arm64: dts: rockchip: add fan on rk3399-sapphire board

The Sapphire board has a 12V fan. So, adding it to the DTS.
There is no power supply directly connected, it needs the baseboard to
work.
If the board is used standalone then a hardware modification is needed.
On the Sapphire board there is an unpopulated resistor to connect it to
VBUS_TYPEC, which is usually 5V (too low) and can range up to 20V
(too high).
I tested it for a week connected to VCC_SYS which is 8.4V and proved to
be more than enough for the required cooling needs. This is the
connection described in the comment.

Signed-off-by: Vicente Bergas <vicencb@gmail.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

diff --git a/arch/arm64/boot/dts/rockchip/rk3399-sapphire.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-sapphire.dtsi
index 5421e23760c35c60d45e0519f1cb9203abf7db83..90d813bdabde9e042eb70dec7b8fa0b7e3da6d0f 100644 (file)
--- a/arch/arm64/boot/dts/rockchip/rk3399-sapphire.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3399-sapphire.dtsi
@@ -66,6 +66,19 @@
                regulator-max-microvolt = <12000000>;
        };
 
+       /*
+        * The fan power supply comes from the baseboard.
+        * For the standalone Sapphire one option is to connect a wire
+        * from  R90030 DNP R0805 pin2  to  C90002 10uF C0805 pin1 (vcc_sys).
+        */
+       fan0: gpio-fan {
+               #cooling-cells = <2>;
+               compatible = "gpio-fan";
+               gpio-fan,speed-map = <0 0 3000 1>;
+               gpios = <&gpio1 RK_PC2 GPIO_ACTIVE_HIGH>;
+               status = "okay";
+       };
+
        keys: gpio-keys {
                compatible = "gpio-keys";
                autorepeat;
@@ -183,6 +196,24 @@
        cpu-supply = <&vdd_cpu_b>;
 };
 
+&cpu_thermal {
+       trips {
+               cpu_hot: cpu_hot {
+                       hysteresis = <10000>;
+                       temperature = <55000>;
+                       type = "active";
+               };
+       };
+
+       cooling-maps {
+               map2 {
+                       cooling-device =
+                               <&fan0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+                       trip = <&cpu_hot>;
+               };
+       };
+};
+
 &emmc_phy {
        status = "okay";
 };
@@ -472,6 +503,13 @@
                };
        };
 
+       fan {
+               motor_pwr: motor-pwr {
+                       rockchip,pins =
+                               <RK_GPIO1 RK_PC2 RK_FUNC_GPIO &pcfg_pull_none>;
+               };
+       };
+
        pmic {
                pmic_int_l: pmic-int-l {
                        rockchip,pins =