Re: [PATCH] ata: pata_of_platform: Use of_irq_to_resource() to populate IRQ resource

From: Sergey Shtylyov
Date: Fri Dec 17 2021 - 04:33:11 EST


Hello!

On 17.12.2021 3:12, Lad Prabhakar 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 bypassed the hierarchical setup and messed up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use of_irq_to_resource().

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
---
Hi,

Dropping usage of platform_get_resource() was agreed based on
the discussion [0].

[0] https://patchwork.kernel.org/project/linux-renesas-soc/
patch/20211209001056.29774-1-prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx/

Cheers,
Prabhakar
---
drivers/ata/pata_of_platform.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/ata/pata_of_platform.c b/drivers/ata/pata_of_platform.c
index 35aa158fc976..557f349eb533 100644
--- a/drivers/ata/pata_of_platform.c
+++ b/drivers/ata/pata_of_platform.c
[...]
@@ -45,7 +47,9 @@ static int pata_of_platform_probe(struct platform_device *ofdev)
return -EINVAL;
}
- irq_res = platform_get_resource(ofdev, IORESOURCE_IRQ, 0);
+ irq = of_irq_to_resource(dn, 0, &irq_res);

Why not use platform_get_irq_optional()?

+ if (irq <= 0 && irq != -ENXIO)
+ return irq ? irq : -ENXIO;
of_property_read_u32(dn, "reg-shift", &reg_shift);
[...]

MBR, Sergey