Tomi Valkeinen <tomi.valkeinen@xxxxxxxxx> writes: > Hi, > > On Fri, 2009-09-18 at 19:33 +0200, ext Mike Chan wrote: >> On Fri, Sep 18, 2009 at 1:27 AM, Tomi Valkeinen >> <tomi.valkeinen@xxxxxxxxx> wrote: >> > Hi, >> > >> > If you disable the clocks to allow RET, you also allow OFF mode. And >> > resuming from OFF mode hasn't been implemented for DSI, if I recall >> > right. And when I was testing it, it didn't seem to be trivial with the >> > DSI PLL. >> > >> >> You can limiting the pwrdm next state to RET when being called from cpuidle. > > No, you _must_ limit it to RET. Otherwise the DSI will break down. So we > can either keep the dsi code as it is now, or explicitely disable OFF > mode and then apply your patch. But your patch alone won't work. Or could add a hack to this patch so that 'enable_off_mode' doesn't affect DSS_MOD until DSS has off-mode support. > In the long run I think we anyway need to somehow dynamically manage the > power state. I haven't measured it but I believe resuming from OFF will > have a bit of a penalty, as (I think) DSI PLL etc. will have to > reinitialized. But it would still be good to allow RET whenever > possible, and OFF only after some period of inactivity. This is the purpose of latency constraints. These can be used when the latency of going OFF will cause a problem. Kevin -- 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
