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.. dtcompatible:: gpio-qdec
.. _dtbinding_gpio_qdec:

gpio-qdec
#########

Vendor: :ref:`Generic or vendor-independent <dt_no_vendor>`

.. note::

   An implementation of a driver matching this compatible is available in
   :zephyr_file:`drivers/input/input_gpio_qdec.c`.

Description
***********



.. code-block:: none

   GPIO based QDEC input device

   Implement an input device generating relative axis event reports for a rotary
   encoder connected to two GPIOs. The driver is normally idling until it sees a
   transition on any of the encoder signal lines, then switches to polling mode
   and samples the two signal lines periodically to track the encoder position,
   and goes back to idling after the specified timeout.

   Example configuration:

   #include <zephyr/dt-bindings/input/input-event-codes.h>

   qdec {
           compatible = "gpio-qdec";
           gpios = <&gpio0 14 (GPIO_PULL_UP | GPIO_ACTIVE_HIGH)>,
                   <&gpio0 13 (GPIO_PULL_UP | GPIO_ACTIVE_HIGH)>;
           steps-per-period = <4>;
           zephyr,axis = <INPUT_REL_WHEEL>;
           sample-time-us = <2000>;
           idle-timeout-ms = <200>;
   };

Properties
**********

.. tabs::

   .. group-tab:: Node specific properties

      Properties not inherited from the base binding file.

      .. list-table::
         :widths: 1 1 4
         :header-rows: 1

         * - Name
           - Type
           - Details

         * - ``gpios``
           - ``phandle-array``
           - .. code-block:: none

                GPIO for the A and B encoder signals.



             This property is **required**.

         * - ``led-gpios``
           - ``phandle-array``
           - .. code-block:: none

                GPIOs for LED or other components needed for sensing the AB signals.



         * - ``led-pre-us``
           - ``int``
           - .. code-block:: none

                Time between enabling the led-gpios output pins and reading the encoder
                state on the input pins, meant to give the state detector (such a
                phototransistor) time to settle to right state. Required if led-gpios and
                idle-poll-time-us are specified, can be explicitly set to 0 for no delay.



         * - ``steps-per-period``
           - ``int``
           - .. code-block:: none

                How many steps to count before reporting an input event.



             This property is **required**.

         * - ``zephyr,axis``
           - ``int``
           - .. code-block:: none

                The input code for the axis to report for the device, typically any of
                INPUT_REL_*.



             This property is **required**.

         * - ``sample-time-us``
           - ``int``
           - .. code-block:: none

                How often to sample the A and B signal lines when tracking the encoder
                movement.



             This property is **required**.

         * - ``idle-poll-time-us``
           - ``int``
           - .. code-block:: none

                How often to sample the A and B signal while idling. If unset then the
                driver will use the GPIO interrupt to exit idle state, and any GPIO
                specified in led-gpios will be enabled all the time. If non zero, then
                the driver will poll every idle-poll-time-us microseconds while idle, and
                only activate led-gpios before sampling the encoder state.



         * - ``idle-timeout-ms``
           - ``int``
           - .. code-block:: none

                Timeout for the last detected transition before stopping the sampling
                timer and going back to idle state.



             This property is **required**.



   .. group-tab:: Deprecated node specific properties

      Deprecated properties not inherited from the base binding file.

      (None)

   .. group-tab:: Base properties

      Properties inherited from the base binding file, which defines
      common properties that may be set on many nodes. Not all of these
      may apply to the "gpio-qdec" compatible.

      .. list-table::
         :widths: 1 1 4
         :header-rows: 1

         * - Name
           - Type
           - Details

         * - ``status``
           - ``string``
           - .. code-block:: none

                Indicates the operational status of the hardware or other
                resource that the node represents. In particular:

                  - "okay" means the resource is operational and, for example,
                    can be used by device drivers
                  - "disabled" means the resource is not operational and the system
                    should treat it as if it is not present

                For details, see "2.3.4 status" in Devicetree Specification v0.4.



             Legal values: ``'ok'``, ``'okay'``, ``'disabled'``, ``'reserved'``, ``'fail'``, ``'fail-sss'``

             See :ref:`zephyr:dt-important-props` for more information.

         * - ``compatible``
           - ``string-array``
           - .. code-block:: none

                This property is a list of strings that essentially define what
                type of hardware or other resource this devicetree node
                represents. Each device driver checks for specific compatible
                property values to find the devicetree nodes that represent
                resources that the driver should manage.

                The recommended format is "vendor,device", The "vendor" part is
                an abbreviated name of the vendor. The "device" is usually from
                the datasheet.

                The compatible property can have multiple values, ordered from
                most- to least-specific. Having additional values is useful when the
                device is a specific instance of a more general family, to allow the
                system to match the most specific driver available.

                For details, see "2.3.1 compatible" in Devicetree Specification v0.4.



             This property is **required**.

             See :ref:`zephyr:dt-important-props` for more information.

         * - ``reg``
           - ``array``
           - .. code-block:: none

                Information used to address the device. The value is specific to
                the device (i.e. is different depending on the compatible
                property).

                The "reg" property is typically a sequence of (address, length) pairs.
                Each pair is called a "register block". Values are
                conventionally written in hex.

                For details, see "2.3.6 reg" in Devicetree Specification v0.4.



             See :ref:`zephyr:dt-important-props` for more information.

         * - ``reg-names``
           - ``string-array``
           - .. code-block:: none

                Optional names given to each register block in the "reg" property.
                For example:

                  / {
                       soc {
                           #address-cells = <1>;
                           #size-cells = <1>;

                           uart@1000 {
                               reg = <0x1000 0x2000>, <0x3000 0x4000>;
                               reg-names = "foo", "bar";
                           };
                       };
                  };

                The uart@1000 node has two register blocks:

                  - one with base address 0x1000, size 0x2000, and name "foo"
                  - another with base address 0x3000, size 0x4000, and name "bar"



         * - ``interrupts``
           - ``array``
           - .. code-block:: none

                Information about interrupts generated by the device, encoded as an array
                of one or more interrupt specifiers. The format of the data in this property
                varies by where the device appears in the interrupt tree. Devices with the same
                "interrupt-parent" will use the same format in their interrupts properties.

                For details, see "2.4 Interrupts and Interrupt Mapping" in
                Devicetree Specification v0.4.



             See :ref:`zephyr:dt-important-props` for more information.

         * - ``interrupts-extended``
           - ``compound``
           - .. code-block:: none

                Extended interrupt specifier for device, used as an alternative to
                the "interrupts" property.

                For details, see "2.4 Interrupts and Interrupt Mapping" in
                Devicetree Specification v0.4.



         * - ``interrupt-names``
           - ``string-array``
           - .. code-block:: none

                Optional names given to each interrupt generated by a device.
                The interrupts themselves are defined in either "interrupts" or
                "interrupts-extended" properties.

                For details, see "2.4 Interrupts and Interrupt Mapping" in
                Devicetree Specification v0.4.



         * - ``interrupt-parent``
           - ``phandle``
           - .. code-block:: none

                If present, this refers to the node which handles interrupts generated
                by this device.

                For details, see "2.4 Interrupts and Interrupt Mapping" in
                Devicetree Specification v0.4.



         * - ``label``
           - ``string``
           - .. code-block:: none

                Human readable string describing the device. Use of this property is
                deprecated except as needed on a case-by-case basis.

                For details, see "4.1.2 Miscellaneous Properties" in Devicetree
                Specification v0.4.



             See :ref:`zephyr:dt-important-props` for more information.

         * - ``clocks``
           - ``phandle-array``
           - .. code-block:: none

                Information about the device's clock providers. In general, this property
                should follow conventions established in the dt-schema binding:

                  https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/clock/clock.yaml



         * - ``clock-names``
           - ``string-array``
           - .. code-block:: none

                Optional names given to each clock provider in the "clocks" property.



         * - ``#address-cells``
           - ``int``
           - .. code-block:: none

                This property encodes the number of <u32> cells used by address fields
                in "reg" properties in this node's children.

                For details, see "2.3.5 #address-cells and #size-cells" in Devicetree
                Specification v0.4.



         * - ``#size-cells``
           - ``int``
           - .. code-block:: none

                This property encodes the number of <u32> cells used by size fields in
                "reg" properties in this node's children.

                For details, see "2.3.5 #address-cells and #size-cells" in Devicetree
                Specification v0.4.



         * - ``dmas``
           - ``phandle-array``
           - .. code-block:: none

                DMA channel specifiers relevant to the device.



         * - ``dma-names``
           - ``string-array``
           - .. code-block:: none

                Optional names given to the DMA channel specifiers in the "dmas" property.



         * - ``io-channels``
           - ``phandle-array``
           - .. code-block:: none

                IO channel specifiers relevant to the device.



         * - ``io-channel-names``
           - ``string-array``
           - .. code-block:: none

                Optional names given to the IO channel specifiers in the "io-channels" property.



         * - ``mboxes``
           - ``phandle-array``
           - .. code-block:: none

                Mailbox / IPM channel specifiers relevant to the device.



         * - ``mbox-names``
           - ``string-array``
           - .. code-block:: none

                Optional names given to the mbox specifiers in the "mboxes" property.



         * - ``power-domains``
           - ``phandle-array``
           - .. code-block:: none

                Power domain specifiers relevant to the device.



         * - ``power-domain-names``
           - ``string-array``
           - .. code-block:: none

                Optional names given to the power domain specifiers in the "power-domains" property.



         * - ``#power-domain-cells``
           - ``int``
           - .. code-block:: none

                Number of cells in power-domains property



         * - ``zephyr,deferred-init``
           - ``boolean``
           - .. code-block:: none

                Do not initialize device automatically on boot. Device should be manually
                initialized using device_init().



         * - ``wakeup-source``
           - ``boolean``
           - .. code-block:: none

                Property to identify that a device can be used as wake up source.

                When this property is provided a specific flag is set into the
                device that tells the system that the device is capable of
                wake up the system.

                Wake up capable devices are disabled (interruptions will not wake up
                the system) by default but they can be enabled at runtime if necessary.



         * - ``zephyr,pm-device-runtime-auto``
           - ``boolean``
           - .. code-block:: none

                Automatically configure the device for runtime power management after the
                init function runs.



         * - ``zephyr,disabling-power-states``
           - ``phandles``
           - .. code-block:: none

                List of power states that will disable this device power.