inconvenience, this method requires minimal work by the kernel, since
the firmware will also handle restoring memory contents on resume.
-If the kernel is responsible for persistently saving state, a mechanism
-called 'swsusp' (Swap Suspend) is used to write memory contents to
-free swap space. swsusp has some restrictive requirements, but should
-work in most cases. Some, albeit outdated, documentation can be found
-in Documentation/power/swsusp.txt.
+For suspend-to-disk, a mechanism called 'swsusp' (Swap Suspend) is used
+to write memory contents to free swap space. swsusp has some restrictive
+requirements, but should work in most cases. Some, albeit outdated,
+documentation can be found in Documentation/power/swsusp.txt.
+Alternatively, userspace can do most of the actual suspend to disk work,
+see userland-swsusp.txt.
Once memory state is written to disk, the system may either enter a
low-power state (like ACPI S4), or it may simply power down. Powering
down offers greater savings, and allows this mechanism to work on any
system. However, entering a real low-power state allows the user to
-trigger wake up events (e.g. pressing a key or opening a laptop lid).
+trigger wake up events (e.g. pressing a key or opening a laptop lid).
A transition from Suspend-to-Disk to the On state should take about 30
seconds, though it's typically a bit more with the current
git.openpandora.org / pandora-kernel.git / blobdiff