netdev - [PATCH v2] net: fec: Do proper error checking for optional clks

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220521083425.787204-1-u.kleine-koenig@pengutronix.de>
Date:   Sat, 21 May 2022 10:34:25 +0200
From:   Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>
To:     Joakim Zhang <qiangqing.zhang@....com>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>
Cc:     netdev@...r.kernel.org, NXP Linux Team <linux-imx@....com>,
        kernel@...gutronix.de, Andrew Lunn <andrew@...n.ch>
Subject: [PATCH v2] net: fec: Do proper error checking for optional clks

An error code returned by devm_clk_get() might have other meanings than
"This clock doesn't exist". So use devm_clk_get_optional() and handle
all remaining errors as fatal.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
---
Hello,

as Andrew pointed out, there are two clocks that can benefit from better
error handling during probe. So compared to (implicit) v1 this also
cares for "enet_clk_ref".

Best regards
Uwe

 drivers/net/ethernet/freescale/fec_main.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 11227f51404c..907b379d2c83 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -3866,17 +3866,21 @@ fec_probe(struct platform_device *pdev)
 	fep->itr_clk_rate = clk_get_rate(fep->clk_ahb);
 
 	/* enet_out is optional, depends on board */
-	fep->clk_enet_out = devm_clk_get(&pdev->dev, "enet_out");
-	if (IS_ERR(fep->clk_enet_out))
-		fep->clk_enet_out = NULL;
+	fep->clk_enet_out = devm_clk_get_optional(&pdev->dev, "enet_out");
+	if (IS_ERR(fep->clk_enet_out)) {
+		ret = PTR_ERR(fep->clk_enet_out);
+		goto failed_clk;
+	}
 
 	fep->ptp_clk_on = false;
 	mutex_init(&fep->ptp_clk_mutex);
 
 	/* clk_ref is optional, depends on board */
-	fep->clk_ref = devm_clk_get(&pdev->dev, "enet_clk_ref");
-	if (IS_ERR(fep->clk_ref))
-		fep->clk_ref = NULL;
+	fep->clk_ref = devm_clk_get_optional(&pdev->dev, "enet_clk_ref");
+	if (IS_ERR(fep->clk_ref)) {
+		ret = PTR_ERR(fep->clk_ref);
+		goto failed_clk;
+	}
 	fep->clk_ref_rate = clk_get_rate(fep->clk_ref);
 
 	/* clk_2x_txclk is optional, depends on board */

base-commit: 3123109284176b1532874591f7c81f3837bbdc17
-- 
2.35.1