Initial commit of open source Workload Automation.

wlauto/utils/hwmon.py

@@ -0,0 +1,77 @@
+#    Copyright 2013-2015 ARM Limited
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+
+from wlauto.exceptions import DeviceError
+
+
+HWMON_ROOT = '/sys/class/hwmon'
+
+
+class HwmonSensor(object):
+
+    def __init__(self, device, kind, label, filepath):
+        self.device = device
+        self.kind = kind
+        self.label = label
+        self.filepath = filepath
+        self.readings = []
+
+    def take_reading(self):
+        reading = self.device.get_sysfile_value(self.filepath, int)
+        self.readings.append(reading)
+
+    def clear_readings(self):
+        self.readings = []
+
+
+def discover_sensors(device, sensor_kinds):
+    """
+    Discovers HWMON sensors available on the device.
+
+        :device: Device on which to discover HWMON sensors. Must be an instance
+                 of  :class:`AndroidDevice`.
+        :sensor_kinds: A list of names of sensor types to be discovered. The names
+                       must be as they appear prefixed to ``*_input`` files in
+                       sysfs. E.g. ``'energy'``.
+
+        :returns: A list of :class:`HwmonSensor` instantces for each found sensor. If
+                  no sensors of the specified types were discovered, an empty list
+                  will be returned.
+
+    """
+    hwmon_devices = device.listdir(HWMON_ROOT)
+    path = device.path
+    sensors = []
+    for hwmon_device in hwmon_devices:
+        try:
+            device_path = path.join(HWMON_ROOT, hwmon_device, 'device')
+            name = device.get_sysfile_value(path.join(device_path, 'name'))
+        except DeviceError:  # probably a virtual device
+            device_path = path.join(HWMON_ROOT, hwmon_device)
+            name = device.get_sysfile_value(path.join(device_path, 'name'))
+
+        for sensor_kind in sensor_kinds:
+            i = 1
+            input_path = path.join(device_path, '{}{}_input'.format(sensor_kind, i))
+            while device.file_exists(input_path):
+                label_path = path.join(device_path, '{}{}_label'.format(sensor_kind, i))
+                if device.file_exists(label_path):
+                    name += ' ' + device.get_sysfile_value(label_path)
+                sensors.append(HwmonSensor(device, sensor_kind, name, input_path))
+                i += 1
+                input_path = path.join(device_path, '{}{}_input'.format(sensor_kind, i))
+    return sensors
+