From: Ahmed S. Darwish <ahmed.darw...@valeo.com>

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
completly exiting the driver init code.

Signed-off-by: Ahmed S. Darwish <ahmed.darw...@valeo.com>
---
 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 640b0eb..068e76c 100644
--- a/drivers/net/can/usb/kvaser_usb.c
+++ b/drivers/net/can/usb/kvaser_usb.c
@@ -1614,7 +1614,7 @@ 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)
@@ -1632,7 +1632,15 @@ 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 completly 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);
-- 
1.9.1

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