From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Brownell Subject: Re: [linux-usb-devel] Re: [PATCH] USB changes for 2.5.58 Date: Mon, 20 Jan 2003 14:26:08 -0800 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <3E2C7780.2080307@pacbell.net> References: <10426732153816@kroah.com> <200301202148.23210.oliver@neukum.name> <3E2C68F8.7080405@pacbell.net> <200301202251.08356.oliver@neukum.name> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7BIT Return-path: Received: from pacbell.net ([67.118.247.72]) by mta6.snfc21.pbi.net (iPlanet Messaging Server 5.1 HotFix 1.6 (built Oct 18 2002)) with ESMTP id <0H91002MZ9Z3J8@mta6.snfc21.pbi.net> for linux-scsi@vger.kernel.org; Mon, 20 Jan 2003 14:18:42 -0800 (PST) List-Id: linux-scsi@vger.kernel.org To: Oliver Neukum Cc: Luben Tuikov , Matthew Dharm , Mike Anderson , Greg KH , linux-usb-devel@lists.sourceforge.net, Linux SCSI list Oliver Neukum wrote: > I should be more specific. Yes... > The SCSI is different for several reasons: > - we are talking about bus as well as device detection > - there's no common way to probe for devices > (the probing of LUNs works only on conventional busses) So the SCSI stack needs to support more than one model for device/bus detection. This can't be news. And some of them have to handle "conventional" busses, like USB and PCI; maybe even handle booting off them... > - many SCSI devices are not really SCSI devices. They just use > the command set > > SCSI hotplug detection doesn't work for the same reason that USB > can handle only detection of devices by itself. Busses on the other > hand are not handled by USB itself. Just how is it that USB doesn't handle USB? "B" == "Bus" ... :) If you mean that HCs hook up to a different bus (often PCI), with its own hotplug support, that doesn't seem so different from SCSI HBAs hooking up to such busses (often PCI) and cascading the same hotplug support... >>Erm ... which of the three SCSI layers are you talking about? I was >>talking about the highest level,.. > > > In SCSI view device and bus disconnection is recognised by the lowest > level. As it knows nothing about the high layers, it notifies the midlayer So you were talking past what I said about notifying that highest level, not disagreeing with it.