Re: [PATCH v2] memory: atmel-ebi: Disable SMC clock on probe failure

[Alexandre Belloni <alexandre.belloni@bootlin.com>]

Hi,

On 01/11/2026 20:07:34+0100, Krzysztof Kozlowski wrote:
> Unprepare and drop the SMC clock reference, if probe fails to avoid
> resource leakage e.g. during probe deferral.
> 
> There is no remove() callback, presumably on purpose so only error paths
> are handled.
> 
> Cc: <stable@vger.kernel.org>
> Fixes: 87108dc78eb8 ("memory: atmel-ebi: Enable the SMC clock if specified")
> Reported-by: Wentao Liang <vulab@iscas.ac.cn>
> Closes: https://lore.kernel.org/all/20260917101623.2146392-1-vulab@iscas.ac.cn/
> Reported-by: Sashiko <sashiko-bot@kernel.org>
> Closes: https://sashiko.dev/#/bug/linux-8e236c81-01b2-4274-a213-11c3f31acfc2
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
> 
> ---
> 
> I independently developed the patch and then checked the queue with
> pending work of iscas. That one has issues and other complains from me,
> so only credits for the report.
> 
> Changes in v2:
> 1. Handle of_platform_populate() error.
> ---
>  drivers/memory/atmel-ebi.c | 27 ++++++++++++++++++++-------
>  1 file changed, 20 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/memory/atmel-ebi.c b/drivers/memory/atmel-ebi.c
> index 1e8e8aba2542..7dc2f7add1b1 100644
> --- a/drivers/memory/atmel-ebi.c
> +++ b/drivers/memory/atmel-ebi.c
> @@ -562,7 +562,7 @@ static int atmel_ebi_probe(struct platform_device *pdev)
>  	}
>  	ret = clk_prepare_enable(ebi->smc.clk);
>  	if (ret)
> -		return ret;
> +		goto err_put_clk;
>  

Couldn't we simply devm_clk_get_enabled() ?

>  	/*
>  	 * The sama5d3 does not provide an EBICSA register and thus does need
> @@ -572,14 +572,16 @@ static int atmel_ebi_probe(struct platform_device *pdev)
>  		ebi->regmap =
>  			syscon_regmap_lookup_by_phandle(np,
>  							ebi->caps->regmap_name);
> -		if (IS_ERR(ebi->regmap))
> -			return PTR_ERR(ebi->regmap);
> +		if (IS_ERR(ebi->regmap)) {
> +			ret = PTR_ERR(ebi->regmap);
> +			goto err_disable_clk;
> +		}
>  	}
>  
>  	ret = of_property_read_u32(np, "#address-cells", &val);
>  	if (ret) {
>  		dev_err(dev, "missing #address-cells property\n");
> -		return ret;
> +		goto err_disable_clk;
>  	}
>  
>  	reg_cells = val;
> @@ -587,7 +589,7 @@ static int atmel_ebi_probe(struct platform_device *pdev)
>  	ret = of_property_read_u32(np, "#size-cells", &val);
>  	if (ret) {
>  		dev_err(dev, "missing #address-cells property\n");
> -		return ret;
> +		goto err_disable_clk;
>  	}
>  
>  	reg_cells += val;
> @@ -603,11 +605,22 @@ static int atmel_ebi_probe(struct platform_device *pdev)
>  
>  			ret = atmel_ebi_dev_disable(ebi, child);
>  			if (ret)
> -				return ret;
> +				goto err_disable_clk;
>  		}
>  	}
>  
> -	return of_platform_populate(np, NULL, NULL, dev);
> +	ret = of_platform_populate(np, NULL, NULL, dev);
> +	if (ret)
> +		goto err_disable_clk;
> +
> +	return 0;
> +
> +err_disable_clk:
> +	clk_disable_unprepare(ebi->smc.clk);
> +err_put_clk:
> +	clk_put(ebi->smc.clk);
> +
> +	return ret;
>  }
>  
>  static __maybe_unused int atmel_ebi_resume(struct device *dev)
> -- 
> 2.53.0
> 

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com