Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932750Ab3HNQ2A (ORCPT ); Wed, 14 Aug 2013 12:28:00 -0400 Received: from mail-ob0-f175.google.com ([209.85.214.175]:44007 "EHLO mail-ob0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932352Ab3HNQ17 (ORCPT ); Wed, 14 Aug 2013 12:27:59 -0400 MIME-Version: 1.0 In-Reply-To: <520BAEA6.2070205@wwwdotorg.org> References: <1376458003-6244-1-git-send-email-sonic.adi@gmail.com> <520BAEA6.2070205@wwwdotorg.org> Date: Wed, 14 Aug 2013 18:27:58 +0200 Message-ID: Subject: Re: [PATCH v4] pinctrl: pinmux: Don't free pins requested by other devices in pinmux_disable_setting. From: Linus Walleij To: Stephen Warren Cc: Sonic Zhang , Grant Likely , LKML , adi-buildroot-devel@lists.sourceforge.net, Sonic Zhang Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1760 Lines: 41 On Wed, Aug 14, 2013 at 6:21 PM, Stephen Warren wrote: > 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? Now I'm confused ... I added debug prints to pinmux_disable_setting() which is where the patch hits? free_setting() is just an empty function body still. Yours, Linus Walleij -- 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/