MP135 尝试使用 ADC Buffer Enable报错，求助！！

chiefbazon

尝试使用MP135的ADC DMA Buffer功能时，显示sh: write error: Invalid argument。
指令执行如下：
[root@ATK-DLMP135 /sys/devices/platform/soc/48003000.adc/48003000.adc:adc@0/iio:device1/scan_elements]#echo 1000 > "/sys/bus/iio/devices/iio:device1/scan_elements/length"
[root@ATK-DLMP135 /sys/devices/platform/soc/48003000.adc/48003000.adc:adc@0/iio:device1/scan_elements]#echo 1 > "/sys/bus/iio/devices/iio:device1/scan_elements/in_voltage0_en"
[root@ATK-DLMP135 /sys/devices/platform/soc/48003000.adc/48003000.adc:adc@0/iio:device1/scan_elements]# grep "" *
in_voltage0_en:1
in_voltage0_index:0
in_voltage0_type:le:u12/16>>0
[root@ATK-DLMP135 /sys/devices/platform/soc/48003000.adc/48003000.adc:adc@0/iio:device1/scan_elements]#echo 1 > "/sys/bus/iio/devices/iio:device1/buffer/enable"
sh: write error: Invalid argument

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