這個平臺的wifip2p也就是wifi Direct（wifi直連）其實是走的hostap功能。

一、問題描述

1.設定-》網路-》無線網路-》，開啟wifi開關。

2.在開啟無線直連,修改密碼以後。

3.不用進入“無線互聯”應用，就會出現描述現象；另外，步驟2中如果不修改密碼、則不出現"設定-》網路-》無線網路，wifi開關無效"。

4.這種情況出現以後“設定-》網路-》無線網路，wifi開關無效”。

其實為wifip2p設定密碼以後Settings應用死掉；後邊第一次開啟時還可以操作“wifi開關”、但timeout ，再之後“wifi開關無效”。

二、問題分析

echo 0 0 0 0 > /proc/sys/kernel/printk
logcat -s WifiEnabler Wifimultisupport WifiPowerSetting WifiStateMachine wpa_supplicant ConnectivityService NetworkSettingsActivity WifiController WifiHW CommandListener WifiP2pService wifi  wpa_supplicant WifiMonitor SupplicantStateTracker WifiP2pSettings WifiMonitor WifiNative-HAL
 

關鍵log

D/WifiP2pSettings( 4253): btn2.setOnClickListener
D/WifiP2pService( 2010): ---Mod Group info, pw: "qqqqqqqq"
I/wpa_supplicant(26602): [CTRL_IFACE_G]SET_NETWORK 0 psk "qqqqqqqq"
D/WifiP2pService( 2010): ---set pw error
D/WifiP2pService( 2010): ---saveConfig
E/wifi    ( 2010): Open file /data/misc/wifi/p2p_supplicant.conf :
......
D/WifiHW  ( 2010): enter func wifi_start_supplicant p2p_supported = 1
E/WifiHW  ( 2010): /data/misc/wifi/p2p_supplicant.conf is all right
E/WifiHW  ( 2010): /data/misc/wifi/wpa_supplicant.conf is all right
I/wpa_supplicant(31183): wpa_supplicant v2.0-devel-4.4.2_rtw_r10999.20140528_debugmsg
I/wpa_supplicant(31183): define REALTEK_WIFI_VENDOR 
I/wpa_supplicant(31183): supp-global-ctrl-iface-init(/data/system/wpa_supplicant/wlan0) (will try fixup): bind(PF_UNIX): Address already in u
se
I/wpa_supplicant(31183): Successfully initialized wpa_supplicant
E/wpa_supplicant(31183): Failed to open config file '/data/misc/wifi/p2p_supplicant.conf', error: Permission denied
E/wpa_supplicant(31183): Failed to read or parse configuration '/data/misc/wifi/p2p_supplicant.conf'.
E/WifiStateMachine( 2010): Failed to start supplicant!
 
[email protected]:/data/misc/wifi # ll
-rw-rw---- system wifi 21 2015-03-30 13:46 entropy.bin
srwxrwx--- wifi wifi 2015-03-30 13:34 p2p0
-rw------- system system 473 2015-03-30 13:38 p2p_supplicant.conf
drwxrwx--- wifi wifi 2015-03-30 13:39 sockets
-rw------- system system 33 2007-01-01 20:01 softap.conf
drwxrwx--- wifi wifi 2007-01-01 20:00 wpa_supplicant
-rw-rw---- system wifi 315 2015-03-30 13:16 wpa_supplicant.conf
 

三、問題解決

修改/data/misc/wifi/p2p_supplicant.conf建立時許可權

hardware/libhardware_legacy/wifi/wifi.c

int ensure_config_file_exists(const char *config_file)
{
    int     ret = 0;
    if (is_config_p2p(config_file)) {
        ret = ensure_config_file(config_file, P2P_CONFIG_TEMPLATE);

    } else {
        ret = ensure_config_file(config_file, SUPP_CONFIG_TEMPLATE);
    }
    //add by tank always make sure config_file has access right.      begin
    /* chmod is needed because open() didn't set permisions properly */
    if (chmod(config_file, 0660) < 0) {
      ALOGE("Error changing permissions of %s to 0660: %s",
                     config_file, strerror(errno));
      unlink(config_file);
      //return -1;
    }

    if (chown(config_file, AID_SYSTEM, AID_WIFI) < 0) {
      ALOGE("Error changing group ownership of %s to %d: %s",
                     config_file, AID_WIFI, strerror(errno));
      unlink(config_file);
      //return -1;
    }
    return ret;
    //end tank always make sure config_file has access right. end
}

補充：

wifip2p的預設SSID等引數設定

system/etc/wifi/p2p_supplicant.conf

三、問題擴充套件wifip2p與Miracast(Wifi Display)