Re: [PATCH 4/8] hwmon: Add Apple Silicon SMC hwmon driver

[Lee Jones <lee@kernel.org>]

On Tue, 19 Aug 2025, James Calligeros wrote:

> The System Management Controller on Apple Silicon devices is responsible
> for integrating and exposing the data reported by the vast array of
> hardware monitoring sensors present on these devices. It is also
> responsible for fan control, and allows users to manually set fan
> speeds if they so desire. Add a hwmon driver to expose current,
> power, temperature, and voltage monitoring sensors, as well as
> fan speed monitoring and control via the SMC on Apple Silicon devices.
> 
> The SMC firmware has no consistency between devices, even when they
> share an SoC. The FourCC keys used to access sensors are almost
> random. An M1 Mac mini will have different FourCCs for its CPU core
> temperature sensors to an M1 MacBook Pro, for example. For this
> reason, the valid sensors for a given device are specified in a
> child of the SMC Devicetree node. The driver uses this information
> to determine which sensors to make available at runtime.
> 
> Co-developed-by: Janne Grunau <j@jannau.net>
> Signed-off-by: Janne Grunau <j@jannau.net>
> Signed-off-by: James Calligeros <jcalligeros99@gmail.com>
> ---
>  MAINTAINERS                  |   2 +
>  drivers/hwmon/Kconfig        |  12 +
>  drivers/hwmon/Makefile       |   1 +
>  drivers/hwmon/macsmc_hwmon.c | 858 +++++++++++++++++++++++++
>  drivers/mfd/macsmc.c         |   1 +

And here.  And everywhere else.

>  5 files changed, 874 insertions(+)

-- 
Lee Jones [李琼斯]