Re: [MM master] Re: [MM06] [PATCH] sierra: use +CFUN=4 for powering down

[Marius Kotsbak <marius kotsbak gmail com>]

Den 10. sep. 2012 11:56, skrev Aleksander Morgado:
> > > > > > > See patch attached.
> > > > > > >
> > > > > > > sierra: use +CFUN=4 for powering down
> > > > > > >
> > > > > > >     plugins/mm-modem-sierra-gsm.c |   32
> > > > > > > ++++++++++++++++++++++++++++++++
> > > > > > >     1 file changed, 32 insertions(+)
> > > > > > This also needs to be intregrated in the master branch version.
> > > > > > Attached
> > > > > > is my attempt to do it, but it seems not to work. I see no effect of
> > > > > > disabling the modem with "mmcli -m X -d".
> > > > > See review below.
> > > > >
> > > > > > Also, it seems like the power down is not done before the modem enters
> > > > > > disabled state at startup of MM or after modem is inserted, so I
> > > > > > filed a
> > > > > > bug about that:
> > > > > >
> > > > > > https://bugzilla.gnome.org/show_bug.cgi?id=683681
> > > > > Yes, that's a known issue, see TODO in the source tree.
> > The text there is slightly incorrect. It does not help if the modem is
> > in low power mode when started (some might also be configured to be),
> > because at least in the Sierra plugin, it is waked up to CFUN=1 in the
> > init anyway. This could be avoided by accepting CFUN mode 4 and 7 as
> > well. But then it must be changed to mode 1 when connecting.
> >
> > I am not sure if all the init steps are possible in low power mode.
> CFUN=1 is sent when *enabling* the modem, not during init. All the init
> steps should really be possible while in CFUN=4 low power mode as that
> should only kill the radio power.

Sorry, I did not test it or dig deep enough in the code. If I sent the 
modem to CFUN=4, it actually keeps this state after the init, and 
enabling works fine.

> Also, for Sierra modems there's the problem that CFUN=1 may actually
> reboot the modem, so the problem with powering down the radio with
> CFUN=4 in Sierra is that this may require a reboot/reprobing of the
> modem afterwards :-/ IIRC Wavecom (which also suffers from the same
> issue) had a CFUN=1,0 to try to go into full functionality mode without
> rebooting, not sure if Sierra has something similar.

Seems my Sierra modem has the same:

+CFUN: (0-1,4-7),(0-1)

but the default is ",0" on my modem, as "CFUN=1,1" behaves just like 
"CFUN=1", but "CFUN=1,1" causes a restart.

We could do a detection of the right version by using some regex of the 
CFUN=? output.

--
Marius