summaryrefslogtreecommitdiff
path: root/Documentation/admin-guide/laptops/toshiba_haps.rst
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2019-07-16 12:21:41 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-07-16 12:21:41 -0700
commitc309b6f24222246c18a8b65d3950e6e755440865 (patch)
tree11893170f5c246bb0dee8066e85878af04162ab0 /Documentation/admin-guide/laptops/toshiba_haps.rst
parent3e859477a1db52a0435d06a55fdb54f62d69c292 (diff)
parent168869492e7009b6861b615f1d030c99bc805e83 (diff)
Merge tag 'docs/v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull rst conversion of docs from Mauro Carvalho Chehab: "As agreed with Jon, I'm sending this big series directly to you, c/c him, as this series required a special care, in order to avoid conflicts with other trees" * tag 'docs/v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (77 commits) docs: kbuild: fix build with pdf and fix some minor issues docs: block: fix pdf output docs: arm: fix a breakage with pdf output docs: don't use nested tables docs: gpio: add sysfs interface to the admin-guide docs: locking: add it to the main index docs: add some directories to the main documentation index docs: add SPDX tags to new index files docs: add a memory-devices subdir to driver-api docs: phy: place documentation under driver-api docs: serial: move it to the driver-api docs: driver-api: add remaining converted dirs to it docs: driver-api: add xilinx driver API documentation docs: driver-api: add a series of orphaned documents docs: admin-guide: add a series of orphaned documents docs: cgroup-v1: add it to the admin-guide book docs: aoe: add it to the driver-api book docs: add some documentation dirs to the driver-api book docs: driver-model: move it to the driver-api book docs: lp855x-driver.rst: add it to the driver-api book ...
Diffstat (limited to 'Documentation/admin-guide/laptops/toshiba_haps.rst')
-rw-r--r--Documentation/admin-guide/laptops/toshiba_haps.rst87
1 files changed, 87 insertions, 0 deletions
diff --git a/Documentation/admin-guide/laptops/toshiba_haps.rst b/Documentation/admin-guide/laptops/toshiba_haps.rst
new file mode 100644
index 000000000000..d28b6c3f2849
--- /dev/null
+++ b/Documentation/admin-guide/laptops/toshiba_haps.rst
@@ -0,0 +1,87 @@
+====================================
+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.
+================ ============================================================