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

[Grant Likely <grant.likely@secretlab.ca>]

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.

g.