On Fri, Jul 1, 2011 at 3:04 PM, Paul Walmsley <paul@xxxxxxxxx> wrote: > cc'ing Kishon > > On Fri, 1 Jul 2011, Cousson, Benoit wrote: > >> On 7/1/2011 11:23 AM, Paul Walmsley wrote: >> > On Fri, 1 Jul 2011, Jarkko Nikula wrote: >> > >> > > Active sidetone requires that McBSP interface clock doesn't idle and there >> > > is no mechanism in hwmod to turn autoidling on/off in runtime. McBSP2 and >> > > 3 >> > > in OMAP34xx share their interface clock with McBSP sidetone module and >> > > that interface clock must be active when the sidetone is operating. >> > > >> > > Sidetone has its own autoidle bit which should keep the interface clock >> > > active but it is broken. Putting the McBSP core to no-idle mode when the >> > > sidetone is active is no good either since it results to higher power >> > > consumption when using the threshold based DMA transfers. >> > >> > In the hwmod code/data, we've got the OCPIF_SWSUP_IDLE flag that can be >> > set on a struct omap_hwmod_ocp_if. I think this is probably what's needed >> > here. The only problem is that we haven't linked that to the clock code >> > to deny idle on the interface clock yet (see omap_hwmod.c:_setup()). >> > Adding that code in, plus adding that OCPIF_SWSUP_IDLE flag to the >> > McBSP2/3 data, seems like the right approach here. >> > >> > I guess we also will need some basic usecounting for denying idle in the >> > clock code. >> > >> > Otherwise these direct register manipulations of clock registers, outside >> > the clock code, could turn into a mess :-( >> >> AFAIR Kishon did submit some patches to expose this feature to the driver >> through omap_device API. The point is that other broken IP like SDMA of USB >> will require such feature. >> >> Didn't we pull them? I'll repost by early next week. > > You sent him some comments on March 1 but it looks like the series never > got updated and reposted, at least not that I can find in my mail > archive. Kishon? > > Anyway, those patches won't help in this case if the sidetone AUTOIDLE bit > is broken - looks like the interface clock autoidle bit is what needs to > change. > > > - Paul > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
