| 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: can: kvaser_usb: Retry the first bulk transfer on -ETIMEDOUT |
| |
| From: "Ahmed S. Darwish" <ahmed.darwish@valeo.com> |
| |
| commit 14c10c2a1dd8eb8e00b750b521753260befa2789 upstream. |
| |
| 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> |
| Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/net/can/usb/kvaser_usb.c | 12 ++++++++++-- |
| 1 file changed, 10 insertions(+), 2 deletions(-) |
| |
| --- a/drivers/net/can/usb/kvaser_usb.c |
| +++ b/drivers/net/can/usb/kvaser_usb.c |
| @@ -1588,7 +1588,7 @@ static int kvaser_usb_probe(struct usb_i |
| { |
| struct kvaser_usb *dev; |
| int err = -ENOMEM; |
| - int i; |
| + int i, retry = 3; |
| |
| dev = devm_kzalloc(&intf->dev, sizeof(*dev), GFP_KERNEL); |
| if (!dev) |
| @@ -1606,7 +1606,15 @@ static int kvaser_usb_probe(struct usb_i |
| |
| 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); |