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// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/*
* Device Tree Overlay for the PWM controlled blower fan in connector J3:FAN
* 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$ grep -H . /sys/class/hwmon/hwmon?/name
* /sys/class/hwmon/hwmon0/name:sensor1_thermal
* /sys/class/hwmon/hwmon1/name:sensor2_thermal
* /sys/class/hwmon/hwmon2/name:sensor3_thermal
* /sys/class/hwmon/hwmon3/name:sensor4_thermal
* /sys/class/hwmon/hwmon4/name:pwmfan
* ^ ^^^^^^
*
* # 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/class/hwmon/hwmon4/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/class/hwmon/hwmon4/pwm1
*/
/dts-v1/;
/plugin/;
/*
* Override default PWM fan settings. For a list of available properties,
* see schema Documentation/devicetree/bindings/hwmon/pwm-fan.yaml .
*/
&fan {
/* Available cooling levels */
cooling-levels = <0 50 100 150 200 255>;
/* Four pulses of tacho signal per one revolution */
pulses-per-revolution = <4>;
/* PWM period: 100us ~= 10 kHz */
pwms = <&pwm0 0 100000>;
};
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