On 14/03/16 17:19, Gregor Boirie wrote: > On 03/09/2016 09:46 PM, Jonathan Cameron wrote: > > [snip...] >> Definitely needs ABI docs in Documentation/ABI/testing/sysfs-bus-iio >> as well. We need the reference directions to be well specified as >> well - how do we define the main hardware orientation? on yours presumably >> the usual approach of using the screen is irrelevant so that definition >> could be a little 'interesting' to write down? >>> The standard orientation for us is defined with respect to the drone's head >>> and the propellers plane, which does not suit the nominal use cases indeed... >>> Although it really deserves some more detailed documentation, I wonder if the >>> question is relevant. >>> Given that the DTS is board specific (correct me if I'm wrong), why not >>> consider the reference orientation as board specific as well (and make the >>> whole thing implicit) ? >> I think that is fine for your sort of usecase - though might be nice to keep >> a bit of documentation somewhere (perhaps as comments in the DTS), or perhaps >> more centrally - would be nice for userspace libraries if at least all aircraft >> had a similar 'default orientation'. > As you said earlier, things are never that simple. The standard orientation > may vary with types of UAVs (quad-rotor, fixed wings, bizarre home made UFOs...) Sure, but let's document what we can so at least some cases are covered >> For the more 'standard' device with a screen I think we would want to standardise >> if at all possible. Most hand held devices have a 'natural' orientation >> (front facing camera at the top for example). In those cases we are basically looking >> at whether the sensor is mounted on the back or the front of the main circuit board and >> then of course it can be at any rotation in plane but typically is at 90 degrees >> (hence the inv mpu limitations) >> >> I'm guessing there are existing userspace mappings for this. Perhaps in the Gnome >> sensors stuff? > [snip...] > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
