Add final bits of required functionality for ChannelHelper

Add support for getting the list of available channels for a band if
available.
Add support for estimating the duration of a scan.

Change-Id: I8abe6d857400775f72969abd4b15e8763ec772c5

1 files changed, 23 insertions, 0 deletions

diff --git a/service/java/com/android/server/wifi/scanner/NoBandChannelHelper.java b/service/java/com/android/server/wifi/scanner/NoBandChannelHelper.java
index 0d4296ab3..ea1f999ce 100644
--- a/service/java/com/android/server/wifi/scanner/NoBandChannelHelper.java
+++ b/service/java/com/android/server/wifi/scanner/NoBandChannelHelper.java
@@ -29,6 +29,15 @@ import java.util.Set;
  */
 public class NoBandChannelHelper extends ChannelHelper {
 
+    private static final WifiScanner.ChannelSpec[] NO_CHANNELS = new WifiScanner.ChannelSpec[0];
+
+    /**
+     * These parameters are used to estimate the scan duration.
+     * This is a guess at the number of channels the device supports for use when a ScanSettings
+     * specifies a band instead of a list of channels.
+     */
+    private static final int ALL_BAND_CHANNEL_COUNT_ESTIMATE = 36;
+
     @Override
     public boolean settingsContainChannel(WifiScanner.ScanSettings settings, int channel) {
         if (settings.band == WifiScanner.WIFI_BAND_UNSPECIFIED) {
@@ -43,6 +52,20 @@ public class NoBandChannelHelper extends ChannelHelper {
         }
     }
 
+    @Override
+    public WifiScanner.ChannelSpec[] getAvailableScanChannels(int band) {
+        return NO_CHANNELS; // not supported
+    }
+
+    @Override
+    public int estimateScanDuration(WifiScanner.ScanSettings settings) {
+        if (settings.band == WifiScanner.WIFI_BAND_UNSPECIFIED) {
+            return settings.channels.length * SCAN_PERIOD_PER_CHANNEL_MS;
+        } else {
+            return ALL_BAND_CHANNEL_COUNT_ESTIMATE * SCAN_PERIOD_PER_CHANNEL_MS;
+        }
+    }
+
     /**
      * ChannelCollection that merges channels without knowing which channels are in each band. In
      * order to do this if any band is added or the maxChannels is exceeded then all channels will