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Date:   Tue, 10 May 2022 19:44:13 +0100
Message-ID: <875ymd6xdu.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Antonio Borneo <antonio.borneo@foss.st.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        <linux-kernel@vger.kernel.org>,
        <linux-stm32@st-md-mailman.stormreply.com>,
        <linux-arm-kernel@lists.infradead.org>,
        Pascal Paillet <p.paillet@foss.st.com>,
        Ludovic Barre <ludovic.barre@foss.st.com>,
        Loic Pallardy <loic.pallardy@foss.st.com>
Subject: Re: [PATCH 4/7] irqchip/stm32-exti: forward irq_request_resources to parent
In-Reply-To: <20220510164123.557921-4-antonio.borneo@foss.st.com>
References: <20220510164123.557921-1-antonio.borneo@foss.st.com>
        <20220510164123.557921-4-antonio.borneo@foss.st.com>
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On Tue, 10 May 2022 17:41:20 +0100,
Antonio Borneo <antonio.borneo@foss.st.com> wrote:
> 
> From: Pascal Paillet <p.paillet@foss.st.com>
> 
> Enhance stm32-exti driver to forward request_resources and
> release_resources_parent operations to parent.
> Do not use irq_request_resources_parent because it returns
> an error when the parent does not implement irq_request_resources.
> 
> Signed-off-by: Pascal Paillet <p.paillet@foss.st.com>
> Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
> ---
>  drivers/irqchip/irq-stm32-exti.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/drivers/irqchip/irq-stm32-exti.c b/drivers/irqchip/irq-stm32-exti.c
> index c8003f4f0457..3f6d524a87fe 100644
> --- a/drivers/irqchip/irq-stm32-exti.c
> +++ b/drivers/irqchip/irq-stm32-exti.c
> @@ -550,6 +550,16 @@ static void stm32_exti_h_unmask(struct irq_data *d)
>  		irq_chip_unmask_parent(d);
>  }
>  
> +static int stm32_exti_h_request_resources(struct irq_data *data)
> +{
> +	data = data->parent_data;
> +
> +	if (data->chip->irq_request_resources)
> +		return data->chip->irq_request_resources(data);
> +
> +	return 0;
> +}

Why do you need to reinvent the whole thing? Why isn't it just:

static int stm32_exti_h_request_resources(struct irq_data *data)
{
	irq_chip_request_resources_parent(data);
	return 0;
}

And this really deserves a comment. I also wonder whether we should
change this behaviour to always return 0.

	M.

-- 
Without deviation from the norm, progress is not possible.