On 2017-05-18 11:21, Sriram V wrote: > Hi, > > I wanted to find out how does touch calibration works? Is this > something that is taken care in the userspace? > Unfortunately, my device does not have a Write Interface. I have read > the values from the device but can't do i2c writes to the device. > I also wanted to find out how touch screen calibration is done in > Android systems. > Calibration is linear transformation of coordinate values. Usually this is not a driver's work. The driver should make sure userspace can talk in "evdev" sync frames. It is usually done in userspace, by an X.org input "driver" for example. At least I think xf86-input-evdev does some calibration. For touchscreen devices, especially in embedded and if people need more filters than linear transormation, tslib ( http://tslib.org ) is often used for calibration. The one tslib module doing calibration is called "linear" and can be configured (the actual calibration process) with a graphical framebuffer application, ts_calibrate which is part of tslib. martin ________________________________ Ginzinger electronic systems GmbH Gewerbegebiet Pirath 16 4952 Weng im Innkreis www.ginzinger.com Firmenbuchnummer: FN 364958d Firmenbuchgericht: Ried im Innkreis UID-Nr.: ATU66521089 -- 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
