Re: [PATCH v3] drm/xe/hwmon: document DG2 fan speed reporting quirk

From: Raag Jadav

Date: Sat May 30 2026 - 03:13:19 EST


On Sat, May 30, 2026 at 01:24:49AM +0800, Zhan Wei wrote:
> On DG2 the driver always shows two fan channels, because the
> FSC_READ_NUM_FANS command does not work on some cards. OEMs decide how
> the fans map to tach channels, so two fans can share one tach line.
> When that happens, the second channel reads 0 RPM even though the fan
> is spinning.
>
> Note this on the fan2_input ABI entry so the steady 0 RPM is not
> mistaken for a driver bug.

Fixes: 28f79ac609de ("drm/xe/hwmon: expose fan speed")

> Signed-off-by: Zhan Wei <zhanwei919@xxxxxxxxx>

Reviewed-by: Raag Jadav <raag.jadav@xxxxxxxxx>