[quoted lines by Luke-Jr on 2014/02/23 at 19:03 +0000] >I was looking at the circumstances surrounding ftdi_sio, which uses the >generic implementation. > >wouldn't it be possible to just ask less often to >reduce the bandwidth load?
That's sort of what we do in brltty's user-space implementation for serial adapters which use bulk input endpoints. And, yes, the ftdi_sio chip is a problem since it always has pending data (even if it's just status bits). What we do is back off by increasing the delay by powers of 2 up to a maximum as long as we're only getting status bytes, but go back to immediate as soon as we get data. We also only use a single URB. It works quite well. -- Dave Mielke | 2213 Fox Crescent | The Bible is the very Word of God. Phone: 1-613-726-0014 | Ottawa, Ontario | http://Mielke.cc/bible/ EMail: d...@mielke.cc | Canada K2A 1H7 | http://FamilyRadio.com/ -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html