Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262495AbVBXVj0 (ORCPT ); Thu, 24 Feb 2005 16:39:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262489AbVBXVjZ (ORCPT ); Thu, 24 Feb 2005 16:39:25 -0500 Received: from hell.sks3.muni.cz ([147.251.210.30]:40659 "EHLO hell.sks3.muni.cz") by vger.kernel.org with ESMTP id S262495AbVBXVjA (ORCPT ); Thu, 24 Feb 2005 16:39:00 -0500 Date: Thu, 24 Feb 2005 22:38:53 +0100 From: Lukas Hejtmanek To: Greg KH Cc: Matthias-Christian Ott , linux-kernel@vger.kernel.org Subject: Re: USB 2.0 Mass storage device Message-ID: <20050224213853.GA8646@mail.muni.cz> References: <20050224175918.GA7627@mail.muni.cz> <20050224181347.GA10847@kroah.com> <20050224182300.GA7778@mail.muni.cz> <20050224184928.GA11490@kroah.com> <20050224190548.GA7978@mail.muni.cz> <20050224191243.GD11806@kroah.com> <20050224191809.GB7978@mail.muni.cz> <20050224192207.GB12018@kroah.com> <421E34B1.9050803@tiscali.de> <20050224211512.GC24969@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-2 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20050224211512.GC24969@kroah.com> X-echelon: NSA, CIA, CI5, MI5, FBI, KGB, BIS, Plutonium, Bin Laden, bomb User-Agent: Mutt/1.5.6+20040907i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1809 Lines: 47 On Thu, Feb 24, 2005 at 01:15:12PM -0800, Greg KH wrote: > And if you look at the raw descriptors, which is what is displayed in > /proc/bus/usb/devices in human readable form, the device itself tells > the computer what speed it supports. The host never tells the device > what speed to run at. I do not think so. This is another device (Card reader) supporting USB 2.0. In this case I used only uhci_hcd driver and it reports speed 12. T: Bus=04 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 3 Spd=12 MxCh= 0 D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=05dc ProdID=b018 Rev= 1.28 S: Manufacturer=Lexar Media S: Product=Multi-Card Reader S: SerialNumber=0000246504 C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=500mA I: If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage E: Ad=81(I) Atr=02(Bulk) MxPS= 64 Ivl=0ms E: Ad=02(O) Atr=02(Bulk) MxPS= 64 Ivl=0ms In this case I used both ehci_hcd and uhci_hcd drivers (ehci detected device) and it reports speed 480. T: Bus=01 Lev=01 Prnt=01 Port=04 Cnt=01 Dev#= 2 Spd=480 MxCh= 0 D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=05dc ProdID=b018 Rev= 1.28 S: Manufacturer=Lexar Media S: Product=Multi-Card Reader S: SerialNumber=0000246504 C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=500mA I: If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage E: Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms So for me it looks like it reports speed according to USB driver or negotiated speed. -- Luk?? Hejtm?nek - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/