Add support for supplicant SCAN_INTERVAL

Also, allow scan interval for framework and supplicant
to be configured at build time or run time

Bug: 4144882
Change-Id: I877f4bcc872597b44d3f4da85cf2bc0f16e09444
diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 6deb5a0..c75b0fe 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -3303,12 +3303,20 @@
         public static final String WIFI_IDLE_MS = "wifi_idle_ms";
 
         /**
-         * The interval in milliseconds to issue scans when the driver is
-         * started. This is necessary to allow wifi to connect to an
-         * access point when the driver is suspended.
+         * The interval in milliseconds to issue wake up scans when wifi needs
+         * to connect. This is necessary to connect to an access point when
+         * device is on the move and the screen is off.
          * @hide
          */
-        public static final String WIFI_SCAN_INTERVAL_MS = "wifi_scan_interval_ms";
+        public static final String WIFI_FRAMEWORK_SCAN_INTERVAL_MS =
+                "wifi_framework_scan_interval_ms";
+
+        /**
+         * The interval in milliseconds to scan as used by the wifi supplicant
+         * @hide
+         */
+        public static final String WIFI_SUPPLICANT_SCAN_INTERVAL_MS =
+                "wifi_supplicant_scan_interval_ms";
 
         /**
          * The interval in milliseconds at which to check packet counts on the
diff --git a/core/jni/android_net_wifi_Wifi.cpp b/core/jni/android_net_wifi_Wifi.cpp
index 667ba75..494dc27 100644
--- a/core/jni/android_net_wifi_Wifi.cpp
+++ b/core/jni/android_net_wifi_Wifi.cpp
@@ -556,7 +556,7 @@
     return doBooleanCommand(cmdstr, "OK");
 }
 
-static void android_net_wifi_enableBackgroundScan(JNIEnv* env, jobject clazz, jboolean enable)
+static void android_net_wifi_enableBackgroundScanCommand(JNIEnv* env, jobject clazz, jboolean enable)
 {
     //Note: BGSCAN-START and BGSCAN-STOP are documented in core/res/res/values/config.xml
     //and will need an update if the names are changed
@@ -568,6 +568,16 @@
     }
 }
 
+static void android_net_wifi_setScanIntervalCommand(JNIEnv* env, jobject clazz, jint scanInterval)
+{
+    char cmdstr[BUF_SIZE];
+
+    int numWritten = snprintf(cmdstr, sizeof(cmdstr), "SCAN_INTERVAL %d", scanInterval);
+
+    if(numWritten < (int)sizeof(cmdstr)) doBooleanCommand(cmdstr, "OK");
+}
+
+
 // ----------------------------------------------------------------------------
 
 /*
@@ -635,7 +645,8 @@
         (void*) android_net_wifi_setSuspendOptimizationsCommand},
     { "setCountryCodeCommand", "(Ljava/lang/String;)Z",
         (void*) android_net_wifi_setCountryCodeCommand},
-    { "enableBackgroundScan", "(Z)V", (void*) android_net_wifi_enableBackgroundScan},
+    { "enableBackgroundScanCommand", "(Z)V", (void*) android_net_wifi_enableBackgroundScanCommand},
+    { "setScanIntervalCommand", "(I)V", (void*) android_net_wifi_setScanIntervalCommand},
 };
 
 int register_android_net_wifi_WifiManager(JNIEnv* env)
diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index 56bc1d3..107a06a 100755
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -209,6 +209,15 @@
          The driver commands needed to support the feature are BGSCAN-START and BGSCAN-STOP -->
     <bool translatable="false" name="config_wifi_background_scan_support">false</bool>
 
+    <!-- Integer indicating wpa_supplicant scan interval in milliseconds -->
+    <integer translatable="false" name="config_wifi_supplicant_scan_interval">15000</integer>
+
+    <!-- Integer indicating the framework scan interval in milliseconds. This is used in the scenario
+         where the chipset does not support background scanning (config_wifi_background_scan_suport
+         is false) to set up a periodic wake up scan so that the device can connect to a new access
+         point on the move. A value of 0 means no periodic scans will be used in the framework. -->
+    <integer translatable="false" name="config_wifi_framework_scan_interval">300000</integer>
+
     <!-- Flag indicating whether the keyguard should be bypassed when
          the slider is open.  This can be set or unset depending how easily
          the slider can be opened (for example, in a pocket or purse). -->