MFC r258044, r258679, r263990

Adds gpioiic.4 and gpioled.4 man pages.  Moves some of the information that
was previously available on gpio.4 to their respectives pages.  Add the
cross references on gpioctl.8.

Add gpiobus(4) as a link to gpio(4).

5 files changed, 200 insertions, 49 deletions

diff --git a/share/man/man4/Makefile b/share/man/man4/Makefile
index def02c7..f52cc6d 100644
--- a/share/man/man4/Makefile
+++ b/share/man/man4/Makefile
@@ -157,6 +157,8 @@ MAN=	aac.4 \
 	gif.4 \
 	gpib.4 \
 	gpio.4 \
+	gpioiic.4 \
+	gpioled.4 \
 	gre.4 \
 	h_ertt.4 \
 	hatm.4 \
@@ -635,6 +637,7 @@ MLINKS+=fxp.4 if_fxp.4
 MLINKS+=gem.4 if_gem.4
 MLINKS+=geom.4 GEOM.4
 MLINKS+=gif.4 if_gif.4
+MLINKS+=gpio.4 gpiobus.4
 MLINKS+=gre.4 if_gre.4
 MLINKS+=hatm.4 if_hatm.4
 MLINKS+=hme.4 if_hme.4
diff --git a/share/man/man4/gpio.4 b/share/man/man4/gpio.4
index 614a722..f0bd8a3 100644
--- a/share/man/man4/gpio.4
+++ b/share/man/man4/gpio.4
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd September 13, 2013
+.Dd November 5, 2013
 .Dt GPIO 4
 .Os
 .Sh NAME
@@ -34,10 +34,9 @@
 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 gpioiic"
 .Cd "device gpioled"
 .Ed
 .Pp
@@ -76,8 +75,9 @@ architecure include:
 .Sh DESCRIPTION
 The
 .Em gpiobus
-system provides a simple interface to the bit banging style GPIO bus
-found on embedded architectures.
+system provides a simple interface to the GPIO pins that are usually
+available on embedded architectures and can provide bit banging style
+devices to the system.
 .Pp
 The acronym
 .Li GPIO
@@ -88,36 +88,20 @@ 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
+.Pp
+On some embedded architechtures (like MIPS), 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
+On some others (like ARM), where
+.Xr FDT 4
+is used to describe the device tree, the bus discovery is done via the DTS
+passed to the kernel, being either statically compiled in, or by a variety
+of ways where the boot loader (or Open Firmware enabled system) passes the
+DTS blob to kernel at boot.
 .Pp
 The following are only provided by the
 .Cd ar71xx_gpio
@@ -141,28 +125,11 @@ 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 gpioiic 4 ,
+.Xr gpioled 4 ,
 .Xr iicbus 4 ,
 .Xr gpioctl 8
 .Sh HISTORY
diff --git a/share/man/man4/gpioiic.4 b/share/man/man4/gpioiic.4
new file mode 100644
index 0000000..cbcaec9
--- /dev/null
+++ b/share/man/man4/gpioiic.4
@@ -0,0 +1,96 @@
+.\" 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.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd November 5, 2013
+.Dt GPIOIIC 4
+.Os
+.Sh NAME
+.Nm gpioiic
+.Nd GPIO I2C bit-banging device driver
+.Sh SYNOPSIS
+.Cd "device gpio"
+.Cd "device gpioiic"
+.Cd "device iic"
+.Cd "device iicbb"
+.Cd "device iicbus"
+.Sh DESCRIPTION
+The
+.Em gpioiic
+driver provides an IIC bit-banging interface using two GPIO pins for the
+SCL and SDA on the
+.Em gpiobus .
+.Nm
+implements an open colector kind of output, as recommended by the standard,
+when driving the pins on the
+.Em gpiobus ,
+i.e, they are never switched to the logical value of '1',
+or they are '0' or simply open (Hi-Z/tri-state).
+So the pullup resistors are required so
+.Nm
+can work.
+.Pp
+On a hint based system, like
+.Li MIPS , these values are configureable for the
+.Nm gpioiic :
+.Bl -tag -width ".Va hint.gpioiic.%d.atXXX"
+.It Va hint.gpioiic.%d.at
+The gpiobus you are attaching to.
+Normally just gpiobus0.
+.It Va hint.gpioiic.%d.pins
+This is a bitmask of the pins on the
+.Em gpiobus
+that are to be used for SCLOCK and SDATA from the GPIO IIC
+bit-banging bus.
+To configure pin 0 and 7, use the bitmask of
+10000001 and convert it to a hexadecimal value of 0x0081.
+Please note that this mask should only ever have two bits set
+(any others bits - i.e., pins - will be ignored).
+.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
+.Sh SEE ALSO
+.Xr gpio 4 ,
+.Xr gpioled 4 ,
+.Xr iic 4 ,
+.Xr iicbb 4 ,
+.Xr iicbus 4
+.Sh HISTORY
+The
+.Nm
+manual page first appeared in
+.Fx 11.0 .
+.Sh AUTHORS
+This
+manual page was written by
+.An Luiz Otavio O Souza .
diff --git a/share/man/man4/gpioled.4 b/share/man/man4/gpioled.4
new file mode 100644
index 0000000..76f59fa
--- /dev/null
+++ b/share/man/man4/gpioled.4
@@ -0,0 +1,83 @@
+.\" 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.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd November 5, 2013
+.Dt GPIOLED 4
+.Os
+.Sh NAME
+.Nm gpioled
+.Nd GPIO led generic device driver
+.Sh SYNOPSIS
+.Cd "device gpio"
+.Cd "device gpioled"
+.Pp
+This driver attaches a
+.Xr led 4
+device to a GPIO pin.
+.Sh DESCRIPTION
+The
+.Em gpioled
+driver provides a glue to attach a
+.Xr led 4
+compatible device to a GPIO pin.
+Each led on the system has a
+.Pa name
+which is used to export a device in
+.Pa /dev/led/<name> .
+The GPIO pin can then be controlled by writing to this device as described
+on
+.Xr led 4 .
+.Pp
+On a hint based system, like
+.Li MIPS , these values are configureable 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 others bits - i.e., pins - will be ignored).
+.El
+.Sh SEE ALSO
+.Xr gpio 4 ,
+.Xr led 4 ,
+.Xr gpioiic 4
+.Sh HISTORY
+The
+.Nm
+manual page first appeared in
+.Fx 11.0 .
+.Sh AUTHORS
+This
+manual page was written by
+.An Luiz Otavio O Souza .
diff --git a/usr.sbin/gpioctl/gpioctl.8 b/usr.sbin/gpioctl/gpioctl.8
index c1abb5e..4db6714 100644
--- a/usr.sbin/gpioctl/gpioctl.8
+++ b/usr.sbin/gpioctl/gpioctl.8
@@ -27,7 +27,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd August 13, 2013
+.Dd November 7, 2013
 .Dt GPIOCTL 1
 .Os
 .Sh NAME
@@ -109,6 +109,8 @@ gpioctl -f /dev/gpioc0 -c 12 IN
 .El
 .Sh SEE ALSO
 .Xr gpio 4
+.Xr gpioiic 4
+.Xr gpioled 4
 .Sh HISTORY
 The
 .Nm