Re: [PATCH v6] hwmon: add driver for ARCTIC Fan Controller
From: Guenter Roeck
Date: Wed Apr 01 2026 - 11:50:13 EST
Hi,
On Wed, Apr 01, 2026 at 07:25:54PM +0800, 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>
> ---
Looks like the patch is corrupted.
Applying: hwmon: add driver for ARCTIC Fan Controller
error: corrupt patch at line 587
error: could not build fake ancestor
Patch failed at 0001 hwmon: add driver for ARCTIC Fan Controller
I can not figure out what is wrong, but both git and patch report that it is
corrupted. Please fix and resend.
Thanks,
Guenter