On Mon, 14 Apr 2008, Nigel Cunningham wrote: > > The ability for prepare() callbacks to sync with userland, > > request_firmware, etc... is an important feature that's been needed for > > some time imho. > > > > Ben. > > I agree. These calls have already been changing far too often in > mainline. I know it's all been necessary but please, can we try to make > one set of changes and just get it right this time? In practical terms, it will be easier to keep the freezer where it is for now. This is because prepare() requires drivers to change their behavior; they aren't allowed to register new children any more. But if userspace isn't frozen then user programs can interact with drivers in a way that does cause new children to be created. For example this happens in USB, where opening an audio device and selecting its bitrate causes a new set of endpoints to be realized, along with their representations in sysfs. Thus, in addition to making all the interface changes implied by the new callbacks, drivers would also have to change the way they interact with userspace. Yes, this will have to be done eventually in any case, as the freezer goes away -- but it shouldn't have to be done right now. Alan Stern -- 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
