I’m working to attach a GPIO extended board through SPI1 of GPIO in Rock pi 4b, everything is good but there’s SPI data error of verification if the frequency is set to or upper than 2Mhz. Is there any way to fix it?
The system is running on the original Ubuntu image from Rock pi, kernel 4.4.
The dmesg log shows the message below.
[ 3.007011] rockchip-spi ff1d0000.spi: no high_speed pinctrl state
Before this post I do some work on the related issue, it looks like there might be issues if the frequency is higher than 16 or 20Mhz, this is way higher than 2Mhz.