藍牙和wifi的一個奇怪問題之解決

http://www.oschina.net/question/158589_55569

如下是我本身關於這個問題的詳細分析過程：

問題：bluetooth必須在wifi開啓後才能正常開啓。

目標：bluetooth的開啓不受wifi影響。

現象：

先打開wifi，再打開bluetooth。

I/wpa_supplicant( 2748): CTRL-EVENT-STATE-CHANGE id=-1 state=1

V/WifiMonitor( 2359): Event [CTRL-EVENT-STATE-CHANGE id=-1 state=1]

V/WifiStateTracker( 2359): Changing supplicant state: INACTIVE ==> INACTIVE

D/BluetoothService( 2359): Bluetooth state 10 -> 11

V/BluetoothEventRedirector( 2533): Received android.bluetooth.adapter.action.STATE_CHANGED

init: no such service 'hciattach'

I/bluedroid( 2359): Starting hciattach daemon

I/bluedroid( 2359): Starting bluetoothd deamon

E/BluetoothEventLoop.cpp( 2359): event_filter: Received signal org.freedesktop.DBus:NameAcquired from /org/freedesktop/DBus

D/BluetoothService( 2359): found 1 bonded devices

I/BluetoothDeviceProfileState( 2359): Entering ACL Connected state with: -1

D/BluetoothService( 2359): Bluetooth state 11 -> 12

V/BluetoothEventRedirector( 2533): Received android.bluetooth.adapter.action.STATE_CHANGED

D/BluetoothService( 2359): updateDeviceServiceChannelCache(E4:B0:21:58:18:53)

I/bluetooth_ScoSocket.cpp( 2439): Listening SCO socket...

D/BluetoothService( 2359):      uuid(system): 00001105-0000-1000-8000-00805f9b34fb 3

I/BtOppRfcommListener( 2571): Accept thread started on channel 12

D/BluetoothService( 2359): Registering hfag record

 

打開bluetooth，不打開wifi

D/BluetoothService( 2359): Bluetooth state 10 -> 11

V/BluetoothEventRedirector( 2533): Received android.bluetooth.adapter.action.STATE_CHANGED

init: no such service 'hciattach'

I/bluedroid( 2359): Starting hciattach daemon

D/dalvikvm( 2571): GC_EXPLICIT freed 194K, 49% free 2802K/5447K, external 716K/1038K, paused 104ms

 

 

打開bluetooth，而後打開wifi

D/BluetoothService( 2359): Bluetooth state 10 -> 11

V/BluetoothEventRedirector( 2533): Received android.bluetooth.adapter.action.STATE_CHANGED

init: no such service 'hciattach'

I/bluedroid( 2359): Starting hciattach daemon

D/dalvikvm( 2571): GC_EXPLICIT freed 120K, 49% free 2782K/5447K, external 716K/1038K, paused 89ms

WLAN FW already running! Skip FW download

WLAN FW is active

I/bluedroid( 2359): Starting bluetoothd deamon

W/Netd    ( 2215): action=1, iface=mlan0

D/Tethering( 2359): mlan0 is not a tetherable iface, ignoring

D/NetdConnector( 2359): RCV <- {600 Iface added mlan0}

W/Netd    ( 2215): action=5, iface=mlan0

D/Tethering( 2359): interfaceLinkStatusChanged mlan0, false

D/NetdConnector( 2359): RCV <- {600 Iface linkstate mlan0 down}

W/Netd    ( 2215): action=1, iface=uap0

D/Tethering( 2359): uap0 is not a tetherable iface, ignoring

W/Netd    ( 2215): action=5, iface=uap0

D/Tethering( 2359): interfaceLinkStatusChanged uap0, false

D/NetdConnector( 2359): RCV <- {600 Iface added uap0}

D/NetdConnector( 2359): RCV <- {600 Iface linkstate uap0 down}

I/BluetoothEventLoop.cpp( 2359): agent_event_filter: Received method org.bluez.Agent:Release

D/BluetoothService( 2359): found 1 bonded devices

D/BluetoothService( 2359): Bluetooth state 11 -> 12

V/BluetoothEventRedirector( 2533): Received android.bluetooth.adapter.action.STATE_CHANGED

I/bluetooth_ScoSocket.cpp( 2439): Listening SCO socket...

 

分析：

定位關鍵代碼

 

    if (set_bluetooth_power(1) < 0) goto out;

 

    LOGI("Starting hciattach daemon");

    if (property_set("ctl.start", "hciattach") < 0) {

        LOGE("Failed to start hciattach");

        goto out;

    }

 

    // Try for 10 seconds, this can only succeed once hciattach has sent the

    // firmware and then turned on hci device via HCIUARTSETPROTO ioctl

    for (attempt = 1000; attempt > 0;  attempt--) {

        hci_sock = create_hci_sock();

        if (hci_sock < 0) goto out;

 

        if (!ioctl(hci_sock, HCIDEVUP, HCI_DEV_ID)) {

            break;

        }

        close(hci_sock);

        usleep(10000);  // 10 ms retry delay

    }

    if (attempt == 0) {

        LOGE("%s: Timeout waiting for HCI device to come up", __FUNCTION__);

        goto out;

    }

 

    LOGI("Starting bluetoothd deamon");

    if (property_set("ctl.start", "bluetoothd") < 0) {

        LOGE("Failed to start bluetoothd");

        goto out;

    }

 

 

在標紅的代碼兩端添加打印，看是不是該段代碼阻塞了藍牙的打開。

I/bluedroid( 2385): Starting hciattach daemon

I/bluedroid( 2385): <<James.C>> --- Turning on HCI device

D/dalvikvm( 2583): GC_EXPLICIT freed 170K, 49% free 2800K/5447K, external 716K/1038K, paused 89ms

D/dalvikvm( 2385): GC_EXPLICIT freed 434K, 38% free 4808K/7751K, external 1867K/3065

並無LOGI("<<James.C>> --- End of Turning on HCI device: attemp = %d", attempt);的打印。

=》多是卡死在for循環了。

=》多是直接走out了。

須要進行確認。

 

 

 

在for循環中添加打印：

LOGI("<<James.C>> --- Turning on HCI device");

    for (attempt = 1000; attempt > 0;  attempt--) {

        hci_sock = create_hci_sock();

        LOGI("<<James.C>> --- hci_sock = %d, attempt = %d", hci_sock, attempt);

        if (hci_sock < 0) goto out;

 

        if (!ioctl(hci_sock, HCIDEVUP, HCI_DEV_ID)) {

            break;

        }

        close(hci_sock);

        usleep(10000);  // 10 ms retry delay                                                                                                                           

    }

LOGI("<<James.C>> --- End of Turning on HCI device: attemp = %d", attempt);

if (attempt == 0) {

        LOGE("%s: Timeout waiting for HCI device to come up", __FUNCTION__);

        goto out;

    }

一直在循環。

 

經過for循環前的註釋，初步定位爲hciattach服務的問題。Grep關鍵詞，主要是在如下文件中：

./device/fsl/imx51_3stack/mxc_bt.sh:/system/bin/hciattach -n -s 921600 /dev/ttymxc1 bcsp 921600;

./device/fsl/imx51_3stack/init.rc:service hciattach /system/bin/logwrapper /system/bin/sh /system/etc/bluez/mxc_bt.sh

經確認，不是這個緣由，由於fsl目錄下的東西沒有被執行。

 

HCI device沒法經過ioctl打開

=》ioctl(hci_sock, HCIDEVUP, HCI_DEV_ID)失敗了

=》查看hci socket的ioctl

 

static int hci_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)

{

case HCIDEVUP:

                   if (!capable(CAP_NET_ADMIN))

                            return -EACCES;

                   return hci_dev_open(arg);

}

其實就是權限檢查+設備打開。

增長打印

case HCIDEVUP:

                if (!capable(CAP_NET_ADMIN))

                        return -EACCES;

                printk("<<James.C>> --- hci_dev_open(arg) \n");

                ret = hci_dev_open(arg);   

                printk("<<James.C>> --- ret = %d \n", ret);

                return ret;

 

目標：經過打印看是權限不對仍是打開hci設備出錯。

 

<<James.C>> --- ret = -110

<<James.C>> --- hci_dev_open(arg)

I/bluedroid( 2386): <<James.C>> --- hci_sock = 164, attempt = 997

#define     ETIMEDOUT    110  /* Connection timed out */

 

 

因而問題就定位爲HCI device作request時產生了timeout的錯誤。

int hci_dev_open(__u16 dev)

{

ret = __hci_request(hdev, hci_init_req, 0,

                                               msecs_to_jiffies(HCI_INIT_TIMEOUT));//10s timeout

}

執行hci_init_req(hdev, 0)產生了超時

 

=》對hci device進行考察，找出超時緣由。（android hci; Linux hci; hci device;）

=》wifi開啓時，哪些東西會影響hci device？

 

猜測：有多是固件加載的問題。打開藍牙時沒有對固件進行加載。

已經排除此可能。

 

猜測：是否是nh387尚未上電？

Nh387已經成功初始化。

 

猜測：HCI daemon沒有啓動，或者確實文件。

方法：瞭解HCI通訊機制及其須要的文件。

在bt_main.c中有以下函數：

/**

 *  @brief This function send module cfg cmd to firmware

 *

 *  Command format:

 *  +--------+--------+--------+--------+--------+--------+--------+

 *  |     OCF OGF     | Length |                Data               |

 *  +--------+--------+--------+--------+--------+--------+--------+

 *  |     2-byte      | 1-byte |               4-byte              |

 *  +--------+--------+--------+--------+--------+--------+--------+

 * 

 *  @param priv    A pointer to bt_private structure

 *  @param subcmd  sub command

 *  @return             BT_STATUS_SUCCESS or BT_STATUS_FAILURE

 */

int

bt_send_module_cfg_cmd(bt_private * priv, int subcmd)

 

它在執行以下語句時失敗了

ret = bt_send_module_cfg_cmd(priv, MODULE_BRINGUP_REQ);

    if (ret < 0) {

        PRINTM(FATAL, "Module cfg command send failed!\n");

        goto err_init_fw;

}

 

這就頗有多是問題所在。提升PRINTM打印級別，看bt模塊是否正確的初始化其firmware。

Firmware初始化正常了，可是bringup module這個request卻執行失敗。

bt_send_module_cfg_cmd(priv, MODULE_BRINGUP_REQ);這句話會如何執行？

 

 

用舊的驅動和firmware：

加載藍牙驅動時，沒有timeout的錯誤，也就是說module_bringup_req執行成功了。可是，依然是不能打開藍牙，現象和新的藍牙驅動同樣。

另外，使用舊的wifi驅動，系統啓動後，」setting」 -> 「open wifi」會致使down機。

 

 

 

還原SDIO驅動

ok。。。。。。。。我擦！