Bug 545638

Summary: modem-manager trying to control non-wireless modem
Product: [Fedora] Fedora Reporter: Peter F. Patel-Schneider <pfpschneider>
Component: ModemManagerAssignee: Dan Williams <dcbw>
Status: CLOSED DUPLICATE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: low    
Version: 12CC: dcbw
Target Milestone: ---   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2010-01-18 22:07:06 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Peter F. Patel-Schneider 2009-12-09 01:02:19 UTC
Description of problem:

I have a USB US Robotics modem - a real one that connects to wired phone lines.  It appears that modem-manager is trying to manage it, but this is not a wireless modem, so it is not doing anything useful, and is preventing me from using, e.g., wvdial.

Version-Release number of selected component (if applicable):

0.2 (from yum info ModemManager)

How reproducible:

Always (with this hardware)

Steps to Reproduce:
1. Connect USB US Robotics modem
2. Try to use wvdial
3.
  
Actual results:

--- /var/log/messages

Dec  8 14:59:03 idefix kernel: usb 1-5: new high speed USB device using ehci_hcd and address 5
Dec  8 14:59:03 idefix kernel: usb 1-5: New USB device found, idVendor=0baf, idProduct=0303
Dec  8 14:59:03 idefix kernel: usb 1-5: New USB device strings: Mfr=1, Product=2, SerialNumber=10
Dec  8 14:59:03 idefix kernel: usb 1-5: Product: USB Modem
Dec  8 14:59:03 idefix kernel: usb 1-5: Manufacturer: U.S.Robotics
Dec  8 14:59:03 idefix kernel: usb 1-5: SerialNumber: 0000002
Dec  8 14:59:03 idefix kernel: usb 1-5: configuration #2 chosen from 1 choice
Dec  8 14:59:03 idefix kernel: cdc_acm 1-5:2.0: ttyACM2: USB ACM device
Dec  8 14:59:03 idefix modem-manager: (ttyACM2) opening serial device...

idefix 102> wvdial
--> WvDial: Internet dialer version 1.60
--> Cannot open /dev/ttyACM2: Device or resource busy
--> Cannot open /dev/ttyACM2: Device or resource busy
--> Cannot open /dev/ttyACM2: Device or resource busy

Expected results:

wvdial dials and opens a connection

Additional info:

A workaround should be to disable modem-manager, but I can't even figure out how to do that.

Comment 1 Dan Williams 2009-12-09 03:04:13 UTC
This is apparently a kernel issue in 2.6.31 where the modem or kernel blocks modem-manager's serial port communication.  What *should* be happening is that modem-manager probes the device, finds it does not support mobile broadband, and then forgets about it.  There are other reports of this problem happening with mobile broadband devices (https://bugzilla.redhat.com/show_bug.cgi?id=533716) so it's not unique to your device.

Comment 2 Dan Williams 2010-01-18 22:07:06 UTC

*** This bug has been marked as a duplicate of bug 533716 ***