Re: [PATCH RFC 0/8] USB Type-C alternate mode selection

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

Thu, Dec 11, 2025 at 03:40:24PM +0200, Heikki Krogerus kirjoitti:
> Without going into the code review yet, I'm okay with this in general,
> except with the artificial SID for the USB4. I still don't understand
> why do you guys think we should use that instead of an USB4 specific
> device type?
> 
> I think somebody said earlier that the user space can't see the device
> type of the alt modes? If that's really the case, then I think there
> is some bigger issue here. Are you really sure that if you check the
> device type of an alternate mode for example with udevadm, it does not
> say DEVTYPE=typec_alternate_mode ?
> 
>         % udevadm info -q property --property=DEVTYPE /sys/bus/typec/devices/port0-partner.0
>         DEVTYPE=typec_alternate_mode

Or just use grep :)

        % grep DEVTYPE /sys/bus/typec/devices/port0-partner.0/uevent
        DEVTYPE=typec_alternate_mode

So, if that really does not work, then there is a bug somewhere that
we obviously need to fix.

Please note that the port altmodes are now also part of the bus.

Br,

-- 
heikki