Re: [PATCH v5] ata: pata_of_platform: Use platform_get_irq_optional() to get the interrupt

From: Damien Le Moal
Date: Mon Jan 10 2022 - 17:53:15 EST


On 2022/01/06 3:17, 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 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().
>
> Note the code does not set the IRQ flags as this is handled automatically
> for DT.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> ---
> Hi All,
>
> This patch is part of series [1]. I'll re-visit merging of pata_of_platform
> into pata_platform at later point. As my primary focus is removal of static
> setup of IRQ resource from DT core code.
>
> [1] https://patchwork.ozlabs.org/project/linux-ide/list/?series=278349
>
> v4->v5
> * Set end member of IRQ resource
> * Clear irq_res un-conditionally.
>
> Cheers,
> Prabhakar
> ---
> drivers/ata/pata_of_platform.c | 15 ++++++++++++---
> 1 file changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/ata/pata_of_platform.c b/drivers/ata/pata_of_platform.c
> index 35aa158fc976..c3a40b717dcd 100644
> --- a/drivers/ata/pata_of_platform.c
> +++ b/drivers/ata/pata_of_platform.c
> @@ -25,11 +25,12 @@ static int pata_of_platform_probe(struct platform_device *ofdev)
> struct device_node *dn = ofdev->dev.of_node;
> struct resource io_res;
> struct resource ctl_res;
> - struct resource *irq_res;
> + struct resource irq_res;
> unsigned int reg_shift = 0;
> int pio_mode = 0;
> int pio_mask;
> bool use16bit;
> + int irq;
>
> ret = of_address_to_resource(dn, 0, &io_res);
> if (ret) {
> @@ -45,7 +46,15 @@ static int pata_of_platform_probe(struct platform_device *ofdev)
> return -EINVAL;
> }
>
> - irq_res = platform_get_resource(ofdev, IORESOURCE_IRQ, 0);
> + memset(&irq_res, 0, sizeof(irq_res));
> +
> + irq = platform_get_irq_optional(ofdev, 0);
> + if (irq < 0 && irq != -ENXIO)
> + return irq;
> + if (irq > 0) {
> + irq_res.start = irq;
> + irq_res.end = irq;
> + }
>
> of_property_read_u32(dn, "reg-shift", &reg_shift);
>
> @@ -63,7 +72,7 @@ static int pata_of_platform_probe(struct platform_device *ofdev)
> pio_mask = 1 << pio_mode;
> pio_mask |= (1 << pio_mode) - 1;
>
> - return __pata_platform_probe(&ofdev->dev, &io_res, &ctl_res, irq_res,
> + return __pata_platform_probe(&ofdev->dev, &io_res, &ctl_res, irq > 0 ? &irq_res : NULL,
> reg_shift, pio_mask, &pata_platform_sht,
> use16bit);
> }

Andy,

Are you OK with this version ?

--
Damien Le Moal
Western Digital Research