Re: mfd regmap irq to handle some cases

[Ashish Jangam <ashish.jangam@kpitcummins.com>]

On Mon, 2012-01-23 at 19:02 +0530, Ashish Jangam wrote:
> 
> > -----Original Message-----
> > From: Mark Brown [mailto:broonie@opensource.wolfsonmicro.com]
> > Sent: Monday, January 23, 2012 5:22 PM
> > To: Ashish Jangam
> > Cc: linux-kernel@vger.kernel.org
> > Subject: Re: mfd regmap irq to handle some cases
> > 
> > On Mon, Jan 23, 2012 at 02:17:03PM +0530, Ashish Jangam wrote:
> > 
> > Please fix your mailer to word wrap within 80 columns.  I've reflowed
> > your text for legibility.
> > 
> > > For a quick fix in regmap irq we may tempt to defer event
> > > clarification after processing of event but there is a problem in this
> > 
> > That's not going to work in general, it means there's a race between
> > handling the interrupt and acknowledging the interrupt which leads to
> > interrupts being dropped if you get a new interrupt before the ack has
> > been written back.
I'm aware of this but added to this there is also another issue specific
to DA9052 that was highlighted.
> > 
> > > approach for some variants of DA9052 and DA9053 when event is cleared
> > > a spurious interrupt gets generated therefore in earlier release of
> > > DA9052/53 MFD module a delay was added. Therefore we need to think on
> > > how to handle such cases in regmap irq.
> > 
> > What are the consequences of the spurious interrupt?
> 
There will processing of false events which is undesirable.