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References: <20220111194014.5908-1-prabhakar.mahadev-lad.rj@bp.renesas.com>
In-Reply-To: <20220111194014.5908-1-prabhakar.mahadev-lad.rj@bp.renesas.com>
From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Wed, 12 Jan 2022 13:32:37 +0200
Message-ID: <CAHp75VdL_v3vZwQfCqNUwg3oQbvWpq4HCL2KGbaob88-4w9RNw@mail.gmail.com>
Subject: Re: [PATCH v3] media: davinci: vpif: Use platform_get_irq_optional()
 to get the interrupt
To:     Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Cc:     Hans Verkuil <hverkuil-cisco@xs4all.nl>,
        "Lad, Prabhakar" <prabhakar.csengg@gmail.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Linux Media Mailing List <linux-media@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Tue, Jan 11, 2022 at 9:40 PM Lad Prabhakar
<prabhakar.mahadev-lad.rj@bp.renesas.com> 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().
>
> While at it, propagate error code in case devm_request_irq() fails
> instead of returning -EINVAL.

...

> +       while (1) {

The infinite loop use is discouraged.

> +               int irq;
> +
> +               err = platform_get_irq_optional(pdev, res_idx);
> +               if (err < 0 && err != -ENXIO)
> +                       goto vpif_unregister;
> +               if (err > 0)
> +                       irq = err;
> +               else
> +                       break;
> +
> +               err = devm_request_irq(&pdev->dev, irq, vpif_channel_isr,
> +                                      IRQF_SHARED, VPIF_DRIVER_NAME,
> +                                      (void *)(&vpif_obj.dev[res_idx]->channel_id));
> +               if (err)
>                         goto vpif_unregister;
> -               }
>                 res_idx++;
>         }

Slightly better

  do {
  ...
  } while (++res_idx);

...

> +       while (1) {

Ditto.

-- 
With Best Regards,
Andy Shevchenko