From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Kleine-Budde Subject: [PATCH 3/4] can: kvaser_usb: Retry the first bulk transfer on -ETIMEDOUT Date: Tue, 27 Jan 2015 09:01:26 +0100 Message-ID: <1422345687-12839-4-git-send-email-mkl@pengutronix.de> References: <1422345687-12839-1-git-send-email-mkl@pengutronix.de> Cc: davem@davemloft.net, linux-can@vger.kernel.org, kernel@pengutronix.de, "Ahmed S. Darwish" , linux-stable , Marc Kleine-Budde To: netdev@vger.kernel.org Return-path: In-Reply-To: <1422345687-12839-1-git-send-email-mkl@pengutronix.de> Sender: linux-can-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: "Ahmed S. Darwish" 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 Cc: linux-stable Signed-off-by: Marc Kleine-Budde --- 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); -- 2.1.4