Subject: Re: powerpc/8xx: Adding support of IRQ in MPC8xx GPIO

From: Scott Wood <[email-masked]>
Date: Mon, 01 May 2017 13:14:21 -0500

On Mon, 2017-05-01 at 09:46 +0200, christophe leroy wrote:
> 
> Le 30/04/2017 à 08:48, Scott Wood a écrit :
> > On Thu, Mar 09, 2017 at 10:42:04AM +0100, Christophe Leroy wrote:
> > > 
> > > @@ -625,6 +641,14 @@ int cpm1_gpiochip_add16(struct device_node *np)
> > > 
> > >  	spin_lock_init(&cpm1_gc->lock);
> > > 
> > > +	if (!of_property_read_u16(np, "interrupts-mask", &mask)) {
> > > +		int i, j;
> > > +
> > > +		for (i = 0, j = 0; i < 16; i++)
> > > +			if (mask & (1 << (15 - i)))
> > > +				cpm1_gc->irq[i] =
> > > irq_of_parse_and_map(np, j++);
> > > +	}
> > 
> > Do we really need to use MSB-first bit numbering here?
> 
> Well, I think it is better to keep the GPIOs in the same order as in the 
> CPM1 registers, like everywhere else in that driver, isn't it ?
> 
> The registers have GPIO 0 in the MSB and GPIO15 in the LSB.

OK, if there's a specific register this is reflecting that's reasonable.

-Scott