeon_gpio" +.Cd "device rt305_gpio" +.Ed +.Pp +Additional device entries for the +.Li POWERPC +architecure include: +.Bd -ragged -offset indent +.Cd "device wiigpio" +.Cd "device macgpio" +.Ed +.Sh DESCRIPTION +The +.Em gpiobus +system provides a simple interface to the bit banging style GPIO bus +found on embedded architectures. +.Pp +The acronym +.Li GPIO +means +.Dq General-Purpose Input/Output. +.Pp +The BUS physically consists of multiple pins that can be configured +for input/output, IRQ delivery, SDA/SCL +.Em iicbus +use, etc. +On most embedded architechtures (mips/arm), discovery of the bus and +configuration of the pins is done via +.Xr device.hints 5 +in the platform's kernel +.Xr config 5 +file. +.Pp +Assignment of +.Xr gpioiic 4 +bus variables is done via: +.Bl -tag -width ".Va hint.gpioiic.%d.atXXX" +.It Va hint.gpioiic.%d.at +Normally just gpiobus0. +.It Va hint.gpioiic.%d.pins +This is a bitmask of the pins on the gpio board that are to be used for +SCLOCK and SDATA from the IIC bus. +To configure pin 0 and 7, use the bitmask of +10000001 and convert it to a hexadecimal value of 0x0081. +Should only ever have two bits set in mask. +.It Va hint.gpioiic.%d.scl +Indicates which bit in the +.Va hint.gpioiic.%d.pins +should be used as the SCLOCK +source. +.It Va hint.gpioiic.%d.sda +Indicates which bit in the +.Va hint.gpioiic.%d.pins +should be used as the SDATA +source. +.El +.Pp +The following are only provided by the +.Cd ar71xx_gpio +driver. +.Bl -tag -width ".Va hint.gpioiic.%d.atXXX" +.It Va hint.gpio.%d.pinmask +This is a bitmask of pins on the gpio board that we would like to expose +for use to the host o/s. +To expose pin 0, 4 and 7, use the bitmask of +10010001 converted to the hexadecimal value 0x0091. +.It Va hint.gpio.%d.pinon +This is a bitmask of pins on the gpio board that will be set to ON at host +start. +To set pin 2, 5 and 13 to be set ON at boot, use the bitmask of +10000000010010 converted to the hexadecimal value 0x2022. +.It Va hint.gpio.function_set +.It Va hint.gpio.function_clear +These are a bitmask of pins that will remap a pin to handle a specific +function (USB, UART TX/RX, etc) in the Atheros function registers. +This is mainly used to set/clear functions that we need when they are setup or +not setup by uBoot. +.El +.Pp +These values are configureable from the +.Xr gpioled 4 +interface and help create +.Xr led 4 +compatible devices in +.Pa /dev/led/<name> . +.Bl -tag -width ".Va hint.gpioiic.%d.atXXX" +.It Va hint.gpioled.%d.at +Normally assigned to gpiobus0. +.It Va hint.gpioled.%d.name +Arbitrary name of device in +.Pa /dev/led/ +to create for +.Xr led 4 +interfaces. +.It Va hint.gpioled.%d.pins +Which pin on the GPIO interface to map to this instance. +.El +.Pp +Simply put, each pin of the GPIO interface is connected to an input/output +of some device in a system. +.Sh SEE ALSO +.Xr iicbus 4 , +.Xr gpioctl 8 +.Sh HISTORY +The +.Nm +manual page first appeared in +.Fx 10.0 . +.Sh AUTHORS +This +manual page was written by +.An Sean Bruno Aq sbruno@FreeBSD.org . diff --git a/usr.sbin/gpioctl/gpioctl.8 b/usr.sbin/gpioctl/gpioctl.8 index 32ae409..ab936a4 100644 --- a/usr.sbin/gpioctl/gpioctl.8 +++ b/usr.sbin/gpioctl/gpioctl.8 @@ -27,7 +27,7 @@ .\" .\" $FreeBSD$ .\" -.Dd May 25, 2011 +.Dd August 13, 2013 .Dt GPIOCTL 1 .Os .Sh NAME @@ -105,6 +105,8 @@ Configure pin 12 to be input pin .Pp gpioctl -f /dev/gpioc0 -c 12 IN .El +.Sh SEE ALSO +.Xr gpio 4 .Sh HISTORY The .Nm |
