NetBSD Problem Report #19333

Received: (qmail 22774 invoked by uid 605); 9 Dec 2002 17:06:35 -0000
Message-Id: <>
Date: Mon, 9 Dec 2002 09:05:53 -0600 (CST)
From: seebs <>
Subject: Some USB->PS/2 adapters unusably slow?
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>Number:         19333
>Category:       kern
>Synopsis:       On some adapters, keypresses take about 1/4 second
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Dec 09 17:07:00 +0000 2002
>Originator:     seebs
>Release:        NetBSD 1.6K

System: NetBSD 1.6K NetBSD 1.6K (VASH) #1: Mon Dec 9 08:50:42 CST 2002 i386
Architecture: i386
Machine: i386
	I have a couple of USB keyboard adapters, which look like

ukbd0 at uhidev0 reportid 1
ukbd: imod=0 usage=0x700e0 flags=0x2 pos=0 size=1 cnt=1
wskbd1 at ukbd0 mux 1

ukbd1 at uhidev1
ukbd: imod=0 usage=0x700e0 flags=0x2 pos=0 size=1 cnt=1
wskbd2 at ukbd1 mux 1

	The first one is built into a multifunction hub; the second is a
	standalone adapter.

	The first one consistently takes about 1/4 second to process a key
	press; the second has normal responsiveness.

	Experimenting, I have found that the press and release interrupts
	seem to be coming in a slow but regular stream from the first
	device, but working fine on the second.

	More interestingly, I have two hubs which exhibit exactly the same
	1.  Keyboard interrupts are unusably slow.
	2.  Mouse interrupts are fine.
	3.  The USB ports on the hub are totally silent; plugging devices
	into them has no effect.

	One is a D-Link hub, the other is a "QVS" hub.  Both have serial
	ports (uftdi), keyboard, mouse, and other USB ports.  One also has
	an ethernet and parallel port controller.

	Plug one of these hubs in.

	None figured out.  I know that both of these devices were known
	to work a couple of months ago, and I think this is probably a hub
	driver problem, not a keyboard driver problem.  I'm still poking
	around at it.

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