Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755305AbZGAK4o (ORCPT ); Wed, 1 Jul 2009 06:56:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753901AbZGAK4f (ORCPT ); Wed, 1 Jul 2009 06:56:35 -0400 Received: from smtp-out003.kontent.com ([81.88.40.217]:37863 "EHLO smtp-out003.kontent.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753211AbZGAK4e (ORCPT ); Wed, 1 Jul 2009 06:56:34 -0400 From: Oliver Neukum To: Arseniy Lartsev Subject: Re: PROBLEM: USB ACM device does not work Date: Wed, 1 Jul 2009 12:56:46 +0200 User-Agent: KMail/1.10.3 (Linux/2.6.30-0.1-default; KDE/4.1.3; x86_64; ; ) Cc: Alan Stern , USB list , linux-kernel@vger.kernel.org References: <200907011301.06574.ars3n@yandex.ru> In-Reply-To: <200907011301.06574.ars3n@yandex.ru> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200907011256.47550.oliver@neukum.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1201 Lines: 33 Am Mittwoch, 1. Juli 2009 11:01:06 schrieb Arseniy Lartsev: > On Wednesday 01 July 2009 01:01:00 Alan Stern wrote: > > This looks like your problem. Low-speed devices are not allowed to > > have bulk endpoints. Linux internally changes them to interrupt > > endpoints with interval = 1 and maxpacket size no larger than 8. > > Maybe this device is a little "buggy". But Linux should support buggy > devices as well. Yes, it should. We just needed to understand why it failed. > + ep = (usb_pipein(acm->rx_endpoint) ? acm->dev->ep_in : acm->dev->ep_out) > + [usb_pipeendpoint(acm->rx_endpoint)]; > + if (usb_endpoint_xfer_int(&ep->desc)) > + usb_fill_int_urb(rcv->urb, acm->dev, > + acm->rx_endpoint, > + buf->base, > + acm->readsize, > + acm_read_bulk, rcv, 0xff); The patch is good except for this. We should make sure this interval matches usbcore's value. Would you care to redo it with that change? Regards Oliver -- 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/