开启wifi错误
最近遇到一个wifi问题，同一个手机，由eng版本升级到user版本后，去打开wifi，wifi一直处于正在打开状态，打开不了。打印log显示以下错误：
E/WifiStateMachine( 452): Failed to start supplicant!
D/StateMachine( 452): handleMessage: X
D/StateMachine( 452): handleMessage: E msg.what=131073
D/StateMachine( 452): processMsg: DriverLoadedState
D/WifiStateMachine( 452): DriverLoadedState{ what=131073 when=-10s843ms arg1=2 }
D/StateMachine( 452): processMsg: DefaultState
D/WifiStateMachine( 452): DefaultState{ what=131073 when=-10s843ms arg1=2 }
D/StateMachine( 452): handleMessage: X
D/StateMachine( 452): handleMessage: E msg.what=131083
D/StateMachine( 452): processMsg: DriverLoadedState
D/WifiStateMachine( 452): DriverLoadedState{ what=131083 when=-10s843ms }
E/ ( 452): fopen failed: /dev/cpuctl/ux/tasks, Permission denied
I/ActivityThread( 1572): Pub com.google.android.music.athome: com.google.android.music.athome.AtHomeContentProvider
I/ActivityThread( 1572): Pub com.google.android.music.MusicContent: com.google.android.music.store.MusicContentProvider
I/MusicStore( 1572): Database version: 44
W/CommandListener( 128): Failed to retrieve HW addr for wlan0 (No such device)
E/WifiStateMachine( 452): Unable to change interface settings: java.lang.IllegalStateException: command '10 interface setcfg wlan0 0.0.0.0 0 down' failed with '400 10 Failed to set address (No such device)'
D/wpa_supplicant( 1611): wpa_supplicant v2.0-devel-4.1.2
D/wpa_supplicant( 1611): Add randomness: count=1 entropy=0
看到W/CommandListener( 128): Failed to retrieve HW addr for wlan0 (No such device)
错误，以为是没写地址导致的，去about phone查看wifi地址，果然是不可用的，但是用QXDM读wifi地址（NV项为4678项），地址是有的，也就是说引起wifi开启不了的原因还是因为Failed to start supplicant!，导致读取地址也是失败的。
start pupplicant是由WifiStateMachine直接调用wifinative的startSupplicant方法来处理的，最后调到wifi,c的wifi_start_supplicant
int wifi_start_supplicant(int p2p_supported)
{
char supp_status[PROPERTY_VALUE_MAX] = {'\0'};
int count = 200; /* wait at most 20 seconds for completion */
#ifdef HAVE_LIBC_SYSTEM_PROPERTIES
const prop_info *pi;
unsigned serial = 0, i;
char supp_rdy_status[PROPERTY_VALUE_MAX] = "";
const prop_info *rdy_pi = NULL;
int rdy_loop_count = 0;
#endif
if (p2p_supported) {
strcpy(supplicant_name, P2P_SUPPLICANT_NAME);
strcpy(supplicant_prop_name, P2P_PROP_NAME);
/* Ensure p2p config file is created */
if (ensure_config_file_exists(P2P_CONFIG_FILE) < 0) {
ALOGE("Failed to create a p2p config file");
return -1;
}
} else {
strcpy(supplicant_name, SUPPLICANT_NAME);
strcpy(supplicant_prop_name, SUPP_PROP_NAME);
}
/* Check whether already running */
if (property_get(supplicant_name, supp_status, NULL)
&& strcmp(supp_status, "running") == 0) {
return 0;
}
/* Before starting the daemon, make sure its config file exists */
if (ensure_config_file_exists(SUPP_CONFIG_FILE) < 0) {
ALOGE("Wi-Fi will not be enabled");
return -1;
}
if (ensure_entropy_file_exists() < 0) {
ALOGE("Wi-Fi entropy file was not created");
}
/* Clear out any stale socket files that might be left over. */
wifi_wpa_ctrl_cleanup();
/* Reset sockets used for exiting from hung state */
for (i=0; i running => stopped (i.e.,
* it start up, but fails right away) from the case in which
* it starts in the stopped state and never manages to start
* running at all.
*/
pi = __system_property_find(supplicant_prop_name);
if (pi != NULL) {
serial = pi->serial;
}
#endif
property_get("wifi.interface", primary_iface, WIFI_TEST_INTERFACE);
property_set("ctl.start", supplicant_name);
sched_yield();
while (count-- > 0) {
#ifdef HAVE_LIBC_SYSTEM_PROPERTIES
if (pi == NULL) {
pi = __system_property_find(supplicant_prop_name);
}
if (pi != NULL) {
__system_property_read(pi, NULL, supp_status);
if (strcmp(supp_status, "running") == 0) {
for (rdy_loop_count = 0; rdy_loop_count < 15000/RDY_WAIT_MS;
rdy_loop_count ++) {
if (rdy_pi == NULL) {
rdy_pi = __system_property_find(SUPP_RDY_PROP_NAME);
} else {
__system_property_read(rdy_pi, NULL, supp_rdy_status);
if (strcmp(supp_rdy_status, "1") == 0)
{
return 0;
}
}
usleep (RDY_WAIT_MS * 1000);
}
return -1;
} else if (pi->serial != serial &&
strcmp(supp_status, "stopped") == 0) {
return -1;
}
}
#else
if (property_get(supplicant_prop_name, supp_status, NULL)) {
if (strcmp(supp_status, "running") == 0)
return 0;
}
#endif
usleep(100000);
}
return -1;
}
查看开不了wifi的手机，各种配置文件均正常。再往下分析好像也没有什么问题。
查看下一个错误信息：W/CommandListener( 128): Failed to retrieve HW addr for wlan0 (No such device)
网上搜索了下这个错误，竟然还是很多人遇到这样的错误，有人建议
Check that you have the modules in /system/lib/module，说是这个文件下面多了两个驱动文件，删除就可以了，但是查看问题手机和正常手机的modules下面的文件是一样的。更多的版本是
1：在刷rom之前刷boot.img
2：wipe
3：刷rom
问题手机是升级了软件版本开不了的，按照上面这个所说，想到了先下载了一个能开启的版本，然后一步步升级软件版本，先写了boot.img,然后是system.img，userdata.img,这几个每次写完都看一下wifi是否能打开，结果这三个都是正常的。接下来写了persist.img，这个写进去后，wifi开不了了。找到了是有这个persist,img引起的。之前调wifi参数时，曾经修改过手机里persist/bdata.bin这个文件。然后看了下问题手机里persist这个目录下面没有bdata.bin这个文件，push进去一个bdata.bin，wifi就能正常开启，问题解决。
同一套代码，编译成eng版本，wifi是正常，编译成user版本，persist目录下就没有了bdata.bin这个文件。查看makefile等信息，都没有对版本编译做限制的条件编译，这个问题不知道是什么原因。