Re: [PATCH] genirq: Don't return error on missing optional irq_request_resources()

From: Antonio Borneo <antonio.borneo@foss.st.com>
To: Thomas Gleixner <tglx@linutronix.de>,
	Marc Zyngier <maz@kernel.org>, <linux-kernel@vger.kernel.org>
Cc: <linux-stm32@st-md-mailman.stormreply.com>
Subject: Re: [PATCH] genirq: Don't return error on missing optional irq_request_resources()
Date: Mon, 4 Jul 2022 14:53:36 +0200	[thread overview]
Message-ID: <4a57677268ac356a006ee35f73ceacdf49ae4221.camel@foss.st.com> (raw)
In-Reply-To: <20220512160544.13561-1-antonio.borneo@foss.st.com>

On Thu, 2022-05-12 at 18:05 +0200, Antonio Borneo wrote:
> Function irq_chip::irq_request_resources() is reported as optional
> in the declaration of struct irq_chip.
> If the parent irq_chip does not implement it, we should ignore it
> and return.
> 
> Don't return error if the functions is missing.
> 
> Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
> ---
> 
> As follow-up of discussion in
> https://lore.kernel.org/lkml/875ymd6xdu.wl-maz@kernel.org/
> here is a proposal for changing the returned value.
> 
> A similar issue is present for the optional function
> irq_set_vcpu_affinity(), to be covered separately, if needed.

Gentle ping for this patch.
Does it match the expected behaviour for an optional function?

Thanks,
Antonio

> 
> ---
>  kernel/irq/chip.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
> index 54af0deb239b..eb921485930f 100644
> --- a/kernel/irq/chip.c
> +++ b/kernel/irq/chip.c
> @@ -1513,7 +1513,8 @@ int irq_chip_request_resources_parent(struct
> irq_data *data)
>         if (data->chip->irq_request_resources)
>                 return data->chip->irq_request_resources(data);
>  
> -       return -ENOSYS;
> +       /* no error on missing optional
> irq_chip::irq_request_resources */
> +       return 0;
>  }
>  EXPORT_SYMBOL_GPL(irq_chip_request_resources_parent);
>  
> 
> base-commit: c5eb0a61238dd6faf37f58c9ce61c9980aaffd7a