Add a class for management of thermal throttling

build/android/pylib/thermal_throttle.py

Index: build/android/pylib/thermal_throttle.py
diff --git a/build/android/pylib/thermal_throttle.py b/build/android/pylib/thermal_throttle.py
new file mode 100644
index 0000000000000000000000000000000000000000..385a48e7ef5f6a4c63e570e729e0247b5b83451b
--- /dev/null
+++ b/build/android/pylib/thermal_throttle.py
@@ -0,0 +1,47 @@
+# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import logging
+
+class ThermalThrottle(object):
+  """Class to detect and track thermal throttling
+
+  Usage:
+    Wait for IsThrottled() to be False before running test
+    After running test call HasBeenThrottled() to find out if the
+    test run was affected by thermal throttling.
+
+    Currently assumes an OMap device.
+  """
+  def __init__(self, adb):
+    self._adb = adb
+    self._throttled = False
+
+
+  def HasBeenThrottled(self):
+    """ True if there has been any throttling since the last call to
+        HasBeenThrottled or IsThrottled
+    """
+    return self._ReadLog()
+
+  def IsThrottled(self):
+    """True if currently throttled"""
+    self._ReadLog()
+    return self._throttled
+
+  def _ReadLog(self):
+    has_been_throttled = False
+    log = self._adb.RunShellCommand('dmesg -c')
+    for line in log:
+      if 'omap_thermal_throttle' in line:
+        if not self._throttled:
+          logging.warning('>>> Thermally Throttled')
+        self._throttled = True
+        has_been_throttled = True
+      if 'omap_thermal_unthrottle' in line:
+        if self._throttled:
+          logging.warning('>>> Thermally Unthrottled')
+        self._throttled = False
+        has_been_throttled = True
+    return has_been_throttled