From patchwork Tue Apr 9 23:22:01 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Kevin Hilman X-Patchwork-Id: 2418311 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id D8D603FC71 for ; Tue, 9 Apr 2013 23:22:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756358Ab3DIXWI (ORCPT ); Tue, 9 Apr 2013 19:22:08 -0400 Received: from mail-pd0-f176.google.com ([209.85.192.176]:40092 "EHLO mail-pd0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760052Ab3DIXWG (ORCPT ); Tue, 9 Apr 2013 19:22:06 -0400 Received: by mail-pd0-f176.google.com with SMTP id r11so3972277pdi.35 for ; Tue, 09 Apr 2013 16:22:04 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-received:from:to:cc:subject:date:message-id:x-mailer:mime-version :content-type:content-transfer-encoding:x-gm-message-state; bh=an+RVTGH9bZnbpzvvl4asypt6qADSzRKU00zR6Dutj0=; b=IwkHCzdYtMmUQx130FooI4FZOvb7cB2G69NaFEkJU02TeNb39oMXHA9mzmeu97gLF1 8YNHpXfnCwnxYHSl7BeJk/nxyQ3Z2af/o2UwJSIfimr95h9rFy7V+FOGu7f5tY+IL1OI /4oWud7O8GnRHMdscSFD/TdGxgot+ci3lO4AHSCu2eL05bVJWmCWyec72/RjDsEvJEcV MyoT+eQmHTpP+DAEDsaWw1aizYOkK/gcmGWzIkS+4QeF2pMDqug5VrIwMyW2sDHmHbMM 5nfB7NM7sxuSfSWtuR8qSCg83UWmrAxN3XQKcoL7Lb6rvyURQVJEL/bZ8Ds1RkJEmfRg T1fg== X-Received: by 10.68.17.230 with SMTP id r6mr4916310pbd.187.1365549724654; Tue, 09 Apr 2013 16:22:04 -0700 (PDT) Received: from localhost (c-24-19-7-36.hsd1.wa.comcast.net. [24.19.7.36]) by mx.google.com with ESMTPS id yr10sm48303247pab.6.2013.04.09.16.22.02 (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Tue, 09 Apr 2013 16:22:03 -0700 (PDT) From: Kevin Hilman To: "Rafael J. Wysocki" Cc: linux-pm@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Nishanth Menon Subject: [PATCH] cpufreq: OMAP: instantiate omap-cpufreq as a platform_driver Date: Tue, 9 Apr 2013 16:22:01 -0700 Message-Id: <1365549721-15620-1-git-send-email-khilman@linaro.org> X-Mailer: git-send-email 1.8.2 MIME-Version: 1.0 X-Gm-Message-State: ALoCoQlKmoEJP/P5XUsW1eeKL+CHNbRGudrpeNpiqfW4dNC+kPWl8ZCWY1KnXPBavnXaGDYGt9yY Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org From: Nishanth Menon As multi-platform build is being adopted by more and more ARM platforms, initcall function should be used very carefully. For example, when CONFIG_ARM_OMAP2PLUS_CPUFREQ is built in the kernel, omap_cpufreq_init() will be called on all the platforms to initialize omap-cpufreq driver. Further, on OMAP, we now use Soc generic cpufreq-cpu0 driver using device tree entries. To allow cpufreq-cpu0 and omap-cpufreq drivers to co-exist for OMAP in a single image, we need to ensure the following: 1. With device tree boot, we use cpufreq-cpu0 2. With non device tree boot, we use omap-cpufreq In the case of (1), we will have cpu OPPs and regulator registered as part of the device tree nodes, to ensure that omap-cpufreq and cpufreq-cpu0 don't conflict in managing the frequency of the same CPU, we should not permit omap-cpufreq to be probed. In the case of (2), we will not have the cpufreq-cpu0 device, hence only omap-cpufreq will be active. To eliminate this undesired these effects, we change omap-cpufreq driver to have it instantiated as a platform_driver and register "omap-cpufreq" device only when booted without device tree nodes on OMAP platforms. This allows the following: a) Will only run on platforms that create the platform_device "omap-cpufreq". b) Since the platform_device is registered only when device tree nodes are *not* populated, omap-cpufreq driver does not conflict with the usage of cpufreq-cpu0 driver which is used on OMAP platforms when device tree nodes are present. Inspired by commit 5553f9e26f6f49a93ba732fd222eac6973a4cf35 (cpufreq: instantiate cpufreq-cpu0 as a platform_driver) Cc: Kevin Hilman Cc: Rajendra Nayak Cc: Paul Walmsley Cc: "Benoît Cousson" Cc: Jon Hunter Cc: Keerthy Cc: Santosh Shilimkar Cc: Shawn Guo [robherring2@gmail.com: reported conflict of omap-cpufreq vs other driver in an non-device tree supported boot] Reported-by: Rob Herring Signed-off-by: Nishanth Menon Acked-by: Viresh Kumar Signed-off-by: Kevin Hilman --- Rafael, can you add this one for v3.10? It applies on top the rest of your cpufreq changes and I've verified that the OMAP changes are OK and don't conflict with anything else we have queued for v3.10 on OMAP. This patch was previously part of a 2-patch series, but the other part is still in discussion, and this part can be merged independently. arch/arm/mach-omap2/pm.c | 9 +++++++++ drivers/cpufreq/omap-cpufreq.c | 19 ++++++++++++++----- 2 files changed, 23 insertions(+), 5 deletions(-) diff --git a/arch/arm/mach-omap2/pm.c b/arch/arm/mach-omap2/pm.c index 673a4c1..8d15f9a 100644 --- a/arch/arm/mach-omap2/pm.c +++ b/arch/arm/mach-omap2/pm.c @@ -265,6 +265,12 @@ static void __init omap4_init_voltages(void) omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva"); } +static inline void omap_init_cpufreq(void) +{ + struct platform_device_info devinfo = { .name = "omap-cpufreq", }; + platform_device_register_full(&devinfo); +} + static int __init omap2_common_pm_init(void) { if (!of_have_populated_dt()) @@ -294,6 +300,9 @@ int __init omap2_common_pm_late_init(void) /* Smartreflex device init */ omap_devinit_smartreflex(); + + /* cpufreq dummy device instantiation */ + omap_init_cpufreq(); } #ifdef CONFIG_SUSPEND diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c index 9128c07..d4f84b8 100644 --- a/drivers/cpufreq/omap-cpufreq.c +++ b/drivers/cpufreq/omap-cpufreq.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include @@ -252,7 +253,7 @@ static struct cpufreq_driver omap_driver = { .attr = omap_cpufreq_attr, }; -static int __init omap_cpufreq_init(void) +static int omap_cpufreq_probe(struct platform_device *pdev) { mpu_dev = get_cpu_device(0); if (!mpu_dev) { @@ -280,12 +281,20 @@ static int __init omap_cpufreq_init(void) return cpufreq_register_driver(&omap_driver); } -static void __exit omap_cpufreq_exit(void) +static int omap_cpufreq_remove(struct platform_device *pdev) { - cpufreq_unregister_driver(&omap_driver); + return cpufreq_unregister_driver(&omap_driver); } +static struct platform_driver omap_cpufreq_platdrv = { + .driver = { + .name = "omap-cpufreq", + .owner = THIS_MODULE, + }, + .probe = omap_cpufreq_probe, + .remove = omap_cpufreq_remove, +}; +module_platform_driver(omap_cpufreq_platdrv); + MODULE_DESCRIPTION("cpufreq driver for OMAP SoCs"); MODULE_LICENSE("GPL"); -module_init(omap_cpufreq_init); -module_exit(omap_cpufreq_exit);