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    SubjectRe: USB devices fail unnecessarily on unpowered hubs
    Hi!

    > Starting with 2.6.16, some USB devices fail unnecessarily on unpowered
    > hubs. Alan Stern explains,
    >
    > "The idea is that the kernel now keeps track of USB power budgets. When a
    > bus-powered device requires more current than its upstream hub is capable
    > of providing, the kernel will not configure it.
    >
    > Computers' USB ports are capable of providing a full 500 mA, so devices
    > plugged directly into the computer will work okay. However unpowered hubs
    > can provide only 100 mA to each port. Some devices require (or claim they
    > require) more current than that. As a result, they don't get configured
    > when plugged into an unpowered hub."

    Actually I have exactly opposite problem: my computer (spitz) can't
    supply full 500mA on its root hub, and linux tries to power up
    'hungry' devices, anyway, leading to very weird behaviour.

    --
    Thanks for all the (sleeping) penguins.
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