Re: [PATCH] mfd: db8500-prcmu: fix irqdomain usage

[Lee Jones <lee.jones@linaro.org>]

On Thu, 20 Dec 2012, Grant Likely wrote:

> On Wed, 19 Dec 2012 15:42:41 +0100, Linus Walleij <linus.walleij@stericsson.com> wrote:
> > From: Linus Walleij <linus.walleij@linaro.org>
> > 
> > This fixes two issues with the DB8500 PRCMU irqdomain:
> > - You have to state the irq base 0 to get a linear domain
> >   for the DT case from irq_domain_add_simple()
> > - The irqdomain was not used to translate the initial irq
> >   request using irq_create_mapping() making the linear
> >   case fail as it was lacking a proper descriptor.
> > 
> > I took this opportunity to fix two lines of whitespace
> > errors in related code as I was anyway messing around with
> > it.
> > 
> > Cc: stable@kernel.org
> > Cc: Lee Jones <lee.jones@linaro.org>
> > Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> > ---
> > Hi Sam, this is a regression and as such should go into the
> > -rc series. As you can see I also added the Cc: stable tag.
> > 
> > Yours,
> > Linus Walleij
> > ---
> >  drivers/mfd/db8500-prcmu.c | 8 ++++----
> >  1 file changed, 4 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/mfd/db8500-prcmu.c b/drivers/mfd/db8500-prcmu.c
> > index dc8826d..fcac8e0 100644
> > --- a/drivers/mfd/db8500-prcmu.c
> > +++ b/drivers/mfd/db8500-prcmu.c
> > @@ -2524,7 +2524,7 @@ static bool read_mailbox_0(void)
> >  
> >  		for (n = 0; n < NUM_PRCMU_WAKEUPS; n++) {
> >  			if (ev & prcmu_irq_bit[n])
> > -				generic_handle_irq(IRQ_PRCMU_BASE + n);
> > +				generic_handle_irq(irq_create_mapping(db8500_irq_domain,n));
> 
> This looks wrong. It probably works at the moment, but calling
> irq_create_mapping when trying to process an IRQ is backwards. There
> certainly shouldn't be any processing of an irq that isn't already
> mapped. irq_find_mapping() should be used instead.

But irq_create_mapping() calls irq_find_mapping() if the irq is
already mapped? Or are you saying that if it isn't already mapped
then there is an issue somewhere else earlier in the code?

-- 
Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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