0 Replies Latest reply on Jun 2, 2019 4:32 AM by praveendeshmane

    usb usb1-port1: disabled by hub (EMI?), re-enabling

    praveendeshmane

      block diagram

       

       

       

      ---Setup---

       

       

      1) We are evaluating using Raspberry Pi Compute Module CM3.

      2) USB-HUB and USB-UART are boarded on the IO board.

      3) USB-HUB is working in Self-power mode.

      4) VBUS-detect of USB-HUB uses the same 3.3V power supply as CM3.

      5) Two LTE modules are connected to USB-HUB via USB-SERIAL and each LTE module takes 2A

       

       

       

       

      ---Protocol---

       

       

      AT commands

       

       

       

       

      ---Problem----

       

       

      The LTE modules which are connected to USB-HUB are disconnecting.This problem occurs only sometimes not always

       

       

      Following are kernel Logs.

       

       

      Kerenl log:

      19:47:58 raspberrypi kernel: [ 9301.001438] usb usb1-port1: disabled by hub (EMI?), re-enabling...

      19:47:58 raspberrypi kernel: [ 9301.001457] usb 1-1: USB disconnect, device number 11

      19:47:58 raspberrypi kernel: [ 9301.001463] usb 1-1.1: USB disconnect, device number 12

      19:47:58 raspberrypi kernel: [ 9301.001668] ftdi_sio ttyUSB2: error from flowcontrol urb

      19:47:58 raspberrypi kernel: [ 9301.001872] ftdi_sio ttyUSB2: FTDI USB Serial Device converter now disconnected from ttyUSB2

      19:47:58 raspberrypi kernel: [ 9301.001906] ftdi_sio 1-1.1:1.0: device disconnected

      19:47:58 raspberrypi kernel: [ 9301.002107] ftdi_sio ttyUSB3: error from flowcontrol urb

      19:47:58 raspberrypi kernel: [ 9301.003371] ftdi_sio ttyUSB3: FTDI USB Serial Device converter now disconnected from ttyUSB3

      19:47:58 raspberrypi kernel: [ 9301.003429] ftdi_sio 1-1.1:1.1: device disconnected

      19:47:58 raspberrypi kernel: [ 9301.010150] ftdi_sio ttyUSB4: FTDI USB Serial Device converter now disconnected from ttyUSB4

      19:47:58 raspberrypi kernel: [ 9301.010212] ftdi_sio 1-1.1:1.2: device disconnected

      19:47:58 raspberrypi kernel: [ 9301.010430] ftdi_sio ttyUSB5: error from flowcontrol urb

      19:47:58 raspberrypi kernel: [ 9301.018012] ftdi_sio ttyUSB5: FTDI USB Serial Device converter now disconnected from ttyUSB5

       

       

       

       

      ---Question---

       

       

       

       

      Any investigation method and solution?