can: mscan: simplify clock enable/disable

All the NULL checks are pointless, clk_*() routines already deal with
NULL just fine.

Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Link: https://lore.kernel.org/r/1594972875-27631-1-git-send-email-zhangchangzhong@huawei.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
diff --git a/drivers/net/can/mscan/mscan.c b/drivers/net/can/mscan/mscan.c
index 0b3532d..640ba1b 100644
--- a/drivers/net/can/mscan/mscan.c
+++ b/drivers/net/can/mscan/mscan.c
@@ -541,16 +541,12 @@
 	struct mscan_priv *priv = netdev_priv(dev);
 	struct mscan_regs __iomem *regs = priv->reg_base;
 
-	if (priv->clk_ipg) {
-		ret = clk_prepare_enable(priv->clk_ipg);
-		if (ret)
-			goto exit_retcode;
-	}
-	if (priv->clk_can) {
-		ret = clk_prepare_enable(priv->clk_can);
-		if (ret)
-			goto exit_dis_ipg_clock;
-	}
+	ret = clk_prepare_enable(priv->clk_ipg);
+	if (ret)
+		goto exit_retcode;
+	ret = clk_prepare_enable(priv->clk_can);
+	if (ret)
+		goto exit_dis_ipg_clock;
 
 	/* common open */
 	ret = open_candev(dev);
@@ -584,11 +580,9 @@
 	napi_disable(&priv->napi);
 	close_candev(dev);
 exit_dis_can_clock:
-	if (priv->clk_can)
-		clk_disable_unprepare(priv->clk_can);
+	clk_disable_unprepare(priv->clk_can);
 exit_dis_ipg_clock:
-	if (priv->clk_ipg)
-		clk_disable_unprepare(priv->clk_ipg);
+	clk_disable_unprepare(priv->clk_ipg);
 exit_retcode:
 	return ret;
 }
@@ -607,10 +601,8 @@
 	close_candev(dev);
 	free_irq(dev->irq, dev);
 
-	if (priv->clk_can)
-		clk_disable_unprepare(priv->clk_can);
-	if (priv->clk_ipg)
-		clk_disable_unprepare(priv->clk_ipg);
+	clk_disable_unprepare(priv->clk_can);
+	clk_disable_unprepare(priv->clk_ipg);
 
 	return 0;
 }