Re: [PATCH 0/3] platform: arm64: thinkpad-t14s-ec: new driver

[Neil Armstrong <neil.armstrong@linaro.org>]

On 31/08/2025 23:28, Sebastian Reichel wrote:
> Introduce driver for the ThinkPad T14s Gen6 Snapdragon EC. In theory
> it seems to be compatible with the ThinkPad ACPI driver, but these
> devices are booted with device tree. As the name implies, the existing
> ThinkPad ACPI driver only supports the ACPI interface. Looking at
> the implementation, the ACPI DSDT contains many mapping functions
> to translate the low level I2C messages into the interface used by
> the ThinkPad ACPI driver. Adding DT support to the ThinkPad ACPI driver
> would require adding all those translation functions, which would add
> more or less the same amount of code as writing a separate driver using
> the low level interface directly. I don't think it's sensible to make
> the existing ACPI driver even more complicated, so I went for a separate
> driver.
> 
> I managed to get system LEDs, audio LEDs, extra keys and the keyboard
> backlight control working. The EC also seems to be used for some thermal
> bits, which I haven't looked into deeply. As far as I understand most
> thermal and fan control is handled by a different controller
> (0x36@i2c5) anyways.
> 
> Apart from that the EC is involved in proper system suspend, which
> is something I do not yet understand (I don't have any documentation
> apart from the dis-assembled DSDT and existing ACPI driver). Right
> now I disabled wake capabilities for the IRQ, since it would wake
> up the system when closing the LID. Hopefully a way to mask specific
> events will be found in the future.
> 
> Signed-off-by: Sebastian Reichel <sre@kernel.org>
> ---
> Sebastian Reichel (3):
>        dt-bindings: platform: Add Lenovo Thinkpad T14s EC
>        platform: arm64: thinkpad-t14s-ec: new driver
>        arm64: dts: qcom: x1e80100-t14s: add EC
> 
>   .../bindings/platform/lenovo,thinkpad-t14s-ec.yaml |  49 ++
>   MAINTAINERS                                        |   6 +
>   .../dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi    |  23 +
>   drivers/platform/arm64/Kconfig                     |  20 +
>   drivers/platform/arm64/Makefile                    |   1 +
>   drivers/platform/arm64/lenovo-thinkpad-t14s.c      | 597 +++++++++++++++++++++
>   6 files changed, 696 insertions(+)
> ---
> base-commit: c8bc81a52d5a2ac2e4b257ae123677cf94112755
> change-id: 20250831-thinkpad-t14s-ec-ddeb23dbdafb
> 
> Best regards,

Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on Thinkpad T14S OLED

All worked :-)

Thanks !

Neil