[RFC 1/3] hvc_console: rework setup to replace irq functions with callbacks (not word wrapped)

[Benjamin Herrenschmidt]

On Tue, 2008-06-03 at 14:49 +0200, Christian Borntraeger wrote:
> This patch tries to change hvc_console to not use request_irq/free_irq if
> the backend does not use irqs. This allows virtio_console to use hvc_console
> without having a linker reference to request_irq/free_irq.
> 
> The irq specific code is moved to hvc_irq.c and selected by the drivers that
> use irqs (System p, System i, XEN).
> 
> I replaced "irq" with the opaque name "data". The request_irq and free_irq
> calls are replaced with notifier_add and notifier_del. I have also changed
> the code a bit to call the notifier_add and notifier_del inside the spinlock
> area as the callbacks are found via hp->ops.
> 
> Feedback is appreciated.

I haven't looked at the patch proper but I agree with the basic
premises. We routinely use hvc_console for things that don't have an
irq. In fact, David even did a backend hooking up to udbg which is
useful when bringing up weird stuffs :-)

Cheers,
Ben.