pm: add suspend_mem and suspend_standby support

[Jean-Christophe PLAGNIOL-VILLARD]

On 11:44 Tue 09 Oct     , Alan Stern wrote:
> On Tue, 9 Oct 2012, Jean-Christophe PLAGNIOL-VILLARD wrote:
> 
> > > Why do you need to know the difference in your driver?  We used to
> > > provide this information a long time ago, but it turned out to not be
> > > needed at all and just caused problems.
> > because on at91 I need to handle the mem standby at drviers level.
> > 
> > We do it today already by a hack in different drivers at91_udc (usb device),
> > atmel_serail and at91_ohci. Those 3 IP have specifci handling when switching
> > to mem pm. On at91 when switch to mem we shutdown everything and run form a slow
> > clock - this is done at soc level - but those IP have issue and need specific
> > care before doing so. Ohterwise when the SoC will wakeup but those IP will not
> > 
> > in this patch series I send the update of those 3 drivers too
> > and kill the hack
> 
> How about adding a platform-specific callback routine to tell drivers 
> whether or not they will run from the slow clock?  Something like:
> 
> 	bool at91_suspend_will_use_slow_clock(void);
> 
> That would not involve making any changes to the driver core, and your 
> three drivers could still get the information they need.
I already do so and I want to drop it as the IP is shared with multiple ARCH
and I want to have a clean code no hack

and no platform data I do DT and drop board code so far, I've a dt code
without any platform data provide via c code

Best Regards,
J.