I am trying to collect power usage statistics for the Android G1 Phone. I am interested in knowing the values of Voltage and Current, and then able to collect statistics as reported in this PDF.
I am able to get the value of Battery voltage through registering for an intent receiver to receive the Broadcast for ACTION_BATTERY_CHANGED. But the problem is that Android does not expose the value of current through this SDK interface.
One way I tried is via sysfs interface, where I can view the battery current value from adb shell, using the following command
$cat /sys/class/power_supply/battery/batt_current
449
But that too works only if the phone is connected via USB interface. If I disconnect the phone, I see the value of batt_current as '0'. I am not sure why the value of current reported is zero. It should be more than zero, right?
Any suggestion / pointers for getting battery current value? Also please correct me if I am wrong.
You could just look at the source code for the Current Widget. It has hard coded path's to where certain platforms store the current values.
/*
* Copyright (c) 2010-2011 Ran Manor
*
* This file is part of CurrentWidget.
*
* CurrentWidget is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* CurrentWidget is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with CurrentWidget. If not, see <http://www.gnu.org/licenses/>.
*/
package com.manor.currentwidget.library;
import java.io.File;
import android.os.Build;
import android.util.Log;
public class CurrentReaderFactory {
static public Long getValue() {
File f = null;
// htc desire hd / desire z / inspire?
if (Build.MODEL.toLowerCase().contains("desire hd") ||
Build.MODEL.toLowerCase().contains("desire z") ||
Build.MODEL.toLowerCase().contains("inspire")) {
f = new File("/sys/class/power_supply/battery/batt_current");
if (f.exists()) {
return OneLineReader.getValue(f, false);
}
}
// nexus one cyangoenmod
f = new File("/sys/devices/platform/ds2784-battery/getcurrent");
if (f.exists()) {
return OneLineReader.getValue(f, true);
}
// sony ericsson xperia x1
f = new File("/sys/devices/platform/i2c-adapter/i2c-0/0-0036/power_supply/ds2746-battery/current_now");
if (f.exists()) {
return OneLineReader.getValue(f, false);
}
// xdandroid
/*if (Build.MODEL.equalsIgnoreCase("MSM")) {*/
f = new File("/sys/devices/platform/i2c-adapter/i2c-0/0-0036/power_supply/battery/current_now");
if (f.exists()) {
return OneLineReader.getValue(f, false);
}
/*}*/
// droid eris
f = new File("/sys/class/power_supply/battery/smem_text");
if (f.exists()) {
Long value = SMemTextReader.getValue();
if (value != null)
return value;
}
// htc sensation / evo 3d
f = new File("/sys/class/power_supply/battery/batt_attr_text");
if (f.exists())
{
Long value = BattAttrTextReader.getValue();
if (value != null)
return value;
}
// some htc devices
f = new File("/sys/class/power_supply/battery/batt_current");
if (f.exists())
return OneLineReader.getValue(f, false);
// nexus one
f = new File("/sys/class/power_supply/battery/current_now");
if (f.exists())
return OneLineReader.getValue(f, true);
// samsung galaxy vibrant
f = new File("/sys/class/power_supply/battery/batt_chg_current");
if (f.exists())
return OneLineReader.getValue(f, false);
// sony ericsson x10
f = new File("/sys/class/power_supply/battery/charger_current");
if (f.exists())
return OneLineReader.getValue(f, false);
// Nook Color
f = new File("/sys/class/power_supply/max17042-0/current_now");
if (f.exists())
return OneLineReader.getValue(f, false);
return null;
}
}