[lvc-project] [PATCH net v2] net: stmmac: add clk_prepare_enable() error handling

[Pavel Zhigulin]

The driver previously ignored the return value of 'clk_prepare_enable()'
for both the CSR clock and the PCLK in 'stmmac_probe_config_dt()' function.

Add 'clk_prepare_enable()' return value checks.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: bfab27a146ed ("stmmac: add the experimental PCI support")
Signed-off-by: Pavel Zhigulin <Pavel.Zhigulin at kaspersky.com>
---
v2: Fix 'ret' value initialization after build bot notification.
v1: https://lore.kernel.org/all/20251113134009.79440-1-Pavel.Zhigulin@kaspersky.com/

 drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
index 27bcaae07a7f..8f9eb9683d2b 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
@@ -632,7 +632,9 @@ stmmac_probe_config_dt(struct platform_device *pdev, u8 *mac)
 			dev_warn(&pdev->dev, "Cannot get CSR clock\n");
 			plat->stmmac_clk = NULL;
 		}
-		clk_prepare_enable(plat->stmmac_clk);
+		rc = clk_prepare_enable(plat->stmmac_clk);
+		if (rc < 0)
+			dev_warn(&pdev->dev, "Cannot enable CSR clock: %d\n", rc);
 	}

 	plat->pclk = devm_clk_get_optional(&pdev->dev, "pclk");
@@ -640,7 +642,12 @@ stmmac_probe_config_dt(struct platform_device *pdev, u8 *mac)
 		ret = plat->pclk;
 		goto error_pclk_get;
 	}
-	clk_prepare_enable(plat->pclk);
+	rc = clk_prepare_enable(plat->pclk);
+	if (rc < 0) {
+		ret = ERR_PTR(rc);
+		dev_err(&pdev->dev, "Cannot enable pclk: %d\n", rc);
+		goto error_pclk_get;
+	}

 	/* Fall-back to main clock in case of no PTP ref is passed */
 	plat->clk_ptp_ref = devm_clk_get(&pdev->dev, "ptp_ref");
--
2.43.0