Re: [MM] Power down during init (was: Re: [MM master] Re: [MM06] [PATCH] sierra: use +CFUN=4 for powering down)

[Marius Kotsbak <marius kotsbak gmail com>]

2012/9/18 Marius Kotsbak <marius kotsbak gmail com>

2012/9/18 Aleksander Morgado <aleksander lanedo com>

Hey Dan and Marius,

>
>> 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.
>

The attached patch runs just a new power-down step during the modem
initialization, to ensure it starts in low power mode. Adding a new step
to run power-down instead of running the whole disabling sequence seemed
a better option, as the disabling sequence really assumes we were
previously enabled. Note that this patch just re-uses the power-down
implementation given in each plugin, which we previously used only
during the disabling sequence.

Given that it's quite a big change, can you guys try it with some of the
modems that we know have given issues before with these things? Thinking
on Sierra modems specifically here. I've got a Wavecom modem which also
had issues with CFUN (e.g. rebooting on CFUN=1 if it was already in
CFUN=1), but won't be able to test it until Friday.

Tested my ZTE MF820D and seems to work nice.

But it seems not to work with my Sierra modem in AT mode:

ModemManager[3734]: <debug> [1347998708.810662] [mm-serial-port.c:929] mm_serial_port_open(): (ttyUSB3) device open count is 4 (open)
ModemManager[3734]: <debug> [1347998708.810953] [mm-at-serial-port.c:392] debug_log(): (ttyUSB3): --> 'ATE0<CR>'
ModemManager[3734]: <debug> [1347998708.815802] [mm-at-serial-port.c:392] debug_log(): (ttyUSB3): <-- 'ATE'
ModemManager[3734]: <debug> [1347998708.822968] [mm-at-serial-port.c:392] debug_log(): (ttyUSB3): <-- '0<CR>'
ModemManager[3734]: <debug> [1347998708.824151] [mm-at-serial-port.c:392] debug_log(): (ttyUSB3): <-- '<CR><LF>OK<CR><LF>'
ModemManager[3734]: <debug> [1347998708.824446] [mm-serial-port.c:969] mm_serial_port_close(): (ttyUSB3) device open count is 3 (close)
ModemManager[3734]: <debug> [1347998708.824688] [mm-at-serial-port.c:392] debug_log(): (ttyUSB3): --> 'AT+CMEE=1<CR>'
ModemManager[3734]: <debug> [1347998708.840464] [mm-at-serial-port.c:392] debug_log(): (ttyUSB3): <-- '<CR><LF>OK<CR><LF>'
ModemManager[3734]: <debug> [1347998708.840817] [mm-serial-port.c:969] mm_serial_port_close(): (ttyUSB3) device open count is 2 (close)
ModemManager[3734]: <debug> [1347998708.841066] [mm-at-serial-port.c:392] debug_log(): (ttyUSB3): --> 'AT!pcstate=0<CR>'
ModemManager[3734]: <debug> [1347998708.865357] [mm-at-serial-port.c:392] debug_log(): (ttyUSB3): <-- '<CR><LF>ERROR<CR><LF>'
ModemManager[3734]: <debug> [1347998708.865590] [mm-serial-parsers.c:316] mm_serial_parser_v1_parse(): Got failure code 100: Unknown error
ModemManager[3734]: <debug> [1347998708.865743] [mm-iface-modem.c:3025] initialization_modem_power_down_ready(): Modem initially powered down...

This might be caused by the check if it is CDMA or GSM modem is run before it knows the answer (see my patch I send in a moment).

--
Marius