From 455561fb618fde40558776b5b8435f9420f335db Mon Sep 17 00:00:00 2001
From: Anssi Hannula <anssi.hannula@bitwise.fi>
Date: Mon, 10 Oct 2022 17:08:28 +0200
Subject: [PATCH] can: kvaser_usb_leaf: Fix TX queue out of sync after restart
Git-commit: 455561fb618fde40558776b5b8435f9420f335db
Patch-mainline: v6.1-rc1
References: git-fixes
The TX queue seems to be implicitly flushed by the hardware during
bus-off or bus-off recovery, but the driver does not reset the TX
bookkeeping.
Despite not resetting TX bookkeeping the driver still re-enables TX
queue unconditionally, leading to "cannot find free context" /
NETDEV_TX_BUSY errors if the TX queue was full at bus-off time.
Fix that by resetting TX bookkeeping on CAN restart.
Tested with 0bfd:0124 Kvaser Mini PCI Express 2xHS FW 4.18.778.
Cc: stable@vger.kernel.org
Fixes: 080f40a6fa28 ("can: kvaser_usb: Add support for Kvaser CAN/USB devices")
Tested-by: Jimmy Assarsson <extja@kvaser.com>
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Link: https://lore.kernel.org/all/20221010150829.199676-4-extja@kvaser.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/can/usb/kvaser_usb/kvaser_usb.h | 2 ++
drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c | 2 +-
drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c | 2 ++
3 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb.h b/drivers/net/can/usb/kvaser_usb/kvaser_usb.h
index 841da29cef93..f6c0938027ec 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb.h
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb.h
@@ -178,6 +178,8 @@ struct kvaser_usb_dev_cfg {
extern const struct kvaser_usb_dev_ops kvaser_usb_hydra_dev_ops;
extern const struct kvaser_usb_dev_ops kvaser_usb_leaf_dev_ops;
+void kvaser_usb_unlink_tx_urbs(struct kvaser_usb_net_priv *priv);
+
int kvaser_usb_recv_cmd(const struct kvaser_usb *dev, void *cmd, int len,
int *actual_len);
diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
index c2bce6773adc..e91648ed7386 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
@@ -477,7 +477,7 @@ static void kvaser_usb_reset_tx_urb_contexts(struct kvaser_usb_net_priv *priv)
/* This method might sleep. Do not call it in the atomic context
* of URB completions.
*/
-static void kvaser_usb_unlink_tx_urbs(struct kvaser_usb_net_priv *priv)
+void kvaser_usb_unlink_tx_urbs(struct kvaser_usb_net_priv *priv)
{
usb_kill_anchored_urbs(&priv->tx_submitted);
kvaser_usb_reset_tx_urb_contexts(priv);
diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
index 8e11cda85624..59c220ef3049 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
@@ -1426,6 +1426,8 @@ static int kvaser_usb_leaf_set_mode(struct net_device *netdev,
switch (mode) {
case CAN_MODE_START:
+ kvaser_usb_unlink_tx_urbs(priv);
+
err = kvaser_usb_leaf_simple_cmd_async(priv, CMD_START_CHIP);
if (err)
return err;
--
2.35.3