On Fri, Jan 29, 2016 at 08:11:19PM +0800, menghui lin wrote:

On Fri, 2016-01-29 at 12:27 +0100, Mark Brown wrote:

quoted

None of this is answering my question - I know what the current API is,
describing it doesn't tell me about actual users or how they are able to
sensibly use the interface.  Bear in mind that the definitions of the
various modes are all relative and what one device thinks is high usage
may be low usage for another device.

Assuming valid_modes_mask and initial_mode are specified, a possible
way to modify regulator_set_mode() is to allow mode change only if the
regulator is controlled exclusively by a certain consumer or the
requested mode provides stronger power capability than current mode.
Here I assume that power capability fast > normal > idle > standby.

...and I also note that the above *still* doesn't answer my questions
above.