From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753387Ab2KMNMW (ORCPT ); Tue, 13 Nov 2012 08:12:22 -0500 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:57671 "EHLO opensource.wolfsonmicro.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751499Ab2KMNMV (ORCPT ); Tue, 13 Nov 2012 08:12:21 -0500 Date: Tue, 13 Nov 2012 13:12:19 +0000 From: Charles Keepax To: Mark Brown Cc: sameo@linux.intel.com, patches@opensource.wolfsonmicro.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mfd: arizona: Move chip reset to before register patch Message-ID: <20121113131219.GA29198@opensource.wolfsonmicro.com> References: <20121112175648.GA29044@opensource.wolfsonmicro.com> <20121113055618.GC18224@opensource.wolfsonmicro.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121113055618.GC18224@opensource.wolfsonmicro.com> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 13, 2012 at 02:56:20PM +0900, Mark Brown wrote: > On Mon, Nov 12, 2012 at 05:56:48PM +0000, Charles Keepax wrote: > > In the absence of a physical reset line the chip is reset by writing the > > first register, this was done after the register patch was applied which > > negates the settings applied in the register patch. > > > > This patch moves the reset to take place before the register patch is > > applied. > > No, we should never write to the chip until we have successfully > identified it. Do a sync or similar instead (we should be triggering > this very soon afterwards via runtime PM anyway). In that case I would be inclined to seperate out the chip identification and the register patch doing the reset in between. Is this something that would sound reasonable or would you rather just add a sync after the reset?