[PATCH v3 3/4] can: flexcan: switch on clocks before accessing ecr register

From: Stefan Agner
Date: Tue Jul 15 2014 - 08:56:38 EST


Reported-by: Ashutosh Singh <ashuleapyear@xxxxxxxxx>
Suggested-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
[stefan@xxxxxxxx: added return check for clk_enable_prepare]

Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
---
drivers/net/can/flexcan.c | 18 ++++++++++++++++--
1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index f425ec2..89745aa 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -383,12 +383,26 @@ static int flexcan_get_berr_counter(const struct net_device *dev,
{
const struct flexcan_priv *priv = netdev_priv(dev);
struct flexcan_regs __iomem *regs = priv->base;
- u32 reg = flexcan_read(&regs->ecr);
+ u32 reg, err;
+
+ err = clk_prepare_enable(priv->clk_ipg);
+ if (err)
+ return err;
+
+ err = clk_prepare_enable(priv->clk_per);
+ if (err)
+ goto out_disable_ipg;
+
+ reg = flexcan_read(&regs->ecr);

bec->txerr = (reg >> 0) & 0xff;
bec->rxerr = (reg >> 8) & 0xff;

- return 0;
+ clk_disable_unprepare(priv->clk_per);
+ out_disable_ipg:
+ clk_disable_unprepare(priv->clk_ipg);
+
+ return err;
}

static int flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
--
2.0.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/