[PATCH 5.10 07/21] net: stmmac: fix missing unlock on error in stmmac_suspend()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Yang Yingliang <yangyingliang@huawei.com>

commit 30f347ae7cc1178c431f968a89d4b4a375bc0d39 upstream

Add the missing unlock before return from stmmac_suspend()
in the error handling case.

Fixes: 5ec55823438e ("net: stmmac: add clocks management for gmac driver")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Meng Li <Meng.Li@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -5275,8 +5275,10 @@ int stmmac_suspend(struct device *dev)
 		/* Disable clock in case of PWM is off */
 		clk_disable_unprepare(priv->plat->clk_ptp_ref);
 		ret = pm_runtime_force_suspend(dev);
-		if (ret)
+		if (ret) {
+			mutex_unlock(&priv->lock);
 			return ret;
+		}
 	}
 	mutex_unlock(&priv->lock);