diff options
author | Linus Torvalds <torvalds@g5.osdl.org> | 2006-09-26 11:49:46 -0700 |
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committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-09-26 11:49:46 -0700 |
commit | dd77a4ee0f3981693d4229aa1d57cea9e526ff47 (patch) | |
tree | cb486be20b950201103a03636cbb1e1d180f0098 /Documentation/ABI/testing/sysfs-power | |
parent | e8216dee838c09776680a6f1a2e54d81f3cdfa14 (diff) | |
parent | 7e9f4b2d3e21e87c26025810413ef1592834e63b (diff) |
Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (47 commits)
Driver core: Don't call put methods while holding a spinlock
Driver core: Remove unneeded routines from driver core
Driver core: Fix potential deadlock in driver core
PCI: enable driver multi-threaded probe
Driver Core: add ability for drivers to do a threaded probe
sysfs: add proper sysfs_init() prototype
drivers/base: check errors
drivers/base: Platform notify needs to occur before drivers attach to the device
v4l-dev2: handle __must_check
add CONFIG_ENABLE_MUST_CHECK
add __must_check to device management code
Driver core: fixed add_bind_files() definition
Driver core: fix comments in drivers/base/power/resume.c
sysfs_remove_bin_file: no return value, dump_stack on error
kobject: must_check fixes
Driver core: add ability for devices to create and remove bin files
Class: add support for class interfaces for devices
Driver core: create devices/virtual/ tree
Driver core: add device_rename function
Driver core: add ability for classes to handle devices properly
...
Diffstat (limited to 'Documentation/ABI/testing/sysfs-power')
-rw-r--r-- | Documentation/ABI/testing/sysfs-power | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power new file mode 100644 index 000000000000..d882f8093871 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-power @@ -0,0 +1,88 @@ +What: /sys/power/ +Date: August 2006 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power directory will contain files that will + provide a unified interface to the power management + subsystem. + +What: /sys/power/state +Date: August 2006 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/state file controls the system power state. + Reading from this file returns what states are supported, + which is hard-coded to 'standby' (Power-On Suspend), 'mem' + (Suspend-to-RAM), and 'disk' (Suspend-to-Disk). + + Writing to this file one of these strings causes the system to + transition into that state. Please see the file + Documentation/power/states.txt for a description of each of + these states. + +What: /sys/power/disk +Date: August 2006 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/disk file controls the operating mode of the + suspend-to-disk mechanism. Reading from this file returns + the name of the method by which the system will be put to + sleep on the next suspend. There are four methods supported: + 'firmware' - means that the memory image will be saved to disk + by some firmware, in which case we also assume that the + firmware will handle the system suspend. + 'platform' - the memory image will be saved by the kernel and + the system will be put to sleep by the platform driver (e.g. + ACPI or other PM registers). + 'shutdown' - the memory image will be saved by the kernel and + the system will be powered off. + 'reboot' - the memory image will be saved by the kernel and + the system will be rebooted. + + The suspend-to-disk method may be chosen by writing to this + file one of the accepted strings: + + 'firmware' + 'platform' + 'shutdown' + 'reboot' + + It will only change to 'firmware' or 'platform' if the system + supports that. + +What: /sys/power/image_size +Date: August 2006 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/image_size file controls the size of the image + created by the suspend-to-disk mechanism. It can be written a + string representing a non-negative integer that will be used + as an upper limit of the image size, in bytes. The kernel's + suspend-to-disk code will do its best to ensure the image size + will not exceed this number. However, if it turns out to be + impossible, the kernel will try to suspend anyway using the + smallest image possible. In particular, if "0" is written to + this file, the suspend image will be as small as possible. + + Reading from this file will display the current image size + limit, which is set to 500 MB by default. + +What: /sys/power/pm_trace +Date: August 2006 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/pm_trace file controls the code which saves the + last PM event point in the RTC across reboots, so that you can + debug a machine that just hangs during suspend (or more + commonly, during resume). Namely, the RTC is only used to save + the last PM event point if this file contains '1'. Initially + it contains '0' which may be changed to '1' by writing a + string representing a nonzero integer into it. + + To use this debugging feature you should attempt to suspend + the machine, then reboot it and run + + dmesg -s 1000000 | grep 'hash matches' + + CAUTION: Using it will cause your machine's real-time (CMOS) + clock to be set to a random invalid time after a resume. |