The fan on Radxa ROCK 5C is driven via an AO3416 MOSFET, which has a total switch-on time of 0,6us and a total switch-off time of 6us [1], meaning that the current PWM period of just 10us is too short for fine-grained fan speed control. Increase the PWM period to 60us, so that the switch-on and switch-off time of the MOSFET fall within a more reasonable ~10% of the full period, thus making lower PWM duty cycles meaningful. [1] https://www.aosmd.com/pdfs/datasheet/AO3416.pdf Fixes: 3ddf5cdb77e6 ("arm64: dts: rockchip: add Radxa ROCK 5C") Signed-off-by: FUKAUMI Naoki <naoki@xxxxxxxxx> --- Changes in v5: - Reword commit message (Alexey Charkov) Changes in v4: - none Changes in v3: - none Changes in v2: - reword commit message --- arch/arm64/boot/dts/rockchip/rk3588s-rock-5c.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/boot/dts/rockchip/rk3588s-rock-5c.dts b/arch/arm64/boot/dts/rockchip/rk3588s-rock-5c.dts index 630f026d856c..85589d1a6d3b 100644 --- a/arch/arm64/boot/dts/rockchip/rk3588s-rock-5c.dts +++ b/arch/arm64/boot/dts/rockchip/rk3588s-rock-5c.dts @@ -73,7 +73,7 @@ pwm-fan { #cooling-cells = <2>; cooling-levels = <0 64 128 192 255>; fan-supply = <&vcc_5v0>; - pwms = <&pwm3 0 10000 0>; + pwms = <&pwm3 0 60000 0>; }; pcie2x1l2_3v3: regulator-pcie2x1l2-3v3 { -- 2.43.0
