On Wed, Oct 31, 2012 at 4:05 AM, Daniel Mack [off-list ref] wrote:

On 30.10.2012 21:01, Vasily Khoruzhick wrote:

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On Mon, Oct 29, 2012 at 2:14 PM, Daniel Mack [off-list ref] wrote:

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On 29.10.2012 12:12, Vasily Khoruzhick wrote:

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On Mon, Oct 29, 2012 at 2:00 PM, Daniel Mack [off-list ref] wrote:

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Well, there's an issue - Z2 does not preserve memory contents in

deep sleep

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(but it does in sleep), so userspace can't be fixed here

unfortunatelly.

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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

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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

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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?

Haojian was working on the PXA pinctrl drivers, but I don't know how far
that is yet.

If that's not yet there, have a look at the pinctrl-single driver. It's
admittedly not as nice to use as the constants in the board file as DT
lacks defines for numerical constants, but's at least a workaround.

On a more general note, it's arguable whether this kind of setup should
be done in the bootloader after all.


Daniel

Using pinctrl-single driver is preferred. I'm converting mmp pinctrl driver
into pinctrl-single
driver. I'll submit a new round in these days.

Thanks
Haojian
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