[PATCH 4.14 165/191] can: flexcan: flexcan_chip_stop(): add error handling and propagate error value

Greg Kroah-Hartman
2020-10-27T18:09:27Z

From: Joakim Zhang <qiangqing.zhang@nxp.com>

[ 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@nxp.com>
[mkl: introduce flexcan_chip_stop_disable_on_error() and use it in flexcan_close()]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20200922144429.2613631-11-mkl@pengutronix.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/can/flexcan.c | 34 ++++++++++++++++++++++++++++------
1 file changed, 28 insertions(+), 6 deletions(-)

diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 84dd79041285a..94468a883f369 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -1055,18 +1055,23 @@ 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 */
flexcan_write(0, &regs->imask2);
@@ -1076,6 +1081,23 @@ 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)
@@ -1129,7 +1151,7 @@ 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);

free_irq(dev->irq, dev);
clk_disable_unprepare(priv->clk_per);
--
2.25.1