On the rpi machines specifying a cs_pin causes confusion. Use cs_pin: rpi:None, as the Linux kernel spi device driver will automatically drive the CS pin associated with the given SPI device.
Also, I’ve found that if you did use a config that tried to manually alter the GPIO pin, it can put the machine in a confusing state. Remove any references to GPIO18 from the config and then perform a full hardware reboot of the rpi.
Finally, I’ve not tested using SPI1 on the rpi, so I can’t say if it will work or not.
-Kevin