From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from fmmailgate01.web.de ([217.72.192.221]:53300 "EHLO fmmailgate01.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752707AbZGaSpH (ORCPT ); Fri, 31 Jul 2009 14:45:07 -0400 Received: from smtp06.web.de (fmsmtp06.dlan.cinetic.de [172.20.5.172]) by fmmailgate01.web.de (Postfix) with ESMTP id 3073A10F2220A for ; Fri, 31 Jul 2009 20:45:07 +0200 (CEST) Received: from [217.228.167.87] (helo=[172.16.99.2]) by smtp06.web.de with asmtp (TLSv1:AES256-SHA:256) (WEB.DE 4.110 #277) id 1MWx6H-00025q-00 for linux-media@vger.kernel.org; Fri, 31 Jul 2009 20:45:05 +0200 Message-ID: <4A733BAB.6080305@magic.ms> Date: Fri, 31 Jul 2009 20:44:59 +0200 From: emagick@magic.ms MIME-Version: 1.0 To: linux-media@vger.kernel.org Subject: Re: Cinergy T2 stopped working with kernel 2.6.30 References: <4A61FD76.8010409@magic.ms> In-Reply-To: <4A61FD76.8010409@magic.ms> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: I think I've found the problem: ------------------------------------------------------------------------ static int cinergyt2_fe_set_frontend(struct dvb_frontend *fe, struct dvb_frontend_parameters *fep) { struct cinergyt2_fe_state *state = fe->demodulator_priv; struct dvbt_set_parameters_msg param; char result[2]; int err; param.cmd = CINERGYT2_EP1_SET_TUNER_PARAMETERS; param.tps = cpu_to_le16(compute_tps(fep)); param.freq = cpu_to_le32(fep->frequency / 1000); param.bandwidth = 8 - fep->u.ofdm.bandwidth - BANDWIDTH_8_MHZ; err = dvb_usb_generic_rw(state->d, (char *)¶m, sizeof(param), result, sizeof(result), 0); ------------------------------------------------------------------------ As dvbt_set_parameters_msg is declared with __attribute__((packed)), its alignment is 8 bits. In fact, cinergyt2_fe_set_frontend()'s param variable is not aligned on a 32-bit boundary. Note that param is passed to usb_bulk_msg(). This seems to cause DMA problems on my hardware (Atom N270 + 945GSE + ICH7M). I hope that I'm not talking to a black hole.