Re: SA_TRIGGER_* vs. SA_SAMPLE_RANDOM

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

> We have the same hassle with SA_INTERRUPT. The question arises, if we
> should move the SA_XX flags for interrupts completely out of the signal
> SA name space. Rename to IRQ_xxx and put them into interrupt.h.

Agreed. In addition, if you look specifically at triggers, I've seen so
far:

 - The new SA_* trigger stuff
 - The IRQ_TYPE_* stuff
 - The definitions of bits in struct resource of interrupts in ioport.h
 - The old IRQ_LEVEL
 - Various arch specific things that duplicate it again

In addition, it's different bits with different organisation (for
example, the IRQ_TYPE can express dual edge), etc... 

In my new powerpc IRQ rework, I'm wiping out our own definitions for
triggers and using IRQ_TYPE_* accross the range. I'm howveer not using
the SA_* stuff at all at this point (that is, I'm neither converting the
trigger type of a given interrupt to SA_* and putting it in the
action/desc, nor honoring the SA_* triggers passed in request_irq at
this point). It might be nice to do so, but I find that there is just
way too much confusion at the moment.

Ben.