RPi USB disconnect problem

Troubleshooting
1

Hello

For some time I have a problem with the unexpected disconnection of devices connected to the USB ports. I have 2 rs232-USB converters connected to RPi (powered by USB) and a touch overlay - everything disconnects in an instant, ports disappear and do not reappear, it is necessary to reconnect the USB or restart the system.

I will only add that a few days ago I had a problem with the power supply on this device (‘Under-voltage detected! (0x00050005)’ warnings) - I found the cause and eliminated this problem.

Below is a fragment of the logs:

Sep 20 05:30:14 DietPi kernel: [366242.521139] xhci_hcd 0000:01:00.0: ERROR unknown event type 0
Sep 20 05:30:19 DietPi kernel: [366247.529699] xhci_hcd 0000:01:00.0: xHCI host not responding to stop endpoint command.
Sep 20 05:30:19 DietPi kernel: [366247.529708] xhci_hcd 0000:01:00.0: USBSTS:
Sep 20 05:30:19 DietPi kernel: [366247.530289] usb 1-1: USB disconnect, device number 2
Sep 20 05:30:19 DietPi kernel: [366247.530302] usb 1-1.1: USB disconnect, device number 3
Sep 20 05:30:19 DietPi kernel: [366247.754395] usb 1-1.3: USB disconnect, device number 4
Sep 20 05:30:19 DietPi kernel: [366247.755593] ftdi_sio ttyUSB0: FTDI USB Serial Device converter now disconnected from ttyUSB0
Sep 20 05:30:19 DietPi kernel: [366247.755721] ftdi_sio 1-1.3:1.0: device disconnected
Sep 20 05:30:19 DietPi kernel: [366247.756879] usb 1-1.4: USB disconnect, device number 5
Sep 20 05:30:19 DietPi kernel: [366247.758008] ftdi_sio ttyUSB1: FTDI USB Serial Device converter now disconnected from ttyUSB1
Sep 20 05:30:19 DietPi kernel: [366247.758090] ftdi_sio 1-1.4:1.0: device disconnected

I would be grateful for any suggestions.
Logs attached - problem occurred September 20, 05:30 am.
tts_jd_usb_log.zip (82.9 KB)

2

Are the USB devices now powered externally that you resolved the under-voltage issue? Generally it is not safe to power 2.5" drives via USB only on RPi as all ports share a combined maximum of 1.2A (6W), which is easily hit on power usage peaks.

3

The voltage drop has been eliminated by cranking the voltage up to 5.2v
As I mentioned to RPi, I have rs232-usb converters and a touch overlay.
Below is the result of the command: usb-devices | grep ‘Product=|MxPwr’

S:  Product=xHCI Host Controller
C:  #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=0mA
S:  Product=USB2.0 Hub
C:  #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=100mA
S:  Product=Atmel maXTouch Digitizer
C:  #Ifs= 3 Cfg#= 1 Atr=a0 MxPwr=100mA
S:  Product=FT232R USB UART
C:  #Ifs= 1 Cfg#= 1 Atr=a0 MxPwr=90mA
S:  Product=USB <-> RS485 (MP01512A)
C:  #Ifs= 1 Cfg#= 1 Atr=a0 MxPwr=500mA
S:  Product=xHCI Host Controller
C:  #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=0mA

However, I am aware that this does not show the actual power consumption.

I will also mention that from time to time(rarely) there are errors like below:

[365671.127257] ftdi_sio ttyUSB1: failed to get modem status: -110
[72684.751053] ftdi_sio ttyUSB0: failed to get modem status: -75
[275979.593438] ftdi_sio ttyUSB1: failed to get modem status: -32

Can you tell from the above logs? I have searched a lot of topics in various forums and the tip is for bugs: kernel / driver / FTDI chip crashing.
Is there any idea that I could clearly identify the cause of the problems?

4

Nice command actually, I didn’t know about that way to derive the theoretical maximum current of a USB device. Hmm, 500 + 100 + 100 + 90 = 790 mA. With 5.2V (on USB?) this is 4.108W, so at least close to the theoretical maximum of 6W. Not sure if there are either peaks on power consumption or minimum peaks on power provision by the RPi which may lead to such connection errors.

I think the RPi forum may be a good place to reach a wider range or experienced RPi users and devs: https://forums.raspberrypi.com/
Feel free to ping me there and/or reference this issue.