[Gta04-owner] Modem off

[Dr. H. Nikolaus Schaller]

Am 05.11.2013 um 15:02 schrieb Andreas Kemnade:

> Hi,
> 
> On Tue, 5 Nov 2013 08:51:26 +0100
> Radek Polak <psonek2 at seznam.cz> wrote:
> 
>> On Monday, November 04, 2013 11:09:27 PM Andreas Kemnade wrote:
>>> Hi,
>>> 
>>> On Sat, 2013-09-21 at 08:19 +1000, NeilBrown wrote:
>>>> I've experimented with "rmmod ehci_hcd" just before suspend, and
>>>> "modprobe" on resume, but so far that has just caused a mess.
>>>> I've looked at the code, and it is rather complex.
>>>> It has also changed a lot in 3.10.  So I'm going to defer exploring this
>>>> more until I start on 3.10+ again, probably in a couple of weeks.
>>> 
>>> In 3.12 I get also around 15mA more current in suspend with modem off.
>>> than with modem on. (suspend does not work reliable with that kernel for
>>> me and I have 60mA/85mA current consumption)
>>> 
>>> In 3.7 with enabled modem
>>> doing "echo ehci-omap.0 >unbind" in
>>> /sys/bus/platform/drivers/ehci-omap
>>> also increases current. (I get 40mA then)
>>> doing "echo echi-omap.0 >bind"
>>> decreases it again to around 20mA.
>>> That is also strange.
>>> 
> btw: what is different in doing rmmod/modprobe and doing the unbind/bind?
> 
>>> Hmm, what a about doing modprobe/rmmod in
>>> modem-poweron.sh/modem-poweroff.sh?
>> 
>> What would it be good for?
>> 
>> I think Neil's idea was to rmmof USB in sleep. Incoming call modem wakes the 
>> devices up via interrupt, we load the USB driver and using CLCC we detect who 
>> is calling etc... I havent tried myself, but this seems doable. In qtmoko you 
>> can add "rmmod ehci_hcd" to before-suspend.sh and modprobe to after-resume.sh 
>> scripts to implement it.
>> 
> 
> Hmm, the problem was the suspend current is higher when the modem is off. 
> And then Neil found out that removing ehci-hcd reduces that. So if rmmod ehci-hcd
> reduces suspend current when modem is off, then do the rmmod when the modem is turned off
> (so it is also not present when the device is suspended with modem off)

Yes, I remember that not the modem is drawing power (I had measured that long time ago)
but the EHCI module on the OMAP3 and/or the USB332 PHY chip is not properly powered down.

I.e. the modem is behaving ok.

-- hns