From 14c10c2a1dd8eb8e00b750b521753260befa2789 Mon Sep 17 00:00:00 2001
From: "Ahmed S. Darwish" <ahmed.darwish@valeo.com>
Date: Mon, 26 Jan 2015 07:24:06 +0200
Subject: [PATCH] can: kvaser_usb: Retry the first bulk transfer on -ETIMEDOUT
On some x86 laptops, plugging a Kvaser device again after an
unplug makes the firmware always ignore the very first command.
For such a case, provide some room for retries instead of
completely exiting the driver init code.
Signed-off-by: Ahmed S. Darwish <ahmed.darwish@valeo.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
drivers/net/can/usb/kvaser_usb.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c
index f0c62075df0a..55407b9663a6 100644
--- a/drivers/net/can/usb/kvaser_usb.c
+++ b/drivers/net/can/usb/kvaser_usb.c
@@ -1585,7 +1585,7 @@ static int kvaser_usb_probe(struct usb_interface *intf,
{
struct kvaser_usb *dev;
int err = -ENOMEM;
- int i;
+ int i, retry = 3;
dev = devm_kzalloc(&intf->dev, sizeof(*dev), GFP_KERNEL);
if (!dev)
@@ -1603,7 +1603,15 @@ static int kvaser_usb_probe(struct usb_interface *intf,
usb_set_intfdata(intf, dev);
- err = kvaser_usb_get_software_info(dev);
+ /* On some x86 laptops, plugging a Kvaser device again after
+ * an unplug makes the firmware always ignore the very first
+ * command. For such a case, provide some room for retries
+ * instead of completely exiting the driver.
+ */
+ do {
+ err = kvaser_usb_get_software_info(dev);
+ } while (--retry && err == -ETIMEDOUT);
+
if (err) {
dev_err(&intf->dev,
"Cannot get software infos, error %d\n", err);
--
2.34.1