USB-C smartphone does not detect correctly as UMS

[Tomasz CEDRO]

Hello world,

I have problems detecting a smartphone over USB-C - at first it only
changes over the USB, then I switch it to be a USB Mass Storage, but I
see no disk.. the same with different modes (i.e. Media Transfer,
Picture Transfer, etc)..

DMESG shows only device connected and disconnected in a loop..

What is the problem here? VID/PID is unknown to the system or it does
not present itself correctly as known USB endpoint?

Any hints appreciated :-)

Best regards,
Tomek

-- 
CeDeROM, SQ7MHZ, http://www.tomek.cedro.info