[PATCH dev-5.2 0/2] i2c: aspeed: Add H/W timeout support

[Andrew Jeffery]

On Thu, 5 Sep 2019, at 09:10, Jae Hyun Yoo wrote:
> Hi Andrew,
> 
> On 9/4/2019 4:12 PM, Andrew Jeffery wrote:
> > On Thu, 5 Sep 2019, at 08:31, Jae Hyun Yoo wrote:
> >> Hi Joel,
> >>
> >> On 9/4/2019 3:54 PM, Joel Stanley wrote:
> >>> Hi Jae,
> >>>
> >>> On Wed, 4 Sep 2019 at 20:08, Jae Hyun Yoo <jae.hyun.yoo at linux.intel.com> wrote:
> >>>>
> >>>> In case of multi-master environment, if a peer master incorrectly handles
> >>>> a bus in the middle of a transaction, I2C hardware hangs in slave state
> >>>> and it can't escape from the slave state, so this commit adds slave
> >>>> inactive timeout support to recover the bus in the case.
> >>>>
> >>>> By applying this change, SDA data-low and SCL clock-low timeout feature
> >>>> also could be enabled which was disabled previously.
> >>>
> >>> Please consider sending your RFC patches to the upstream list. You
> >>> have a big backlog of patches now.
> >>
> >> Thanks for the reminding. I can't send the RFC patches yet because QEMU
> >> H/W model isn't ready yet. I'm still waiting for the fix from Cedric.
> > 
> > QEMU shouldn't be preventing you from sending patches upstream, rather
> > it prevents us from enabling the buffer mode support in the OpenBMC
> > kernel tree. You should be sending all patches upstream as early as possible.
> 
> I met a QEMU issue when I was upstreaming a patch set last year:
> https://lists.ozlabs.org/pipermail/linux-aspeed/2018-September/000750.html
> 
> If OpenBMC community accepts the QEMU issue, I can submit the RFC
> patches to upstream. Will submit the patch set soon to linux tree.

Ah, didn't realise it was Guenter that ran into it. We have some changes[1] in
Cedric's aspeed-4.2 qemu tree - do you mind testing it out? If those patches
resolve the issue Maybe we could point Guenter at that tree, though really we
should get the fixes upstream so this isn't an issue.

[1] https://github.com/legoater/qemu/compare/59dda66ab756e52e6a9c1ef89660d30b3769f63c...aspeed-4.2

Cheers,

Andrew