Re: /dev/ttyUSB0 file disappears on Ubuntu 22.04

[Greg KH <greg@kroah.com>]

On Wed, Jun 01, 2022 at 07:37:45PM +0300, TonicLab.ru wrote:
> Hi all,
> 
> This problem appeared on a freshly installed Ubuntu 22.04 desktop. Not sure
> I need to post this here.
> 
> When I'm attaching a ftdi device into usb everything looks great but there's
> no /dev/ttyUSB0 file. Seems it created and then disappeared. I tried to
> remove brltty package (as some recommends on the net) but it didn't help.
> The same ftdi device works on older Ubuntu version w/o any problems.
> 
> I'm having this in syslog:
> Jun  1 16:58:09 qgs-comp kernel: [  538.642086] usb 2-1.5: new full-speed
> USB device number 5 using ehci-pci
> Jun  1 16:58:10 qgs-comp kernel: [  538.756437] usb 2-1.5: New USB device
> found, idVendor=0403, idProduct=6001, bcdDevice= 6.00
> Jun  1 16:58:10 qgs-comp kernel: [  538.756445] usb 2-1.5: New USB device
> strings: Mfr=1, Product=2, SerialNumber=3
> Jun  1 16:58:10 qgs-comp kernel: [  538.756448] usb 2-1.5: Product: USB
> Serial
> Jun  1 16:58:10 qgs-comp kernel: [  538.756450] usb 2-1.5: Manufacturer:
> FTDI
> Jun  1 16:58:10 qgs-comp kernel: [  538.756452] usb 2-1.5: SerialNumber:
> FT0KKBIF
> Jun  1 16:58:10 qgs-comp kernel: [  538.759677] ftdi_sio 2-1.5:1.0: FTDI USB
> Serial Device converter detected
> Jun  1 16:58:10 qgs-comp kernel: [  538.759713] usb 2-1.5: Detected FT232RL
> Jun  1 16:58:10 qgs-comp kernel: [  538.760546] usb 2-1.5: FTDI USB Serial
> Device converter now attached to ttyUSB0

It was created here.

> Jun  1 16:58:01 qgs-comp colord-sane: message repeated 2 times: [
> io/hpmud/musb.c 2101: Invalid usb_open: Permission denied]
> Jun  1 16:58:10 qgs-comp mtp-probe: checking bus 2, device 5:
> "/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5"
> Jun  1 16:58:10 qgs-comp mtp-probe: bus: 2, device: 5 was not an MTP device
> Jun  1 16:58:10 qgs-comp systemd-udevd[5394]: 2-1.5: Failed to create/update
> device symlink '/dev/ttyUSB0', ignoring: File exists

See it's still there.

> Jun  1 16:58:10 qgs-comp snapd[942]: hotplug.go:199: hotplug device add
> event ignored, enable experimental.hotplug
> Jun  1 16:58:10 qgs-comp mtp-probe: checking bus 2, device 5:
> "/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5"
> Jun  1 16:58:10 qgs-comp mtp-probe: bus: 2, device: 5 was not an MTP device
> Jun  1 16:58:10 qgs-comp colord-sane: io/hpmud/musb.c 2101: Invalid
> usb_open: Permission denied

I do not see it going away.

Are you sure it is gone?  Any further log messages?

thanks,

greg k-h