Hello !

In my project I need use 2 spi bus : /dev/spidev1.0 and /dev/spi2.0

/dev/spidev1.0 for 3.5inch rpi display

and

/dev/spidev2.0 for 8x8 led matrices, such as  MAX7219-8x32-MCU-Drive-LED

If I am use legacy kernel   (3.4.113-sun7i) both spi buses work well

But if use mainline kernel (4.14.18-sunxi), I can use only 1 spi bus

This is my armbianEnv.txt:

   overlays=spi-spidev spi1 spi2
   param_spidev_spi_bus=1

In this case I can use /dev/spidev1.0

If I set

   param_spidev_spi_bus=2

I can use /dev/spidev2.0

 

How to enable 2 spi buses at the same time ?

 

 

The MAX7219 can easily be driven with bit banging (see my Arduino implementation here: https://github.com/bitbank2/max7219), but you raise a good question. I don't see in the documentation how it would be possible to enable both SPI bus 0 and 1 on AllWinner boards using the device tree overlays text file.

 

@tkaiser Do you know how to specify both buses to be enabled?