Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/kernel/Documentation/hwmon/adt7470 b/kernel/Documentation/hwmon/adt7470
new file mode 100644
index 000000000..8ce4aa0a0
--- /dev/null
+++ b/kernel/Documentation/hwmon/adt7470
@@ -0,0 +1,73 @@
+Kernel driver adt7470
+=====================
+
+Supported chips:
+  * Analog Devices ADT7470
+    Prefix: 'adt7470'
+    Addresses scanned: I2C 0x2C, 0x2E, 0x2F
+    Datasheet: Publicly available at the Analog Devices website
+
+Author: Darrick J. Wong
+
+Description
+-----------
+
+This driver implements support for the Analog Devices ADT7470 chip.  There may
+be other chips that implement this interface.
+
+The ADT7470 uses the 2-wire interface compatible with the SMBus 2.0
+specification. Using an analog to digital converter it measures up to ten (10)
+external temperatures. It has four (4) 16-bit counters for measuring fan speed.
+There are four (4) PWM outputs that can be used to control fan speed.
+
+A sophisticated control system for the PWM outputs is designed into the ADT7470
+that allows fan speed to be adjusted automatically based on any of the ten
+temperature sensors. Each PWM output is individually adjustable and
+programmable. Once configured, the ADT7470 will adjust the PWM outputs in
+response to the measured temperatures with further host intervention.  This
+feature can also be disabled for manual control of the PWM's.
+
+Each of the measured inputs (temperature, fan speed) has corresponding high/low
+limit values. The ADT7470 will signal an ALARM if any measured value exceeds
+either limit.
+
+The ADT7470 samples all inputs continuously.  A kernel thread is started up for
+the purpose of periodically querying the temperature sensors, thus allowing the
+automatic fan pwm control to set the fan speed.  The driver will not read the
+registers more often than once every 5 seconds.  Further, configuration data is
+only read once per minute.
+
+Special Features
+----------------
+
+The ADT7470 has a 8-bit ADC and is capable of measuring temperatures with 1
+degC resolution.
+
+The Analog Devices datasheet is very detailed and describes a procedure for
+determining an optimal configuration for the automatic PWM control.
+
+Configuration Notes
+-------------------
+
+Besides standard interfaces driver adds the following:
+
+* PWM Control
+
+* pwm#_auto_point1_pwm and pwm#_auto_point1_temp and
+* pwm#_auto_point2_pwm and pwm#_auto_point2_temp -
+
+point1: Set the pwm speed at a lower temperature bound.
+point2: Set the pwm speed at a higher temperature bound.
+
+The ADT7470 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
+pwm#_auto_point2_temp.
+
+Notes
+-----
+
+The temperature inputs no longer need to be read periodically from userspace in
+order for the automatic pwm algorithm to run.  This was the case for earlier
+versions of the driver.