quoted text > This patch lets interrupt handler functions have their natural type
> (ie. exactly match the data pointer type); for transition it allows
> the old irq_handler_t type as well.
>
> To do this it uses a gcc extension, cast-to-union, which allows a type
> to be cast to any type within the union. When used in a wrapper
> macro, it's a simple way of allowing one of several types.
>
> (Some drivers now need to be cleaned up to compile, previous patch).
>
> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
> ---
> include/linux/interrupt.h | 17 +++++++++++++++--
> include/linux/kernel.h | 7 +++++++
> kernel/irq/devres.c | 10 +++++-----
> kernel/irq/manage.c | 6 +++---
> 4 files changed, 30 insertions(+), 10 deletions(-)
>
> diff -r 0fe1a980708b include/linux/interrupt.h
> --- a/include/linux/interrupt.h Thu Jan 17 14:48:56 2008 +1100
> +++ b/include/linux/interrupt.h Thu Jan 17 15:42:01 2008 +1100
> @@ -69,13 +69,26 @@ struct irqaction {
> };
>
> extern irqreturn_t no_action(int cpl, void *dev_id);
> -extern int __must_check request_irq(unsigned int, irq_handler_t handler,
> +
> +/* Typesafe version of request_irq. Also takes old-style void * handlers. */
> +#define request_irq(irq, handler, flags, name, dev_id) \
> + __request_irq((irq), \
> + check_either_type((handler), irq_handler_t, \
> + int (*)(int, typeof(dev_id))), \
> + (flags), (name), (dev_id))
> +
> +extern int __must_check __request_irq(unsigned int, irq_handler_t handler,
> unsigned long, const char *, void *);
> extern void free_irq(unsigned int, void *);
>
> struct device;
>
> -extern int __must_check devm_request_irq(struct device *dev, unsigned int irq,
> +#define devm_request_irq(dev, irq, handler, flags, name, dev_id) \
> + __devm_request_irq((dev), (irq), \
> + check_either_type((handler), irq_handler_t, \
> + int (*)(int, typeof(dev_id))), \
> + (flags), (name), (dev_id))
> +extern int __must_check __devm_request_irq(struct device *dev, unsigned int irq,
> irq_handler_t handler, unsigned long irqflags,
> const char *devname, void *dev_id);
This is ugly and unnecessary.
Anything that does not use irq_handler_t is broken and should be fixed
(as noted in last email, I think I've covered all this driver work already)
And if by definition everything uses irq_handler_t, there is no need for
any of this "check_either_type" silliness.
Jeff
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