Re: [PATCH v7] hwmon: add driver for ARCTIC Fan Controller

[Guenter Roeck]

Hi,

On 4/23/26 02:15, Aureo Serrano de Souza wrote:
> Add hwmon driver for the ARCTIC Fan Controller, a USB HID device
> (VID 0x3904, PID 0xF001) with 10 fan channels. Exposes fan speed in
> RPM (read-only) and PWM duty cycle (0-255, read/write) via sysfs.
>
> The device pushes IN reports at ~1 Hz containing RPM readings. PWM is
> set via OUT reports; the device applies the new duty cycle and sends
> back a 2-byte ACK (Report ID 0x02). The driver waits up to 1 s for
> the ACK using a completion. Measured device latency: max ~563 ms over
> 500 iterations. PWM control is manual-only: the device never changes
> duty cycle autonomously.
>
> raw_event() may run in hardirq context, so fan_rpm[] is protected by
> a spinlock with irq-save. pwm_duty[] is also protected by this spinlock
> because reset_resume() clears it outside the hwmon core lock. The OUT
> report buffer is built and write_pending is armed under the same lock so
> that no reset_resume() can race with the pwm_duty[] snapshot. priv->buf
> is exclusively accessed by write(), which the hwmon core serializes.
>
> Signed-off-by: Aureo Serrano de Souza <aureo.serrano@xxxxxxxxx>

I don't know why, but Sashiko failed to apply this patch.

https://sashiko.dev/#/patchset/20260423091551.15080-1-aureo.serrano%40arctic.de

Please rebase on top of mainline or linux-next and resend.

Thanks,
Guenter