On Mon, Oct 05, 2020 at 09:00:10PM +0200, Michał Mirosław wrote: > On Mon, Oct 05, 2020 at 10:36:36AM -0700, dmitry.torokhov@xxxxxxxxx wrote: > > Hi Michał, > > > > On Mon, Oct 05, 2020 at 01:09:08PM +0200, Michał Mirosław wrote: > > > and breaking the loop will desync touch > > > state (I would guess this would be noticable by next user). > > Upon next open driver will service the interrupt and provide new set of > > touch coordinates. Userspace is supposed to query current state of > > device when opening it before starting processing events. Or you are > > concerned about some other state? > > From the code I would expect that there is a slight window, wher when the > user releases the touch between close() and open(), the client that open()s > will see a 'pressed' state until the ISR runs again (probably immediately > because of pending interrupt). OTOH, maybe the app should be prepared > for that anyway? I think users should be prepared for it. There could be many users, so anyone opening interface device (evdev or similar) can not expect that the hardware device is in a quiesce state; it could just happen that finger was on the surface and will be released as someone is opening the device anyway. Thanks. -- Dmitry
