wifi: Reduce the frequency of scans when in disconnected state and display ON

When STA is not connected, display is ON and there are no saved profiles then
reduce frequent scans due to scan alarm source by increasing scan alarm time
mCurrentScanAlarmMs to 5 minutes since there is already a periodic scan every
mSupplicantScanIntervalMs (15 seconds). If there are saved profiles then keep
mCurrentScanAlarmMs to 10 seconds.

Change-Id: Icc1ec5803b2048f2d12b47092894127be6626dcd
CRs-Fixed: 764660

1 files changed, 26 insertions, 4 deletions

diff --git a/service/java/com/android/server/wifi/WifiStateMachine.java b/service/java/com/android/server/wifi/WifiStateMachine.java
index a963d5e13..216474943 100755..100644
--- a/service/java/com/android/server/wifi/WifiStateMachine.java
+++ b/service/java/com/android/server/wifi/WifiStateMachine.java
@@ -3029,7 +3029,19 @@ public class WifiStateMachine extends StateMachine {
                 // Scan after 200ms
                 setScanAlarm(true, 200);
             } else if (getCurrentState() == mDisconnectedState) {
-                mCurrentScanAlarmMs = mDisconnectedScanPeriodMs;
+
+                // Configure the scan alarm time to mFrameworkScanIntervalMs
+                // (5 minutes) if there are no saved profiles as there is
+                // already a periodic scan getting issued for every
+                // mSupplicantScanIntervalMs seconds. However keep the
+                // scan frequency by setting it to mDisconnectedScanPeriodMs
+                // (10 seconds) when there are configured profiles.
+                if (mWifiConfigStore.getConfiguredNetworks().size() != 0) {
+                    mCurrentScanAlarmMs = mDisconnectedScanPeriodMs;
+                } else {
+                    mCurrentScanAlarmMs = mFrameworkScanIntervalMs;
+                }
+
                 // Scan after 200ms
                 setScanAlarm(true, 200);
             }
@@ -7693,9 +7705,19 @@ public class WifiStateMachine extends StateMachine {
                     Settings.Global.WIFI_FRAMEWORK_SCAN_INTERVAL_MS,
                     mDefaultFrameworkScanIntervalMs);
 
-            if (mScreenOn)
-                mCurrentScanAlarmMs = mDisconnectedScanPeriodMs;
-
+            // Configure the scan alarm time to mFrameworkScanIntervalMs
+            // (5 minutes) if there are no saved profiles as there is
+            // already a periodic scan getting issued for every
+            // mSupplicantScanIntervalMs seconds. However keep the
+            // scan frequency by setting it to mDisconnectedScanPeriodMs
+            // (10 seconds) when there are configured profiles.
+            if (mScreenOn) {
+                if (mWifiConfigStore.getConfiguredNetworks().size() != 0) {
+                    mCurrentScanAlarmMs = mDisconnectedScanPeriodMs;
+                } else {
+                    mCurrentScanAlarmMs = mFrameworkScanIntervalMs;
+                }
+            }
             if (PDBG) {
                 loge(" Enter disconnected State scan interval " + mFrameworkScanIntervalMs
                         + " mEnableBackgroundScan= " + mEnableBackgroundScan