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

From: J, KEERTHY
Date: Tue Jun 18 2013 - 12:55:11 EST


Hi Stephen,

> -----Original Message-----
> From: Stephen Warren [mailto:swarren@xxxxxxxxxxxxx]
> Sent: Tuesday, June 18, 2013 9:22 PM
> 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 04:01 AM, J Keerthy wrote:
> > Check if interrupts property exists and then only request irq.
> > On some boards INT line might not be connected to a valid irq line on
> > the application processor. Hence keeping a check before requesting
> > irq.
>
> When there is no interrupts property, surely i2c->irq == 0, which is an
> invalid IRQ, and hence there's no need to check this before copying the
> value?

The intent here is NOT to request irq with 0 or Invalid IRQ. The board
File will not populate the interrupts entry if the INT line is not
Connected. Hence the patch checks for the 'interrupts' property.

This is essential since I do not want the probe to return error
Just because the i2c->irq == 0. The explicit check for the property
Ensures that the board does not have the INT line connected to
A valid interrupt line on the other side.

>
> In other words, I think this whole patch could just be:
>
> + palmas->irq = i2c->irq;
>
> right?

Just this will cause a probe failure. That is not what is needed.
Instead the probe should continue skipping irq part.

Regards,
Keerthy
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