Re: [PATCH v1 5/6] platform: Modify platform_get_irq_optional() to use resource

From: Andy Shevchenko
Date: Wed Dec 13 2023 - 14:53:25 EST


On Wed, Dec 13, 2023 at 11:00:23AM -0700, Mark Hasemeyer wrote:
> Unify handling of ACPI, GPIO, devictree, and platform resource
> interrupts in platform_get_irq_optional(). Each of these subsystems
> provide their own apis which provide IRQ information as a struct
> resource. This simplifies the logic of the function and allows callers
> to get more information about the irq by looking at the resource flags.

IRQ

> For example, whether or not an irq is wake capable.

IRQ

> Rename the function to platform_get_irq_resource() to better describe
> the function's new behavior.

...

> - * platform_get_irq_optional - get an optional IRQ for a device
> + * platform_get_irq_resource - get an IRQ for a device and populate resource struct
> * @dev: platform device
> * @num: IRQ number index
> + * @r: pointer to resource to populate with irq information. It is not modified on failure.

IRQ

It's inconsistent with just a few lines above!

Also same comment about second remark, no need to have it. It's implied.

...

> + *r = (struct resource)DEFINE_RES_IRQ(ret);

Why is the annotation needed?

...

> - struct resource *r;
> + struct resource *platform_res;
>
> if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) {
> - ret = of_irq_get(dev->dev.of_node, num);
> + ret = of_irq_to_resource(dev->dev.of_node, num, r);
> if (ret > 0 || ret == -EPROBE_DEFER)
> goto out;
> }


> + if (has_acpi_companion(&dev->dev)) {
> + ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
> + if (!ret || ret == -EPROBE_DEFER) {
> + ret = ret ?: r->start;
> + goto out;
> + }
> + }

Consider combine the above to use fwnode_irq_get() in the separate prerequisite
change.

...

> + /*
> + * The resources may pass trigger flags to the irqs that need
> + * to be set up. It so happens that the trigger flags for
> + * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER*
> + * settings.
> + */
> + if (ret > 0 && r->flags & IORESOURCE_BITS) {
> + struct irq_data *irqd;

> + irqd = irq_get_irq_data(r->start);
> + if (!irqd)
> + ret = -ENXIO;

> + else

Redundant.

Just return directly from the above.

> + irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS);

NIH resource_type().

> + }
> return ret;

...

What you need to add to all the functions is either
- check that resource pointer is not NULL, and/or
- documentation that explain this requirement or mark it optional
(but second seems nonsense)

--
With Best Regards,
Andy Shevchenko