Hi, On Mon, Nov 30, 2015 at 03:51:56PM -0800, Kevin Hilman wrote: > Alexander Aring <alex.aring@xxxxxxxxx> writes: > > > This patch adds support for RPi several Power Domains and enable support > > to enable the USB Power Domain when it's not enabled before. > > > > This patch based on Eric Anholt's patch to support Power Domains. He had > > an issue about -EPROBE_DEFER inside the power domain subsystem, this > > issue was solved by commit <311fa6a> ("PM / Domains: Return -EPROBE_DEFER > > if we fail to init or turn-on domain"). > > [...] > > > +#define RPI_POWER_DOMAIN(_domain, _name) \ > > + [_domain] = { \ > > Using _domain as the array index is going to create a sparsely filled > array here, wasting memory. I'm not sure what the other domain numbers > are for other domains to know if this is a big waste or not, but it's > still a bit wasteful. > > In any case, AFAICT, it doesn't look like you need to have the array > index match the domain number anyways since you're using container_of(). > > So I suggest just removing this array index part, and just creating them > in arrary order. Then your _probe function isn't going to try to setup > 3 non-enabled domains before it finally hits the USB domain. > The idea is here to keeping the _same_ power domains indexes for device-tree power domain API like the RPi firmware provides it. If somebody dumps the devicetree and see the power domain index, if he/she does then a firmware API power domain index mapping it is wrong. Because we need then a separate mapping: $ARRAY_DEFINED_INDEX <-> $RPI_FIRMWARE_POWER_DOMAIN_API_INDEX With the current solution to make a 1:1 mapping it there is no confusing anymore, because: $ARRAY_DEFINED_INDEX == $RPI_FIRMWARE_POWER_DOMAIN_API_INDEX Also there exists power domains 1-10 (so far I know), 1-2 are currently not used (and dummy-calls inside the rpi firmware implementation). So later they should be provided anyway. There exists a little improvement to let the for (i = 0; i < num_domains ...) start at "i = 1", the entry with index "0" will be a waste of memory then and it's not provided by the firmware API as a power domain. These are my arguments to keeping the current way of registering power domains, if you still want that I should change it then I will do it or maybe I show here some "good" arguments here to keeping this behaviour. Please let me know. Thanks. - Alex -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html