Re: New EHCI device ID

From: Bernd Walter <ticso_at_cicely12.cicely.de>
Date: Mon, 10 Nov 2003 16:19:27 +0100
On Mon, Nov 10, 2003 at 03:54:23PM +0100, Alexander Leidinger wrote:
> On Mon, 10 Nov 2003 13:55:39 +0100
> Bernd Walter <ticso_at_cicely12.cicely.de> wrote:
> 
> > But ehci doesn't control low/full speed ports.
> > The physical ports are multiplexed between ehci and ohci/uhci ports.
> > The switching is done without driver interaction.
> 
> Attached to the port is a
> 
> uhub1: NEC Corporation USB2.0 Hub Controller, class 9/0, rev 2.00/1.00, addr 2
> uhub1: 4 ports with 4 removable, self powered

USB2 hubs are currently not supported with high speed uplinks.
That's the reason why there is no EHCI support in GENERIC.
EHCI needs interrupt transfers first to support usb2.0 hubs at high
speed uplinks with high speed devices.
For low and full speed downlink we additionaly need speed conversion
support in uhub code.

-- 
B.Walter                   BWCT                http://www.bwct.de
ticso_at_bwct.de                                  info_at_bwct.de
Received on Mon Nov 10 2003 - 06:19:36 UTC

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