From patchwork Mon Feb 8 21:02:48 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 44858 X-Patchwork-Delegate: grant.likely@secretlab.ca Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from bilbo.ozlabs.org (localhost [127.0.0.1]) by ozlabs.org (Postfix) with ESMTP id ADB5FB7F91 for ; Tue, 9 Feb 2010 08:03:22 +1100 (EST) Received: by ozlabs.org (Postfix) id 570A8B7CEF; Tue, 9 Feb 2010 08:03:15 +1100 (EST) Delivered-To: linuxppc-dev@ozlabs.org Received: from smtp1.linux-foundation.org (smtp1.linux-foundation.org [140.211.169.13]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "smtp.linux-foundation.org", Issuer "CA Cert Signing Authority" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id F1B27B7CBB for ; Tue, 9 Feb 2010 08:03:14 +1100 (EST) Received: from imap1.linux-foundation.org (imap1.linux-foundation.org [140.211.169.55]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id o18L2nHT014894 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Mon, 8 Feb 2010 13:02:50 -0800 Received: from akpm.mtv.corp.google.com (localhost [127.0.0.1]) by imap1.linux-foundation.org (8.13.5.20060308/8.13.5/Debian-3ubuntu1.1) with SMTP id o18L2mP7002787; Mon, 8 Feb 2010 13:02:48 -0800 Date: Mon, 8 Feb 2010 13:02:48 -0800 From: Andrew Morton To: Anton Vorontsov Subject: Re: [PATCH 3/4] of/gpio: Implement GPIOLIB notifier hooks Message-Id: <20100208130248.72febd68.akpm@linux-foundation.org> In-Reply-To: <20100205203236.GC1475@oksana.dev.rtsoft.ru> References: <20100205203201.GA32281@oksana.dev.rtsoft.ru> <20100205203236.GC1475@oksana.dev.rtsoft.ru> X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.9; x86_64-pc-linux-gnu) Mime-Version: 1.0 X-Spam-Status: No, hits=-3.519 required=5 tests=AWL, BAYES_00, OSDL_HEADER_SUBJECT_BRACKETED X-Spam-Checker-Version: SpamAssassin 3.2.4-osdl_revision__1.47__ X-MIMEDefang-Filter: lf$Revision: 1.188 $ X-Scanned-By: MIMEDefang 2.63 on 140.211.169.13 Cc: David Brownell , Dmitry Eremin-Solenikov , linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Bill Gatliff X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org On Fri, 5 Feb 2010 23:32:36 +0300 Anton Vorontsov wrote: > This patch implements GPIOLIB notifier hooks, and thus makes device-enabled > GPIO chips (i.e. the ones that have gpio_chip->dev specified) automatically > attached to the OpenFirmware subsystem. Which means that now we can handle > I2C and SPI GPIO chips almost* transparently. > > * "Almost" because some chips still require platform data, and for these > chips OF-glue is still needed, though with this support the glue will > be much smaller. > We can clean this up a little with the WARN_ON trick: diff -puN drivers/of/gpio.c~of-gpio-implement-gpiolib-notifier-hooks-fix drivers/of/gpio.c --- a/drivers/of/gpio.c~of-gpio-implement-gpiolib-notifier-hooks-fix +++ a/drivers/of/gpio.c @@ -255,10 +255,8 @@ static int of_gpiochip_register_simple(s { struct of_gpio_chip *of_gc; - if (np->data) { - WARN_ON(1); + if (WARN_ON(np->data)) return -EBUSY; - } of_gc = kzalloc(sizeof(*of_gc), GFP_KERNEL); if (!of_gc) @@ -287,10 +285,8 @@ static int of_gpiochip_unregister(struct { struct of_gpio_chip *of_gc = np->data; - if (!of_gc || of_gc->chip != chip) { - WARN_ON(1); + if (WARN_ON(!of_gc || of_gc->chip != chip)) return -EINVAL; - } np->data = NULL; kfree(of_gc);