4.10-rc3 rpi issues

[Stefan Wahren]

Hi Gerd,

Am 16.01.2017 um 11:53 schrieb Gerd Hoffmann:
>   Hi,
>>> And, yes, 4.9 dwc2 has no problems handling all three devices.
>> Could you please bisect this issue?
> Hmm, that appears to be quite a challenge.  Behavior isn't very
> consistent ...
>
>  * On 4.9.x wifi works every time.
>  * On 4.10-rc3 wifi fails every time, silently (i.e. no errors
>    in the logs).
>
> While trying to bisect things I've seen (additionally to the two above):
>
>  * failure to load the firmware.
>  * wlan0 trying to connect to ap, but timing out.
>
> Sometimes even the very same kernel showed different behavior when
> booted multiple times.
>
> USB not working reliable can certainly explain all the different error
> cases above, so I decided to rate a kernel as "good" if it worked fine
> three boots in a row and "bad" otherwise, no matter how it failed.  That
> landed at commit 288660b88deee3c625f1c17d16bdd690bffe35c7.  Some virtio
> patch.  Looks bogus.  Nevertheless tried v4.10-rc3 with that one
> reverted.  wifi still broken, as expected.  Hmm.

maybe we should try a different strategy:

* checkout tag 4.10-rc4
* revert all dwc2 commits until ffc4b4067e1bb639834a716b4148efce736b2ba6 ("
usb: dwc2: cleanup with list_first_entry_or_null()")

So we are able to see if it's dwc2 related or not.

Btw wifi isn't a fast test scenario, is the keyboard issue reliable?