Re: klists and struct device semaphores

From: Dmitry Torokhov (dmitry.torokhov_at_gmail.com)
Date: 03/31/05

  • Next message: Patrick Mochel: "Re: klists and struct device semaphores"
    Date:	Thu, 31 Mar 2005 14:08:36 -0500
    To: Patrick Mochel <mochel@digitalimplant.org>
    
    

    On Thu, 31 Mar 2005 10:26:36 -0800 (PST), Patrick Mochel
    <mochel@digitalimplant.org> wrote:
    > I don't understand what you mean. Even if a device is suspended, be it
    > automatically after some amount of inactivity or as directed explicitly by
    > a user, we want to be able to open the device and have it work.
    >
    > Conversely, we only want to automatically suspend the device, or allow the
    > device to be explicitly put to sleep, if the device is not being used.

    Well, the disagreement in definition of "being used". Quite often you
    have a device "open" for extended period of time (inactive ext2
    partition is mounted on a disk) but device is not really active. You
    could power it down and only wake up when there is a read or write
    request.

    It looks like "open" and "close" are terms better suited for class
    devices while power management is applied to the "real" devices.

    -- 
    Dmitry
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  • Next message: Patrick Mochel: "Re: klists and struct device semaphores"

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