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authorIngo Molnar <mingo@elte.hu>2008-11-18 21:37:07 +0100
committerIngo Molnar <mingo@elte.hu>2008-11-18 21:37:07 +0100
commit5177dc3f2b3220b2dcfcf35eb9e6ec53ee818231 (patch)
tree29dd80a7b33426d0890aa07b5864224557c62af7 /Documentation/hwmon
parent0bb943c7a2136716757a263f604d26309fd98042 (diff)
parent7f0f598a0069d1ab072375965a4b69137233169c (diff)
Merge branch 'linus' into tracing/urgent
Diffstat (limited to 'Documentation/hwmon')
-rw-r--r--Documentation/hwmon/adt746267
-rw-r--r--Documentation/hwmon/lis3lv02d49
2 files changed, 116 insertions, 0 deletions
diff --git a/Documentation/hwmon/adt7462 b/Documentation/hwmon/adt7462
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+Kernel driver adt7462
+======================
+
+Supported chips:
+ * Analog Devices ADT7462
+ Prefix: 'adt7462'
+ Addresses scanned: I2C 0x58, 0x5C
+ Datasheet: Publicly available at the Analog Devices website
+
+Author: Darrick J. Wong
+
+Description
+-----------
+
+This driver implements support for the Analog Devices ADT7462 chip family.
+
+This chip is a bit of a beast. It has 8 counters for measuring fan speed. It
+can also measure 13 voltages or 4 temperatures, or various combinations of the
+two. See the chip documentation for more details about the exact set of
+configurations. This driver does not allow one to configure the chip; that is
+left to the system designer.
+
+A sophisticated control system for the PWM outputs is designed into the ADT7462
+that allows fan speed to be adjusted automatically based on any of the three
+temperature sensors. Each PWM output is individually adjustable and
+programmable. Once configured, the ADT7462 will adjust the PWM outputs in
+response to the measured temperatures without further host intervention. This
+feature can also be disabled for manual control of the PWM's.
+
+Each of the measured inputs (voltage, temperature, fan speed) has
+corresponding high/low limit values. The ADT7462 will signal an ALARM if
+any measured value exceeds either limit.
+
+The ADT7462 samples all inputs continuously. The driver will not read
+the registers more often than once every other second. Further,
+configuration data is only read once per minute.
+
+Special Features
+----------------
+
+The ADT7462 have a 10-bit ADC and can therefore measure temperatures
+with 0.25 degC resolution.
+
+The Analog Devices datasheet is very detailed and describes a procedure for
+determining an optimal configuration for the automatic PWM control.
+
+The driver will report sensor labels when it is able to determine that
+information from the configuration registers.
+
+Configuration Notes
+-------------------
+
+Besides standard interfaces driver adds the following:
+
+* PWM Control
+
+* pwm#_auto_point1_pwm and temp#_auto_point1_temp and
+* pwm#_auto_point2_pwm and temp#_auto_point2_temp -
+
+point1: Set the pwm speed at a lower temperature bound.
+point2: Set the pwm speed at a higher temperature bound.
+
+The ADT7462 will scale the pwm between the lower and higher pwm speed when
+the temperature is between the two temperature boundaries. PWM values range
+from 0 (off) to 255 (full speed). Fan speed will be set to maximum when the
+temperature sensor associated with the PWM control exceeds temp#_max.
+
diff --git a/Documentation/hwmon/lis3lv02d b/Documentation/hwmon/lis3lv02d
new file mode 100644
index 000000000000..65dfb0c0fd67
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+Kernel driver lis3lv02d
+==================
+
+Supported chips:
+
+ * STMicroelectronics LIS3LV02DL and LIS3LV02DQ
+
+Author:
+ Yan Burman <burman.yan@gmail.com>
+ Eric Piel <eric.piel@tremplin-utc.net>
+
+
+Description
+-----------
+
+This driver provides support for the accelerometer found in various HP laptops
+sporting the feature officially called "HP Mobile Data Protection System 3D" or
+"HP 3D DriveGuard". It detect automatically laptops with this sensor. Known models
+(for now the HP 2133, nc6420, nc2510, nc8510, nc84x0, nw9440 and nx9420) will
+have their axis automatically oriented on standard way (eg: you can directly
+play neverball). The accelerometer data is readable via
+/sys/devices/platform/lis3lv02d.
+
+Sysfs attributes under /sys/devices/platform/lis3lv02d/:
+position - 3D position that the accelerometer reports. Format: "(x,y,z)"
+calibrate - read: values (x, y, z) that are used as the base for input class device operation.
+ write: forces the base to be recalibrated with the current position.
+rate - reports the sampling rate of the accelerometer device in HZ
+
+This driver also provides an absolute input class device, allowing
+the laptop to act as a pinball machine-esque joystick.
+
+Axes orientation
+----------------
+
+For better compatibility between the various laptops. The values reported by
+the accelerometer are converted into a "standard" organisation of the axes
+(aka "can play neverball out of the box"):
+ * When the laptop is horizontal the position reported is about 0 for X and Y
+and a positive value for Z
+ * If the left side is elevated, X increases (becomes positive)
+ * If the front side (where the touchpad is) is elevated, Y decreases (becomes negative)
+ * If the laptop is put upside-down, Z becomes negative
+
+If your laptop model is not recognized (cf "dmesg"), you can send an email to the
+authors to add it to the database. When reporting a new laptop, please include
+the output of "dmidecode" plus the value of /sys/devices/platform/lis3lv02d/position
+in these four cases.
+