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    SubjectRe: [linux-usb-devel] Re: Commit "[PATCH] USB: Always do usb-handoff" breaks my powerbook

    > Why should x86-specific-BIOS-USB-handoff-specific-crap-PCI-quirks be
    > even _compiled_ on PowerPC systems that have nothing remotely like
    > the affected hardware (BIOS & PS/2 serio chip)?

    For starters, none of the controller specs say that the handshaking
    is x86-specific. There's a certain amount of "x86 Linux gets the
    most testing" going on here. Plus a lot of "nobody really used that
    usb-handoff code before, except to fix semi-broken x86 systems".

    One requirement coming from x86/DOS legacy support though is that the
    system probably expects to "work like DOS" at various boot stages.
    Hence the way some systems take kbd/mouse input from USB and jam it
    through PS2 serio hardware, so DOS will see it. Which is why x86
    hardware generally _does_ need to use these handhaking mechanisms,
    to kick the BIOS off the hardware. (And why the USB folk have been
    very used to telling folk to disable BIOS support for USB. That's
    fine advice unless you've got a USB keyboard or mouse.)

    > The difference is, OpenFirmware is nice and clean and stops messing  
    > with hardware before handing off to the new kernel.

    That's a nice design policy (IMO) but sometimes folk also like to
    draw the firmware/OS boundary in different ways.

    In any case ... let's all just blame this on DOS, and move on to
    something that's not as twentieth-century. :)

    - Dave

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