Re: ehci driver disables USB support on boot time

From: Doug White <dwhite_at_gumbysoft.com>
Date: Mon, 29 Dec 2003 20:55:10 -0800 (PST)
On Fri, 26 Dec 2003, FUJIMOTO Kou wrote:

> Enabling "device ehci" on 5.2-RC kernel config and rebooting,
> both uhci and ehci devices are recognized as below.
> On the next boot time, however, LEDs on HUBs don't light
> and keyboard don't work until kernel loads USB drivers.
> After USB controllers are recognized by kernel, LEDs are on and
> keyboard/mouse work properly.
>
> It looks like that BIOS USB support is disabled, but it is
> actually enabled on BIOS setup menu.

If it works on a cold boot OK, then its a bug in your BIOS -- if it wants
to use the USB ports then it needs to take the necessary steps to reset
the chips in the warm boot case.  It shouldn't be assuming they will be in
the power-on state after a CPU reset. Or its a bug in the chips not
resetting properly. Or something :)

Legacy USB keyboard support has always been flakey.  I have yet to find a
motherboard whos implementation of this feature actually works the
majority of the time. Rather disappointing since I'd like to switch over
to USB fully.

-- 
Doug White                    |  FreeBSD: The Power to Serve
dwhite_at_gumbysoft.com          |  www.FreeBSD.org
Received on Mon Dec 29 2003 - 19:55:14 UTC

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