On Tue, Oct 20, 2009 at 4:41 AM, Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > On Tue, Oct 20, 2009 at 03:21:17AM -0500, Nelson Castillo wrote: > >> Can the s3c driver send the events at full speed? (Maximum possible ADC rate?). Yes, but in packets I think (The way I would know how to implement it). We could try sending 2000 events per second to user-space and see what happens :-) :-) >> Even if it's possible I think we would monopolize the adc driver >> needlessly because we don't need all that conversions when there is >> not much noise. Please read on. > > There's currently no facility to push sample rate requests down into the > kernel from userspace. However, this is a good idea in general - there > was some recent (brief) discussion of doing this on the linux-input list. I see. It makes sense. ATM one big difference with the kernel approach is that in the kernel you can request the adc conversions on demand. > Since different use cases have different sample rate requirements (such > as the difference between handwriting recognition which can need 200 > samples/second and a simple finger operated menu which may be happy with > 10) there's value in being able to vary the sample rate at run time. I > was intending to look at this shortly as part of some touchscreen driver > development I need to do soon or perhaps someone else will pick up the > idea, if it does get implemented then obviously tslib would also be able > to use it here. With a lot more points you can indeed do better filtering in users-pace. -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
