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    SubjectRe: [PATCH] PCMCIA: prevent auto insert during resume.
    On Fri 2007-10-26 19:18:57, Rodolfo Giometti wrote:
    > On Fri, Oct 26, 2007 at 06:00:31PM +0100, Russell King wrote:
    >
    > > > > > Also if you didn't eject the socket, at resume the device will be
    > > > > > powered up again, my patch just prevents that a pre-powered off device
    > > > > > to be turned on at resume time.
    > > > > >
    > > > > > However you should consider that some embedded systems have fixed
    > > > > > PCMCIA devices that can't be removed so there are no reasons to detect
    > > > > > them after resume, nobody can change them. :)
    > > > > >
    > > > > > Also battery powered devices can go very frequently to sleep and the
    > > > > > current behavior force the user to switch off the unused device each
    > > > > > time the system resumes from sleep.
    > > > >
    > > > > I realise that. I do work on embedded devices, and this behaviour is
    > > > > explicitly there to support embedded devices.
    > > > >
    > > > > I've suggested a workable solution to you which allows both of us to
    > > > > have the behaviour we both desire from the system. That sounds like
    > > > > a negotiated solution to me...
    > > >
    > > > Do you mean to switch off the socket from userland? It could be a
    > > > solution but in this case the device is powered on each time even if
    > > > for a short delay...
    > >
    > > If it's a permanent device, and you've powered it down via pccardctl,
    > > then you've powered it down from userland. So record that it's been
    > > powered down from userland. Then, on resume, if it's been powered down
    > > from userland, don't try to re-power it on resume.
    >
    > But the userland doesn't re-power it on resume... it's the kernel
    > itself whos re-powers the device on resume. So the userland can only
    > power down the device again.

    I think Russell means: at a flag into kernel. If user powers down the
    device, set the flag. If flag is set during resume, avoid powering up
    the device.

    --
    (english) http://www.livejournal.com/~pavelmachek
    (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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