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+.. SPDX-License-Identifier: GPL-2.0+:
+
+.. index::
+   single: gpio (command)
+
+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.
+gpio status command output fields are::
+
+    <name>: <function>: <value> [x] <label>
+
+*function* can take the following values:
+
+output
+    pin configured in gpio output, *value* indicates the pin's level
+
+input
+    pin configured in gpio input, *value* indicates the pin's level
+
+func
+    pin configured in alternate function, followed by *label*
+    which shows pinmuxing label.
+
+unused
+    pin not configured
+
+*[x]* or *[ ]* indicate respectively if the gpio is used or not.
+
+*label* shows the gpio label.
+
+Parameters
+----------
+
+-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
+
+Show the GPIO status::
+
+    => gpio status
+    Bank GPIOA:
+    GPIOA1: func rgmii-0
+    GPIOA2: func rgmii-0
+    GPIOA7: func rgmii-0
+    GPIOA10: output: 0 [x] hdmi-transmitter@39.reset-gpios
+    GPIOA13: output: 1 [x] red.gpios
+
+    Bank GPIOB:
+    GPIOB0: func rgmii-0
+    GPIOB1: func rgmii-0
+    GPIOB2: func uart4-0
+    GPIOB7: input: 0 [x] mmc@58005000.cd-gpios
+    GPIOB11: func rgmii-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.