Hi Yufeng, On Thu, Jan 30, 2014 at 5:52 PM, Yufeng Shen <miletus@xxxxxxxxxxxx> wrote: > Hi, > > I was under the impression that in recent kernel (I am testing on 3.8) > hid-multitouch > is the default driver for touchscreen. yes, and no. hid-multitouch is the default for Win 7 / Win 8 certified touchscreens, which tends to be a lot. For instance, here is a list of device I know of: http://lii-enac.fr/en/architecture/linux-input/multitouch-devices.html So given that on x86 most manufacturers wants the Microsoft certification, their devices use hid-multitouch. However, on the Android side, or the embedded world more generally, people use their own protocol and communication bus and they have to write their own driver. Side note, I think they should consider switching to HID over i2c, they will not need to write any driver this way. But that's just my opinion. > And I found one case that there is this > RNDPLUS PulseIR Touchscreen pid/vid 2512:5004 defaults to generic-usb driver. Hmm... the RNDPLUS 5003 (as written in the table I mentioned above) uses hid-multitouch. And given the fact that you refer to generic-usb driver, I think (but I may be wrong) that last time you checked this device, it was on a kernel before 3.2. Now it should be handled by hid-multitouch. Or it is just a single touch touchscreen. > > If you search > "HID-Multitouch Kernel Driver Installation for Android OS IDSPulse" > there is a setup document shows one need to add its pid/vid to > hid_have_special_driver[] > list so it will pick up hid-multitouch. Do we still need to do that > in recent kernel ? No. - Starting from 3.2 multitouch devices where rejected by hid-core and had to be added manually to hid-multiouch - in 3.4, there were a non generic attempt to automatically bind them to hid-multitouch (attempt which was doing its job though) - starting from 3.5, there is a much better generic solution and multitouch screens are bound to hid-multitouch, and sensors to hid-sensorhub for instance. So to sum up, no, multitouch screen do not need to be added to hid_have_special_driver[] except some rare cases which are already in the kernel. Cheers, Benjamin > > > Thanks, > > Yufeng Shen > -- > 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 -- 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
