Re: [PATCH v3 1/3] device property: Add device_irq_get_byname

From: Andy Shevchenko
Date: Thu Jan 20 2022 - 09:59:44 EST


On Thu, Jan 20, 2022 at 3:45 PM Akhil R <akhilrajeev@xxxxxxxxxx> wrote:

Thanks, my comments below.

> Add device_irq_get_byname() to get an interrupt by name from both the
> ACPI table and the Device Tree.

This needs to be clarified (it's not and, but or), what about:

Add device_irq_get_byname() to get an interrupt by name from either
ACPI table or Device Tree whichever has it.

> This will allow to use 'interrupt-names' in _DSD which can be mapped to

In the ACPI case this
allow us to

> Interrupt() resource by index. The implementation is similar to
> 'interrupt-names' in the Device Tree.

...

> /**
> + * fwnode_irq_get_byname - Get IRQ from a fwnode using its name
> + * @fwnode: Pointer to the firmware node
> + * @name: IRQ name
> + *
> + * Description:
> + * Find a match to the string 'name' in the 'interrupt-names' string array

'name' --> @name

> + * in _DSD for ACPI, or of_node for device tree. Then get the Linux IRQ

Device Tree

> + * number of the IRQ resource corresponding to the index of the matched
> + * string.
> + *
> + * Return:

> + * Linux IRQ number on success
> + * Negative errno otherwise.

* Linux IRQ number on success, or negative errno otherwise.

> + */
> +int fwnode_irq_get_byname(const struct fwnode_handle *fwnode, const char *name)
> +{
> + int index;
> +
> + if (!name)
> + return -EINVAL;
> +
> + index = fwnode_property_match_string(fwnode, "interrupt-names", name);
> + if (index < 0)
> + return index;
> +
> + return fwnode_irq_get(fwnode, index);
> +}

...

> +/**
> + * device_irq_get_byname - Get IRQ of a device using interrupt name
> + * @dev: Device to get the interrupt
> + * @name: IRQ name
> + *
> + * Description:
> + * Find a match to the string 'name' in the 'interrupt-names' string array
> + * in _DSD for ACPI, or of_node for device tree. Then get the Linux IRQ
> + * number of the IRQ resource corresponding to the index of the matched
> + * string.
> + *
> + * Return:
> + * Linux IRQ number on success
> + * Negative errno otherwise.
> + */

As per above.

...

> +int device_irq_get_byname(struct device *dev, const char *name);

Since we don't have device_irq_get() perhaps we don't need this one
right now (just open code it in the caller). This will satisfy
Rafael's request.

--
With Best Regards,
Andy Shevchenko