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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250819123902.GD7508@google.com>
Date: Tue, 19 Aug 2025 13:39:02 +0100
From: Lee Jones <lee@...nel.org>
To: James Calligeros <jcalligeros99@...il.com>
Cc: Sven Peter <sven@...nel.org>, Janne Grunau <j@...nau.net>,
	Alyssa Rosenzweig <alyssa@...enzweig.io>,
	Neal Gompa <neal@...pa.dev>, Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>,
	Alexandre Belloni <alexandre.belloni@...tlin.com>,
	Jean Delvare <jdelvare@...e.com>,
	Guenter Roeck <linux@...ck-us.net>,
	Dmitry Torokhov <dmitry.torokhov@...il.com>, asahi@...ts.linux.dev,
	linux-arm-kernel@...ts.infradead.org, devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-rtc@...r.kernel.org,
	linux-hwmon@...r.kernel.org, linux-input@...r.kernel.org
Subject: Re: [PATCH 4/8] hwmon: Add Apple Silicon SMC hwmon driver

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@...nau.net>
> Signed-off-by: Janne Grunau <j@...nau.net>
> Signed-off-by: James Calligeros <jcalligeros99@...il.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]