On Sat, 25 Jan 2020, JH wrote: > Hi Alan, > > On 1/25/20, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > > On Fri, 24 Jan 2020, JH wrote: > > > >> Hi, > >> > >> I am running kernel 4.19.75 on iMX6 with a uBlox SARA-R4 LTE modem, > >> the modem manager is oFono, connect manager is connman. It could > >> connect to LTE between half hours to hours, then it dropped LTE > >> connection randomly, here are error messages, what could cause the > >> qmi_wwan status received: -71 and qmi_wwan usb_submit_urb failed with > >> result -19 errors? > > > > The most likely cause is that the modem's firmware crashed, or it > > disconnected itself electronically from the USB bus. Or else somebody > > unplugged the USB cable. > > There is no physical USB cable to connect to the device, the device > USB power supply is from its internal DC source which converted and > connected from external normal AC power. If it is a USB electronic > fault, the firmware is using Linux kernel USB, oFono and connman, > which one could be the source to cause the crash, Linux kernel USB > driver, oFono or connman? I have no idea. In fact, I know nothing at all about qmi_wwan, oFono, or connman. Have you tried looking at the kernel log on the device to see if it gives any clues? > I am diagnosing the issue, I try to narrow down the source to cause > the problem, is it fair to say that the higher layer software package > including oFono, connman or our software applications is unlikely the > source to cause the problem? No, it isn't fair to say that. The problem could lie anywhere. Alan Stern > Appreciate if you could advise which components could be the issue, > what could be a solution to fix it. > > Thank you. > > Kind regards, > > - jh > > > Alan Stern > > > >> > >> [ 1018.944840] usb 1-1: USB disconnect, device number 2 > >> [ 1019.072845] option1 ttyUSB0: GSM modem (1-port) converter now > >> disconnected from ttyUSB0 > >> [ 1019.130834] option 1-1:1.0: device disconnected > >> [ 1019.142012] qmi_wwan 1-1:1.3: nonzero urb status received: -71 > >> [ 1019.147909] qmi_wwan 1-1:1.3: wdm_int_callback - 0 bytes > >> [ 1019.153254] qmi_wwan 1-1:1.3: wdm_int_callback - usb_submit_urb > >> failed with result -19 > >> [ 1019.228197] option1 ttyUSB1: GSM modem (1-port) converter now > >> disconnected from ttyUSB1 > >> [ 1019.274475] option 1-1:1.2: device disconnected > >> [ 1019.340442] qmi_wwan 1-1:1.3 wwan0: unregister 'qmi_wwan' > >> usb-ci_hdrc.1-1, WWAN/QMI device > >> [ 1022.827992] usb 1-1: new high-speed USB device number 3 using ci_hdrc > >> [ 1023.057165] option 1-1:1.0: GSM modem (1-port) converter detected > >> [ 1023.097815] usb 1-1: GSM modem (1-port) converter now attached to > >> ttyUSB0 > >> [ 1023.157293] option 1-1:1.2: GSM modem (1-port) converter detected > >> [ 1023.178163] usb 1-1: GSM modem (1-port) converter now attached to > >> ttyUSB1 > >> [ 1023.201251] qmi_wwan 1-1:1.3: cdc-wdm0: USB WDM device > >> [ 1023.243783] qmi_wwan 1-1:1.3 wwan0: register 'qmi_wwan' at > >> usb-ci_hdrc.1-1, WWAN/QMI device, 16:ed:38:aa:c5:90 > >> > >> Thank you. > >> > >> Kind regards, > >> > >> - jh > > > > >
