Increasing USB driver priorities

I have developed an USB driver for an own data acquistion card, and everything goes fine.

Now, i’m interested in running such program with a higher priority level (i.e: 50) but my QNX Neutrino 6.3.2 machine gets blocked (at least mouse and keyboard don’t answer), i have had to push the reset button.

I thought it’s an io-usb driver issue, so, I killed this process and i started it again with an increased priority level by using:

nice -n-40 io-usb -dehci -dohci -duhci

But the problem persists.

How could i solve this problem?

Thanks in advance,



What kind of USB driver have you developed?

In other words, is your data acquisition card a HID device by chance?

You need to make sure your own USB driver is not interfering with the QNX HID driver that registers with io-usb.

From what I recall a while ago (more than a year so my memory is getting fuzzy) when I was developing a USB driver I had to be very careful not to step on the toes of devi-hid which registers to get all HID devices (mice, keyboards etc). So make sure your own USB driver is only registering to get JUST your card.


Hi Tim,

Thanks for your reply,

yeah, mi daq is very simple, it’s vendor specific and uses only control transfers through the endpoint 0. My machine is old, so its mouse and keyboard are ps/2.




Problem solved, i had an stupid “busy wait” when using a mutex.