From mboxrd@z Thu Jan 1 00:00:00 1970 From: Randy Dunlap Subject: Re: PROBLEM: USB keyboards works only 4 per PC host port Date: Mon, 18 Aug 2008 08:14:32 -0700 Message-ID: <20080818081432.782d9632.rdunlap@xenotime.net> References: <200808080702.24969.aivils@latnet.lv> <200808100408.37473.aivils@latnet.lv> <20080814184948.093d2cad.rdunlap@xenotime.net> <200808181642.49489.aivils@latnet.lv> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from xenotime.net ([66.160.160.81]:57628 "HELO xenotime.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750907AbYHRPOC convert rfc822-to-8bit (ORCPT ); Mon, 18 Aug 2008 11:14:02 -0400 Received: from chimera.site ([72.90.117.230]) by xenotime.net for ; Mon, 18 Aug 2008 08:13:56 -0700 In-Reply-To: <200808181642.49489.aivils@latnet.lv> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Aivils Stoss Cc: lud , Samuel Thibault , linux-input@vger.kernel.org, jkosina@suse.cz, linux-kernel@vger.kernel.org, linuxconsole-dev@lists.sourceforge.net On Mon, 18 Aug 2008 16:42:49 +0530 Aivils Stoss wrote: > On Friday 15 August 2008 7:19:48 am Randy Dunlap wrote: > > On Sun, 10 Aug 2008 04:08:37 +0100 Aivils Stoss wrote: > > > On Saturday 09 August 2008 11:42:26 am Samuel Thibault wrote: > > > > Aivils Stoss, le Fri 08 Aug 2008 07:02:24 +0100, a =E9crit : > > > > > I suppose this is Linux kernel bug because i test keyboards u= nder > > > > > Windows, which support any schema of cascading of usb hubs. > > > > > > > > On the very same machine and hubs? > > > > > > Yes, on same machine. Under Windows i don't have evdev interface, > > > checked only how keypress go to console. > > > Of course to repeat a try You must have at least 5 keyboards and > > > 1 7-port or 2 4-port hubs and kernel 2.6.22 and above. I allways > > > got result - 5th, 6th, 7th keyboard does not send events to conso= le > > > or evdev. > > > > [adding linux-usb mailing list] > > > > Hi, > > > > I finally got 5 USB keyboards together along with 2 hubs. > > I daisy-chained the hubs and connected 1 keyboard to the hub that i= s > > on the notebook computer USB port, then I connected 4 keyboards to = the > > second hub. They all worked for me, meaning that I can type on all= of > > them and have their characters show up on my console. > > > > I'm testing with 2.6.7-rc2. > > 'usbtree' output of the USB subsystem is attached. >=20 > Yeah! 2.6.7 is a bit obsolete. At my end 2.6.15 support more than 4 > keyboards per PC port , but mess up input when is plugged more than > 9 keyboards. 10th is capable to send keypress events, but last presse= d > key will be repeated until ctrl-c . 10th keyboard disturb an auto rep= eat of=20 > all keyboards. Sorry, my keyboard made a typo. I'm testing with 2.6.27-rc2. So the problem is now different from your original report, right? What speed is the host port that the keyboards are connected to? Could it be a USB bus bandwidth limitation? (not that any code checks for that) I barely found 5 USB keyboards, so I surely can't test 10 or more. ;) I suppose that it will take some USB debug messages to attempt to see what is going on... --- ~Randy Linux Plumbers Conference, 17-19 September 2008, Portland, Oregon USA http://linuxplumbersconf.org/ -- To unsubscribe from this list: send the line "unsubscribe linux-input" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html