Message-ID: <a02d76dc-52cc-3ecc-5ef7-825c3167431a@gmail.com>
Date:   Sat, 18 Dec 2021 13:17:13 -0800
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Subject: Re: [PATCH 1/3] i2c: bcm2835: Use platform_get_irq() to get the
 interrupt
Content-Language: en-US
To:     Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>,
        Rob Herring <robh+dt@kernel.org>,
        Nicolas Saenz Julienne <nsaenz@kernel.org>,
        Ray Jui <rjui@broadcom.com>,
        Scott Branden <sbranden@broadcom.com>,
        bcm-kernel-feedback-list@broadcom.com,
        Chris Brandt <chris.brandt@renesas.com>,
        Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc:     linux-i2c@vger.kernel.org, linux-rpi-kernel@lists.infradead.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-renesas-soc@vger.kernel.org,
        Prabhakar <prabhakar.csengg@gmail.com>
References: <20211218165258.16716-1-prabhakar.mahadev-lad.rj@bp.renesas.com>
 <20211218165258.16716-2-prabhakar.mahadev-lad.rj@bp.renesas.com>
From:   Florian Fainelli <f.fainelli@gmail.com>
In-Reply-To: <20211218165258.16716-2-prabhakar.mahadev-lad.rj@bp.renesas.com>
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Precedence: bulk


On 12/18/2021 8:52 AM, 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().
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Just one nit below:
> ---
>   drivers/i2c/busses/i2c-bcm2835.c | 11 ++++-------
>   1 file changed, 4 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c
> index 37443edbf754..d63dec5f3cb1 100644
> --- a/drivers/i2c/busses/i2c-bcm2835.c
> +++ b/drivers/i2c/busses/i2c-bcm2835.c
> @@ -402,7 +402,7 @@ static const struct i2c_adapter_quirks bcm2835_i2c_quirks = {
>   static int bcm2835_i2c_probe(struct platform_device *pdev)
>   {
>   	struct bcm2835_i2c_dev *i2c_dev;
> -	struct resource *mem, *irq;
> +	struct resource *mem;
>   	int ret;
>   	struct i2c_adapter *adap;
>   	struct clk *mclk;
> @@ -452,12 +452,9 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
>   		return ret;
>   	}
>   
> -	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
> -	if (!irq) {
> -		dev_err(&pdev->dev, "No IRQ resource\n");
> -		return -ENODEV;
> -	}
> -	i2c_dev->irq = irq->start;
> +	i2c_dev->irq = platform_get_irq(pdev, 0);
> +	if (i2c_dev->irq <= 0)
> +		return i2c_dev->irq ? i2c_dev->irq : -ENXIO;

Why not just check for a negative return code and propagate it as is?
-- 
Florian