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1====================================2Toshiba HDD Active Protection Sensor3====================================4 5Kernel driver: toshiba_haps6 7Author: Azael Avalos <coproscefalo@gmail.com>8 9 10.. 0. Contents11 12 1. Description13 2. Interface14 3. Accelerometer axes15 4. Supported devices16 5. Usage17 18 191. Description20--------------21 22This driver provides support for the accelerometer found in various Toshiba23laptops, being called "Toshiba HDD Protection - Shock Sensor" officially,24and detects laptops automatically with this device.25On Windows, Toshiba provided software monitors this device and provides26automatic HDD protection (head unload) on sudden moves or harsh vibrations,27however, this driver only provides a notification via a sysfs file to let28userspace tools or daemons act accordingly, as well as providing a sysfs29file to set the desired protection level or sensor sensibility.30 31 322. Interface33------------34 35This device comes with 3 methods:36 37==== =====================================================================38_STA Checks existence of the device, returning Zero if the device does not39 exists or is not supported.40PTLV Sets the desired protection level.41RSSS Shuts down the HDD protection interface for a few seconds,42 then restores normal operation.43==== =====================================================================44 45Note:46 The presence of Solid State Drives (SSD) can make this driver to fail loading,47 given the fact that such drives have no movable parts, and thus, not requiring48 any "protection" as well as failing during the evaluation of the _STA method49 found under this device.50 51 523. Accelerometer axes53---------------------54 55This device does not report any axes, however, to query the sensor position56a couple HCI (Hardware Configuration Interface) calls (0x6D and 0xA6) are57provided to query such information, handled by the kernel module toshiba_acpi58since kernel version 3.15.59 60 614. Supported devices62--------------------63 64This driver binds itself to the ACPI device TOS620A, and any Toshiba laptop65with this device is supported, given the fact that they have the presence of66conventional HDD and not only SSD, or a combination of both HDD and SSD.67 68 695. Usage70--------71 72The sysfs files under /sys/devices/LNXSYSTM:00/LNXSYBUS:00/TOS620A:00/ are:73 74================ ============================================================75protection_level The protection_level is readable and writeable, and76 provides a way to let userspace query the current protection77 level, as well as set the desired protection level, the78 available protection levels are::79 80 ============ ======= ========== ========81 0 - Disabled 1 - Low 2 - Medium 3 - High82 ============ ======= ========== ========83 84reset_protection The reset_protection entry is writeable only, being "1"85 the only parameter it accepts, it is used to trigger86 a reset of the protection interface.87================ ============================================================88