Re: OMAP: DSS2: Common IRQ handler for all OMAPs

Felipe Balbi
2011-02-15T08:23:59Z

Hi,

On Tue, Feb 15, 2011 at 01:50:49PM +0530, archit taneja wrote:
> >yes it is. Then it makes sense to have an irq_chip for those two irqs, I
> >think.
> >
> >/proc/interrupt will reflect how the hardware works (DSI and DISPC IRQs
> >being handled by DSS), both dsi and dispc can use normal request_irq()
> >without setting IRQF_SHARED, etc etc. All you need to do is:
> >
> >static struct irq_chip dss_irq_chip = {
> > .name = "DSS",
> > .irq_bus_lock = dss_bus_lock,
> > .irq_bus_sync_unlock = dss_bus_sync_unlock,
> > .irq_mask = dss_irq_mask,
> > .irq_unmask = dss_irq_unmask,
> > .irq_ack = dss_irq_ack,
> >};
> >
> >then, somewhere during probe() you have to:
> >
> >for (irq = irq_base; irq< irq_end; irq++) {
> >#ifdef CONFIG_ARM
> > set_irq_flags(irq, IRQF_VALID)
> >#else
> > set_irq_noprobe(irq);
> >#endif
> >
> > set_irq_data(irq, dss_device_structure_pointer);
> > set_irq_chip_and_handler(irq,&dss_irq_chip,
> > handle_simple_irq);
> >}
> >
> >and on exit() you just need to cleanup:
> >
> >for (irq = irq_base; irq< irq_end; irq++) {
> >#ifdef CONFIG_ARM
> > set_irq_flags(irq, 0)
> >#endif
> >
> > set_irq_chip_and_handler(irq, NULL, NULL);
> > set_irq_data(irq, NULL);
> >}
> >
>
> Thanks for the info, but this seems to be suitable for the case
> when there are multiple irq events coming from the same interrupt
> line. On OMAP4 we have 4 different IRQ lines going to ARM, i.e 4
> lines defined in irqs-44xx.h.

do you have 4 lines for 4 different modules ? If so, what's the problem
here ? The irq_chip you're using is INTC

> We are looking for a common irq handler located somewhere centrally,
> and each module can hook their irq line to this handler.
>
> Does irq_chip do this? what does irq_base and irq_end signify?

I guess it can't do that, no. irq_base is the starting number for this
irq_chip's IRQ and irq_end is irq_base + number_of_irqs.

--
balbi