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.
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