RE: [PATCH v2 1/4] MFD: Palmas: Check if interrupts property existsand then only request irq

[J, KEERTHY]

Hi Stephen,

> -----Original Message-----
> From: Stephen Warren [mailto:swarren@xxxxxxxxxxxxx]
> Sent: Wednesday, June 19, 2013 12:42 AM
> To: J, KEERTHY
> Cc: linux-omap@xxxxxxxxxxxxxxx; broonie@xxxxxxxxxx;
> ldewangan@xxxxxxxxxx; sameo@xxxxxxxxxxxxxxx; grant.likely@xxxxxxxxxxxx;
> swarren@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-
> doc@xxxxxxxxxxxxxxx; gg@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v2 1/4] MFD: Palmas: Check if interrupts property
> exists and then only request irq
> 
> On 06/18/2013 11:33 AM, J, KEERTHY wrote:
> > Stephen Warren wrote at Tuesday, June 18, 2013 10:53 PM:
> ...>> No, you should just check the IRQ number.
> >
> > Hmmm...so something like (!i2c->irq)
> 
> Yes.

Ok.

> 
> >> Consider this:
> >>
> >> If the device was instantiated from a board file *or* a device tree,
> >> i2c->irq is correctly set. Hence, checking that value works in both
> >> cases.
> >>
> >> If you check the interrupts DT property, that will only work if the
> >> device was instantiated from device tree, and not if it was
> >> instantiated from a board file; the property will never exist in the
> >> board file case, and hence you'll never be able to have a board file
> >> provide an interrupt.
> >
> > The board file approach is getting deprecated for this. I Myself
> > removed board file related pdata stuff in one of the patches.
> >
> > http://www.mail-archive.com/linux-omap@xxxxxxxxxxxxxxx/msg90598.html
> >
> > So going the DeviceTree way.
> 
> Even if you're 100% sure this driver will only ever work with DT (which
> seems like a bad assumption to make no matter what the circumstance),
> it'd still be best to detect whether an IRQ was specified in a generic
> way. That way, nobody will read this driver, assume the code is
> generic, and just copy/paste it without thinking.

Ok. I understand. I will incorporate this.

Thanks,
Keerthy
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/