Re: [PATCH 06/13] media: davinci: vpif: Use platform_get_irq_optional() to get the interrupt

From: Andy Shevchenko
Date: Sat Dec 25 2021 - 12:33:01 EST


On Sat, Dec 25, 2021 at 3:04 AM Lad Prabhakar
<prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> wrote:
>
> platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
> allocation of IRQ resources in DT core code, this causes an issue
> when using hierarchical interrupt domains using "interrupts" property
> in the node as this bypasses the hierarchical setup and messes up the
> irq chaining.
>
> In preparation for removal of static setup of IRQ resource from DT core
> code use platform_get_irq_optional().
>
> Also this patch propagates error code in case devm_request_irq()
> fails instead of returing -EINVAL.

returning

...

> + res_irq->flags = IORESOURCE_IRQ | irq_get_trigger_type(irq);
> + res_irq->start = irq;
> + res_irq->end = irq;
> + res_irq->name = dev_of_node(&pdev->dev) ? of_node_full_name(pdev->dev.of_node) : NULL;

If you convert DEFINE_RES_NAMED() to return a compound literal, then
you may use it here like

res_irq = DEFINE_RES_NAMED(...);

or even do like this

if (dev_of_node(...))
res_irq = DEFINE_RES_IRQ_NAMED(...)
else
res_irq = DEFINE_RES_IRQ(...);
res_irq->flags |= irq_get_trigger_type(irq);

I'm not sure why you can't simply use the NAMED variant in both cases
(yes, I see that of_node_full_name() will return something, not NULL).

...

> + while ((err = platform_get_irq_optional(pdev, res_idx)) != -ENXIO) {
> + if (err < 0)
> + goto vpif_unregister;

Needs a better error checking, i.e. consider 0 as no-IRQ (equivalent
to -ENXIO (note, OF code never returns 0 as valid vIRQ).

> res_idx++;
> }

...

> + while ((err = platform_get_irq_optional(pdev, res_idx)) != -ENXIO) {
> + if (err < 0)
> + goto vpif_unregister;

Ditto.

--
With Best Regards,
Andy Shevchenko