On Mon, 1 Apr 2019 10:52:45 -0700
Tony Lindgren <tony@atomide.com> wrote:

> Hi,
> 
> * Keerthy <j-keerthy@ti.com> [190322 17:16]:
> > +static int am43xx_check_off_mode_enable(void)
> > +{
> > +	/*
> > +	 * Check for am437x-sk-evm which due to HW design cannot support
> > +	 * this mode reliably.
> > +	 */
> > +	if (of_machine_is_compatible("ti,am437x-sk-evm") && enable_off_mode) {
> > +		pr_warn("WARNING: This platform does not support off-mode, entering DeepSleep suspend.\n");
> > +		return 0;
> > +	}
> > +
> > +	return enable_off_mode;
> > +}  
> 
> Considering off-mode suspend depends on how the board is
> wired for various things such as memory, PMIC and the related
> signal lines, I agree using the machine compatible is the best
> check we can do here.
> 
> But since the device can hang during suspend unless things are
> configured right for the board, I suggest you rather list allowed
> boards here that are known to work with off-mode.
> 
Could we somehow describe this property of the hardware
(is-offmode-capable or is-wired-for-offmode) as a separate devicetree
property of the soc?

In mmc we have for example "cap-power-off-card" for
indicating some is-wired-suitable-for thing.

That looks to be clearer as looking for some strange conditions
derived from something.

I have still my offmode patch os the boilerplate...

Regards,
Andreas