[Sugar-devel] Patch: Mobile dongles

[Jerry Vonau]

On Mon, 2012-03-26 at 13:27 -0400, Paul Fox wrote:
> jerry wrote:
>  > On Mon, 2012-03-26 at 11:54 -0400, Paul Fox wrote:
>  > > jerry wrote:
>  > >  > On Mon, 2012-03-26 at 16:44 +1100, forster at ozonline.com.au wrote:
>  > >  > > David
>  > >  > > 
>  > >  > > This message was sent with a gsm dongle on an xo-1
>  > >  > >  
>  > >  > >  modem:Huawei E160E
>  > >  > >  carrier:Locked to Dodo (an Optus reseller)
>  > >  > >  XO-1
>  > >  > >  OS31 development which is same as os884 signed
>  > >  > >  
>  > >  > >  in my settings, enter username, password, leave *99# unaltered, dodolns1, blank, blank
>  > >  > >  
>  > >  > >  turn off power management, because XO looses connection in sleep mode
>  > >  > 
>  > >  > I have an enhancements to powerd to inhibit suspend for that issue. The
>  > >  > attached proof of concept patch is heavy on tracing, should apply, maybe
>  > >  > with an offset, and needs /etc/powerd/flags/modules-inhibits created
>  > >  > containing usb_wwan. Once usb_wwan is inserted in the kernel, it remains
>  > >  > in memory you can have NM dispatcher or pppd remove the module when the
>  > >  > connection is torn down to restore normal power management operation.
>  > >  > These features are in testable with au210. Sorry 4g images only, with no
>  > >  > firmware in the image. http://build.laptop.org.au/xo/os/latest/
>  > > 
>  > > is presence of the module really the best way to do this?  is it
>  > > possible to look for the presence of the network interface, or maybe
>  > > simply network traffic, or something similar?  
>  > 
>  > In the field test reports are saying the modem is getting reset upon
>  > suspend while the trying to connect. Think the 15 second, 5 second if
>  > your in suspend and don't have any other user activity, sleep loop may
>  > not allow enough time to have the modem complete the pppd handshake and
>  > bring up the interface. 
> 
> who manages the connection?  network manager?  

NetworkManager/modem-manager

> does it announce the connection sequence via dbus?  

They should but I'm unsure or what signals are. 

> powerd-dbus is already listening for
> connection status to prevent sleep during wifi association -- perhaps
> that mechanism can be leveraged.
> 

That would be the best way.

>  > 
>  > > i assume using the
>  > > existing usb-inhibits is impractical because of the variety of
>  > > devices, is that right?
>  > >   
>  > Yes, that is the reason. We want a one-size-fits-all fix where the user
>  > doesn't have to populate any files. 
>  > 
>  > > i guess it would be too much to ask for all
>  > > GSM devices to be in the same USB class.  :-/
>  > > 
>  > What would be the appropriate USB class? Mine comes up as usb-storage at
>  > first and usb_modeswitch has to act on it adding time to the connection
>  > routine. 
>  > 
>  > > (maybe the module presence check is okay -- it just doesn't feel right.)
>  > > 
>  > I think this could be used for other devices also like wedo or usb2vga
>  > maybe.
> 
> perhaps.
> 
> wedo is readily identifiable by vendor, i think -- and why would one
> want it to inhibit suspend?  that seems more like it should be under
> the activity's control.
> 

Think there needs to be a consensus on what should be in powerd and
which activities need to prevent suspend.

> i'd think (but don't know) that usb2vga would be used seldom enough
> that you could either inhibit suspend manually, or change the config
> so it doesn't suspend when plugged in -- i can't imagine using usb2vga
> when you don't have plenty of power available.

Sure untick the box in the applet is a good workaround, like for a usb
modem. ;)

Jerry