Re: [PATCH] iommu/mediatek-v1: Fix an error handling path in mtk_iommu_v1_probe()

[Matthias Brugger <matthias.bgg@gmail.com>]

On 19/12/2022 19:06, Christophe JAILLET wrote:
> A clk, prepared and enabled in mtk_iommu_v1_hw_init(), is not released in
> the error handling path of mtk_iommu_v1_probe().
> 
> Add the corresponding clk_disable_unprepare(), as already done in the
> remove function.
> 
> Fixes: b17336c55d89 ("iommu/mediatek: add support for mtk iommu generation one HW")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>

> ---
> Another option would be to use devm_clk_get_enabled(). This would save a
> few LoC in mtk_iommu_v1_hw_init() and in the remove function.
> However, it would change the order of function calls in the remove function
> so I leave it as-is.
> Let me know if it is fine and if you prefer this alternative.
> ---
>   drivers/iommu/mtk_iommu_v1.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c
> index 69682ee068d2..ca581ff1c769 100644
> --- a/drivers/iommu/mtk_iommu_v1.c
> +++ b/drivers/iommu/mtk_iommu_v1.c
> @@ -683,7 +683,7 @@ static int mtk_iommu_v1_probe(struct platform_device *pdev)
>   	ret = iommu_device_sysfs_add(&data->iommu, &pdev->dev, NULL,
>   				     dev_name(&pdev->dev));
>   	if (ret)
> -		return ret;
> +		goto out_clk_unprepare;
>   
>   	ret = iommu_device_register(&data->iommu, &mtk_iommu_v1_ops, dev);
>   	if (ret)
> @@ -698,6 +698,8 @@ static int mtk_iommu_v1_probe(struct platform_device *pdev)
>   	iommu_device_unregister(&data->iommu);
>   out_sysfs_remove:
>   	iommu_device_sysfs_remove(&data->iommu);
> +out_clk_unprepare:
> +	clk_disable_unprepare(data->bclk);
>   	return ret;
>   }
>