Hi everyone, I just found about an issue in the downstream Raspberry Pi[1] kernel that I wonder if it'd be worth fixing generally. The official RPi DSI display touchscreen uses the polled input interface. The ts chip works at around 60Hz, and that's the period the driver is configured to use (17ms). This doesn't play too good on systems with low HZ (100/250). Users complain that in practice they experience, at worst, half the event rate. This is due to the rounding error when converting milliseconds to jiffies, general system delays, and what not. We could somewhat fix this in the driver (raspberrypi-ts.c) by playing with the poll rate. But it seems pretty hacky and would ultimately stress the CPU unnecessarily. I wonder to what extent it makes sense to move the implementation to using hrtimers whenever the poll period is in the same order of magnitude as HZ's delta. Any ideas/comments? Regards, Nicolas [1] https://github.com/raspberrypi/linux/issues/3777#issuecomment-698346991
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