52 lines
1.5 KiB
Plaintext
52 lines
1.5 KiB
Plaintext
// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
|
|
/*
|
|
* Device Tree Overlay for the Argon40 HAT blower fan on connector CN7
|
|
* on R-Car V4H ES3.0 Sparrow Hawk board
|
|
*
|
|
* Copyright (C) 2025 Marek Vasut <marek.vasut+renesas@mailbox.org>
|
|
*
|
|
* Example usage:
|
|
*
|
|
* # Localize hwmon sysfs directory that matches the PWM fan,
|
|
* # enable the PWM fan, and configure the fan speed manually.
|
|
* r8a779g3-sparrow-hawk$ ls -1 /sys/devices/platform/pwm-fan-ext/hwmon/hwmon?/pwm?_enable
|
|
* /sys/devices/platform/pwm-fan-ext/hwmon/hwmon0/pwm1_enable
|
|
*
|
|
* # Select mode 2 , enable fan PWM and regulator and keep them enabled.
|
|
* # For details, see Linux Documentation/hwmon/pwm-fan.rst
|
|
* r8a779g3-sparrow-hawk$ echo 2 > /sys/devices/platform/pwm-fan-ext/hwmon/hwmon0/pwm1_enable
|
|
*
|
|
* # Configure PWM fan speed in range 0..255 , 0 is stopped , 255 is full speed .
|
|
* # Fan speed 101 is about 2/5 of the PWM fan speed:
|
|
* r8a779g3-sparrow-hawk$ echo 101 > /sys/devices/platform/pwm-fan-ext/hwmon/hwmon0/pwm1
|
|
*/
|
|
|
|
/dts-v1/;
|
|
/plugin/;
|
|
|
|
&{/} {
|
|
pwm-fan-ext {
|
|
compatible = "pwm-fan";
|
|
#cooling-cells = <2>;
|
|
/* PWM period: 33us ~= 30 kHz */
|
|
pwms = <&pwmhat 0 33334 0>;
|
|
/* Available cooling levels */
|
|
cooling-levels = <0 50 100 150 200 255>;
|
|
fan-shutdown-percent = <100>;
|
|
};
|
|
};
|
|
|
|
/* Page 31 / IO_CN */
|
|
&i2c3 {
|
|
#address-cells = <1>;
|
|
#size-cells = <0>;
|
|
clock-frequency = <400000>;
|
|
status = "okay";
|
|
|
|
pwmhat: pwm@1a {
|
|
compatible = "argon40,fan-hat";
|
|
reg = <0x1a>;
|
|
#pwm-cells = <3>;
|
|
};
|
|
};
|