Re: [PATCH] USB: serial: option: add Fibocom FM350-GL

[Johan Hovold <johan@kernel.org>]

On Thu, Jun 27, 2024 at 10:09:31AM +0200, Bjørn Mork wrote:
> Johan Hovold <johan@kernel.org> writes:
> > On Wed, Jun 26, 2024 at 03:32:23PM +0200, Bjørn Mork wrote:
> >> FM350-GL is 5G Sub-6 WWAN module which uses M.2 form factor interface.
> >> It is based on Mediatek's MTK T700 CPU. The module supports PCIe Gen3
> >> x1 and USB 2.0 and 3.0 interfaces.
> >> 
> >> The manufacturer states that USB is "for debug" but it has been
> >> confirmed to be fully functional, except for modem-control requests on
> >> some of the interfaces.
> >> 
> >> USB device composition is controlled by AT+GTUSBMODE=<mode> command.
> >> Two values are currently supported for the <mode>:
> >> 
> >> 40: RNDIS+AT+AP(GNSS)+META+DEBUG+NPT+ADB
> >> 41: RNDIS+AT+AP(GNSS)+META+DEBUG+NPT+ADB+AP(LOG)+AP(META)(default value)
> >
> > The order here does not seem to match the usb-devices output below (e.g.
> > with ADB as interface 3 and 5, respectively). 
> >
> > Could you just update these two lines so we the interface mapping right?
> 
> Thanks, I didn't notice that.
> 
> This part was copied from the Fibocom AT+GTUSBMODE documentation and
> seems to list supported functions independently of the resulting USB
> interface order.
> 
> I'm afraid I can't verify the actual order since I don't have access to
> this module myself, and there is no way to tell the AT, GNSS, META,
> DEBUG, NPT and LOG functons from eacohother based on USB descriptors.
> 
> The best I can do is dropping these two lines. Is that better?

No, I'll just amend the commit message to clarify that the order is
unspecified. Thanks.

Johan