On 02/17/2014 10:23 AM, Kedareswara rao Appana wrote:

+/**
+ * xcan_get_berr_counter - error counter routine
+ * @ndev:	Pointer to net_device structure
+ * @bec:	Pointer to can_berr_counter structure
+ *
+ * This is the driver error counter routine.
+ * Return: 0 always
+ */
+static int xcan_get_berr_counter(const struct net_device *ndev,
+					struct can_berr_counter *bec)
+{
+	struct xcan_priv *priv = netdev_priv(ndev);
+	int ret;
+
+	ret = clk_prepare_enable(priv->devclk);
+	if (ret)
+		goto err;
+
+	ret = clk_prepare_enable(priv->aperclk);
+	if (ret)
+		goto err_clk;
+
+	bec->txerr = priv->read_reg(priv, XCAN_ECR_OFFSET) & XCAN_ECR_TEC_MASK;
+	bec->rxerr = ((priv->read_reg(priv, XCAN_ECR_OFFSET) &
+			XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT);

You have to disable the clock when leaving this function. Otherwise the
clocks will be unbalanced.

+	return 0;
+
+err_clk:
+	clk_disable_unprepare(priv->devclk);
+err:
+	return ret;
+}

Marc

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