We’re trying to get SPI working with Linaro Linux on a Dragonboard 410c and/or an Geniatech DB4 (https://www.geniatech.com/product/developer-board-4/). After some hardware issues, which we figured out, we’re now running into somewhat more difficult issues.
Installed SpiDev on a clean image of Linaro. We create some code (as well in C as in NodeJS) which sends some bytes over SPI. With an oscilloscope we see the bytes literally come by, so that part seems fine.
The chip select seems to stay high and doesn’t get low when bytes arrive. Also speed settings don’t seem to ge applied. It’s almost like there is a secondary process that overwrites these kinds of settings (spi_cup?). As said the port itself seems fine we see the the bytes being sent over it.
Tried on the Dragonboard 410c and the Geniatech DB4 with the same result, so it doesn’t seem a hardware problem?
Any ideas? More than happy to provide more details if required!
Thank you for your time!