Hi Jaye,
On Thursday, 7 November 2024 22:56:52 GMT MJ Inabnit wrote:
> I am going to retire an old thinkpad with a real serial port. Found
> some good how-to about writing a udev rule to id and make new device for
> usb to serial adapters. One rule works great for my TS-590sg, but my
> second adapter (which has two serial ports) rule isn't working.
>
We have been doing similar in my online club - sadly it's 2 TNCs with onboard
USB/Serial devices not 2 ports on one adaptor. I do have one of those *and* a
radio that enumerates as 2 serial ports attached just now, so that'll maybe
help to point you in the right direction!
> Is there anyone here able to assist. If not, perhaps someone can point
> out where I might get some assistance? Googled for weeks and not
> finding the key to my rule.
We've been using serial numbers to modify the symlink so the ports have their
service name on them, see the first part of the linux notes:
https://wiki.oarc.uk/packet:ninotnc?s[]=udev#misc_linux_notes
How is the device enumerating currently - I assume it's connecting and
presenting new ports in `/dev` ?
What about somewhere like `/dev/serial/by-id`?
If I look in my raspi's /dev/serial/by-id, I see what is in the attached text
file.
Reading `udevadm info -a /dev/ttyUSB0` and `udevadm info -a /dev/tty/USB1` has
pointed me to ATTRS{bInterfaceNumber}=="00" - I wonder if there is a way to
combine that, the serial number of the adaptor ATTRS{serial} to create
different devices.
There was also a hint of this approach here, where the two serial ports showed
different serial numbers and that was used to give then pretty names:
https://wiki.oarc.uk/persistent_sound_interface?
s[]=udev#transceiver_device_names
Hopefully that's enough of a starter for you to break the deadlock! If not,
feel free to reach out again.
Cheers,
--
Hibby <hibby@debian.org>
Debian Developer
Packet Radioist
MM0RFNhibby@rpi4-20240904:~$ ls -al /dev/serial/by-id/ total 0 drwxr-xr-x 2 root root 100 Sep 14 23:00 . drwxr-xr-x 4 root root 80 Aug 25 17:35 .. lrwxrwxrwx 1 root root 13 Sep 14 23:00 usb-Microchip_Technology_Inc._MCP2221_USB-I2C_UART_Combo-if00 -> ../../ttyACM1 lrwxrwxrwx 1 root root 13 Sep 14 23:00 usb-Silicon_Labs_CP2105_Dual_USB_to_UART_Bridge_Controller_00BC83E4-if00-port0 -> ../../ttyUSB0 lrwxrwxrwx 1 root root 13 Sep 14 23:00 usb-Silicon_Labs_CP2105_Dual_USB_to_UART_Bridge_Controller_00BC83E4-if01-port0 -> ../../ttyUSB1
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