Huawei mode changing updated

[Dan Williams]

On Mon, 2013-11-11 at 12:04 -0600, Dan Williams wrote:
> On Mon, 2013-11-11 at 17:01 +0100, Aleksander Morgado wrote:
> > Hey,
> > 
> > I spent some time these past weeks implementing allowed/preferred mode
> > changing for the new ^SYSCFGEX-capable Huawei devices [1]. This new
> > ^SYSCFGEX command is an extension of ^SYSCFG thought for LTE devices
> > (like the ME906E) but is also now available in non-LTE devices (like the
> > MU736). Note that I only implemented mode changing, *not* explicit
> > frequency band changing.
> > 
> > While developing the support for ^SYSCFGEX, I also ended up developing
> > supported mode checks with AT^SYSCFG=? and AT^PREFMODE=?, instead of
> > blindly relying that these are supported.
> > 
> > I've tested the new ^SYSCFGEX support both with a ME906E and a MU736[2],
> > and ^SYSCFG support with a E220, but *haven't* tested with AT^PREFMODE
> > as I don't have a CDMA Huawei modem around.
> > 
> > This new development is available in the 'aleksander/huawei-modes'
> > branch upstream. Further tests and comments are very welcome :)
> 
> Tested the prefmode support, pushed a small fixup.  That part looks
> fine.  I'll have to check the SYSCFG/SYSCFGEX a bit later.

Tested with a bunch of devices today.  I pushed another fixup to the
branch.  Oddly, not just the E220 responds to SYSCFG=? with just "OK",
my K3520 also does.  But the defaults work fine there.

One issue I had was:

[mm-at-serial-port.c:436] debug_log(): (ttyUSB2): --> 'AT^PREFMODE?<CR>'
[mm-at-serial-port.c:436] debug_log(): (ttyUSB2): <-- '<CR><LF>^MODE:
0<CR><CR><LF><CR><CR><LF>^RSSILVL:0<CR><CR><LF><CR><CR><LF>^HRSSILVL:0<CR><LF>'
[mm-at-serial-port.c:436] debug_log(): (ttyUSB2): <--
'<CR><LF>^PREFMODE: 2<CR><LF><CR><LF>OK<CR><LF>'
[mm-iface-modem.c:2416] after_set_load_current_modes_ready(): couldn't
load current allowed/preferred modes: 'Unexpected PREFMODE response:
'^RSSILVL:0

^PREFMODE: 2''

for the EC168C, likely because the RSSILVL regex doesn't get enabled
until the modem gets enabled, but you can still change allowed/preferred
modes before that.  This isn't a blocker though, and can be fixed later.

So take a look at my fixups and if you think they're OK, squash and
merge to master?

Cheers,
Dan