On 4 June 2014 17:55, Mark Brown <broonie@xxxxxxxxxx> wrote: > On Tue, Jun 03, 2014 at 12:57:52PM +0200, Ulf Hansson wrote: >> On 28 May 2014 13:03, Mark Brown <broonie@xxxxxxxxxx> wrote: > >> > No, runtime PM isn't really fine grained - I'm talking about things >> > like starting and stopping individual resources or configuring them. > >> Are you saying that you have several levels of quiescent mode of your >> external chip? > > Partly, but also there can be active modes that don't use all > functionality and hence can leave some of the inputs powered down (for > example if a reference clock is used for some feature that isn't used > all the time then that reference clock may be able to be powered down > when the function is not in use). The device isn't suspended but it can > do without some of the resources it has. > >> I am a bit puzzled of how such library should look like, but I suppose >> we need to be able to go to different power states through it. >> Typically the library may be invoked both from the mmc core to do >> power up/off and from the sdio func driver to handle power save. > >> Does it make sense to you as well? > > Yes, certainly for the power up/down and runtime PM type operations. For your information; I have started implementing a library to handle power sequences. I intend to have this separated from mmc, to let other subsystems re-use the same code. It will not require a compatible string, but instead use something like 'power-method = blah' property. I intend to post this as an RFC in couple of days. Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
