From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754951Ab1IGRvX (ORCPT ); Wed, 7 Sep 2011 13:51:23 -0400 Received: from corega.com.ru ([195.178.208.66]:33487 "EHLO tservice.net.ru" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751223Ab1IGRvW (ORCPT ); Wed, 7 Sep 2011 13:51:22 -0400 Date: Wed, 7 Sep 2011 21:50:59 +0400 From: Evgeniy Polyakov To: Jan Weitzel Cc: linux-kernel@vger.kernel.org Subject: Re: [RFC] w1: Disable irqs in critical section Message-ID: <20110907175059.GA12074@ioremap.net> References: <1315385312-1176-1-git-send-email-j.weitzel@phytec.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1315385312-1176-1-git-send-email-j.weitzel@phytec.de> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 07, 2011 at 10:48:32AM +0200, Jan Weitzel (j.weitzel@phytec.de) wrote: > Interrupting w1_delay in w1_read_bit results in missing the low level > on the w1 line and receiving "1" instead of "0". > Adding local_irq_save / local_irq_restore around the critical section This means that CPU will be essentially stuck for 15 useconds for every bit transferred, doesn't really look like a good idea. Are you absolutely sure that missing bit is because of timings and not some other bug? -- Evgeniy Polyakov