[RFC 1/2] irq_domain: Create common xlate functions that device drivers can use

[Rob Herring]

On 01/25/2012 11:59 AM, Grant Likely wrote:
> On Tue, Jan 24, 2012 at 10:35 PM, Grant Likely
> <grant.likely at secretlab.ca> wrote:
>> On Tue, Jan 24, 2012 at 6:50 PM, Rob Herring <robherring2 at gmail.com> wrote:
>>>
>>>
>>> On 01/24/2012 06:18 PM, Grant Likely wrote:
>>>> Rather than having each interrupt controller driver creating its own barely
>>>> unique .xlate function for irq_domain, create a library of translators which
>>>> any driver can use directly.
>>>>
>>>> diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
>>>> index e7379a3..5e497a0 100644
>>>> --- a/include/linux/irqdomain.h
>>>> +++ b/include/linux/irqdomain.h
>>>> @@ -110,6 +110,9 @@ struct irq_domain {
>>>>       void *host_data;
>>>>       irq_hw_number_t inval_irq;
>>>>
>>>> +     /* Data for common irq xlate functions */
>>>> +     unsigned int xlate_type;
>>>> +
>>>
>>> How does this get set? Do we want interrupt controllers messing with the
>>> domain struct directly long term?
>>
>> It defaults to IRQ_TYPE_NONE in the alloc function and drivers can
>> override it.  Alternately it could be made part of the
>> irq_domain_add() arguments, but I'm not thrilled with adding a whole
>> bunch of arguments to the function prototype.
> 
> Do you like this better (built on top of this patch)?

Yes, I think it's better.

> diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
> index ef2b1fe..7856c04 100644
> --- a/kernel/irq/irqdomain.c
> +++ b/kernel/irq/irqdomain.c
> @@ -701,12 +701,10 @@ int irq_domain_xlate_onecell(struct irq_domain
> *d, struct device_node *ctrlr,
>  			     const u32 *intspec, unsigned int intsize,
>  			     unsigned long *out_hwirq, unsigned int *out_type)
>  {
> -	if (WARN(intsize < 1, "Bad intspec for %s: intsize=%i < 1\n",
> -		 ctrlr->full_name, intsize))
> +	if (WARN_ON(intsize < 1))
>  		return -EINVAL;
> -	*out_hwirq = intspec[0];
> -	*out_type = d->xlate_type;
> -	return 0;
> +	return irq_domain_xlate_onetwocell(d, ctrlr, intspec, 1,
> +					   out_hwirq, out_type);
>  }
>  EXPORT_SYMBOL_GPL(irq_domain_xlate_onecell);
> 
> @@ -721,12 +719,10 @@ int irq_domain_xlate_twocell(struct irq_domain
> *d, struct device_node *ctrlr,
>  			const u32 *intspec, unsigned int intsize,
>  			irq_hw_number_t *out_hwirq, unsigned int *out_type)
>  {
> -	if (WARN(intsize < 2, "Bad intspec for %s: intsize=%i < 2\n",
> -		 ctrlr->full_name, intsize))
> +	if (WARN_ON(intsize < 2))
>  		return -EINVAL;
> -	*out_hwirq = intspec[0];
> -	*out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
> -	return 0;
> +	return irq_domain_xlate_onetwocell(d, ctrlr, intspec, intsize,
> +					   out_hwirq, out_type);
>  }
>  EXPORT_SYMBOL_GPL(irq_domain_xlate_twocell);
> 
> @@ -746,8 +742,7 @@ int irq_domain_xlate_onetwocell(struct irq_domain *d,
>  				const u32 *intspec, unsigned int intsize,
>  				unsigned long *out_hwirq, unsigned int *out_type)
>  {
> -	if (WARN(intsize < 1, "Bad intspec for %s: intsize=%i < 1\n",
> -		 ctrlr->full_name, intsize))
> +	if (WARN_ON(intsize < 1))
>  		return -EINVAL;
>  	*out_hwirq = intspec[0];
>  	*out_type = d->xlate_type;