I filed a bug report here: github.com/raspberrypi/linux/issues/3779

Hopefully we get some feedback on it.

I learned a new command (sudo lsusb) from your bug report, so I thought I would try it out. Before that I did a sudo apt update && sudo apt upgrade. I subsequently found that all my USB devices were listed both by lsusb and sudo lsusb. Has kernel 5.4 perhaps been fixed? My SSD installation seems to be working including the KStars 3.5.0 beta.

Looks like I have a similar problem...
Recently, I added a ZWO EAF focuser to my setup.
Tried it first with AZ-GTi, ASI294 and ASI120 on RPI 4 B (4Gb). Stellarmate 1.5.2.
All worked very well for several sessions.
Switched to Stellarmate 1.5.3 with the same hardware. Again, all worked very well for several sessions.
Today, I put my rig on a HEQ5 and boom... no ASI120, no EAF (they are connected to ASI294's hub).
After some troubleshooting I found a workaround.
(All my USB devices are connected to a USB3 powered hub).

-- if I disconnect HEQ5 EQDir USB cable from the hub and start the system up - everything comes up OK (except for the mount of course)
-- then I just connect EQDir cable and power on the HEQ5 and it comes up too

Strange thing is that it is not enough to power off the mount - the cable has to be disconnected from the hub.

Oh well... The workaround works.
Maybe it's a power-draw issue as someone suggested - tomorrow I'll try a separate power supply for RPI.
Currently I power everything with a single 12V/5A brick.

Thanks!

I can confirm that ANY FTDI cable causes this problem. As soon as all the FTDI cables are removed, the system is back to normal operation with all USB devices accessible. I reported this on the bug report for the Kernel. It's not limited to EQDir, but any FTDI chip would cause the same issue.

My optimism has been disappointed - my one device with a FTDI chip (the Pegasus Astro PPB) doesn’t seem to work with Ekos anymore. The command lsusb does list the device but Ekos struggles with and ultimately fails to connect.

And that's what I said above. If you guys can contribute to the Github issue that would be great as well. The more data they have the better. I tried downgrading to Kernel 5.4.35 but still have the same issue with FTDI chipsets making USB on external hub unusable.

but it did work with my AZ-GTi mount which used an FTDI EQDir cable.
However, once I switched to HEQ5 which also used an FTDI EQDir cable (different brand/make) things went bad.

This cable works with no issues (for me): www.amazon.com/gp/product/B014GZTCC6
How do i report to developers?

I have started to review linux kernel tree for usb serial - see: github.com/torvalds/linux/tree/master/drivers/usb/serial
As for now I cannot find a commit that introduces access rights issue on usb bus. Maybe you can find it.

That was one of the first things I tried. I tried to replicate the issue on my Linux laptop with the same kernel versions. But I could not replicate it on my laptop. I wanted to be able to do a "git bisect" to find the offending commit. But I suspect the problem is in the Raspberry Pi specific changes, and probably not in vanilla Linux.

What you're saying is the problem does not occur on x86/x64 architecture, right? I would be surprised if there is any difference between vanilla and raspberry kernel for drivers/usb/serial branch. Could you do diff between the two?

Yes, x64. Debian with prebuilt kernels, as well as custom built kernels, trying to get the exact same kernel version as what's used on the Pi.

When I was going through this exercise, I compared the ftdi_sio.c driver file, and noticed no difference of importance. There are differences, because it seems the Raspberry Pi kernel might be cherry picking changes from newer kernels. Not sure though.

Hi All,

I have just run into this problem. Camera tabs come up in indi but will not connect. I usually do a nightly build update every few days so this was all working last weekend. I am running an Odroid XU4 (running Ubuntu Mate 18.04) with a powered USB3 hub (motor focus and dew heater electronics all in one box so do not have access to the odroid based USB ports only the hub. I am able to connect to the cameras using PhD2 and loop images from both cameras so this would suggest that the problem is with EKOS/indi.
I tried to roll back to the last stable version and encountered some errors and appear to be stuck on 3.5 beta, although I will keep trying but thought that I would post in case there is a quick fix
Are there any work arounds currently for non Rpi single board computers?

Cheers,

Mike