On Wed, Nov 13, 2013 at 01:13:06PM -0700, Stephen Warren wrote: > On 11/13/2013 12:07 PM, Mark Brown wrote: > > This isn't really regulator specific - it's something that applies > > in general to things implementing deferred probing - so we ought to > > have a generic "we know if devices can appear later or not" flag > > that subsystems can check. > I guess I misunderstand then, since given that modules exist, wouldn't > that flag always be true? No, with DT you can say that if there is no DT binding configuring a given thing (clock, regulator, GPIO or whatever) then no amount of module loading will ever cause it to appear - this is what the flag in question controls. > IIUC, the issue being discussed here isn't about deferred probe at > all. You always must defer probe if an object is specified as existing > yet the provider isn't available yet. The issue here is when a > regulator isn't specified as existing, yet something asks for that > regulator, should the regulator subsystem automatically provide a > dummy regulator instead, rather than erroring out. No, it's a deferred probing thing - one of the effects here is that we're choosing between deferring waiting for the resource we know is bound to appear and substituting a dummy for something we know exists physically and we know can never be provided by software.