Re: [MM] [PATCH 2/3] ZTE: Use +CFUN=4 to turn off radios when disabling

[Aleksander Morgado <aleksander lanedo com>]

On 16/04/12 17:40, Alexander Orlov wrote:
> ZTE modem stays connected and consumes power when disabled. This patch
> uses +CFUN=4 command to turn off radio module. Command +CFUN=0 gains
> more power savings, but is more dangerous.
>
> --- a/plugins/mm-modem-zte.c	2012-03-13 23:06:11.000000000 +0400
> +++ b/plugins/mm-modem-zte.c	2012-04-15 15:16:47.124025688 +0400
> @@ -561,8 +561,10 @@
>           mm_modem_icera_change_unsolicited_messages (MM_MODEM_ICERA (modem), FALSE);
>       }
>
> -    /* Random command to ensure unsolicited message disable completes */
> -    mm_at_serial_port_queue_command (primary, "E0", 5, disable_unsolicited_done, info);
> +    /* Random command to ensure unsolicited message disable completes.
> +     * Try to power off the modem: +CFUN=0 gains more energy savings,
> +     * but +CFUN=4 is safer (just disables radio module) */
> +    mm_at_serial_port_queue_command (primary, "+CFUN=4", 5, disable_unsolicited_done, info);
>   }
>
>   /*****************************************************************************/
>
> > We do have a POWER_DOWN property for that. Are we sure that the
> > power-down command will not harm other ZTE modems around?
> I didn't understand how to use POWER_UP/DOWN properties. If someone
> helps me, I'll be glad to implement them.

See the way it's done for Wavecom:

http://cgit.freedesktop.org/ModemManager/ModemManager/tree/plugins/mm-modem-wavecom-gsm.c?h=MM_06#n212

In the ZTE plugin case, using POWER_UP as well may be not needed, as the 
plugin overrides the whole enabling sequence, and therefore the generic 
code launching the power up command from that property is never called 
(just check if there is a +CFUN=1 command sent alone in the logs). But 
for POWER_DOWN, it probably applies.

--
Aleksander