Re: [PATCH v5 6/6] i2c: use an IRQ to report Host Notify events, not alert

From: Wolfram Sang
Date: Tue Nov 22 2016 - 06:49:43 EST


On Mon, Nov 21, 2016 at 11:52:48AM +0100, Benjamin Tissoires wrote:
> Hi Wolfram,
>
> On Nov 07 2016 or thereabouts, Wolfram Sang wrote:
> > On Thu, Oct 13, 2016 at 02:10:40PM +0200, Benjamin Tissoires wrote:
> > > The current SMBus Host Notify implementation relies on .alert() to
> > > relay its notifications. However, the use cases where SMBus Host
> > > Notify is needed currently is to signal data ready on touchpads.
> > >
> > > This is closer to an IRQ than a custom API through .alert().
> > > Given that the 2 touchpad manufacturers (Synaptics and Elan) that
> > > use SMBus Host Notify don't put any data in the SMBus payload, the
> > > concept actually matches one to one.
> >
> > I see the advantages. The only question I have: What if we encounter
> > devices in the future which do put data in the payload? Can this
> > mechanism be extended to handle that?
>
> I guess I haven't convinced you with my answer. Is there anything I can
> do to get this series in v4.10 or do you prefer waiting for v4.11?

I consider this v4.10 material. I was thinking a little about how to not
lose data with consecutive interrupts but then -EBUSY came along.
Nonetheless, it looks to me like the proper path to follow...

Thanks,

Wolfram

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