mirror of https://gitee.com/openkylin/linux.git
88 lines
3.0 KiB
ReStructuredText
88 lines
3.0 KiB
ReStructuredText
====================================
|
|
Toshiba HDD Active Protection Sensor
|
|
====================================
|
|
|
|
Kernel driver: toshiba_haps
|
|
|
|
Author: Azael Avalos <coproscefalo@gmail.com>
|
|
|
|
|
|
.. 0. Contents
|
|
|
|
1. Description
|
|
2. Interface
|
|
3. Accelerometer axes
|
|
4. Supported devices
|
|
5. Usage
|
|
|
|
|
|
1. Description
|
|
--------------
|
|
|
|
This driver provides support for the accelerometer found in various Toshiba
|
|
laptops, being called "Toshiba HDD Protection - Shock Sensor" officially,
|
|
and detects laptops automatically with this device.
|
|
On Windows, Toshiba provided software monitors this device and provides
|
|
automatic HDD protection (head unload) on sudden moves or harsh vibrations,
|
|
however, this driver only provides a notification via a sysfs file to let
|
|
userspace tools or daemons act accordingly, as well as providing a sysfs
|
|
file to set the desired protection level or sensor sensibility.
|
|
|
|
|
|
2. Interface
|
|
------------
|
|
|
|
This device comes with 3 methods:
|
|
|
|
==== =====================================================================
|
|
_STA Checks existence of the device, returning Zero if the device does not
|
|
exists or is not supported.
|
|
PTLV Sets the desired protection level.
|
|
RSSS Shuts down the HDD protection interface for a few seconds,
|
|
then restores normal operation.
|
|
==== =====================================================================
|
|
|
|
Note:
|
|
The presence of Solid State Drives (SSD) can make this driver to fail loading,
|
|
given the fact that such drives have no movable parts, and thus, not requiring
|
|
any "protection" as well as failing during the evaluation of the _STA method
|
|
found under this device.
|
|
|
|
|
|
3. Accelerometer axes
|
|
---------------------
|
|
|
|
This device does not report any axes, however, to query the sensor position
|
|
a couple HCI (Hardware Configuration Interface) calls (0x6D and 0xA6) are
|
|
provided to query such information, handled by the kernel module toshiba_acpi
|
|
since kernel version 3.15.
|
|
|
|
|
|
4. Supported devices
|
|
--------------------
|
|
|
|
This driver binds itself to the ACPI device TOS620A, and any Toshiba laptop
|
|
with this device is supported, given the fact that they have the presence of
|
|
conventional HDD and not only SSD, or a combination of both HDD and SSD.
|
|
|
|
|
|
5. Usage
|
|
--------
|
|
|
|
The sysfs files under /sys/devices/LNXSYSTM:00/LNXSYBUS:00/TOS620A:00/ are:
|
|
|
|
================ ============================================================
|
|
protection_level The protection_level is readable and writeable, and
|
|
provides a way to let userspace query the current protection
|
|
level, as well as set the desired protection level, the
|
|
available protection levels are::
|
|
|
|
============ ======= ========== ========
|
|
0 - Disabled 1 - Low 2 - Medium 3 - High
|
|
============ ======= ========== ========
|
|
|
|
reset_protection The reset_protection entry is writeable only, being "1"
|
|
the only parameter it accepts, it is used to trigger
|
|
a reset of the protection interface.
|
|
================ ============================================================
|