Re: [PATCH 2/2] Documentation: wmi: alienware-wmi: Add GPIO control documentation

[Armin Wolf <W_Armin@gmx.de>]

Am 23.04.25 um 09:49 schrieb Kurt Borja:

> Add documentation for the GPIO control methods.
>
> Signed-off-by: Kurt Borja <kuurtb@gmail.com>
> ---
>   Documentation/wmi/devices/alienware-wmi.rst | 85 +++++++++++++++++++++++++++--
>   1 file changed, 81 insertions(+), 4 deletions(-)
>
> diff --git a/Documentation/wmi/devices/alienware-wmi.rst b/Documentation/wmi/devices/alienware-wmi.rst
> index 79238051b18bc5de9b502325017cd5c5fcf41748..8751199834b8e2a3a4abf2b735e4ac6067d93c6d 100644
> --- a/Documentation/wmi/devices/alienware-wmi.rst
> +++ b/Documentation/wmi/devices/alienware-wmi.rst
> @@ -231,6 +231,77 @@ WMI method MemoryOCControl([in] uint32 arg2, [out] uint32 argr)
>   AWCC supports memory overclocking, but this method is very intricate and has
>   not been deciphered yet.
>   
> +GPIO control Methods
> +====================
> +
> +Alienware and Dell G Series devices with the AWCC interface, usually have an

Hi,

please remove the comma.

> +embedded STM32 RGB lighting controller with USB/HID capabilities. It's vendor ID
> +is `187c` while it's product ID may vary from model to model.
> +
> +The control of two GPIO pins of this MCU is exposed as WMI methods for debugging
> +purposes.
> +
> ++--------------+--------------------------------------------------------------+
> +| Pin          | Description                                                  |
> ++==============+==============================================================+
> +| 0            | Device Firmware Update (DFU) mode pin.                       |
> +|              |                                                              |
> +|              | **HIGH**: Enables DFU mode on next MCU boot.                 |
> +|              |                                                              |
> +|              | **LOW**: Disables DFU mode on next MCU boot. (default)       |
> ++--------------+--------------------------------------------------------------+
> +| 1            | Negative Reset (NRST) pin.                                   |
> +|              |                                                              |
> +|              | **HIGH**: Turn on MCU. (default)                             |
> +|              |                                                              |
> +|              | **LOW**: Turn off MCU.                                       |
> ++--------------+--------------------------------------------------------------+
> +
> +See :ref:`acknowledgements` for more information on this MCU.
> +
> +.. warning::
> +   The following methods are only exposed to DebugFS if the ``gpio_debug``
> +   unsafe module parameter is set, as you could end up bricking the MCU.
> +
> +WMI method FWUpdateGPIOtoggle([in] uint32 arg2, [out] uint32 argr)
> +------------------------------------------------------------------
> +
> ++--------------------+------------------------------------+--------------------+
> +| Operation (Byte 0) | Description                        | Arguments          |
> ++====================+====================================+====================+
> +| 0x00               | Set the Device Firmware Update     | - Byte 1: Pin      |
> +|                    | (DFU) pin status.                  |   status           |
> ++--------------------+------------------------------------+--------------------+
> +| 0x01               | Set the Negative Reset (NRST) pin  | - Byte 1: Pin      |
> +|                    | status.                            |   status           |
> ++--------------------+------------------------------------+--------------------+

Maybe it would be better if you just explain that the operation byte selects the GPIO pin to toggle.

> +
> +WMI method ReadTotalofGPIOs([out] uint32 argr)
> +----------------------------------------------
> +
> ++--------------------+------------------------------------+--------------------+
> +| Operation (Byte 0) | Description                        | Arguments          |
> ++====================+====================================+====================+
> +| 0x00               | Get the total number of GPIOs.     | - None             |
> ++--------------------+------------------------------------+--------------------+
> +
> +WMI method ReadGPIOpPinStatus([in] uint32 arg2, [out] uint32 argr)
> +------------------------------------------------------------------
> +
> ++--------------------+------------------------------------+--------------------+
> +| Operation (Byte 0) | Description                        | Arguments          |
> ++====================+====================================+====================+
> +| 0x00               | Get the Device Firmware Update     | - None             |
> +|                    | (DFU) pin status.                  |                    |
> ++--------------------+------------------------------------+--------------------+
> +| 0x01               | Get the Negative Reset (NRST) pin  | - None             |
> +|                    | status.                            |                    |
> ++--------------------+------------------------------------+--------------------+

Same as above.

Thanks,
Armin Wolf

> +
> +.. warning::
> +   There known firmware bug in some laptops where reading the status of a pin
> +   also flips it.
> +
>   Other information Methods
>   =========================
>   
> @@ -239,10 +310,16 @@ WMI method ReadChassisColor([out] uint32 argr)
>   
>   Returns the chassis color internal ID.
>   
> +.. _acknowledgements:
> +
>   Acknowledgements
>   ================
>   
> -Kudos to `AlexIII <https://github.com/AlexIII/tcc-g15>`_ and
> -`T-Troll <https://github.com/T-Troll/alienfx-tools/>`_ for documenting and
> -testing some of this device's functionality, making it possible to generalize
> -this driver.
> +Kudos to
> +
> +* `AlexIII <https://github.com/AlexIII/tcc-g15>`_
> +* `T-Troll <https://github.com/T-Troll/alienfx-tools/>`_
> +* `Gabriel Marcano <https://gabriel.marcanobrady.family/blog/2024/12/16/dell-g5-5505-se-acpi-or-figuring-out-how-to-reset-the-rgb-controller/>`_
> +
> +for documenting and testing some of this device's functionality, making it
> +possible to generalize this driver.
>