[v4,2/2] usb/gadget: Add driver for Aspeed SoC virtual hub

[Felipe Balbi <balbi@kernel.org>]

Hi,

Benjamin Herrenschmidt <benh@kernel.crashing.org> writes:
> On Thu, 2018-03-15 at 08:03 +1100, Benjamin Herrenschmidt wrote:
>> > > Do you have more comments for the rest of the driver or that's it ?
>> > 
>> > so far, that's it.
>> 
>> Ok. I'll re-send.
>
> So I'll resend in a minute, doing a few more tests, however, I've
> noticed something which I wont' have time to track down til at
> best next week, I wonder if it's normal/expected.
>
> If I just create a mass storage function set to be "removable" and
> "cdrom" with no file attached,  and enable it, I get an endless stream
> of resets. It looks like the host constantly does USB resets.
>
> I suspect the host is sending SCSI commands that fail and resets
> as a result, but that's spamming both logs and is rather ... sub
> optimal.
>
> Do we know what's going on ? Is this just TEST_UNIT_READY or some other
> media check ? Or are we missing some commands we should actually
> implement in the mass storage gadget ?

enable debugging for mass storage, there's a lot of intersting
information there.