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author | Ingo Molnar <mingo@kernel.org> | 2014-08-22 10:04:15 +0200 |
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committer | Ingo Molnar <mingo@kernel.org> | 2014-08-22 10:04:15 +0200 |
commit | 80b304fd00e8b667775ff791121b61ecd7cd0c03 (patch) | |
tree | b4f2ec59fe062c43343ee4c2f10a6bcd0e4dcd1b /Documentation/laptops/toshiba_haps.txt | |
parent | fb21b84e7f809ef04b1e5aed5d463cf0d4866638 (diff) | |
parent | 6a7519e81321343165f89abb8b616df186d3e57a (diff) | |
download | lwn-80b304fd00e8b667775ff791121b61ecd7cd0c03.tar.gz lwn-80b304fd00e8b667775ff791121b61ecd7cd0c03.zip |
Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent
Pull EFI fixes from Matt Fleming:
* WARN_ON(!spin_is_locked()) always triggers on non-SMP machines.
Swap it for the more canonical lockdep_assert_held() which always
does the right thing - Guenter Roeck
* Assign the correct value to efi.runtime_version on arm64 so that all
the runtime services can be invoked - Semen Protsenko
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'Documentation/laptops/toshiba_haps.txt')
-rw-r--r-- | Documentation/laptops/toshiba_haps.txt | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/Documentation/laptops/toshiba_haps.txt b/Documentation/laptops/toshiba_haps.txt new file mode 100644 index 000000000000..11dbcfdc9e7a --- /dev/null +++ b/Documentation/laptops/toshiba_haps.txt @@ -0,0 +1,76 @@ +Kernel driver toshiba_haps +Toshiba HDD Active Protection Sensor +==================================== + +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" officialy, +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. |