From ea8bd1d1676dd96f8f9726bb8f67fa18dec7b9c1 Mon Sep 17 00:00:00 2001
From: Mikael Kanstrup <mikael.kanstrup@sonyericsson.com>
Date: Wed, 7 Apr 2010 16:45:58 +0200
Subject: [PATCH] WLAN: Reset power save mode to startup value after DHCP
 response.

When the driver was configured to run with power save mode disabled the
power save mode incorrectly got reverted back to AUTO mode right after
DHCP response. The power save mode value is now saved so that the device
properly reverts back to a previous mode after DHCP response.

Change-Id: I5035aad10146812ecef1be8ea4b22a03e230ccc9
---
 core/jni/android_net_wifi_Wifi.cpp               | 15 +++++++++++++++
 wifi/java/android/net/wifi/WifiNative.java       |  2 ++
 wifi/java/android/net/wifi/WifiStateTracker.java | 16 ++++++++++++++--
 3 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/core/jni/android_net_wifi_Wifi.cpp b/core/jni/android_net_wifi_Wifi.cpp
index 38f3fdae2b716..f5d9eb0bf91f4 100644
--- a/core/jni/android_net_wifi_Wifi.cpp
+++ b/core/jni/android_net_wifi_Wifi.cpp
@@ -390,6 +390,20 @@ static jboolean android_net_wifi_setPowerModeCommand(JNIEnv* env, jobject clazz,
     return (jboolean)!cmdTooLong && doBooleanCommand(cmdstr, "OK");
 }
 
+static jint android_net_wifi_getPowerModeCommand(JNIEnv* env, jobject clazz)
+{
+    char reply[256];
+    int power;
+
+    if (doCommand("DRIVER GETPOWER", reply, sizeof(reply)) != 0) {
+        return (jint)-1;
+    }
+    // reply comes back in the form "powermode = XX" where XX is the
+    // number we're interested in.
+    sscanf(reply, "%*s = %u", &power);
+    return (jint)power;
+}
+
 static jboolean android_net_wifi_setNumAllowedChannelsCommand(JNIEnv* env, jobject clazz, jint numChannels)
 {
     char cmdstr[256];
@@ -538,6 +552,7 @@ static JNINativeMethod gWifiMethods[] = {
     { "startPacketFiltering", "()Z", (void*) android_net_wifi_startPacketFiltering },
     { "stopPacketFiltering", "()Z", (void*) android_net_wifi_stopPacketFiltering },
     { "setPowerModeCommand", "(I)Z", (void*) android_net_wifi_setPowerModeCommand },
+    { "getPowerModeCommand", "()I", (void*) android_net_wifi_getPowerModeCommand },
     { "setNumAllowedChannelsCommand", "(I)Z", (void*) android_net_wifi_setNumAllowedChannelsCommand },
     { "getNumAllowedChannelsCommand", "()I", (void*) android_net_wifi_getNumAllowedChannelsCommand },
     { "setBluetoothCoexistenceModeCommand", "(I)Z",
diff --git a/wifi/java/android/net/wifi/WifiNative.java b/wifi/java/android/net/wifi/WifiNative.java
index c3c519f506819..d9378fcd01746 100644
--- a/wifi/java/android/net/wifi/WifiNative.java
+++ b/wifi/java/android/net/wifi/WifiNative.java
@@ -106,6 +106,8 @@ public class WifiNative {
 
     public native static boolean setPowerModeCommand(int mode);
 
+    public native static int getPowerModeCommand();
+
     public native static boolean setNumAllowedChannelsCommand(int numChannels);
 
     public native static int getNumAllowedChannelsCommand();
diff --git a/wifi/java/android/net/wifi/WifiStateTracker.java b/wifi/java/android/net/wifi/WifiStateTracker.java
index f97f21b7e69c8..c45b480c3af86 100644
--- a/wifi/java/android/net/wifi/WifiStateTracker.java
+++ b/wifi/java/android/net/wifi/WifiStateTracker.java
@@ -1755,6 +1755,8 @@ public class WifiStateTracker extends NetworkStateTracker {
                 case EVENT_DHCP_START:
                     
                     boolean modifiedBluetoothCoexistenceMode = false;
+                    int powerMode = DRIVER_POWER_MODE_AUTO;
+
                     if (shouldDisableCoexistenceMode()) {
                         /*
                          * There are problems setting the Wi-Fi driver's power
@@ -1782,7 +1784,15 @@ public class WifiStateTracker extends NetworkStateTracker {
                     }
                     
                     synchronized (WifiStateTracker.this) {
-                        WifiNative.setPowerModeCommand(DRIVER_POWER_MODE_ACTIVE);
+                        powerMode = WifiNative.getPowerModeCommand();
+                        if (powerMode < 0) {
+                            // Handle the case where supplicant driver does not support
+                            // getPowerModeCommand.
+                            powerMode = DRIVER_POWER_MODE_AUTO;
+                        }
+                        if (powerMode != DRIVER_POWER_MODE_ACTIVE) {
+                            WifiNative.setPowerModeCommand(DRIVER_POWER_MODE_ACTIVE);
+                        }
                     }
                     synchronized (this) {
                         // A new request is being made, so assume we will callback
@@ -1798,7 +1808,9 @@ public class WifiStateTracker extends NetworkStateTracker {
                             NetworkUtils.getDhcpError());
                     }
                     synchronized (WifiStateTracker.this) {
-                        WifiNative.setPowerModeCommand(DRIVER_POWER_MODE_AUTO);
+                        if (powerMode != DRIVER_POWER_MODE_ACTIVE) {
+                            WifiNative.setPowerModeCommand(powerMode);
+                        }
                     }
                     
                     if (modifiedBluetoothCoexistenceMode) {