Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753190Ab3DOOLj (ORCPT ); Mon, 15 Apr 2013 10:11:39 -0400 Received: from mail-pd0-f173.google.com ([209.85.192.173]:56715 "EHLO mail-pd0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752136Ab3DOOLi convert rfc822-to-8bit (ORCPT ); Mon, 15 Apr 2013 10:11:38 -0400 MIME-Version: 1.0 X-Originating-IP: [1.173.65.30] In-Reply-To: <516BF56A.5010401@stericsson.com> References: <1365424274.21989.2.camel@phoenix> <516BB444.7010508@stericsson.com> <516BE5AE.3020703@stericsson.com> <516BF56A.5010401@stericsson.com> Date: Mon, 15 Apr 2013 22:11:36 +0800 Message-ID: Subject: Re: [PATCH] regulator: ab8500: Fix get_mode for shared mode regulators From: Axel Lin To: =?ISO-8859-1?Q?Bengt_J=F6nsson?= Cc: Mark Brown , Lee Jones , Yvan FILLION , Liam Girdwood , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1797 Lines: 48 2013/4/15 Bengt J?nsson : > On 04/15/2013 02:13 PM, Axel Lin wrote: >>> >>> I guess what you don't like with the current approach is that the driver >>> returns REGULATOR_MODE_IDLE in some cases where the mode register is set >>> to >>> LP. But I think, with patch applied, the control may be wrong in some >>> cases >>> because the regulator framework will call get_mode and see that the mode >>> is >>> already correct and not call set_mode so lp_mode_req will not get >>> updated. I >> >> I got your point now. >> >> My point is get_mode() should always return "correct" status by >> reading register value. >> And as you mentioned, regulator_set_mode() did check current mode and >> won't call >> set_mode callback if current mode is the same as the target mode. >> And that is why this patch won't work. >> >> However, Make get_mode() return "incorrect" status to avoid above >> issue looks wrong to me. >> >> Regards, >> Axel > > I understand your point of view, but I think that the framework (as it is > currently implemented) expects to get the requested mode of the regulator in > this case, not the actual mode (in the shared mode register).The alternative > could be to change the framework in some way. > > Any ideas? Otherwise I propose to keep the code and maybe add a comment. It looks to me a simple fix is to just get rid of the check of old mode with new mode setting. Something like reverse of commit 500b4ac90d1103 "regulator: return set_mode is same mode is requested" would work. Regards, Axel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/