mtd: nand: ecc-mtk: handle ECC clock enable failures

mtk_ecc_get() gets a reference to the ECC platform device, obtains the
provider state and then enables the ECC clock before initializing the
hardware.

The clk_prepare_enable() return value is currently ignored.  If enabling
the clock fails, the code still touches the ECC registers and returns a
live ECC handle to the caller.  The provider device reference acquired
by of_find_device_by_node() is also kept even though the handle setup
failed.

Propagate the clock enable error and drop the provider device reference
on that failure path.

Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

diff --git a/drivers/mtd/nand/ecc-mtk.c b/drivers/mtd/nand/ecc-mtk.c
index c75bb8b80cc1e14b6de7ed7c6935490518930f63..39be2e3e4ee485768ae05f6f1d47ff3d25d810d7 100644 (file)
--- a/drivers/mtd/nand/ecc-mtk.c
+++ b/drivers/mtd/nand/ecc-mtk.c
@@ -265,6 +265,7 @@ static struct mtk_ecc *mtk_ecc_get(struct device_node *np)
 {
        struct platform_device *pdev;
        struct mtk_ecc *ecc;
+       int ret;
 
        pdev = of_find_device_by_node(np);
        if (!pdev)
@@ -276,7 +277,12 @@ static struct mtk_ecc *mtk_ecc_get(struct device_node *np)
                return ERR_PTR(-EPROBE_DEFER);
        }
 
-       clk_prepare_enable(ecc->clk);
+       ret = clk_prepare_enable(ecc->clk);
+       if (ret) {
+               put_device(&pdev->dev);
+               return ERR_PTR(ret);
+       }
+
        mtk_ecc_hw_init(ecc);
 
        return ecc;