IMX6ULL ADC OUTPUT VALUES INCORRECT

sheik — Thu, 22 Oct 2020 14:13:28 GMT

We have been using iMX6uLL processors with Linux kernel version 4.1.15 on our custom board. It has been working fine and we have been getting accurate voltage output values when we probe "/sys/bus/iio/devices/iio:device0/in_voltage5_raw".

We are currently switching to Linux kernel 4.14.98 on the same hardware. However, when we probe the value on "/sys/bus/iio/devices/iio:device0/in_voltage5_raw" we are receiving values that are different from the expected output voltage values.

Please let me know if there are any changes/patches to be applied on the driver source code (vf610_adc.c) to calibrate the ADC output values to the expected output voltage values.

Re: IMX6ULL ADC OUTPUT VALUES INCORRECT

igorpadykov — Fri, 23 Oct 2020 00:59:27 GMT

Hi sheik

what bsp used in the case, as not all " Linux kernel 4.14.98" support i.MX6ULL, please try

Linux 4.14.98_2.0.0_ga from NXP official source.codeaurora.org/external/imx/linux-imx repository

https://source.codeaurora.org/external/imx/linux-imx/tree/drivers?h=imx_4.14.98_2.0.0_ga

with uboot ver.v2018.03:

https://source.codeaurora.org/external/imx/uboot-imx/tree/?h=imx_v2018.03_4.14.98_2.0.0_ga

One can test it on i.MX6ULL EVK with Demo Image:

i.MX 6UltraLite, i.MX 6ULL, i.MX 6ULZ, i.MX 7Dual Boards

Best regards
igor

i.MX ProcessorsのトピックIMX6ULL ADC OUTPUT VALUES INCORRECT

IMX6ULL ADC OUTPUT VALUES INCORRECT

Re: IMX6ULL ADC OUTPUT VALUES INCORRECT