Re: usb: dwc2: regression on MyBook Live Duo / Canyonlands since 4.3.0-rc4

From: Arnd Bergmann
Date: Thu May 12 2016 - 07:56:06 EST


On Thursday 12 May 2016 11:58:18 Christian Lamparter wrote:
> > > > Detecting the endianess of the
> > > > device is probably the best future-proof solution, but it's also
> > > > considerably more work to do in the driver, and comes with a
> > > > tiny runtime overhead.
> > >
> > > The runtime overhead is probably non-measurable compared with the cost
> > > of the actual MMIOs.
> >
> > Right. The code size increase is probably measurable (but still small),
> > the runtime overhead is not.
>
> Ok, so no rebuts or complains have been posted.
>
> I've tested the patch you made in: https://lkml.org/lkml/2016/5/9/354
> and it works:
>
> Tested-by: Christian Lamparter <chunkeey@xxxxxxxxxxxxxx>
>
> So, how do we go from here? There is are two small issues with the
> original patch (#ifdef DWC2_LOG_WRITES got converted to lower case:
> #ifdef dwc2_log_writes) and I guess a proper subject would be nice.
>
> Arnd, can you please respin and post it (cc'd stable as well)?
> So this is can be picked up? Or what's your plan?

(I just realized my reply was stuck in my outbox, so the patch
went out first)

If I recall correctly, the rough consensus was to go with your longer
patch in the future (fixed up for the comments that BenH and
I sent), and I'd suggest basing it on top of a fixed version of
my patch.

Felipe just had another idea, to change the endianess of the dwc2
block by setting a registers (if that exists). That would indeed
be preferable, then we can just revert the broken change that
went into 4.4 and backport that fix instead.

Arnd