On 01/12/2015 11:14 AM, Ahmed S. Darwish wrote: > On Sun, Jan 11, 2015 at 09:51:10PM +0100, Marc Kleine-Budde wrote: >> On 01/11/2015 09:45 PM, Ahmed S. Darwish wrote: >>> From: Ahmed S. Darwish >>> >>> (This is a draft patch, I'm not sure if this fixes the USB >>> bug or only its psymptom. Feedback from the linux-usb folks >>> is really appreciated.) >>> >>> When plugging the Kvaser USB/CAN dongle the first time, everything >>> works as expected and all of the transfers from and to the USB >>> device succeeds. >>> >>> Meanwhile, after unplugging the device and plugging it again, the >>> first bulk transfer _always_ returns an -ETIMEDOUT. The following >>> behaviour was observied: >>> >>> - Setting higher timeout values for the first bulk transfer never >>> solved the issue. >>> >>> - Unloading, then loading, our kvaser_usb module in question >>> __always__ solved the issue. >>> >>> - Checking first bulk transfer status, and retry the transfer >>> again in case of an -ETIMEDOUT also __always__ solved the issue. >>> This is what the patch below does. >>> >>> - In the testing done so far, this issue appears only on laptops >>> but never on PCs (possibly power related?) >>> >>> Signed-off-by: Ahmed S. Darwish >> >> Does this patch apply apply between 3 and 4? If not, please re-arrange >> the series. As this is a bug fix, patches 1, 2 and 4 will go via >> net/master, 3 will go via net-next/master. > > Since no one complained earlier, I guess this issue only affects > USBCAN devices. That's why I've based it above patch #3: adding > USBCAN hardware support. > > Nonetheless, it won't do any harm for the current Leaf-only > driver. So _if_ this is the correct fix, I will update the commit > log, refactor the check into a 'do { } while()' loop, and then > base it above the Leaf-only net/master fixes on patch #1, and #2. > > Any feedback on the USB side of things? Maybe you have to change the subject of this patch to be more visible on the USB list and/or add the right USB people on Cc. Marc -- Pengutronix e.K. | Marc Kleine-Budde | Industrial Linux Solutions | Phone: +49-231-2826-924 | Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |