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

[Aleksander Morgado <aleksander lanedo com>]

> Power Up = enabled
> Power Down = disabled
> 
> So we already have those states in ModemManager via the Enable() method
> and the modem states.  It's just that not all devices actually implement
> the low-power mode when disabling, partially because we're not always
> sure of the side-effects.
> 

The problem here isn't that we don't have a safe power-down command; the
problem is that even if we have it, we don't use it just after plugging
in the modem:
  initialized -> locked -> disabled

But for that 'disabled' state we didn't run the power-down command even
if we have it, so the radio interface may be powered on there. That's
the thing to fix by running the disabling sequence just after
initialization. If there is no default power down command, then we would
run the disabling sequence but without any power down command, so no big
deal.

-- 
Aleksander