On Sun, 31 Aug 2008, Elias Oltmanns wrote: > Admittedly, I don't know very much about it myself but I seem to > remember that there are other vendors now shipping similar technology. Apple, HP. > Even in the Thinkpad case I don't *know* that all relevant models have > HD and optical drives on seperate ports although I'm willing to believe > it if somebody tells me so. All the models I know of have them on separate ports/channels. > Anyway, I've added Henrique to the Cc: list since he knows far more > about Thinkpads than I do and possibly about other notebooks too. I know Apple does it, and they need exactly the same queue freeze + ATA unload immediate to have APS working. But they will want both a kernel interface (just using the firmware) and the userspace interface (to use something better than whatever is in Apple's firmware). > There is a lot to be said for the per-port solution as far as libata is > concerned. For the sake of consistency I tried to mimic the same > behaviour in ide but I agree that it makes things more complex there. Frankly? I doubt anybody really cares about the old ide driver for this particular functionality. How many systems have an accelerometer, are portable enough to need APS, and have a SATA or PATA bridge that is not better driven by libata instead of ide? > > Which also brings again the question whether it is really the best to > > use user-space solution instead of kernel thread? Choice is good here. A really good imminent-shock predictor needs to do some fairly decent ammount of digital signal processing (in 2d or 3d, depending on the sensor). That stuff is a lot easier to do if you have floating point math available to you, for example. That means userspace. And some firmware can tell you "please do APS NOW!", so, for those you want a kernel interface. -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
