diff options
author | Johannes Berg <johannes@sipsolutions.net> | 2007-04-30 18:09:53 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-04-30 19:40:40 -0400 |
commit | 11d77d0c01b80e44c7aceb21928508dafce774f9 (patch) | |
tree | 4952f15df4ea2fcdba824aec5689ee9c0c7ceb90 /Documentation/power/states.txt | |
parent | fe0c935a6cbf25d72a27c7a345df8a2151de0b74 (diff) |
power management: remove firmware disk mode
This patch removes the firmware disk suspend mode which is the wrong approach,
it is supposed to be used for implementing firmware-based disk suspend but
cannot actually be used for that.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: <linux-pm@lists.linux-foundation.org>
Cc: David Brownell <david-b@pacbell.net>
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>
Cc: 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 'Documentation/power/states.txt')
-rw-r--r-- | Documentation/power/states.txt | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/Documentation/power/states.txt b/Documentation/power/states.txt index 0931a330d362..34800cc521bf 100644 --- a/Documentation/power/states.txt +++ b/Documentation/power/states.txt | |||
@@ -62,17 +62,18 @@ setup via another operating system for it to use. Despite the | |||
62 | inconvenience, this method requires minimal work by the kernel, since | 62 | inconvenience, this method requires minimal work by the kernel, since |
63 | the firmware will also handle restoring memory contents on resume. | 63 | the firmware will also handle restoring memory contents on resume. |
64 | 64 | ||
65 | If the kernel is responsible for persistently saving state, a mechanism | 65 | For suspend-to-disk, a mechanism called swsusp called 'swsusp' (Swap |
66 | called 'swsusp' (Swap Suspend) is used to write memory contents to | 66 | Suspend) is used to write memory contents to free swap space. |
67 | free swap space. swsusp has some restrictive requirements, but should | 67 | swsusp has some restrictive requirements, but should work in most |
68 | work in most cases. Some, albeit outdated, documentation can be found | 68 | cases. Some, albeit outdated, documentation can be found in |
69 | in Documentation/power/swsusp.txt. | 69 | Documentation/power/swsusp.txt. Alternatively, userspace can do most |
70 | of the actual suspend to disk work, see userland-swsusp.txt. | ||
70 | 71 | ||
71 | Once memory state is written to disk, the system may either enter a | 72 | Once memory state is written to disk, the system may either enter a |
72 | low-power state (like ACPI S4), or it may simply power down. Powering | 73 | low-power state (like ACPI S4), or it may simply power down. Powering |
73 | down offers greater savings, and allows this mechanism to work on any | 74 | down offers greater savings, and allows this mechanism to work on any |
74 | system. However, entering a real low-power state allows the user to | 75 | system. However, entering a real low-power state allows the user to |
75 | trigger wake up events (e.g. pressing a key or opening a laptop lid). | 76 | trigger wake up events (e.g. pressing a key or opening a laptop lid). |
76 | 77 | ||
77 | A transition from Suspend-to-Disk to the On state should take about 30 | 78 | A transition from Suspend-to-Disk to the On state should take about 30 |
78 | seconds, though it's typically a bit more with the current | 79 | seconds, though it's typically a bit more with the current |