isoc: mediatek: Check for error clk pointer

Commit Message

Jiasheng Jiang Dec. 17, 2021, 5:30 p.m. UTC

For the devm_clk_get() may fail and return the error pointer, it might
be better to check the return value in order to avoid the use of it.
Thus, we return the error code if fail and 0 if not.
And in init_scp() checking the return value of the init_clks().

Fixes: 6078c651947a ("soc: mediatek: Refine scpsys to support multiple platform")
Signed-off-by: Jiasheng Jiang <[e-mail]>
---
 drivers/soc/mediatek/mtk-scpsys.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

Comments

Mark Brown Dec. 21, 2021, 5:57 p.m. UTC | #1

On Sat, Dec 18, 2021 at 01:30:05AM +0800, Jiasheng Jiang wrote:

> +	for (i = CLK_NONE + 1; i < CLK_MAX; i++) {
>  		clk[i] = devm_clk_get(&pdev->dev, clk_names[i]);
> +		if (IS_ERR(clk[i]))
> +			return PTR_ERR(clk[i]);

This now pays attention to the error code here which is good but...

> -	init_clks(pdev, clk);
> +	ret = init_clks(pdev, clk);
> +	if (ret)
> +		return ERR_PTR(-ENOMEM);

...then discards it here with a random most likely inappropriate error
code.

Patch

diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c
index ca75b14931ec..abb0866681df 100644
--- a/drivers/soc/mediatek/mtk-scpsys.c
+++ b/drivers/soc/mediatek/mtk-scpsys.c
@@ -411,12 +411,17 @@  static int scpsys_power_off(struct generic_pm_domain *genpd)
 	return ret;
 }
 
-static void init_clks(struct platform_device *pdev, struct clk **clk)
+static int init_clks(struct platform_device *pdev, struct clk **clk)
 {
 	int i;
 
-	for (i = CLK_NONE + 1; i < CLK_MAX; i++)
+	for (i = CLK_NONE + 1; i < CLK_MAX; i++) {
 		clk[i] = devm_clk_get(&pdev->dev, clk_names[i]);
+		if (IS_ERR(clk[i]))
+			return PTR_ERR(clk[i]);
+	}
+	
+	return 0;
 }
 
 static struct scp *init_scp(struct platform_device *pdev,
@@ -426,7 +431,7 @@  static struct scp *init_scp(struct platform_device *pdev,
 {
 	struct genpd_onecell_data *pd_data;
 	struct resource *res;
-	int i, j;
+	int i, j, ret;
 	struct scp *scp;
 	struct clk *clk[CLK_MAX];
 
@@ -481,7 +486,9 @@  static struct scp *init_scp(struct platform_device *pdev,
 
 	pd_data->num_domains = num;
 
-	init_clks(pdev, clk);
+	ret = init_clks(pdev, clk);
+	if (ret)
+		return ERR_PTR(-ENOMEM);
 
 	for (i = 0; i < num; i++) {
 		struct scp_domain *scpd = &scp->domains[i];