diff options
Diffstat (limited to 'share/man/man4')
| -rw-r--r-- | share/man/man4/gpio.4 | 38 |
1 files changed, 20 insertions, 18 deletions
diff --git a/share/man/man4/gpio.4 b/share/man/man4/gpio.4 index 1d2eadcb525..bf99bd0bc3f 100644 --- a/share/man/man4/gpio.4 +++ b/share/man/man4/gpio.4 @@ -1,4 +1,4 @@ -.\" $OpenBSD: gpio.4,v 1.1 2004/06/03 18:41:29 grange Exp $ +.\" $OpenBSD: gpio.4,v 1.2 2004/06/03 23:53:57 jmc Exp $ .\" .\" Copyright (c) 2004 Alexander Yurchenko <grange@openbsd.org> .\" @@ -36,19 +36,19 @@ controller and provides a uniform programming interface to its pins. .Pp Each .Tn GPIO -controller with attached +controller with an attached .Nm -device has associated device file under the +device has an associated device file under the .Pa /dev -directory, e.g. +directory, e.g.\& .Pa /dev/gpio0 . Access from userland is performed through .Xr ioctl 2 calls on these devices. .Sh IOCTL INTERFACE -The following structures and constants are defined in -.Aq Pa sys/gpio.h -header file. +The following structures and constants are defined in the +.Aq Pa sys/gpio.h +header file: .Pp .Bl -tag -width XXXX -compact .It Dv GPIOINFO (struct gpio_info) @@ -64,7 +64,7 @@ struct gpio_info { .Ed .Pp .It Dv GPIOPINREAD (struct gpio_pin_op) -Returns input pin value in the +Returns the input pin value in the .Fa gpio_pin_op structure: .Bd -literal @@ -79,22 +79,22 @@ The field must be set before calling. .Pp .It Dv GPIOPINWRITE (struct gpio_pin_op) -Writes output value to the pin. -Value set in the +Writes the output value to the pin. +The value set in the .Fa gp_value field must be either .Dv GPIO_PIN_LOW (logical 0) or .Dv GPIO_PIN_HIGH (logical 1). -On return +On return, the .Fa gp_value -field contains old pin state. +field contains the old pin state. .Pp .It Dv GPIOPINTOGGLE (struct gpio_pin_op) -Toggles pin output value, i.e. changes it to the opposite. +Toggles the pin output value, i.e. changes it to the opposite. .Fa gp_value -field is ignored and on return contains old pin state. +field is ignored and on return contains the old pin state. .Pp .It Dv GPIOPINCTL (struct gpio_pin_ctl) Changes pin configuration flags with the new ones provided in the @@ -108,6 +108,7 @@ struct gpio_pin_ctl { }; .Ed .Pp +The .Fa gp_flags field is a combination of the following flags: .Pp @@ -131,11 +132,11 @@ internal pull-up enabled Note that the .Tn GPIO controller -may not support all these flags. +may not support all of these flags. On return the .Fa gp_caps field contains flags that are supported. -If no flags specified pin configuration stays unchanged. +If no flags are specified, the pin configuration stays unchanged. .El .Sh FILES .Bl -tag -width "/dev/gpiou" -compact @@ -143,11 +144,12 @@ If no flags specified pin configuration stays unchanged. GPIO device unit .Ar u file. +.El .Sh SEE ALSO .Xr ioctl 2 , .Xr gscpcib 4 , -.Xr nsclpcsio 4 -.Xr gpioctl 8 , +.Xr nsclpcsio 4 , +.Xr gpioctl 8 .Sh HISTORY The .Nm |