On Tue, May 1, 2012 at 3:21 AM, Kevin Hilman <khilman@xxxxxx> wrote: > Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx> writes: > >> On Fri, Apr 27, 2012 at 02:01:17PM -0700, Kevin Hilman wrote: >>> Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx> writes: >> >>> > But presumably these things should integrate somehow - for example, >>> > should devfreq and cpufreq be providing inputs into what AVS is doing, >>> > and if so how? >> >>> The way it is currently designed, cpufreq/devfreq/regulator layers don't >>> need to know about AVS. >> >> Yes, and that was a part of my concern, but see below. >> >>> The higher-level layers only know about the "nominal" voltage. AVS >>> hardware does automatic, adaptive, micro-adjustments around that nominal >>> voltage, and these micro-adjustments are managed by the AVS hardware >>> sending commands to the PMIC. (specifically, on OMAP, the AVS sensors >>> provide inputs to the voltage processor (VP) which provide inputs to the >>> voltage controller (VC) which sends commands to the PMIC[1].) >> >> Right, that's what I'd understood it to be. >> >>> The driver proposed here is primarily for initializing the various >>> parameters/sensitivity/etc. of the AVS hardware, but the actual voltage >>> adjustments are done in hardware by VC/VP. >> >> It's not just a driver, though - it's also creating this power/avs >> thing, though now I look at the code rather than just its shape there's >> not actually an abstraction being added here, it's mostly just straight >> code motion of the arch/arm code that's there already. The changelog >> and the shape of the code make it sound like this is intended to be >> somewhat generic when really it's providing some OMAP specific tuning >> for the device which is much less of a concern. >> >> I guess for now it's probably OK to just clarify in the documentation >> and say that whoever adds the second driver has to work on making this >> generic :) > > Agreed. > > In a different thread (which I can't seem to find now) we discussed this > as well, so it just sounds like the changelog should clarify this a bit > better. Kevin/Mark, Thanks for the feedback. I will add more documentation to clarify this aspect. Please let me know if there are any more things to be taken care of in this patch set. > > Kevin > >> This does also sound rather like it's in a similar area to the current >> management work which Durgadoss R (CCed) was working on, though with a >> slightly different application and in the OMAP case it's pretty much all >> hidden in the external processor. > -- Regards and Thanks, Keerthy _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/linux-pm
