[PATCH] arm64: dts: rockchip: pwm-fan overlay for NanoPC-T6

[Alexey Charkov]

Hi Hugh,

On Mon, Oct 27, 2025 at 1:09 PM Hugh Cole-Baker <sigmaris at gmail.com> wrote:
>
> FriendlyELEC offers an optional heatsink and fan addon for the NanoPC-T6
> and T6 LTS. Add an overlay which can be applied if the fan is fitted and
> configures the fan as an active cooling device for the SoC package.
>
> Signed-off-by: Hugh Cole-Baker <sigmaris at gmail.com>
> ---
> FriendlyELEC heatsink with fan addon:
> https://www.friendlyelec.com/index.php?route=product/product&product_id=305
> Vendor DT with trip points and PWM duty cycle values:
> https://github.com/friendlyarm/kernel-rockchip/blob/4944602540b62f5aad139fe602a76cf7c3176128/arch/arm64/boot/dts/rockchip/rk3588-nanopi6-rev01.dts#L75-L90

Is there any downside to enabling this unconditionally in the board
.dts? Overlays require more user configuration, and not all
bootloaders support them directly (e.g. systemd-boot users would
struggle). Compiling with overlays enabled also makes .dtb's a lot
larger due to added symbols information.

Best regards,
Alexey