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orangepi-xunlong
GitHub Repository: orangepi-xunlong/orangepi-build
 Path: blob/next/external/packages/blobs/rockchip/pwm-fan.sh
18120 views
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#!/bin/bash

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if [ ! -d /sys/class/pwm/pwmchip0 ]; then

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    echo "this model does not support pwm."

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    exit 1

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fi

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if [ ! -d /sys/class/pwm/pwmchip0/pwm0 ]; then

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    echo -n 0 > /sys/class/pwm/pwmchip0/export

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fi

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sleep 1

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while [ ! -d /sys/class/pwm/pwmchip0/pwm0 ];

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do

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    sleep 1

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done

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ISENABLE=`cat /sys/class/pwm/pwmchip0/pwm0/enable`

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if [ $ISENABLE -eq 1 ]; then

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    echo -n 0 > /sys/class/pwm/pwmchip0/pwm0/enable

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fi

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echo -n 1000000 > /sys/class/pwm/pwmchip0/pwm0/period

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echo -n 1 > /sys/class/pwm/pwmchip0/pwm0/enable

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# max speed run 5s

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echo -n 500000 > /sys/class/pwm/pwmchip0/pwm0/duty_cycle

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sleep 5

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echo -n 500000 > /sys/class/pwm/pwmchip0/pwm0/duty_cycle

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# declare -a CpuTemps=(55000 43000 38000 32000)

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# declare -a PwmDutyCycles=(1000 20000 30000 45000)

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declare -a CpuTemps=(75000 63000 58000 52000)

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declare -a PwmDutyCycles=(500000 650000 800000 950000)

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declare -a Percents=(100 75 50 25)

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DefaultDuty=999990

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DefaultPercents=0

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while true

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do

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	temp=$(cat /sys/class/thermal/thermal_zone0/temp)

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	INDEX=0

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	FOUNDTEMP=0

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	DUTY=$DefaultDuty

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	PERCENT=$DefaultPercents

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	for i in 0 1 2 3; do

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		if [ $temp -gt ${CpuTemps[$i]} ]; then

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			INDEX=$i

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			FOUNDTEMP=1

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			break

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		fi

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	done

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	if [ ${FOUNDTEMP} == 1 ]; then

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		DUTY=${PwmDutyCycles[$i]}

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		PERCENT=${Percents[$i]}

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	fi

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	echo -n $DUTY > /sys/class/pwm/pwmchip0/pwm0/duty_cycle;

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        # echo "temp: $temp, duty: $DUTY, ${PERCENT}%"

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        # cat /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_cur_freq

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	sleep 2s;

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done

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