USB serial ports by serial number

[Hans Petter Selasky]

On 2019-10-08 16:20, Ed Maste wrote:
> On Thu, 3 Oct 2019 at 02:43, Oleksandr Rybalko <ray at ddteam.net> wrote:
>>
>> Hi,
>>
>> Looks like you are lucky guy :)
>> Most of USB-serial devices have "very stable" serial number :)
>> more than 50% have S/N "0123456789".
> 
> cp210x USB-serial devices are ubiquitous and cheap and it's easy to
> set the serial number.
> 
> I have a trivial port of the 'cp210x-cfg' tool at
> https://github.com/emaste/cp210x-cfg.

Hi,

How about the following:

We can add a TUNEABLE search to every USB device attach, which if set, 
will serve as the base unit number for that device.

Then you could simply add to /boot/loader.conf :

hint.usb.0.1.1.1.0.unit=128
hint.usb.0.1.1.2.0.unit=129

These numbers can be printed by usbconfig for example, based on:

1) Host controller number [0..xxx]
2) Array of USB port numberr [1.255]
3) Interface index number [0..xxx]

To help setting up the system.

--HPS