[PATCH 5.4 05/90] net: macb: Fix runtime PM refcounting

From: Greg Kroah-Hartman
Date: Wed May 13 2020 - 05:49:23 EST


From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

[ Upstream commit 0ce205d4660c312cdeb4a81066616dcc6f3799c4 ]

The commit e6a41c23df0d, while trying to fix an issue,

("net: macb: ensure interface is not suspended on at91rm9200")

introduced a refcounting regression, because in error case refcounter
must be balanced. Fix it by calling pm_runtime_put_noidle() in error case.

While here, fix the same mistake in other couple of places.

Fixes: e6a41c23df0d ("net: macb: ensure interface is not suspended on at91rm9200")
Cc: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
Cc: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/cadence/macb_main.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 234c13ebbc41b..dd2a605c5c2ed 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -334,8 +334,10 @@ static int macb_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
int status;

status = pm_runtime_get_sync(&bp->pdev->dev);
- if (status < 0)
+ if (status < 0) {
+ pm_runtime_put_noidle(&bp->pdev->dev);
goto mdio_pm_exit;
+ }

status = macb_mdio_wait_for_idle(bp);
if (status < 0)
@@ -367,8 +369,10 @@ static int macb_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
int status;

status = pm_runtime_get_sync(&bp->pdev->dev);
- if (status < 0)
+ if (status < 0) {
+ pm_runtime_put_noidle(&bp->pdev->dev);
goto mdio_pm_exit;
+ }

status = macb_mdio_wait_for_idle(bp);
if (status < 0)
@@ -3691,8 +3695,10 @@ static int at91ether_open(struct net_device *dev)
int ret;

ret = pm_runtime_get_sync(&lp->pdev->dev);
- if (ret < 0)
+ if (ret < 0) {
+ pm_runtime_put_noidle(&lp->pdev->dev);
return ret;
+ }

/* Clear internal statistics */
ctl = macb_readl(lp, NCR);
--
2.20.1