From b4fc49983bd00c2609437943f6ca3483ef529665 Mon Sep 17 00:00:00 2001
From: Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>
Date: Thu, 27 Jan 2022 21:17:14 +0900
Subject: [PATCH 33/34] net: stmmac: dwmac-visconti: No change to
 ETHER_CLOCK_SEL for unexpected speed request.
Git-commit: 928d6fe996f69330ded6b887baf4534c5fac7988
References: git-fixes
Patch-mainline: v5.17-rc3

Variable clk_sel_val is not initialized in the default case of the first switch statement.
In that case, the function should return immediately without any changes to the hardware.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: b38dd98ff8d0 ("net: stmmac: Add Toshiba Visconti SoCs glue driver")
Signed-off-by: Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>
Reviewed-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac-visconti.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-visconti.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-visconti.c
index 4578c64953ea..c27441c08dd6 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-visconti.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-visconti.c
@@ -49,13 +49,15 @@ struct visconti_eth {
 	void __iomem *reg;
 	u32 phy_intf_sel;
 	struct clk *phy_ref_clk;
+	struct device *dev;
 	spinlock_t lock; /* lock to protect register update */
 };
 
 static void visconti_eth_fix_mac_speed(void *priv, unsigned int speed)
 {
 	struct visconti_eth *dwmac = priv;
-	unsigned int val, clk_sel_val;
+	struct net_device *netdev = dev_get_drvdata(dwmac->dev);
+	unsigned int val, clk_sel_val = 0;
 	unsigned long flags;
 
 	spin_lock_irqsave(&dwmac->lock, flags);
@@ -85,7 +87,9 @@ static void visconti_eth_fix_mac_speed(void *priv, unsigned int speed)
 		break;
 	default:
 		/* No bit control */
-		break;
+		netdev_err(netdev, "Unsupported speed request (%d)", speed);
+		spin_unlock_irqrestore(&dwmac->lock, flags);
+		return;
 	}
 
 	writel(val, dwmac->reg + MAC_CTRL_REG);
@@ -230,6 +234,7 @@ static int visconti_eth_dwmac_probe(struct platform_device *pdev)
 
 	spin_lock_init(&dwmac->lock);
 	dwmac->reg = stmmac_res.addr;
+	dwmac->dev = &pdev->dev;
 	plat_dat->bsp_priv = dwmac;
 	plat_dat->fix_mac_speed = visconti_eth_fix_mac_speed;
 
-- 
2.16.4