umcs (4-Port-USB-serial) triggering way too much ehci IRQs

Lev Serebryakov lev at
Tue Sep 17 08:41:26 UTC 2013

Hello, Hans.
You wrote 17 сентября 2013 г., 9:14:17:

HPS> Check using usbdump -i usbusX -f Y -s 65536 -vvv
HPS> what is going on. Maybe some USB transfers are returning zero length data from the chip.
  After closing port I disable all interrupts in chip, I've checked this (it
 was my first thought: ``I forget to disable internal interrupts on device
 close''), so, theoretically, it should stop spam system with interrupts...

// Black Lion AKA Lev Serebryakov <lev at>

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