On Wed, Mar 16, 2016 at 12:09 PM, Clément VUCHENER <clement.vuchener@xxxxxxxxx> wrote: > 2016-03-16 16:26 GMT+01:00 David Herrmann <dh.herrmann@xxxxxxxxx>: >> Hi >> >> On Wed, Mar 16, 2016 at 4:10 PM, Bastien Nocera <hadess@xxxxxxxxxx> wrote: >>> On Tue, 2016-03-15 at 17:17 -0700, Roderick Colenbrander wrote: >>>> Hi Bastien, >>>> >>>> Thanks for providing this suggestion. I can see this approach work >>>> for >>>> situations like screen rotation on tablets. The device I'm involved >>>> with is an input device, which needs a high poll rate for >>>> acceleration >>>> / velocity and needs to be paired with the button / axes data. Evdev >>>> would be most appropriate. >>> >>> So more like a Wiimote than a builtin sensor. What will consume events >>> in user-space? A specialised application? >> >> I really think evdev is the right place to put any of those devices. >> The real problem is that the current set of ABS types is very limited >> and strongly overloaded. We didn't do this for other types, but >> somehow ABS turned out that way. >> >> In general, Dmitry was ok with introducing new ABS types, properly >> representing those types. I sent an RFC some years ago, which also >> introduces gyro and accelerometer types (see patch #4): >> >> https://lists.freedesktop.org/archives/input-tools/2013-December/000612.html >> >> The problem is, however, that the current ABS_* namespace is >> exhausted. That is, we have to introduce some new way to add new ABS >> types (the series introduced ABS2 for that). No-one continued that >> effort so far, so we are stuck with the current ABS types. Feel free >> to pick this up. It might be a lengthy effort, though. You might be >> better off doing it the wiimote way: pick you ABS types and make >> user-space recognize them depending on the device name/etc. > > Hi. > > I am writing a user-space driver for the steam controller and I was > wondering how that would fit. The steam controller reports its > absolute gyro data as a quaternion instead of three angles. Although, > in the case of the steam controller, this data is meant to emulate > other kind of devices from the driver, if applications started to use > such an interface, it would be nice that the steam controller supports > it. > >> >> Thanks >> David I haven't with the SteamController yet. Based on iFixit it has a 3-axis gyro and 3-axis accelerometer. I guess the microcontroller could be doing the quaternion calculations. Are you sure it is gyro data and not maybe orientation data derived from gyro + accel? Try spinning it around an axis and integrate the output in a script (provided you knew the resolution in units per deg/s or rad/s). Some devices may use 1D or 2D sensors, so if for those just ABS_GYRO_X / _Y for them, for a 4th dimension _W would make sense I guess. -- 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
