[PATCH v3 1/7] genirq: generic chip: export irq_map_generic_chip function

[boris.brezillon@free-electrons.com (Boris BREZILLON)]

On 23/06/2014 15:07, Jason Cooper wrote:
> On Sun, Jun 22, 2014 at 09:59:44AM +0200, Boris BREZILLON wrote:
>> On 22/06/2014 01:51, Jason Cooper wrote:
>>> On Fri, Jun 20, 2014 at 05:01:21PM +0200, Boris BREZILLON wrote:
>>>> Export the generic irq map function in order to provide irq_domain ops with
>>>> generic mapping and specific of xlate function (needed by the new atmel
>>>> AIC driver).
>>>>
>>>> Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
>>>> ---
>>>>  include/linux/irq.h       | 2 ++
>>>>  kernel/irq/generic-chip.c | 5 +++--
>>>>  2 files changed, 5 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/include/linux/irq.h b/include/linux/irq.h
>>>> index 0d998d8..62af592 100644
>>>> --- a/include/linux/irq.h
>>>> +++ b/include/linux/irq.h
>>>> @@ -771,6 +771,8 @@ void irq_gc_eoi(struct irq_data *d);
>>>>  int irq_gc_set_wake(struct irq_data *d, unsigned int on);
>>>>  
>>>>  /* Setup functions for irq_chip_generic */
>>>> +int irq_map_generic_chip(struct irq_domain *d, unsigned int virq,
>>>> +			 irq_hw_number_t hw_irq);
>>>>  struct irq_chip_generic *
>>>>  irq_alloc_generic_chip(const char *name, int nr_ct, unsigned int irq_base,
>>>>  		       void __iomem *reg_base, irq_flow_handler_t handler);
>>>> diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c
>>>> index 452d6f2..cf80e7b 100644
>>>> --- a/kernel/irq/generic-chip.c
>>>> +++ b/kernel/irq/generic-chip.c
>>>> @@ -341,8 +341,8 @@ static struct lock_class_key irq_nested_lock_class;
>>>>  /*
>>>>   * irq_map_generic_chip - Map a generic chip for an irq domain
>>>>   */
>>>> -static int irq_map_generic_chip(struct irq_domain *d, unsigned int virq,
>>>> -				irq_hw_number_t hw_irq)
>>>> +int irq_map_generic_chip(struct irq_domain *d, unsigned int virq,
>>>> +			 irq_hw_number_t hw_irq)
>>>>  {
>>>>  	struct irq_data *data = irq_get_irq_data(virq);
>>>>  	struct irq_domain_chip_generic *dgc = d->gc;
>>>> @@ -394,6 +394,7 @@ static int irq_map_generic_chip(struct irq_domain *d, unsigned int virq,
>>>>  	irq_modify_status(virq, dgc->irq_flags_to_clear, dgc->irq_flags_to_set);
>>>>  	return 0;
>>>>  }
>>>> +EXPORT_SYMBOL_GPL(irq_map_generic_chip);
>>>>  
>>>>  struct irq_domain_ops irq_generic_chip_ops = {
>>>>  	.map	= irq_map_generic_chip,
>>> Why can't you use irq_generic_chip_ops.map in your code and avoid this
> s/code/declaration/, sorry for the misunderstanding.
>
>>> patch entirely?
>> Because in this case I'll have to remove constness from my
>> irq_domain_ops struct and initialize it in my init function.
>> This is not a big concern, but in general I tend to declare ops struct
>> with a const constraint.
> /*
>  * We're the only user of irq_map_generic_chip() who
>  * doesn't also use irq_domain_xlate_onetwocell()
>  */
> static const struct irq_domain_ops aic_irq_ops = {
> 	.map    = irq_generic_chip_ops.map,
>         .xlate  = aic_irq_domain_xlate,
> };
>
> Wouldn't work?

No, it fails  with :

"error: initializer element is not constant"


>
>> Tell me if you still want me to drop this patch and rework my init process.
> If the above is satisfactory for you, please do so.  If we get a few
> more chips that need one function, but not the other, then we'll revisit
> what we're exporting.  The comment should bring the issue up in a
> future grep.
>
> thx,
>
> Jason.

-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com