#10169 NORM Not Tri: inhibit suspend if USB devices are connected / in use

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#10169: inhibit suspend if USB devices are connected / in use
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 Reporter:  sascha_silbe            |                 Owner:  pgf                               
     Type:  defect                  |                Status:  new                               
 Priority:  normal                  |             Milestone:  Not Triaged                       
Component:  power manager (powerd)  |               Version:  Development source as of this date
 Keywords:                          |           Next_action:  code                              
 Verified:  0                       |   Deployment_affected:                                    
Blockedby:                          |              Blocking:                                    
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 Since the USB ports are powered down during suspend on XO-1[.5], powerd
 should inhibit suspend if any USB device is in use. A lot of devices
 (personal experience) don't cope well with power cycles. This is
 especially bad for USB sticks that are in active use (working directory,
 open files, ...) across suspends as Linux doesn't cope well with devices
 backing mounted filesystems disappearing at run-time.

 One approach would be to inhibit suspend if devices of a certain USB
 devices class (CDC ethernet, HID, ...) are plugged in (blacklist) or if
 any device is plugged in that has at least one interface not belonging to
 a certain set of USB device classes (whitelist).

 Another approach would be to patch the kernel to provide information about
 whether a device is "in use" (already tracked for USB autosuspend, but not
 available to userspace) and inhibit suspend if any USB device is in use.
 This would allow suspending if e.g. the network interface has been
 explicitly disabled by the user (by using NetworkManager from within
 Gnome?), but obviously requires more effort to implement.

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Ticket URL: <http://dev.laptop.org/ticket/10169>
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