TI中文支持网我现在有一款产品使用的am437x芯片，用的linux系统，现在接了一个华为usb 4G模块，硬件上usb 4g模块是单独供电，休眠的时候4G模块是没有断电的,想要实现休眠后通过网络唤醒,现在问题如下:
am437x休眠后，感觉整个usb控制器断电了,休眠唤醒部分log如下:
root@am437x-evm:/# echo mem > /sys/power/state[ 941.006300] PM: Syncing filesystems … done.
[ 941.019368] Freezing user space processes … (elapsed 0.001 seconds) done.
[ 941.035127] Freezing remaining freezable tasks … (elapsed 0.001 seconds) done.
[ 941.044099] Suspending console(s) (use no_console_suspend to debug)
[ 941.057618] PM: suspend of devices complete after 6.185 msecs
[ 941.060357] PM: late suspend of devices complete after 2.708 msecs
[ 941.063676] PM: noirq suspend of devices complete after 3.290 msecs
[ 941.063686] PM: Successfully put all powerdomains to target state
[ 941.067026] PM: noirq resume of devices complete after 3.227 msecs
[ 941.069164] PM: early resume of devices complete after 1.718 msecs
[ 941.177354] usb usb1: root hub lost power or was reset
[ 941.177372] usb usb2: root hub lost power or was reset
[ 941.180330] usb usb3: root hub lost power or was reset
[ 941.180348] usb usb4: root hub lost power or was reset
[ 941.294983] PM: resume of devices complete after 225.783 msecs
[ 941.361580] Restarting tasks …[ 941.365052] usb 1-1: USB disconnect, device number 2
[ 941.370425] cdc_ether 1-1:2.0 usb0: unregister 'cdc_ether' usb-xhci-hcd.0.auto-1, CDC Ethernet Device
[ 941.393051] done.
root@am437x-evm:/# [ 941.466452] option1 ttyUSB1: GSM modem (1-port) converter now disconnected from ttyUSB1
[ 941.521233] option 1-1:2.2: device disconnected
[ 941.549256] option1 ttyUSB2: GSM modem (1-port) converter now disconnected from ttyUSB2
[ 941.588786] option 1-1:2.3: device disconnected
[ 941.605284] option1 ttyUSB3: GSM modem (1-port) converter now disconnected from ttyUSB3
[ 941.635840] option 1-1:2.4: device disconnected
[ 941.650996] option1 ttyUSB4: GSM modem (1-port) converter now disconnected from ttyUSB4
[ 941.676776] option 1-1:2.5: device disconnected
[ 941.691900] option1 ttyUSB5: GSM modem (1-port) converter now disconnected from ttyUSB5
[ 941.717909] option 1-1:2.6: device disconnected
[ 945.492586] usb 1-1: new high-speed USB device number 3 using xhci-hcd
[ 945.699092] cdc_ether 1-1:2.0 usb0: register 'cdc_ether' at usb-xhci-hcd.0.auto-1, CDC Ethernet Device, 02:1e:10:1f:00:00
[ 945.720774] option 1-1:2.2: GSM modem (1-port) converter detected
[ 945.729806] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB0
[ 945.747506] option 1-1:2.3: GSM modem (1-port) converter detected
[ 945.771812] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB1
[ 945.810413] option 1-1:2.4: GSM modem (1-port) converter detected
[ 945.831348] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB2
[ 945.841605] option 1-1:2.5: GSM modem (1-port) converter detected
[ 945.854758] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB3
[ 945.869764] option 1-1:2.6: GSM modem (1-port) converter detected
[ 945.877664] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB4
我们使用的pppd进行拨号，休眠后pppd断开了，同时服务器端检测到tcp链接也断了(我们使用的tcp通讯，服务器加了keepalive属性)
这个时候无法确定，4g模块是否有收到数据,同时唤醒后pppd会进行重拨，这个时候会导致ip地址发生变化.
看了内核usb相关文件，如果打开了usb remote wake up可以保证usb设备号不发生变化，如果设备号不发生变化，有可能pppd不会断，也就不会重拨
设置了
./sys/devices/platform/44000000.ocp/48380000.omap_dwc3/48390000.usb/xhci-hcd.0.auto/usb1/1-1/power/persist
为1
同时设置了
./sys/devices/platform/44000000.ocp/48380000.omap_dwc3/48390000.usb/xhci-hcd.0.auto/usb1/1-1/power/wakeup
为enabled
但是似乎是没有作用,休眠唤醒的打印信息仍然跟上面的打印信息一样没有变化，华为usb 4g模块支持usb remote wake up相关设置也已经打开
我想问下am437x是否支持usb remote wake up 如果支持如何打开?
如果不支持 休眠后具体通讯流程应该是怎么样的，如何保证唤醒后ip地址不发生变化.
谢谢.
HG：
请到
Sitara™ Cortex-A8 和 ARM9 微处理器
提问
