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    SubjectRe: [PATCH v4 4/4] can: kvaser_usb: Retry first bulk transfer on -ETIMEDOUT
    On 01/11/2015 09:45 PM, Ahmed S. Darwish wrote:
    > From: Ahmed S. Darwish <ahmed.darwish@valeo.com>
    >
    > (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 <ahmed.darwish@valeo.com>

    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.

    Marc
    --
    Pengutronix e.K. | Marc Kleine-Budde |
    Industrial Linux Solutions | Phone: +49-231-2826-924 |
    Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
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