Bug 15811

Summary: ark3116 changes minor if open across suspend
Product: Drivers Reporter: Ferenc Wágner (wferi)
Component: USBAssignee: Greg Kroah-Hartman (greg)
Status: RESOLVED WILL_NOT_FIX    
Severity: normal CC: alan, rui.zhang, tianyu.lan
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 3.4 Subsystem:
Regression: No Bisected commit-id:
Bug Depends on:    
Bug Blocks: 56331    

Description Ferenc Wágner 2010-04-19 11:45:52 UTC 
My USB serial dongle is driven by ark3116. After plugging it in, it's assigned to node /dev/ttyUSB0. However, if it's opened by some process when I suspend the machine, after resume it appears as /dev/ttyUSB1. It changes back and forth between ttyUSB0 and ttyUSB1 if it's opened at suspend time (and the connection is broken each time, of course). It keeps its minor if it isn't opened at suspend time. Otherwise the device works well with both minors. The issue is reproducible by

cd /sys/power
echo devices >pm_test
echo mem >state </dev/ttyUSB0
Comment 1 Zhang Rui 2012-01-18 02:03:07 UTC 
It's great that kernel bugzilla is back.

can you please verify if the problem still exists in the latest upstream
kernel?
Comment 2 Ferenc Wágner 2012-01-22 23:20:13 UTC 
Yes, the issue is present under 3.2. However, now I think it basically comes down to missing suspend/resume support in the ark3116 driver: the USB core has no choice besides unbinding the driver for the suspend period. If so, this is more a feature request than a bug report...
Comment 3 Zhang Rui 2012-05-24 07:31:38 UTC 
re-assign to the USB experts.