[PATCH v2 00/11] mfd: macsmc: add rtc, hwmon and hid subdevices

Guenter Roeck linux at roeck-us.net
Wed Aug 27 06:47:52 PDT 2025


On 8/27/25 04:22, James Calligeros wrote:
> Hi all,
> 
> This series adds support for the remaining SMC subdevices. These are the
> RTC, hwmon, and HID devices. They are being submitted together as the RTC
> and hwmon drivers both require changes to the SMC DT schema.
> 
> The RTC driver is responsible for getting and setting the system clock,
> and requires an NVMEM cell. This series replaces Sven's original RTC driver
> submission [1].
> 
> The hwmon function is an interesting one. While each Apple Silicon device
> exposes pretty similar sets of sensors, these all seem to be paired to
> different SMC keys in the firmware interface. This is true even when the
> sensors are on the SoC. For example, an M1 MacBook Pro will use different
> keys to access the LITTLE core temperature sensors to an M1 Mac mini. This
> necessitates describing which keys correspond to which sensors for each
> device individually, and populating the hwmon structs at runtime. We do
> this with a node in the device tree. This series includes only the keys
> for sensors which we know to be common to all devices. The SMC is also
> responsible for monitoring and controlling fan speeds on systems with fans,
> which we expose via the hwmon driver.
> 
> The SMC also handles the hardware power button and lid switch. Power
> button presses and lid opening/closing are emitted as HID events, so we
> add a HID subdevice to handle them.
> 
> Note that this series is based on a branch with three additional commits
> applied to add the parent SMC nodes to the relevant Devicetrees. This
> was done to silence build errors. The series applies cleanly to 6.17-rc1.
> 
> Regards,
> 
> James
> 
> [1] https://lore.kernel.org/asahi/CAEg-Je84XxLWH7vznQmPRfjf6GxWOu75ZetwN7AdseAwfMLLrQ@mail.gmail.com/T/#t
> 
> Signed-off-by: James Calligeros <jcalligeros99 at gmail.com>
> ---
> Changes in v2:
> - Added Rob's R-b tag to RTC DT binding
> - Removed redundant nesting from hwmon DT binding
> - Dedpulicated property definitions in hwmon DT schema
> - Made label a required property for hwmon DT nodes
> - Clarified semantics in hwmon DT schema definitions
> - Split mfd tree changes into separate commits
> - Fixed numerous style errors in hwmon driver
> - Addressed Guenter's initial feedback on the hwmon driver

Don't you think that is a bit useless ? You might as well say "Addressed
feedback comments" and be done with the change log.

Guenter




More information about the linux-arm-kernel mailing list