Re: [PATCH v2 4/4] pmdomain: mediatek: Add power domain driver for MT8189 SoC

[Simon Horman <horms@kernel.org>]

On Fri, Sep 12, 2025 at 08:04:53PM +0800, irving.ch.lin wrote:
> From: Irving-ch Lin <irving-ch.lin@mediatek.com>
> 
> Introduce a new power domain (pmd) driver for the MediaTek mt8189 SoC.
> This driver ports and refines the power domain framework, dividing
> hardware blocks (CPU, GPU, peripherals, etc.) into independent power
> domains for precise and energy-efficient power management.
> 
> Signed-off-by: Irving-ch Lin <irving-ch.lin@mediatek.com>

...

> diff --git a/drivers/pmdomain/mediatek/mtk-scpsys.c b/drivers/pmdomain/mediatek/mtk-scpsys.c

...

> @@ -419,54 +848,145 @@ static void init_clks(struct platform_device *pdev, struct clk **clk)
>  		clk[i] = devm_clk_get(&pdev->dev, clk_names[i]);
>  }
>  
> +static int init_subsys_clks(struct platform_device *pdev,
> +			    const char *prefix, struct clk **clk)
> +{
> +	struct device_node *node = pdev->dev.of_node;
> +	u32 prefix_len, sub_clk_cnt = 0;
> +	struct property *prop;
> +	const char *clk_name;
> +
> +	if (!node) {
> +		dev_err(&pdev->dev, "Cannot find scpsys node: %ld\n",
> +			PTR_ERR(node));
> +		return PTR_ERR(node);

Hi Irving-ch,

Here node is NULL. So PTR_ERR(node) will be zero.
This is probably not what you are after here.

Flagged by Smatch

> +	}
> +
> +	prefix_len = strlen(prefix);
> +
> +	of_property_for_each_string(node, "clock-names", prop, clk_name) {
> +		if (!strncmp(clk_name, prefix, prefix_len) &&
> +		    (strlen(clk_name) > prefix_len + 1) &&
> +		    (clk_name[prefix_len] == '-')) {
> +			if (sub_clk_cnt >= MAX_SUBSYS_CLKS) {
> +				dev_err(&pdev->dev,
> +					"subsys clk out of range %d\n",
> +					sub_clk_cnt);
> +				return -EINVAL;
> +			}
> +
> +			clk[sub_clk_cnt] = devm_clk_get(&pdev->dev, clk_name);
> +
> +			if (IS_ERR(clk[sub_clk_cnt])) {
> +				dev_err(&pdev->dev,
> +					"Subsys clk get fail %ld\n",
> +					PTR_ERR(clk[sub_clk_cnt]));
> +				return PTR_ERR(clk[sub_clk_cnt]);
> +			}
> +			sub_clk_cnt++;
> +		}
> +	}
> +
> +	return sub_clk_cnt;
> +}

...