diff options
author | Johannes Berg <johannes@sipsolutions.net> | 2007-04-30 22:09:51 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-04-30 23:40:40 (GMT) |
commit | fe0c935a6cbf25d72a27c7a345df8a2151de0b74 (patch) | |
tree | 841a847412694ee586b0ca7e1e2ce7c45700d9b1 /arch/arm/mach-at91 | |
parent | 1173a729fc3ce2fa0d698bd39be8ff7bf6c70bf1 (diff) | |
download | linux-fsl-qoriq-fe0c935a6cbf25d72a27c7a345df8a2151de0b74.tar.xz |
rework pm_ops pm_disk_mode, kill misuse
This patch series cleans up some misconceptions about pm_ops. Some users of
the pm_ops structure attempt to use it to stop the user from entering suspend
to disk, this, however, is not possible since the user can always use
"shutdown" in /sys/power/disk and then the pm_ops are never invoked. Also,
platforms that don't support suspend to disk simply should not allow
configuring SOFTWARE_SUSPEND (read the help text on it, it only selects
suspend to disk and nothing else, all the other stuff depends on PM).
The pm_ops structure is actually intended to provide a way to enter
platform-defined sleep states (currently supported states are "standby" and
"mem" (suspend to ram)) and additionally (if SOFTWARE_SUSPEND is configured)
allows a platform to support a platform specific way to enter low-power mode
once everything has been saved to disk. This is currently only used by ACPI
(S4).
This patch:
The pm_ops.pm_disk_mode is used in totally bogus ways since nobody really
seems to understand what it actually does.
This patch clarifies the pm_disk_mode description.
It also removes all the arm and sh users that think they can veto suspend to
disk via pm_ops; not so since the user can always do echo shutdown >
/sys/power/disk, they need to find a better way involving Kconfig or such.
ACPI is the only user left with a non-zero pm_disk_mode.
The patch also sets the default mode to shutdown again, but when a new pm_ops
is registered its pm_disk_mode is selected as default, that way the default
stays for ACPI where it is apparently required.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: David Brownell <david-b@pacbell.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: <linux-pm@lists.linux-foundation.org>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/arm/mach-at91')
-rw-r--r-- | arch/arm/mach-at91/pm.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c index b49bfda..ff8db29 100644 --- a/arch/arm/mach-at91/pm.c +++ b/arch/arm/mach-at91/pm.c @@ -201,7 +201,6 @@ error: static struct pm_ops at91_pm_ops ={ - .pm_disk_mode = 0, .valid = at91_pm_valid_state, .prepare = at91_pm_prepare, .enter = at91_pm_enter, |