>Hi, > >> I am newbee to this mailing list. Please excuse me if I am talking nonsense here. >> >> >> >> On Thu, Jul 9, 2009 at 10:48 PM, Alan Stern<stern@xxxxxxxxxxxxxxxxxxx> wrote: >>>> On Thu, 9 Jul 2009, Magnus Damm wrote: >>>> >>>> Clocks should be stopped as soon as possible without any delay. The >>>> clock stopping is very cheap performance wise. Also, the clock >>>> stopping is done on bus level without invoking any driver callbacks. >>>>> Delaying the clock stopping does not make any sense to me. >>>> >>>> In that case the device driver or bus subsystem should manage the >>>> device's clock directly. There's no need to tie it in with the runtime >>>> PM framework. Simply start the clock before each I/O operation and >>>> stop it afterward. >> >>> It's not that easy. The clock needs to be enabled to let the hardware >>> device perform device specific stuff. For instance, the clock for the >>> LCD controller needs to be on to redraw the screen. When the driver >>> knows that it's done with the clock it can notify the bus using >>> Runtime PM. >> >> Is there any plan to look into the "Clock Framework" that was developed as >> part of OMAP and extending this to make it generic for all platforms? >I don't have any plan to do that and I heaven't heard of anyone planning to do >it. Thanks for the reply Rafael. I felt if we are talking about controlling a device clock from a runtime PM framework we should look at extending the Clock framework rather than re-inventing things. Regards, Nithish Mahalingam -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
