Patch "can: flexcan: flexcan_chip_stop(): add error handling and propagate error value" has been added to the 5.8-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    can: flexcan: flexcan_chip_stop(): add error handling and propagate error value

to the 5.8-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     can-flexcan-flexcan_chip_stop-add-error-handling-and.patch
and it can be found in the queue-5.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 0aa445740d4d642b8952dd8f1d0b68efe1457235
Author: Joakim Zhang <qiangqing.zhang@xxxxxxx>
Date:   Tue Sep 22 16:44:19 2020 +0200

    can: flexcan: flexcan_chip_stop(): add error handling and propagate error value
    
    [ Upstream commit 9ad02c7f4f279504bdd38ab706fdc97d5f2b2a9c ]
    
    This patch implements error handling and propagates the error value of
    flexcan_chip_stop(). This function will be called from flexcan_suspend()
    in an upcoming patch in some SoCs which support LPSR mode.
    
    Add a new function flexcan_chip_stop_disable_on_error() that tries to
    disable the chip even in case of errors.
    
    Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
    [mkl: introduce flexcan_chip_stop_disable_on_error() and use it in flexcan_close()]
    Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20200922144429.2613631-11-mkl@xxxxxxxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 94d10ec954a05..2ac7a667bde35 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -1260,18 +1260,23 @@ static int flexcan_chip_start(struct net_device *dev)
 	return err;
 }
 
-/* flexcan_chip_stop
+/* __flexcan_chip_stop
  *
- * this functions is entered with clocks enabled
+ * this function is entered with clocks enabled
  */
-static void flexcan_chip_stop(struct net_device *dev)
+static int __flexcan_chip_stop(struct net_device *dev, bool disable_on_error)
 {
 	struct flexcan_priv *priv = netdev_priv(dev);
 	struct flexcan_regs __iomem *regs = priv->regs;
+	int err;
 
 	/* freeze + disable module */
-	flexcan_chip_freeze(priv);
-	flexcan_chip_disable(priv);
+	err = flexcan_chip_freeze(priv);
+	if (err && !disable_on_error)
+		return err;
+	err = flexcan_chip_disable(priv);
+	if (err && !disable_on_error)
+		goto out_chip_unfreeze;
 
 	/* Disable all interrupts */
 	priv->write(0, &regs->imask2);
@@ -1281,6 +1286,23 @@ static void flexcan_chip_stop(struct net_device *dev)
 
 	flexcan_transceiver_disable(priv);
 	priv->can.state = CAN_STATE_STOPPED;
+
+	return 0;
+
+ out_chip_unfreeze:
+	flexcan_chip_unfreeze(priv);
+
+	return err;
+}
+
+static inline int flexcan_chip_stop_disable_on_error(struct net_device *dev)
+{
+	return __flexcan_chip_stop(dev, true);
+}
+
+static inline int flexcan_chip_stop(struct net_device *dev)
+{
+	return __flexcan_chip_stop(dev, false);
 }
 
 static int flexcan_open(struct net_device *dev)
@@ -1362,7 +1384,7 @@ static int flexcan_close(struct net_device *dev)
 
 	netif_stop_queue(dev);
 	can_rx_offload_disable(&priv->offload);
-	flexcan_chip_stop(dev);
+	flexcan_chip_stop_disable_on_error(dev);
 
 	can_rx_offload_del(&priv->offload);
 	free_irq(dev->irq, dev);