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| author | Heinrich Schuchardt <heinrich.schuchardt@canonical.com> | 2022-08-02 14:20:32 +0200 |
|---|---|---|
| committer | Heinrich Schuchardt <heinrich.schuchardt@canonical.com> | 2022-08-13 11:09:49 +0200 |
| commit | 1e120337f934b7e78d50b33fb408fd8aaa2f3b6c (patch) | |
| tree | 3f8f826ffb062b54db857e51c964bbe65f9ed874 | |
| parent | 7252f3c16af7573b748895761a9829d968a39707 (diff) | |
| download | u-boot-1e120337f934b7e78d50b33fb408fd8aaa2f3b6c.zip u-boot-1e120337f934b7e78d50b33fb408fd8aaa2f3b6c.tar.gz u-boot-1e120337f934b7e78d50b33fb408fd8aaa2f3b6c.tar.bz2 | |
doc: man-page for gpio command
Provide a man-page for the gpio command.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
| -rw-r--r-- | doc/usage/cmd/gpio.rst | 90 | ||||
| -rw-r--r-- | doc/usage/index.rst | 1 |
2 files changed, 91 insertions, 0 deletions
diff --git a/doc/usage/cmd/gpio.rst b/doc/usage/cmd/gpio.rst new file mode 100644 index 0000000..f6a5668 --- /dev/null +++ b/doc/usage/cmd/gpio.rst @@ -0,0 +1,90 @@ +.. SPDX-License-Identifier: GPL-2.0+: + +gpio command +============ + +Synopsis +-------- + +:: + + gpio <input|set|clear|toggle> <pin> + gpio read <name> <pin> + gpio status [-a] [<bank>|<pin>] + +The gpio command is used to access General Purpose Inputs/Outputs. + +gpio input +---------- + +Switch the GPIO *pin* to input mode. + +gpio set +-------- + +Switch the GPIO *pin* to output mode and set the signal to 1. + +gpio clear +---------- + +Switch the GPIO *pin* to output mode and set the signal to 0. + +gpio toggle +----------- + +Switch the GPIO *pin* to output mode and reverse the signal state. + +gpio read +--------- + +Read the signal state of the GPIO *pin* and save it in environment variable +*name*. + +gpio status +----------- + +Display the status of one or multiple GPIOs. By default only claimed GPIOs +are displayed. + +-a + Display GPIOs irrespective of being claimed. + +bank + Name of a bank of GPIOs to be displayed. + +pin + Name of a single GPIO to be displayed or manipulated. + +Examples +-------- + +Switch the status of a GPIO:: + + => gpio set a5 + gpio: pin a5 (gpio 133) value is 1 + => gpio clear a5 + gpio: pin a5 (gpio 133) value is 0 + => gpio toggle a5 + gpio: pin a5 (gpio 133) value is 1 + => gpio read myvar a5 + gpio: pin a5 (gpio 133) value is 1 + => echo $myvar + 1 + => gpio toggle a5 + gpio: pin a5 (gpio 133) value is 0 + => gpio read myvar a5 + gpio: pin a5 (gpio 133) value is 0 + => echo $myvar + 0 + +Configuration +------------- + +The *gpio* command is only available if CONFIG_CMD_GPIO=y. +The *gpio read* command is only available if CONFIG_CMD_GPIO_READ=y. + +Return value +------------ + +If the command succeds the return value $? is set to 0. If an error occurs, the +return value $? is set to 1. diff --git a/doc/usage/index.rst b/doc/usage/index.rst index 2ba8733..28f9683 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -45,6 +45,7 @@ Shell commands cmd/fatload cmd/fdt cmd/for + cmd/gpio cmd/load cmd/loadm cmd/loady |