On 29.10.2012 11:52, Vasily Khoruzhick wrote:

On Mon, Oct 29, 2012 at 1:44 PM, Daniel Mack [off-list ref] wrote:

quoted

I haven't seen any patches for DT bindings of this yet.

quoted

I still don't understand how DT handles platform-specific
callbacks like set_power(). And what about pm_power_off hook?

They require consideration.

In general, a driver should be aware of everything that affects the
peripheral, including all the voltages and clocks it needs and also all
extra pins like for example reset GPIOs etc. And all that properties are
to be exported via DT as well (things that you would have normally set
up using pdata).

If drivers lack that kind of full awareness of their environment, they
need to be augmented, because - to stick with the example of reset GPIOs
- the driver of all parts is the only piece that knows when to driver
that pin and how.

About the hack to put the z2 to deep-sleep when it should actually power
down, I don't know what to do. But I would say that it's the userspace
that should be fixed here, if possible.

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?