From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     matthias.bgg@gmail.com, lgirdwood@gmail.com, broonie@kernel.org
Cc:     linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org,
        Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: [PATCH v4] isoc: mediatek: potential use of error pointer
Date:   Fri, 17 Dec 2021 22:35:51 +0800
Message-Id: <20211217143551.675368-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

The return value of devm_clk_get() needs to be checked.
To avoid use of error pointer in case of the failure of alloc.

Fixes: 6078c651947a ("soc: mediatek: Refine scpsys to support multiple platform")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
Changelog:

v3 -> v4

*Change 1. Change the "-ENOMEM" to "ERR_PTR(-ENOMEM)".
*Change 2. Add the IS_ERR to check the error code from devm_clk_get().
*Change 3. Change back the "ERR_PTR(-ENOMEM)" to "-ENOMEM".
---
 drivers/soc/mediatek/mtk-scpsys.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c
index ca75b14931ec..778d6ffc42b8 100644
--- a/drivers/soc/mediatek/mtk-scpsys.c
+++ b/drivers/soc/mediatek/mtk-scpsys.c
@@ -411,12 +411,16 @@ 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 -ENOMEM;
+	}
+	return 0;
 }
 
 static struct scp *init_scp(struct platform_device *pdev,
@@ -426,7 +430,7 @@ 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 +485,9 @@ 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];
-- 
2.25.1