Cinterion plugin - unsupported ^SIND="simstatus"

[Colin Helliwell]

> On 01 January 2018 at 11:27 Colin Helliwell wrote:
> 
> 
> > On 01 January 2018 at 10:48 Aleksander Morgado wrote:
> > 
> > 
> > On Sat, Dec 30, 2017 at 4:30 PM, Colin Helliwell
> >  wrote:
> > >
> > >> On 30 December 2017 at 15:07 Colin Helliwell wrote:
> > >>
> > >>
> > >> The Cinterion plugin tries 'AT^SIND="simstatus",2' in after_sim_unlock(). I have two Cinterion modems, neither of which - according to their AT Command Set spec - support the simstatus indicator on this command, and so instead return "+CME ERROR: 21" (invalid index).
> > >> Nonetheless, the operation continues with all 15 of its retries. Should there perhaps be a 'if (!response)' trap in simstatus_check_ready() so that it bombs out?
> > >> I ask for comment, since I'm not sure (a) exactly what the retries are waiting for; and, in particular (b) what the response would be while its waiting. (I don't have a modem which does support the indicator).
> > >>
> > >
> > > I imagine not even getting a good response can be treated as unsupported, let alone needing to parse it for ^SIND content . Hence
> > > 
> > > 
> > >  plugins/cinterion/mm-broadband-modem-cinterion.c | 99 ++++++++++++++++++++----
> > >  1 file changed, 6 insertions(+), 1 deletions(-)
> > > 
> > > diff --git a/plugins/cinterion/mm-broadband-modem-cinterion.c b/plugins/cinterion/mm-broadband-modem-cinterion.c
> > > index 64c5e08..1034d5c 100644
> > > --- a/plugins/cinterion/mm-broadband-modem-cinterion.c
> > > +++ b/plugins/cinterion/mm-broadband-modem-cinterion.c
> > > @@ -1590,7 +1629,12 @@ simstatus_check_ready (MMBaseModem *self,
> > >  const gchar *response;
> > > 
> > >  response = mm_base_modem_at_command_finish (self, res, NULL);
> > > 
> > > 
> > > * if (response) {
> > > 
> > > 
> > > + if (!response) {
> > > + /* "simstatus" not supported, go on anyway */
> > > + g_task_return_boolean (task, TRUE);
> > > + g_object_unref (task);
> > > + return;
> > > + } else {
> > >  gchar *descr = NULL;
> > >  guint val = 0;
> > Does the modem support AT^SIND at all? Or just the "simstatus"
> > indication isn't supported in the command?
> 
> Just that simstatus isn't supported
> > As with other things, the best way to maintain this upstream is to try
> > to query first for the support of the specific feature and, if
> > unsupported, ignore it from then on. In this case the support checks
> > would be for either the whole command (e.g. AT^SIND=?) or for the
> > actual "simstatus" indication (e.g. looking for "simstatus" in
> > AT^SIND=? if that makes sense).
> 

I would though put a case that: this command is only used in the Cinterion plugin, and no later knowledge of its outcome is currently needed - it seems to be just a 'pause step' in a sequence of other operations. 'psinfo' is also looked for elsewhwere, but again a fairly simple known/not-known operation.
So your suggestion, whilst for sure its strictly correct and best, could perhaps be - at this time, at least - an unnecessary complication/overhead...?
Respectfully yours etc :)