linux-kernel - Re: [PATCH v2 02/12] PCI: brcmstb: Use "clk

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Message-ID: <45fdcd29-adb1-40eb-9f17-8c1ef8fde0d4@suse.de>
Date: Thu, 4 Jul 2024 15:53:58 +0300
From: Stanimir Varbanov <svarbanov@...e.de>
To: Jim Quinlan <james.quinlan@...adcom.com>, linux-pci@...r.kernel.org,
 Nicolas Saenz Julienne <nsaenz@...nel.org>,
 Bjorn Helgaas <bhelgaas@...gle.com>,
 Lorenzo Pieralisi <lorenzo.pieralisi@....com>,
 Cyril Brulebois <kibi@...ian.org>, Stanimir Varbanov <svarbanov@...e.de>,
 bcm-kernel-feedback-list@...adcom.com, jim2101024@...il.com
Cc: Florian Fainelli <florian.fainelli@...adcom.com>,
 Lorenzo Pieralisi <lpieralisi@...nel.org>,
 Krzysztof Wilczyński <kw@...ux.com>,
 Rob Herring <robh@...nel.org>,
 "moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE"
 <linux-rpi-kernel@...ts.infradead.org>,
 "moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE"
 <linux-arm-kernel@...ts.infradead.org>,
 open list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2 02/12] PCI: brcmstb: Use "clk_out" error path label

Hi Jim,

On 7/3/24 21:02, Jim Quinlan wrote:
> Instead of invoking "clk_disable_unprepare(pcie->clk)" in
> a number of error paths, we can just use a "clk_out" label
> and goto the label after setting the return value.
> 
> Signed-off-by: Jim Quinlan <james.quinlan@...adcom.com>
> ---
>  drivers/pci/controller/pcie-brcmstb.c | 18 +++++++++++-------
>  1 file changed, 11 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
> index c08683febdd4..c2eb29b886f7 100644
> --- a/drivers/pci/controller/pcie-brcmstb.c
> +++ b/drivers/pci/controller/pcie-brcmstb.c
> @@ -1620,24 +1620,25 @@ static int brcm_pcie_probe(struct platform_device *pdev)
>  	}
>  	pcie->rescal = devm_reset_control_get_optional_shared(&pdev->dev, "rescal");
>  	if (IS_ERR(pcie->rescal)) {
> -		clk_disable_unprepare(pcie->clk);
> -		return PTR_ERR(pcie->rescal);
> +		ret = PTR_ERR(pcie->rescal);
> +		goto clk_out;
>  	}
>  	pcie->perst_reset = devm_reset_control_get_optional_exclusive(&pdev->dev, "perst");
>  	if (IS_ERR(pcie->perst_reset)) {
> -		clk_disable_unprepare(pcie->clk);
> -		return PTR_ERR(pcie->perst_reset);
> +		ret = PTR_ERR(pcie->perst_reset);
> +		goto clk_out;
>  	}
>  

	ret = clk_prepare_enable(pcie->clk);

Have you considered enabling pcie->clk clock here ^^^ and avoid jumping
to clk_out label?

Basically, it'd be easier from error-path POV to get all required
resources and just after that start the initialization sequence of pcie
controller.

~Stan

>  	ret = reset_control_reset(pcie->rescal);
> -	if (ret)
> +	if (ret) {
>  		dev_err(&pdev->dev, "failed to deassert 'rescal'\n");
> +		goto clk_out;
> +	}
>  
>  	ret = brcm_phy_start(pcie);
>  	if (ret) {
>  		reset_control_rearm(pcie->rescal);
> -		clk_disable_unprepare(pcie->clk);
> -		return ret;
> +		goto clk_out;
>  	}
>  
>  	ret = brcm_pcie_setup(pcie);
> @@ -1676,6 +1677,9 @@ static int brcm_pcie_probe(struct platform_device *pdev)
>  
>  	return 0;
>  
> +clk_out:
> +	clk_disable_unprepare(pcie->clk);
> +	return ret;
>  fail:
>  	__brcm_pcie_remove(pcie);
>  	return ret;