[PATCH 1/2] kernel: usb: Autoprobe g_serial

[Linus Walleij]

On Sun, Nov 19, 2023 at 2:27 PM Chuanhong Guo <gch981213 at gmail.com> wrote:
> On Sun, Nov 12, 2023 at 6:04 AM Linus Walleij <linus.walleij at linaro.org> wrote:
> >
> > For devices using USB gadget serial we need to probe the modules
> > usb_f_acm and g_serial in order, then the available UDC (USB device
> > controller) interface will be hooked up to a serial port as
> > /dev/ttyGS0. (On the host side this appears as /dev/ttyACM0
> > when plugging in the USB cable.)
> >
> > I don't quite understand why this wasn't done before for the
> > module explicitly called kmod-usb-serial.
>
> The g_*.ko gadget modules conflict with each other. I think
> it isn't loaded by default to prevent that when users decided
> to install multiple of them.
>
> I made an init script to setup USB gadget using the "modern"
> configfs approach:
> https://github.com/openwrt/openwrt/pull/14005
> Maybe you can make use of this one instead? :)

This is a step in the right direction as it moves toward using configfs
as is custom these days, approved.

I think I would need an example of how to utilize this for the serial
gadget though...

Yours,
Linus Walleij