WhyCan Forum(哇酷开发者社区)

root@TinaLinux:/sys/devices/platform/soc@3000000/2000c00.pwm/pwm/pwmchip0# ls
device                power                 unexport
export                subsystem             waiting_for_supplier
npwm                  uevent
root@TinaLinux:/sys/devices/platform/soc@3000000/2000c00.pwm/pwm/pwmchip0# echo
3 > export
root@TinaLinux:/sys/devices/platform/soc@3000000/2000c00.pwm/pwm/pwmchip0# cd pw
root@TinaLinux:/sys/devices/platform/soc@3000000/2000c00.pwm/pwm/pwmchip0/pwm3# echo 1 > enable
[  296.587997] sunxi_pwm_enable_dual: can't parse pwm device
sh: write error: No such device

如上所示，使能PWM时，提示 sunxi_pwm_enable_dual: can't parse pwm device
sh: write error: No such device
请问这个是啥原因，设备树和内核都按照文档修改了