How to enable spidev interface on SoC Allwinner?

I intend to add support for displays with the spi interface to my OLEDproc add-on.

I've spent many hours on failed attempts, and now I really don't know what to do next.

I work with Orange Pi 3 (H6) and Orange Pi PC (H3) boards. Unfortunately, I was not successful with any of them. No /dev/spidevX.X interface appears (I use the ls /dev/sp* command to check).

At first I tried it with Armbian and I was successful there. I then copied the overlay files (which it worked with in Armbian) to LibreELEC,

but in LibreELEC these files do not work. There is probably something else here, but I can't find it. Can you help me please ?

Note:

1. I'm working on version 10.0.2

2. In Armbian I used these overlay files: overlays.zip

Thank you very much for your answer. I hope we are going in the right direction, but unfortunately, I still don't have a /dev/spidevX.X device.

I fixed the overlay - see the attachment, but the result is none. I tried to use the same file in Armbian and it works there.

Can you please think about what else needs to be done?

Note:

As a first attempt, I used the string "ge, achc", but it didn't work in Armbian either. I immediately found out why. I have in Armbian 5.15.43 Linux version and there are compatible strings a little different - "ge, achc" is not there. So I used "dh, dhcom-board" and it is in both version 5.10.76 (my LibreELEC) and version 5.15.43.

Then it started working in Armbian, but not in LibreELEC.

Edit:

I noticed that Linux 5.10.X lacks (as opposed to Linux 5.15.43) the following structure:

static const struct spi_device_id spidev_spi_ids[] = {
{ .name = "dh2228fv" },
{ .name = "ltc2488" },
{ .name = "sx1301" },
{ .name = "bk4" },
{ .name = "dhcom-board" },
{ .name = "m53cpld" },
{ .name = "spi-petra" },
{ .name = "spi-authenta" },
{},
};

Could it be the problem?

sun8i-h3-spi-spidev0.dts.zip

Quote from jernej

Not sure what problem you see with compatibles - all 5.10 versions I checked have same compatible array.

I did not say the opposite. I probably wrote it somehow confused, I'm sorry.

So once again. I used the string "ge, achc" as the first attempt and it didn't work (in LibreELEC). I wanted to verify that it works at least in Armbian. But it didn't work. That's why I looked at what Linux is in Armbian. There is 5.15.43. So I looked in the appropriate spidev.c file and there I found that the compatible array does not contain the string "ge, achc". So I used the string "dh, dhcom-board", which is found in both versions. Then I tried it in both Armbian and LibreELEC. It worked in Armbian, it didn't work in LibreELEC.

Quote from jernej

I just noticed that CONFIG_SPI_SPIDEV is not even enabled for 32-bit AW SoCs, but it is for 64-bit. So it should work on H6, but not on H3.

How do I understand that? This means that for H3 there is no chance for it to work in LibreELEC (in Armbian it works!).

I'll try to see if it really works at least on H6.

Above all - thank you for your patience with me.

In the meantime, I tried a modified overlay (with the string "dh, dhcom-board") on H6. But unfortunately, without success. So CONFIG_SPI_SPIDEV is probably not the only problem.

Note:

1) If I do image bulding myself, can I create an image (where CONFIG_SPI_SPIDEV will be allowed) for H3 as well?

2) In the future - is it possible to enable CONFIG_SPI_SPIDEV for H3 in the official version? It's a pretty common thing to connect a display to Kodi, so why can't it be with a spi interface?

Not everyone will be able to build a WiFi version.

1. mount -o remount, rw / flash

2. I copy the file sun50i-h6-spi-spidev1.dtbo to the directory /flash/overlays

3. I edit the file /flash/extlinux/extlinux.conf and in the line FDTOVERLAYS I add the parameter /overlays/sun50i-h6-spi-spidev1.dtbo

4. mount -o remount, ro / flash

5. reboot

Note:

My extlinux.conf file looks like this:

LABEL LibreELEC
LINUX / KERNEL
FDT /sun50i-h6-orangepi-3.dtb
FDTOVERLAYS /overlays/sun50i-h6-i2c0.dtbo /overlays/sun50i-h6-spi-spidev1.dtbo
APPEND boot = UUID = 0908-1419 disk = UUID = 8cd4f88f-17df-48ce-bec6-cca1eb844534 quiet console = ttyS0,115200 console = tty1

sun50i-h6-spi-spidev1.dtbo.zip

Quote from jernej

I suppose i2c0 overlay works correctly?

Yes, it works properly. I have a normally connected LCD display so, but it's disconnected now. Well, we'll see how it works on H3 after build or tomorrow with LE11. It's easier for me to work on H3 at the moment, I have a purely development version with a well-available gpio connector.

I report partial success!

Today's nightly LE11 Orange Pi PC is already working - /dev/spidev0.0 has appeared.

But on SoC H6 I'm still without spidev. I also tried a fresh installation of LE11 on a clean SD card, but nothing. I even tried it on two boards (Pi 3 and Pi LIte 2), but in vain.

I also wanted to try my own build LE 10 on the OPi PC, but it won't start at all - see the picture. Until recently, however, I did the building without any problems - I have no idea what is wrong (whether the problem is on my side).

Quote from jernej

Do you have serial adapter?

Yes, I had a serial console connected during boot and it looked like the overlay files were loaded without any problems.

I'll make more attempts tomorrow.

Thank you for your help !

I have other findings:

1. I installed nightly OPi-PC-LE10. Result: no spidev

2. I decompiled the FDT files (they are attached). It looks like it should work, but it doesn't work.

3. Due to the behavior on OPi-PC (works with nightly LE11, but not with nightly LE10), I also tried a clean installation of nightly LE11 on OPi-3. Result: no spidev

What are we going to do next?

OPI-FDT-ALL.zip

Quote from jernej

I have no idea why it doesn't work on LE10 H3 image. Can you confirm that you actually get other issues like those described before?

I'm sorry, but I don't understand what you mean. To be sure, however, I performed a new clean installation of the latest LE10 nightly and reapplied the overlay. Without success.

I'm happy to report another partial success:

With the latest nightly LE11, /dev/spidev1.0 already exists on OPi3 (H6)!

Conversely, even with the latest nightly LE10, there is no /dev/spidevX.X (neither H3 nor H6).

It occurred to me that it might help to find the cause when you see the result of the find /sys/ -name '*spi*' command.

So I did it for all four cases. The result is in the attachment.

However - it is no longer absolutely necessary to solve it for LE10. I can continue to develop the OLEDproc add-on on LE11. But of course it would be better if it worked for LE10 as well.

find-sys-name-spi.zip