How to configure dtb and overlays on bananapi m1+ to get /dev/spidev0.0 and /dev/spidev0.1 at the same time

[jimw]

I've tried many permutations of overlays and user-overlays and I can get /dev/spidev0.0 or /dev/spidev0.1 to be present, but I can't seem to get both simultaneously.  I need both to migrate a project from an older Fedora distribution relying on modprobe to the latest version of Armbian.  Any suggestions will be greatly appreciated!

 

I started with very recent Armbian 23.02 Bullseye XFCE downloaded from arbian.com/banana-pi-plus ..

 

Armbian_23.02.2_Bananapi_bullseye_current_5.15.93_xfce_desktop.img

 

and I added the following to the /boot/armbianEnv.txt file, as described in the Armbian page associated with the BananaPi M1+ ..

  

fdtfile=sun7i-a20-bananapi-m1-plus.dtb

 

I also added these overlays at the same file ..

 

overlay=spi-spidev spi-add-cs1

param_spidev_spi_bus=0

 

After reboot, I see one /dev/spidev device:

 

 # ls /dev/sp*

 /dev/spidev0.0

 

If instead, I also add ..

 

param_spidev_spi_cs=1

 

Then after reboot, I see a device for the other chip select, only ..

 

# ls /dev/sp*

 /dev/spidev0.1

 

but I can't find a means to have access to both simultaneously. 

 

As an aside, I also tried the following;  Through some searching in the forum, I found a link to a promising overlay ..

 

armbian / sunxi-DT-overlays / examples / spi-double-spidev-cs.dts

 

Contents shown below ..

 

I downloaded this and compiled it using ..

 

dtc -@ -I dts -O dtb -o /boot/overlay-user/spi-double-spidev-cs.dtbo spi-double-spidev-cs.dts

 

Then, since the thread said, "You will still need to use spidev-add-cs1 overlay but remove spi-spidev one because the custom one will be used instead of it,"  I used the following in the /boot/armbianEnv.txt file ..

 

overlays=spi-add-cs1

user_overlays=spi-double-spidev-cs

 

I confirmed the user overlay did load ..

 

 

But this produced neither /dev/spidev0.0 or /dev/spidev0.1.

 

Any ideas?  I'd rather not have to compile the kernel since I'd have to outfit a whole new development environment for that, so I'm hoping this can be done with dts or dtbo files.  Any tips or hints on which direction I should go next will be GREATLY appreciated. Thank you.

 

 

[Ryzer]

Hi There,

 

Those overlays are a bit old but should hopefully work with one minor change. Try replacing the compatible field with compatible = "armbian,spi-dev" and see if this works. From what I understand there was a change to the kernel since version 5.15 which removed the old spidev driver.

 

Best of luck 

 

Ryzer