[Telemetry] Support dumpsys power monitoring on the Nexus 5.

build/android/pylib/android_commands.py

 # 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.
 
 """Provides an interface to communicate with the device via the adb command.
 
 Assumes adb binary is currently on system path.
 """
 # pylint: disable-all
 
@@ skipping 60 matching lines @@
 PIE_WRAPPER_PATH = constants.TEST_EXECUTABLE_DIR + '/run_pie'
 
 CONTROL_USB_CHARGING_COMMANDS = [
   {
     # Nexus 4
     'witness_file': '/sys/module/pm8921_charger/parameters/disabled',
     'enable_command': 'echo 0 > /sys/module/pm8921_charger/parameters/disabled',
     'disable_command':
         'echo 1 > /sys/module/pm8921_charger/parameters/disabled',
   },
+  {
+    # Nexus 5
+    # Setting the HIZ bit of the bq24192 causes the charger to actually ignore

[pasko, 2014/10/14 09:16:22]

Wow! Cool! How do I discover similar things for newer devices? TI datasheets are
complex :(

+    # energy coming from USB. Setting the power_supply offline just updates the
+    # Android system to reflect that.
+    'witness_file': '/sys/kernel/debug/bq24192/INPUT_SRC_CONT',
+    'enable_command': (
+        'echo 0x4A > /sys/kernel/debug/bq24192/INPUT_SRC_CONT && '
+        'echo 1 > /sys/class/power_supply/usb/online'),
+    'disable_command': (
+        'echo 0xCA > /sys/kernel/debug/bq24192/INPUT_SRC_CONT && '
+        'chmod 644 /sys/class/power_supply/usb/online && '
+        'echo 0 > /sys/class/power_supply/usb/online'),
+  },
 ]
 
 class DeviceTempFile(object):
   def __init__(self, android_commands, prefix='temp_file', suffix=''):
     """Find an unused temporary file path in the devices external directory.
 
     When this object is closed, the file will be deleted on the device.
     """
     self.android_commands = android_commands
     while True:
@@ skipping 1860 matching lines @@
   """
   def __init__(self, output):
     self._output = output
 
   def write(self, data):
     data = data.replace('\r\r\n', '\n')
     self._output.write(data)
 
   def flush(self):
     self._output.flush()