aboutsummaryrefslogtreecommitdiff
path: root/Documentation/power/devices.txt
AgeCommit message (Collapse)Author
2008-04-19PM: Handle device registrations during suspend/resumeRafael J. Wysocki
Modify the PM core to protect its data structures, specifically the dpm_active list, from being corrupted if a child of the currently suspending device is registered concurrently with its ->suspend() callback. In that case, since the new device (the child) is added to dpm_active after its parent, the PM core will attempt to suspend it after the parent, which is wrong. Introduce a new member of struct dev_pm_info, called 'sleeping', and use it to check if the parent of the device being added to dpm_active has been suspended, in which case the device registration fails. Also, use 'sleeping' for checking if the ordering of devices on dpm_active is correct. Introduce variable 'all_sleeping' that will be set to 'true' once all devices have been suspended and make new device registrations fail until 'all_sleeping' is reset to 'false', in order to avoid having unsuspended devices around while the system is going into a sleep state. Remove pm_sleep_rwsem which is not necessary any more. Special thanks to Alan Stern for discussions and suggestions that lead to the creation of this patch. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-02-23PM: Introduce PM_EVENT_HIBERNATE callback stateRafael J. Wysocki
During the last step of hibernation in the "platform" mode (with the help of ACPI) we use the suspend code, including the devices' ->suspend() methods, to prepare the system for entering the ACPI S4 system sleep state. But at least for some devices the operations performed by the ->suspend() callback in that case must be different from its operations during regular suspend. For this reason, introduce the new PM event type PM_EVENT_HIBERNATE and pass it to the device drivers' ->suspend() methods during the last phase of hibernation, so that they can distinguish this case and handle it as appropriate. Modify the drivers that handle PM_EVENT_SUSPEND in a special way and need to handle PM_EVENT_HIBERNATE in the same way. These changes are necessary to fix a hibernation regression related to the i915 driver (ref. http://lkml.org/lkml/2008/2/22/488). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Tested-by: Jeff Chua <jeff.chua.linux@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-01PM: Remove obsolete /sys/devices/.../power/state docsDavid Brownell
The /sys/devices/.../power/state files have been gone for a while now, but I just noticed some documentation that still refers to them. (Fortunately described as DEPRECATED and WILL REMOVE). Time to remove that obsolete documentation too ... Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Len Brown <len.brown@intel.com>
2006-09-25updated Documentation/power/devices.txtDavid Brownell
This turned into a rewrite of Documentation/power/devices.txt: - Provide more of the "big picture" - Fixup some of the horribly ancient/obsolete description of device suspend() semantics; lots of text just got deleted. - Add a decent description of PM_EVENT_* codes, including the new PRETHAW code needed in some swsusp scenarios. - Describe the new PM factorization from Linus: * class suspend, current suspend, then suspend_late * NOT suspend_prepare, it wasn't really usable * resume_early, current resume, class resume. - Updates power/state docs to be correct, and deprecate its usage except for driver testing. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-21[PATCH] remove duplication from Documentation/power/devices.txtDavid Brownell
Remove a chunk of duplicated documentation text. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-05-17[PATCH] Driver Core: remove driver model detach_stateDavid Brownell
The driver model has a "detach_state" mechanism that: - Has never been used by any in-kernel drive; - Is superfluous, since driver remove() methods can do the same thing; - Became buggy when the suspend() parameter changed semantics and type; - Could self-deadlock when called from certain suspend contexts; - Is effectively wasted documentation, object code, and headspace. This removes that "detach_state" mechanism; net code shrink, as well as a per-device saving in the driver model and sysfs. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!