linux-toradex.git/include/linux/notifier.h, branch v2.6.25.17

Hibernation: Add PM_RESTORE_PREPARE and PM_POST_RESTORE notifiers (rev. 2)

2008-02-01T23:30:53+00:00

Add PM_RESTORE_PREPARE and PM_POST_RESTORE notifiers to the PM core, to be used
in analogy with the existing PM_HIBERNATION_PREPARE and PM_POST_HIBERNATION
notifiers.

Signed-off-by: Alan Stern 
Acked-by: Pavel Machek 
Signed-off-by: "Rafael J. Wysocki" 
Signed-off-by: Len Brown

cpu-hotplug: replace per-subsystem mutexes with get_online_cpus()

2008-01-25T20:08:02+00:00

This patch converts the known per-subsystem mutexes to get_online_cpus
put_online_cpus. It also eliminates the CPU_LOCK_ACQUIRE and
CPU_LOCK_RELEASE hotplug notification events.

Signed-off-by: Gautham  R Shenoy 
Signed-off-by: Ingo Molnar

Console events and accessibility

2007-10-19T18:53:34+00:00

Some external modules like Speakup need to monitor console output.

This adds a VT notifier that such modules can use to get console output events:
allocation, deallocation, writes, other updates (cursor position, switch, etc.)

[akpm@linux-foundation.org: fix headers_check]
Signed-off-by: Samuel Thibault 
Cc: Dmitry Torokhov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Add kernel/notifier.c

2007-10-19T18:53:34+00:00

There is separate notifier header, but no separate notifier .c file.

Extract notifier code out of kernel/sys.c which will remain for
misc syscalls I hope. Merge kernel/die_notifier.c into kernel/notifier.c.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Alexey Dobriyan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Console keyboard events and accessibility

2007-10-19T18:53:33+00:00

Some blind people use a kernel engine called Speakup which uses hardware
synthesis to speak what gets displayed on the screen.  They use the
PC keyboard to control this engine (start/stop, accelerate, ...) and
also need to get keyboard feedback (to make sure to know what they are
typing, the caps lock status, etc.)

Up to now, the way it was done was very ugly.  Below is a patch to add a
notifier list for permitting a far better implementation, see ChangeLog
above for details.

You may wonder why this can't be done at the input layer.  The problem
is that what people want to monitor is the console keyboard, i.e. all
input keyboards that got attached to the console, and with the currently
active keymap (i.e. keysyms, not only keycodes).

This adds a keyboard notifier that such modules can use to get the keyboard
events and possibly eat them, at several stages:

- keycodes: even before translation into keysym.
- unbound keycodes: when no keysym is bound.
- unicode: when the keycode would get translated into a unicode character.
- keysym: when the keycode would get translated into a keysym.
- post_keysym: after the keysym got interpreted, so as to see the result
  (caps lock, etc.)

This also provides access to k_handler so as to permit simulation of
keypresses.

[akpm@linux-foundation.org: various fixes]
Signed-off-by: Samuel Thibault 
Cc: Jiri Kosina 
Cc: Dmitry Torokhov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[NET]: Allow netdev REGISTER/CHANGENAME events to fail

2007-07-31T09:28:15+00:00

This patch adds code to allow errors to be passed up from event
handlers of NETDEV_REGISTER and NETDEV_CHANGENAME.  It also adds
the notifier_from_errno/notifier_to_errnor helpers to pass the
errno value up to the notifier caller.

If an error is detected when a device is registered, it causes
that operation to fail.  A NETDEV_UNREGISTER will be sent to
all event handlers.

Similarly if NETDEV_CHANGENAME fails the original name is restored
and a new NETDEV_CHANGENAME event is sent.

As such all event handlers must be idempotent with respect to
these events.

When an event handler is registered NETDEV_REGISTER events are
sent for all devices currently registered.  Should any of them
fail, we will send NETDEV_GOING_DOWN/NETDEV_DOWN/NETDEV_UNREGISTER
events to that handler for the devices which have already been
registered with it.  The handler registration itself will fail.

Signed-off-by: Herbert Xu 
Signed-off-by: David S. Miller

PM: introduce hibernation and suspend notifiers

2007-07-19T17:04:42+00:00

Make it possible to register hibernation and suspend notifiers, so that
subsystems can perform hibernation-related or suspend-related operations that
should not be carried out by device drivers' .suspend() and .resume()
routines.

[akpm@linux-foundation.org: build fixes]
[akpm@linux-foundation.org: cleanups]
Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Cc: Nigel Cunningham 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

HOTPLUG: Add CPU_DYING notifier

2007-07-16T09:05:49+00:00

KVM wants a notification when a cpu is about to die, so it can disable
hardware extensions, but at a time when user processes cannot be scheduled
on the cpu, so it doesn't try to use virtualization extensions after they
have been disabled.

This adds a CPU_DYING notification.  The notification is called in atomic
context on the doomed cpu.

Signed-off-by: Avi Kivity

Add suspend-related notifications for CPU hotplug

2007-05-09T19:30:56+00:00

Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress.  This
patch introduces such notifications and causes them to be used during
suspend and resume transitions.  It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).

[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki 
Cc: Gautham R Shenoy 
Cc: Pavel Machek 
Signed-off-by: Oleg Nesterov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Define and use new events,CPU_LOCK_ACQUIRE and CPU_LOCK_RELEASE

2007-05-09T19:30:51+00:00

This is an attempt to provide an alternate mechanism for postponing
a hotplug event instead of using a global mechanism like lock_cpu_hotplug.

The proposal is to add two new events namely CPU_LOCK_ACQUIRE and
CPU_LOCK_RELEASE. The notification for these two events would be sent
out before and after a cpu_hotplug event respectively.

During the CPU_LOCK_ACQUIRE event, a cpu-hotplug-aware subsystem is
supposed to acquire any per-subsystem hotcpu mutex ( Eg. workqueue_mutex
in kernel/workqueue.c ).

During the CPU_LOCK_RELEASE release event the cpu-hotplug-aware subsystem
is supposed to release the per-subsystem hotcpu mutex.

The reasons for defining new events as opposed to reusing the existing events
like CPU_UP_PREPARE/CPU_UP_FAILED/CPU_ONLINE for locking/unlocking of
per-subsystem hotcpu mutexes are as follow:

	- CPU_LOCK_ACQUIRE: All hotcpu mutexes are taken before subsystems
	start handling pre-hotplug events like CPU_UP_PREPARE/CPU_DOWN_PREPARE
	etc, thus ensuring a clean handling of these events.

	- CPU_LOCK_RELEASE: The hotcpu mutexes will be released only after
	all subsystems have handled post-hotplug events like CPU_DOWN_FAILED,
	CPU_DEAD,CPU_ONLINE etc thereby ensuring that there are no subsequent
	clashes amongst the interdependent subsystems after a cpu hotplugs.

This patch also uses __raw_notifier_call chain in _cpu_up to take care
of the dependency between the two consequetive calls to
raw_notifier_call_chain.

[akpm@linux-foundation.org: fix a bug]
Signed-off-by: Gautham R Shenoy 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds