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Diffstat (limited to 'kernel/Documentation/ABI/testing/sysfs-devices-online')
| -rw-r--r-- | kernel/Documentation/ABI/testing/sysfs-devices-online | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/kernel/Documentation/ABI/testing/sysfs-devices-online b/kernel/Documentation/ABI/testing/sysfs-devices-online new file mode 100644 index 000000000..f990026c0 --- /dev/null +++ b/kernel/Documentation/ABI/testing/sysfs-devices-online @@ -0,0 +1,20 @@ +What: /sys/devices/.../online +Date: April 2013 +Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> +Description: + The /sys/devices/.../online attribute is only present for + devices whose bus types provide .online() and .offline() + callbacks. The number read from it (0 or 1) reflects the value + of the device's 'offline' field. If that number is 1 and '0' + (or 'n', or 'N') is written to this file, the device bus type's + .offline() callback is executed for the device and (if + successful) its 'offline' field is updated accordingly. In + turn, if that number is 0 and '1' (or 'y', or 'Y') is written to + this file, the device bus type's .online() callback is executed + for the device and (if successful) its 'offline' field is + updated as appropriate. + + After a successful execution of the bus type's .offline() + callback the device cannot be used for any purpose until either + it is removed (i.e. device_del() is called for it), or its bus + type's .online() is exeucted successfully. |