praveendeshmane
Posts: 2
Joined: Sun Jun 02, 2019 8:52 am

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

Sun Jun 02, 2019 8:59 am

Image


---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 total consumption of power is 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?
Last edited by praveendeshmane on Mon Jun 03, 2019 6:11 am, edited 1 time in total.

aBUGSworstnightmare
Posts: 1442
Joined: Tue Jun 30, 2015 1:35 pm

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

Sun Jun 02, 2019 7:28 pm

Sorry, but there's either something wrong in your block diagram or your description!

Your block diagram shows a 5V supply which is powering the whole unit ; 3.3V and 1.8V are also generated from this 5V rail.
USB hub is connected to this rail as well.
This 5V rail is able to supply 3.5A.

Now you say each LTE module can draw up to 2A! So, how to make this happen if your total available current is 3.5A only (not considering power requiremt of the Compute Module itself)?

praveendeshmane
Posts: 2
Joined: Sun Jun 02, 2019 8:52 am

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

Mon Jun 03, 2019 6:13 am

sorry, total consumption is 2A not for each model.

gsh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 1421
Joined: Sat Sep 10, 2011 11:43 am

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

Mon Jun 03, 2019 6:18 am

Have you checked the power supplies for any noise? It may be a problem with not having sufficient decoupling caps on the board
--
Gordon Hollingworth PhD
Raspberry Pi - Director of Software Engineering

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