Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753893AbZF1UUq (ORCPT ); Sun, 28 Jun 2009 16:20:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752062AbZF1UUi (ORCPT ); Sun, 28 Jun 2009 16:20:38 -0400 Received: from smtp-out002.kontent.com ([81.88.40.216]:60095 "EHLO smtp-out002.kontent.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752028AbZF1UUh (ORCPT ); Sun, 28 Jun 2009 16:20:37 -0400 From: Oliver Neukum To: Arseniy Lartsev , USB list Subject: Re: PROBLEM: USB ACM device does not work Date: Sun, 28 Jun 2009 22:20:49 +0200 User-Agent: KMail/1.10.3 (Linux/2.6.30-0.1-default; KDE/4.1.3; x86_64; ; ) Cc: linux-kernel@vger.kernel.org References: <200906282229.35713.ars3n@yandex.ru> In-Reply-To: <200906282229.35713.ars3n@yandex.ru> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200906282220.50313.oliver@neukum.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1069 Lines: 23 Am Sonntag, 28. Juni 2009 20:29:26 schrieb Arseniy Lartsev: > I've got a piece of hardware (this one: > http://masterkit.ru/main/set.php?num=1153) which acts like an USB ACM > device and is handeled by the cdc_acm module. /dev/ttyACM0 does appear > but any attempt to write something to the device with a simple > "echo something >/dev/ttyACM0" fails with "Invalid argument" error. > > The reason is that the driver calls usb_submit_urb in acm_start_wb() > but doesn't set interval in the urb structure, so it remains zero and > causes usb_submit_urb to return -EINVAL. Reading from device also does > not work due to the same problem in acm_rx_tasklet(). This is supposed to write to bulk endpoints. There's no reason interval would need to be specified. Something is very odd. Please post "lsusb -v". 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/