wifi移植后，连接几分钟后自动断开，郁闷中。。。

Question

最近移植了一个sdio的wifi驱动，能够正常启动。
iwconfig wlan2 essid "China-2205"和/sbin/udhcpc -i wlan2可以正确的连接，然后ping 192.168.0.1也可以ping通（wificfg是自己写的一个wifi登陆脚本）

1. root@J2534:/# modprobe libertas_sdio
2. [   22.315000] libertas_sdio: Libertas SDIO driver
3. [   22.315000] libertas_sdio: Copyright Pierre Ossman
4. [   23.610000] libertas: 00:0b:6c:b6:d6:e3, fw 9.70.3p24, cap 0x00000303
5. [   23.610000] libertas: unidentified region code; using the default (USA)
6. [   23.660000] cfg80211: Calling CRDA for country: US
7. [   23.685000] libertas: wlan2: Marvell WLAN 802.11 adapter
8. root@J2534:/# wificfg
9. [   37.790000] ADDRCONF(NETDEV_UP): wlan2: link is not ready
11. Searching wireless AP,please wait...
12. Scanning result:
13.         ESSID                 key on/off
14. (1)    "ChinaNet-CFEb"              on  
15. (2)    "chinaNet"                   off
16. (3)    "router-China 2205"           on  
18. you can also enter r/q for:
19.                            Rescanning(r)
20.                            quit(q)
22. Pls enter the Router's number[(1)?]:3
23. Pls enter key[null ?]:79376
24. The key is 79376 are you sure?[Y/N]
25. [  244.325000] cfg80211: Calling CRDA for country: GB
26. udhcpc (v1.18.4) started
27. Setting IP address 0.0.0.0 on wlan2
28. Sending discover...
29. Sending select for 192.168.0.101...
30. Lease of 192.168.0.101 obtained, lease time 168000
31. Setting IP address 192.168.0.101 on wlan2
32. Deleting routers
33. route: SIOCDELRT: No such process
34. Adding router 192.168.0.1
35. Recreating /etc/resolv.conf
36. Adding DNS server 202.96.134.133
37. Adding DNS server 202.96.128.68
39. Connecting is successful!
40. root@J2534:/# ifconfig
41. wlan2     Link encap:Ethernet  HWaddr 00:0B:6C:B6:D6:E3  
42.           inet addr:192.168.0.101  Bcast:255.255.255.255  Mask:255.255.255.0
43.           inet6 addr: fe80::20b:6cff:feb6:d6e3/64 Scope:Link
44.           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
45.           RX packets:115 errors:0 dropped:0 overruns:0 frame:0
46.           TX packets:14 errors:0 dropped:0 overruns:0 carrier:0
47.           collisions:0 txqueuelen:1000
48.           RX bytes:11378 (11.1 KiB)  TX bytes:3104 (3.0 KiB)

复制代码但过了一阵后（3 minutes~10 minutes），就自动断开了连接。

2. root@J2534:/# [  296.035000] cfg80211: Calling CRDA to update world regulatory domain
4. root@J2534:/# dmesg|grep cfg80211
5. [  758.790000] cfg80211: Calling CRDA for country: GB
6. [  791.595000] cfg80211: All devices are disconnected, going to restore regulatory settings
7. [  791.595000] cfg80211: Restoring regulatory settings
8. [  791.595000] cfg80211: Calling CRDA to update world regulatory domain

复制代码看内核里的代码net/wireless/reg.c中，应该是到了这里：

2. static int call_crda(const char *alpha2)
3. {
4.         char country_env[9 + 2] = "COUNTRY=";
5.         char *envp[] = {
6.                 country_env,
7.                 NULL
8.         };
10.         if (!is_world_regdom((char *) alpha2))
11.                 printk(KERN_INFO "cfg80211: Calling CRDA for country: %c%c\n",
12.                         alpha2[0], alpha2[1]);
13.         else
14.                 printk(KERN_INFO "cfg80211: Calling CRDA to update world "
15.                         "regulatory domain\n");
17.         /* query internal regulatory database (if it exists) */
18.         reg_regdb_query(alpha2);
20.         country_env[8] = alpha2[0];
21.         country_env[9] = alpha2[1];
23.         return kobject_uevent_env(®_pdev->dev.kobj, KOBJ_CHANGE, envp);
24. }

复制代码但一直看不懂究竟是啥意思？

从man crda中得知，crda是由kernel触发和发出的udev事件给userspace。
下面是摘自man crda中的一段：

2. Description
3.        crda is the Linux wireless central regulatory domain agent.  crda is intended to be used by udev scripts and
4.        should not be run manually unless debugging udev scripts.  crda is triggered to run by the kernel by sending a
5.        udev event upon a new regulatory domain change. Regulatory domain changes are triggered by the wireless kernel
6.        subsystem (upon initialization and on reception of country IEs), wireless drivers, or userspace (see iw ). Upon a
7.        regulatory domain change the kernel sends a udev change event for the regulatory platform. The kernel ignores reg‐
8.        ulatory domains sent to it if it does not expect them. The regulatory domain is read by crda from the regula‐
9.        tory.bin file.

复制代码哪位大侠对mdev比较了解或遇见过类似情况的，麻烦指点下，感谢了！