Add Event log for RAT switch.

Write event log while the 2G/3G radio access technology switched.

2 files changed, 17 insertions, 0 deletions

diff --git a/telephony/java/com/android/internal/telephony/TelephonyEventLog.java b/telephony/java/com/android/internal/telephony/TelephonyEventLog.java
index cdce488..0f15cb6 100644
--- a/telephony/java/com/android/internal/telephony/TelephonyEventLog.java
+++ b/telephony/java/com/android/internal/telephony/TelephonyEventLog.java
@@ -32,4 +32,5 @@ public final class TelephonyEventLog {
     public static final int EVENT_LOG_PDP_NETWORK_DROP = 50109;
     public static final int EVENT_LOG_CDMA_DATA_SETUP_FAILED = 50110;
     public static final int EVENT_LOG_CDMA_DATA_DROP = 50111;
+    public static final int EVENT_LOG_GSM_RAT_SWITCHED = 50112;
 }
diff --git a/telephony/java/com/android/internal/telephony/gsm/GsmServiceStateTracker.java b/telephony/java/com/android/internal/telephony/gsm/GsmServiceStateTracker.java
index 8140654..3bf76d4 100644
--- a/telephony/java/com/android/internal/telephony/gsm/GsmServiceStateTracker.java
+++ b/telephony/java/com/android/internal/telephony/gsm/GsmServiceStateTracker.java
@@ -38,6 +38,7 @@ import android.provider.Settings.SettingNotFoundException;
 import android.provider.Telephony.Intents;
 import android.telephony.ServiceState;
 import android.telephony.SignalStrength;
+import android.telephony.TelephonyManager;
 import android.telephony.gsm.GsmCellLocation;
 import android.text.TextUtils;
 import android.util.Config;
@@ -848,6 +849,21 @@ final class GsmServiceStateTracker extends ServiceStateTracker {
         cellLoc = newCellLoc;
         newCellLoc = tcl;
 
+
+        // Add an event log when network type switched
+        // TODO: we may add filtering to reduce the event logged,
+        // i.e. check preferred network setting, only switch to 2G, etc
+        if (hasNetworkTypeChanged) {
+            int cid = -1;
+            GsmCellLocation loc = ((GsmCellLocation)phone.getCellLocation());
+            if (loc != null) cid = loc.getCid();
+            EventLog.List val = new EventLog.List(cid, networkType, newNetworkType);
+            EventLog.writeEvent(TelephonyEventLog.EVENT_LOG_GSM_RAT_SWITCHED, val);
+            Log.d(LOG_TAG,
+                    "RAT switched " + networkTypeToString(networkType) + " -> "
+                    + networkTypeToString(newNetworkType) + " at cell " + cid);
+        }
+
         gprsState = newGPRSState;
         networkType = newNetworkType;