[PATCH] of/irq: Handle explicit interrupt parent

[Marek Szyprowski]

On 19.11.2025 14:19, Geert Uytterhoeven wrote:
> If an interrupt controller is used as a proxy, it may have an
> "interrupt-parent" property, but lack "interrupts" and
> "interrupts-extended" properties.  In that case, the "interrupt-parent"
> property in the interrupt controller node is ignored, causing the
> interrupt controller to fail to probe, and leading to system boot
> failures or crashes.
>
> Fix this by also considering an explicit "interrupt-parent" property in
> the interrupt controller node itself.
>
> Fixes: 1b1f04d8271e7ba7 ("of/irq: Ignore interrupt parent for nodes without interrupts")
> Reported-by: Marek Szyprowski <m.szyprowski at samsung.com>
> Closes: https://lore.kernel.org/20251118115037.1866871-1-m.szyprowski@samsung.com
> Reported-by: Mark Brown <broonie at kernel.org>
> Closes: https://lore.kernel.org/b037f67a-b241-4689-9914-57ff578c1454@sirena.org.uk
> Signed-off-by: Geert Uytterhoeven <geert+renesas at glider.be>

This fixes the issue observed on 32bit Samsung Exynos based boards.

Tested-by: Marek Szyprowski <m.szyprowski at samsung.com>

> ---
>   drivers/of/irq.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/drivers/of/irq.c b/drivers/of/irq.c
> index a68272db9879bedf..f374d8b212b8669c 100644
> --- a/drivers/of/irq.c
> +++ b/drivers/of/irq.c
> @@ -685,6 +685,8 @@ void __init of_irq_init(const struct of_device_id *matches)
>   		desc->interrupt_parent = of_parse_phandle(np, "interrupts-extended", 0);
>   		if (!desc->interrupt_parent && of_property_present(np, "interrupts"))
>   			desc->interrupt_parent = of_irq_find_parent(np);
> +		else if (!desc->interrupt_parent)
> +			desc->interrupt_parent = of_parse_phandle(np, "interrupt-parent", 0);
>   		if (desc->interrupt_parent == np) {
>   			of_node_put(desc->interrupt_parent);
>   			desc->interrupt_parent = NULL;

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland