[3.11.y.z extended stable] Patch "can: flexcan: Check the return value from clk_prepare_enable()" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    can: flexcan: Check the return value from clk_prepare_enable()

to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From f956eb25b3162abfe1f97dd7c029a649927505a2 Mon Sep 17 00:00:00 2001
From: Fabio Estevam <fabio.estevam at freescale.com>
Date: Mon, 22 Jul 2013 12:41:40 -0300
Subject: can: flexcan: Check the return value from clk_prepare_enable()

commit aa10181bdac99a623517f0f2bfa14cd98c749246 upstream.

clk_prepare_enable() may fail, so let's check its return value and propagate it
in the case of error.

Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
Signed-off-by: Marc Kleine-Budde <mkl at pengutronix.de>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/net/can/flexcan.c | 28 ++++++++++++++++++++--------
 1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 394b2eb..0bd9e2f 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -846,12 +846,17 @@ static int flexcan_open(struct net_device *dev)
 	struct flexcan_priv *priv = netdev_priv(dev);
 	int err;

-	clk_prepare_enable(priv->clk_ipg);
-	clk_prepare_enable(priv->clk_per);
+	err = clk_prepare_enable(priv->clk_ipg);
+	if (err)
+		return err;
+
+	err = clk_prepare_enable(priv->clk_per);
+	if (err)
+		goto out_disable_ipg;

 	err = open_candev(dev);
 	if (err)
-		goto out;
+		goto out_disable_per;

 	err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
 	if (err)
@@ -873,8 +878,9 @@ static int flexcan_open(struct net_device *dev)
 	free_irq(dev->irq, dev);
  out_close:
 	close_candev(dev);
- out:
+ out_disable_per:
 	clk_disable_unprepare(priv->clk_per);
+ out_disable_ipg:
 	clk_disable_unprepare(priv->clk_ipg);

 	return err;
@@ -931,8 +937,13 @@ static int register_flexcandev(struct net_device *dev)
 	struct flexcan_regs __iomem *regs = priv->base;
 	u32 reg, err;

-	clk_prepare_enable(priv->clk_ipg);
-	clk_prepare_enable(priv->clk_per);
+	err = clk_prepare_enable(priv->clk_ipg);
+	if (err)
+		return err;
+
+	err = clk_prepare_enable(priv->clk_per);
+	if (err)
+		goto out_disable_ipg;

 	/* select "bus clock", chip must be disabled */
 	flexcan_chip_disable(priv);
@@ -957,15 +968,16 @@ static int register_flexcandev(struct net_device *dev)
 	if (!(reg & FLEXCAN_MCR_FEN)) {
 		netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
 		err = -ENODEV;
-		goto out;
+		goto out_disable_per;
 	}

 	err = register_candev(dev);

- out:
+ out_disable_per:
 	/* disable core and turn off clocks */
 	flexcan_chip_disable(priv);
 	clk_disable_unprepare(priv->clk_per);
+ out_disable_ipg:
 	clk_disable_unprepare(priv->clk_ipg);

 	return err;
--
1.9.0