From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757506Ab1KQNli (ORCPT ); Thu, 17 Nov 2011 08:41:38 -0500 Received: from corega.com.ru ([195.178.208.66]:47000 "EHLO tservice.net.ru" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1756744Ab1KQNlh (ORCPT ); Thu, 17 Nov 2011 08:41:37 -0500 X-Greylist: delayed 552 seconds by postgrey-1.27 at vger.kernel.org; Thu, 17 Nov 2011 08:41:36 EST Date: Thu, 17 Nov 2011 16:32:20 +0300 From: Evgeniy Polyakov To: Maciej Szmigiero Cc: Andrew Morton , Christian Glindkamp , linux-kernel@vger.kernel.org, Greg KH Subject: Re: [PATCH][W1]w1_therm: release the bus during conversion on externally powered devices Message-ID: <20111117133220.GA28213@ioremap.net> References: <4EC2F914.4010302@o2.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4EC2F914.4010302@o2.pl> 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 +gregkh On Wed, Nov 16, 2011 at 12:43:16AM +0100, Maciej Szmigiero (mhej@o2.pl) wrote: > w1_therm devices can either be bus powered or externally powered. > > When device is bus powered during temperature conversion the bus > have to be left high to provide necessary power. Some masters also allow > strong power-up to be enabled in this case. > Naturally, no communication over bus can occur during that time. > > However, if device has external power then there is no such restriction, > and host can talk to other devices during temperature conversion. > > There is command which allows us to check how device is powered, > this patch uses it to release the bus on externally w1_therm powered devices > during temperature conversion. > > Also, this changes uninterruptible sleeps there into interruptible ones to > avoid long uninterruptible sleep if w1 subsystem happens to grab bus for > scan during w1_therm_read(). Patch looks good, but I do not have such hardware to test it. So, if it doesn't break things I'm ok to push it upstream. Greg, please pull it into your tree, thank you. > Signed-off-by: Maciej Szmigiero Acked-by: Evgeniy Polyakov -- Evgeniy Polyakov