Re: [PATCH v3] arm64: dts: rockchip: add thermal fan control to rockpro64

[Daniel Lezcano]

On 30/07/2021 17:17, Peter Geis wrote:
> The rockpro64 had a fan node since
> commit 5882d65c1691 ("arm64: dts: rockchip: Add PWM fan for RockPro64")
> however it was never tied into the thermal driver for automatic control.
> 
> Add the links to the thermal node to permit the kernel to handle this
> automatically.
> Borrowed from the (rk3399-khadas-edge.dtsi).
> 
> Signed-off-by: Peter Geis <pgwipeout@xxxxxxxxx>
> ---
> 
> Changelog:
> v3:
> Removed the gpu nodes to prevent in-fighting (thanks Robin!)
> 
> v2:
> Adjusted fan setpoints for less noise
> 
>  .../boot/dts/rockchip/rk3399-rockpro64.dtsi   | 29 +++++++++++++++++++
>  1 file changed, 29 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/rockchip/rk3399-rockpro64.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-rockpro64.dtsi
> index 6bff8db7d33e..83db4ca67334 100644
> --- a/arch/arm64/boot/dts/rockchip/rk3399-rockpro64.dtsi
> +++ b/arch/arm64/boot/dts/rockchip/rk3399-rockpro64.dtsi
> @@ -69,6 +69,7 @@ diy_led: led-1 {
>  
>  	fan: pwm-fan {
>  		compatible = "pwm-fan";
> +		cooling-levels = <0 100 150 200 255>;
>  		#cooling-cells = <2>;
>  		fan-supply = <&vcc12v_dcin>;
>  		pwms = <&pwm1 0 50000 0>;
> @@ -245,6 +246,34 @@ &cpu_b1 {
>  	cpu-supply = <&vdd_cpu_b>;
>  };
>  
> +&cpu_thermal {
> +	trips {
> +		cpu_warm: cpu_warm {
> +			temperature = <55000>;
> +			hysteresis = <2000>;
> +			type = "active";
> +		};
> +
> +		cpu_hot: cpu_hot {
> +			temperature = <65000>;
> +			hysteresis = <2000>;
> +			type = "active";
> +		};
> +	};
> +

Why two trip points ?

Why not one functioning temperature and no lower / upper limits for the
cooling maps ?


> +	cooling-maps {
> +		map2 {
> +			trip = <&cpu_warm>;
> +			cooling-device = <&fan THERMAL_NO_LIMIT 1>;
> +		};
> +
> +		map3 {
> +			trip = <&cpu_hot>;
> +			cooling-device = <&fan 2 THERMAL_NO_LIMIT>;
> +		};
> +	};
> +};
> +
>  &emmc_phy {
>  	status = "okay";
>  };
> 


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