From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757531AbcAJVd5 (ORCPT ); Sun, 10 Jan 2016 16:33:57 -0500 Received: from muin.pair.com ([209.68.1.55]:52089 "EHLO muin.pair.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757293AbcAJVd4 (ORCPT ); Sun, 10 Jan 2016 16:33:56 -0500 Subject: Re: [PATCH 1/3] ASoC: fsl_ssi: mark SACNT register volatile To: "Maciej S. Szmigiero" , "alsa-devel@alsa-project.org" Cc: Nicolin Chen , Xiubo Li , Liam Girdwood , Mark Brown , "linuxppc-dev@lists.ozlabs.org" , linux-kernel , Fabio Estevam References: <56770FE1.4060202@maciej.szmigiero.name> From: Timur Tabi Message-ID: <5692CE43.20708@tabi.org> Date: Sun, 10 Jan 2016 15:33:55 -0600 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:42.0) Gecko/20100101 Firefox/42.0 SeaMonkey/2.39 MIME-Version: 1.0 In-Reply-To: <56770FE1.4060202@maciej.szmigiero.name> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Maciej S. Szmigiero wrote: > + regmap_write(regs, CCSR_SSI_SACNT, > + ssi_private->regcache_sacnt); So I'm not familiar with all of the regcache features, but I understand this patch. I was wondering if it makes sense to write the same exact value that was read previously. Isn't it possible for the WR or RD bits to change between fsl_ssi_suspend() and fsl_ssi_resume()? That is, should we be doing this instead? u32 temp; regmap_read(regs, CCSR_SSI_SACNT, &temp); temp &= 0x18; // preserve WR and RD regmap_write(regs, CCSR_SSI_SACNT, (ssi_private->regcache_sacnt & ~0x18) | temp);