From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935705AbcKWQno (ORCPT ); Wed, 23 Nov 2016 11:43:44 -0500 Received: from out5-smtp.messagingengine.com ([66.111.4.29]:46701 "EHLO out5-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752487AbcKWQnl (ORCPT ); Wed, 23 Nov 2016 11:43:41 -0500 X-ME-Sender: X-Sasl-enc: a0j/mwGYhYbPjKnNRBXLEVYgDsKiEg9M5MDLY293ego/ 1479918935 Date: Wed, 23 Nov 2016 17:35:45 +0100 From: Greg KH To: Wolfgang Wilhelm Cc: linux-usb@vger.kernel.org, Austin S Hemmelgarn , linux-kernel@vger.kernel.org Subject: Re: Problem with USB driver using two devices Message-ID: <20161123163545.GB10750@kroah.com> References: <55FABF0F.5831.182EDC5@wilhelm.fastcomtec.com> <5835962F.20615.B8710F6@wilhelm.fastcomtec.com> <20161123145747.GA4137@kroah.com> <5835C11F.28335.C2ECC3B@wilhelm.fastcomtec.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5835C11F.28335.C2ECC3B@wilhelm.fastcomtec.com> User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 23, 2016 at 05:17:35PM +0100, Wolfgang Wilhelm wrote: > Thankyou very much for the really fast answer. > > I don't get any error messages and I can communicate with > the driver for the second device via ioctrl and write functions, > i.e. write registers and read registers via the RBUF ioctrl function, > only the read function for the second device does not work, > i.e. no data is obtained from the mcs6_read function for the > second device. Hm, let me go look at the driver again, maybe something's odd with it. > Thankyou for your hint using libusb, I will have a look on it. > > Our USB device has three endpoints, two with 64 kb packet size > for reading and writing registers (I know this is not standard > for high speed) and one with 512 kb packet size for reading data. > Do you think the problem could arise from this deviation > from the USB standard? No, it should be fine, the USB standard only care about endpoint sizes, not logical "packet" sizes, right? > Of course we would be happy if our driver could be merged into > the Linux kernel. If you can use libusb, I'd strongly recommend using that and not a kernel driver at all, as we don't like adding kernel drivers where they are not needed. > Our device uses the same vendor/product id's as a > "D-Link DSB-R100 USB FM radio" dsbr100, that has a built-in > driver in some Linux distributions, so that dsbr100 must be > blacklisted in /etc/modprobe.d/fbdev-blacklist.conf for > using our driver. Does your device work like the USB FM radio device? Why is the same vendor/device id being used here? They are supposed to be unique for different types of devices. > Which security problems do you see in the code? No checking that the values given to you by userspace are actually valid and within "sane" ranges :) thanks, greg k-h