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.. dtcompatible:: st,stm32-lptim
.. _dtbinding_st_stm32_lptim:

st,stm32-lptim
##############

Vendor: :ref:`STMicroelectronics <dt_vendor_st>`

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



.. code-block:: none

   STM32 lptim : low power timer
   The lptim node to be used for counting ticks during lowpower modes
   must be named stm32_lp_tick_source in the DTS, as follows:
   stm32_lp_tick_source: &lptim1 {
    status = "okay";
   }

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

         * - ``st,prescaler``
           - ``int``
           - .. code-block:: none

                Clock divider at the input of the lptimer clock, default reset value is 'not divided'.

                Prescaler allows to achieve higher LPTIM timeout (up to 256s when lptim clocked by LSE)
                and consequently higher core sleep durations, but impacts the tick precision.
                To be used with caution.
                CONFIG_SYS_CLOCK_TICKS_PER_SEC could be used to tune tick duration and gain precision,
                at kernel timing granularity cost.

                For example, when LPTIM is clocked by the LSE (32768Hz) and st,prescaler = <32>:
                LPTIM global timeout is 64 seconds with an increment of 0.97 ms.
                Using CONFIG_SYS_CLOCK_TICKS_PER_SEC = 4096, tick = 0.24 ms, LPTIM precision is 4 ticks.
                Using CONFIG_SYS_CLOCK_TICKS_PER_SEC = 1024, tick = 0.97 ms, LPTIM precision is 1 ticks.



             Default value: ``1``

             Legal values: ``1``, ``2``, ``4``, ``8``, ``16``, ``32``, ``64``, ``128``

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

                Name of each reset




   .. 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 "st,stm32-lptim" compatible.

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

         * - Name
           - Type
           - Details

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

                register space


             This property is **required**.

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

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

                Clock gate information


             This property is **required**.

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

                indicates the operational status of a device


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

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

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

                compatible strings


             This property is **required**.

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

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

                name of each register space


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

                interrupts for device


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

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

                extended interrupt specifier for device


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

                name of each interrupt


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

                phandle to interrupt controller node


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

                Human readable string describing the device (used as device_get_binding() argument)



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

             This property is **deprecated**.

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

                name of each clock


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

                number of address cells in reg property


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

                number of size cells in reg property


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

                DMA channels specifiers


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

                Provided names of DMA channel specifiers


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

                IO channels specifiers


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

                Provided names of IO channel specifiers


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

                mailbox / IPM channels specifiers


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

                Provided names of mailbox / IPM channel specifiers


         * - ``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.



         * - ``power-domain``
           - ``phandle``
           - .. code-block:: none


                Power domain the device belongs to.

                The device will be notified when the power domain it belongs to is either
                suspended or resumed.



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

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