From owner-freebsd-usb@FreeBSD.ORG Sun Dec 26 16:47:14 2004 Return-Path: Delivered-To: freebsd-usb@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 62FA716A4CE for ; Sun, 26 Dec 2004 16:47:14 +0000 (GMT) Received: from mailfe04.swip.net (mailfe04.swip.net [212.247.154.97]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9E7A643D2F for ; Sun, 26 Dec 2004 16:47:13 +0000 (GMT) (envelope-from hselasky@c2i.net) X-T2-Posting-ID: gvlK0tOCzrqh9CPROFOFPw== Received: from mp-217-207-83.daxnet.no ([193.217.207.83] verified) by mailfe04.swip.net (CommuniGate Pro SMTP 4.2.7) with ESMTP id 255334768 for freebsd-usb@freebsd.org; Sun, 26 Dec 2004 17:47:12 +0100 From: Hans Petter Selasky To: freebsd-usb@freebsd.org Date: Sun, 26 Dec 2004 17:47:36 +0100 User-Agent: KMail/1.7 References: <41CB38A7.5020700@vicor.com> <41CB4BCB.1080708@elischer.org> <20041224124346.GG45586@cicely12.cicely.de> In-Reply-To: <20041224124346.GG45586@cicely12.cicely.de> MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200412261747.36555.hselasky@c2i.net> Subject: Re: USB vendore designations.. X-BeenThere: freebsd-usb@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: hselasky@c2i.net List-Id: FreeBSD support for USB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 26 Dec 2004 16:47:14 -0000 On Friday 24 December 2004 13:43, Bernd Walter wrote: > On Thu, Dec 23, 2004 at 02:50:51PM -0800, Julian Elischer wrote: > > EHCI is almost ok.. except for where it REALLY SUCKS! > The EHCI manual says that QH's can be removed without stopping the HC. QH removal is done like this: set the previous QH to point to the next QH, and then set the DOORBELL bit in the EHCI command register and wait for it to clear. This is the same whether the QH is finished or cancelled, though if it is finished one might get around with a short DELAY(), hence the HC should already be skipping the QH? Currently, no driver is checking cancelled QH's, to see if they were finished after all. If the drivers did, then no information as to whether the transfers on it were completed or not, would be lost. As long as there are not so many transfers the EHCI is not that inefficient. Yours --HPS