From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Dr. Rainer Kaluscha" Subject: Re: [PATCH 1/2] regulator: add regulator_is_dummy function Date: Mon, 07 Jan 2013 13:30:54 +0100 Message-ID: <50EABFFE.9070908@web.de> References: <1357537131-8000-1-git-send-email-kliu5@marvell.com> <20130107112527.GD4544@opensource.wolfsonmicro.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from moutng.kundenserver.de ([212.227.126.186]:59131 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754416Ab3AGMa7 (ORCPT ); Mon, 7 Jan 2013 07:30:59 -0500 In-Reply-To: <20130107112527.GD4544@opensource.wolfsonmicro.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Mark Brown Cc: Kevin Liu , linux-pm@vger.kernel.org, linux-mmc@vger.kernel.org, Chris Ball , Marek Szyprowski , Rainer Kaluscha , Philip Rakity , Zhangfei Gao , Haojian Zhuang , Chao Xie , Kevin Liu Am 07.01.2013 12:25, schrieb Mark Brown: > On Mon, Jan 07, 2013 at 01:38:50PM +0800, Kevin Liu wrote: >> Introduce a regulator_is_dummy function to check whether the >> regulator is dummy. > > No, we've been through this repeatedly. Whatever problem you're trying > to bodge around is going to be a problem with some real physical > regulators too. Though I don't know the previous discussion, this seems a different case to me. The problem is that *only* a dummy regulator is available which refuses to do any regulation at all. So sdhci/mmc should better behave as no regulator was available at all. This may happen if e.g. in a precompiled kernel of some linux distro regulator support (including dummy) is enabled but the machine running that kernel doesn't have a known hardware regulator. This results in sdhci/mmc failing to enable the SD card reader though it would work well without regulator support in the kernel. Rainer