[PATCH 2/5] ARM: PXA: Zipit Z2: Add USB host and device support

[Vasily Khoruzhick]

On Mon, Oct 29, 2012 at 2:14 PM, Daniel Mack <zonque at gmail.com> wrote:
> On 29.10.2012 12:12, Vasily Khoruzhick wrote:
>> On Mon, Oct 29, 2012 at 2:00 PM, Daniel Mack <zonque at gmail.com> wrote:
>>
>>>> Well, there's an issue - Z2 does not preserve memory contents in deep sleep
>>>> (but it does in sleep), so userspace can't be fixed here unfortunatelly.
>>>> There's no another possibility to turn Z2 off, and plain sleep is too
>>>> power hungry.
>>>> So the only way to keep Z2 in low-power mode is fake power off, which just puts
>>>> Z2 in deep sleep.
>>>
>>> Why can't the userspace trigger a deep sleep then instead of powering
>>> off? Which details do I lack?
>>
>> How? echo mem >/sys/power/state puts system into non-deep sleep. Anyway, kernel
>> is not ready for fake power off instead of suspend (we can't resume
>> from deep sleep,
>> memory content is not preserved), so there can be some data loss.
>> Adding some sysfs file to control sleep type does not look like a good
>> idea to me.
>>
>> Btw, how other DT-capable boards handle power off?
>
> No idea. I never actually used that kind of power state.

Hi Daniel,

One more question: what should I use instead of pxa2xx_mfp_config in
DT board to configure pin modes?

Regards
Vasily