[PATCH] mtd: rawnand: atmel: Release the HSMC clock on legacy init failure

[Wentao Liang]

When atmel_hsmc_nand_controller_legacy_init() fails after acquiring the
NFC clock with of_clk_get(), the error paths return without dropping the
clock reference.  For failures after clk_prepare_enable(), the clock is
also left enabled.  The caller returns the error without running the
controller removal path, so the reference and the enable count are both
leaked.

Add error unwinding that disables the clock when it was prepared and
always puts the reference.

Fixes: f88fc122cc34 ("mtd: nand: Cleanup/rework the atmel_nand driver")
Cc: stable at vger.kernel.org
Assisted-by: DeepSeek-V4.1-Flash and OpenAI Codex
Signed-off-by: Wentao Liang <vulab at iscas.ac.cn>
---
 drivers/mtd/nand/raw/atmel/nand-controller.c | 26 ++++++++++++--------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nand/raw/atmel/nand-controller.c
index 0bdbcbb50d94..f798ac7b9c51 100644
--- a/drivers/mtd/nand/raw/atmel/nand-controller.c
+++ b/drivers/mtd/nand/raw/atmel/nand-controller.c
@@ -2185,7 +2185,7 @@ atmel_hsmc_nand_controller_legacy_init(struct atmel_hsmc_nand_controller *nc)
 	if (ret) {
 		dev_err(dev, "Failed to enable the HSMC clock (err = %d)\n",
 			ret);
-		goto out;
+		goto out_put_clk;
 	}
 
 	nc->irq = of_irq_get(nand_np, 0);
@@ -2194,20 +2194,20 @@ atmel_hsmc_nand_controller_legacy_init(struct atmel_hsmc_nand_controller *nc)
 		if (ret != -EPROBE_DEFER)
 			dev_err(dev, "Failed to get IRQ number (err = %d)\n",
 				ret);
-		goto out;
+		goto out_disable_clk;
 	}
 
 	ret = of_address_to_resource(nfc_np, 0, &res);
 	if (ret) {
 		dev_err(dev, "Invalid or missing NFC IO resource (err = %d)\n",
 			ret);
-		goto out;
+		goto out_disable_clk;
 	}
 
 	iomem = devm_ioremap_resource(dev, &res);
 	if (IS_ERR(iomem)) {
 		ret = PTR_ERR(iomem);
-		goto out;
+		goto out_disable_clk;
 	}
 
 	regmap_conf.name = "nfc-io";
@@ -2217,20 +2217,20 @@ atmel_hsmc_nand_controller_legacy_init(struct atmel_hsmc_nand_controller *nc)
 		ret = PTR_ERR(nc->io);
 		dev_err(dev, "Could not create NFC IO regmap (err = %d)\n",
 			ret);
-		goto out;
+		goto out_disable_clk;
 	}
 
 	ret = of_address_to_resource(nfc_np, 1, &res);
 	if (ret) {
 		dev_err(dev, "Invalid or missing HSMC resource (err = %d)\n",
 			ret);
-		goto out;
+		goto out_disable_clk;
 	}
 
 	iomem = devm_ioremap_resource(dev, &res);
 	if (IS_ERR(iomem)) {
 		ret = PTR_ERR(iomem);
-		goto out;
+		goto out_disable_clk;
 	}
 
 	regmap_conf.name = "smc";
@@ -2240,24 +2240,30 @@ atmel_hsmc_nand_controller_legacy_init(struct atmel_hsmc_nand_controller *nc)
 		ret = PTR_ERR(nc->base.smc);
 		dev_err(dev, "Could not create NFC IO regmap (err = %d)\n",
 			ret);
-		goto out;
+		goto out_disable_clk;
 	}
 
 	ret = of_address_to_resource(nfc_np, 2, &res);
 	if (ret) {
 		dev_err(dev, "Invalid or missing SRAM resource (err = %d)\n",
 			ret);
-		goto out;
+		goto out_disable_clk;
 	}
 
 	nc->sram.virt = devm_ioremap_resource(dev, &res);
 	if (IS_ERR(nc->sram.virt)) {
 		ret = PTR_ERR(nc->sram.virt);
-		goto out;
+		goto out_disable_clk;
 	}
 
 	nc->sram.dma = res.start;
 
+	goto out;
+
+out_disable_clk:
+	clk_disable_unprepare(nc->clk);
+out_put_clk:
+	clk_put(nc->clk);
 out:
 	of_node_put(nfc_np);
 
-- 
2.34.1