Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760089Ab3HNQWE (ORCPT ); Wed, 14 Aug 2013 12:22:04 -0400 Received: from avon.wwwdotorg.org ([70.85.31.133]:60916 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760024Ab3HNQWB (ORCPT ); Wed, 14 Aug 2013 12:22:01 -0400 Message-ID: <520BAEA6.2070205@wwwdotorg.org> Date: Wed, 14 Aug 2013 10:21:58 -0600 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130803 Thunderbird/17.0.8 MIME-Version: 1.0 To: Linus Walleij CC: Sonic Zhang , Grant Likely , LKML , adi-buildroot-devel@lists.sourceforge.net, Sonic Zhang Subject: Re: [PATCH v4] pinctrl: pinmux: Don't free pins requested by other devices in pinmux_disable_setting. References: <1376458003-6244-1-git-send-email-sonic.adi@gmail.com> In-Reply-To: X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1477 Lines: 34 On 08/14/2013 09:54 AM, Linus Walleij wrote: > On Wed, Aug 14, 2013 at 7:26 AM, Sonic Zhang wrote: > >> From: Sonic Zhang >> >> One peripheral may share part of its pins with the 2nd >> peripheral and the other pins with the 3rd. If it requests all pins >> when part of them has already be requested and owned by the 2nd >> peripheral, this request fails and pinmux_disable_setting() is called. >> The pinmux_disable_setting() frees all pins of the first peripheral >> without checking if the pin is owned by itself or the 2nd, which >> results in the malfunction of the 2nd peripheral driver. >> >> Signed-off-by: Sonic Zhang > > Hm it makes some sense so patch applied. > > That said I think we currently have drivers where a pin group > mapped to a certain function in a certain setting *usually* > don't overlap with pins in another group used with another > function, and having it so seems racy, i.e. it will be some > first-come-first-serve effect. > > I will add a warning print. Surely there's a warning print already when the enable_setting() fails, so we don't need to do any more warning prints when the free_setting() cleans up after that? -- 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/