From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9D9D3C55189 for ; Wed, 22 Apr 2020 11:58:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 874E42087E for ; Wed, 22 Apr 2020 11:58:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728051AbgDVL6G (ORCPT ); Wed, 22 Apr 2020 07:58:06 -0400 Received: from foss.arm.com ([217.140.110.172]:48294 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728052AbgDVL6F (ORCPT ); Wed, 22 Apr 2020 07:58:05 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0CE4531B; Wed, 22 Apr 2020 04:58:05 -0700 (PDT) Received: from e110455-lin.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C0BFB3F6CF; Wed, 22 Apr 2020 04:58:04 -0700 (PDT) Received: by e110455-lin.cambridge.arm.com (Postfix, from userid 1000) id 7871C682F37; Wed, 22 Apr 2020 12:58:03 +0100 (BST) Date: Wed, 22 Apr 2020 12:58:03 +0100 From: Liviu Dudau To: Rob Herring Cc: Linus Walleij , Lorenzo Pieralisi , Sudeep Holla , Arnd Bergmann , Catalin Marinas , Greg Kroah-Hartman , Lee Jones , Sebastian Reichel , Stephen Boyd , Will Deacon , Kevin Brodsky , linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org, linux-pm@vger.kernel.org Subject: Re: [PATCH 14/17] bus: vexpress-config: simplify config bus probing Message-ID: <20200422115803.GY364558@e110455-lin.cambridge.arm.com> References: <20200419170810.5738-1-robh@kernel.org> <20200419170810.5738-15-robh@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200419170810.5738-15-robh@kernel.org> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Sun, Apr 19, 2020 at 12:08:07PM -0500, Rob Herring wrote: > The vexpress-config initialization is dependent on the vexpress-syscfg > driver probing. As vexpress-config was not a driver, deferred probe > could not be used and instead initcall ordering was relied upon. This is > fragile and doesn't work for modules. > > Let's move the config bus init into the vexpress-syscfg probe. This > eliminates the initcall ordering requirement and the need to create a > struct device and the "vexpress-config" class. > > Cc: Liviu Dudau Acked-by: Liviu Dudau > Cc: Sudeep Holla > Cc: Lorenzo Pieralisi > Cc: Linus Walleij > Cc: Arnd Bergmann > Cc: Greg Kroah-Hartman > Signed-off-by: Rob Herring > --- > drivers/bus/vexpress-config.c | 118 ++++++---------------------------- > 1 file changed, 21 insertions(+), 97 deletions(-) > > diff --git a/drivers/bus/vexpress-config.c b/drivers/bus/vexpress-config.c > index 43f5beac9811..43deb4df140b 100644 > --- a/drivers/bus/vexpress-config.c > +++ b/drivers/bus/vexpress-config.c > @@ -56,7 +56,6 @@ struct vexpress_config_bridge { > > > static DEFINE_MUTEX(vexpress_config_mutex); > -static struct class *vexpress_config_class; > static u32 vexpress_config_site_master = VEXPRESS_SITE_MASTER; > > > @@ -121,9 +120,6 @@ struct regmap *devm_regmap_init_vexpress_config(struct device *dev) > struct regmap *regmap; > struct regmap **res; > > - if (WARN_ON(dev->parent->class != vexpress_config_class)) > - return ERR_PTR(-ENODEV); > - > bridge = dev_get_drvdata(dev->parent); > if (WARN_ON(!bridge)) > return ERR_PTR(-EINVAL); > @@ -146,94 +142,6 @@ struct regmap *devm_regmap_init_vexpress_config(struct device *dev) > } > EXPORT_SYMBOL_GPL(devm_regmap_init_vexpress_config); > > -static struct device *vexpress_config_bridge_register(struct device *parent, > - struct vexpress_config_bridge_ops *ops, void *context) > -{ > - struct device *dev; > - struct vexpress_config_bridge *bridge; > - > - if (!vexpress_config_class) { > - vexpress_config_class = class_create(THIS_MODULE, > - "vexpress-config"); > - if (IS_ERR(vexpress_config_class)) > - return (void *)vexpress_config_class; > - } > - > - dev = device_create(vexpress_config_class, parent, 0, > - NULL, "%s.bridge", dev_name(parent)); > - > - if (IS_ERR(dev)) > - return dev; > - > - bridge = devm_kmalloc(dev, sizeof(*bridge), GFP_KERNEL); > - if (!bridge) { > - put_device(dev); > - device_unregister(dev); > - return ERR_PTR(-ENOMEM); > - } > - bridge->ops = ops; > - bridge->context = context; > - > - dev_set_drvdata(dev, bridge); > - > - dev_dbg(parent, "Registered bridge '%s', parent node %p\n", > - dev_name(dev), parent->of_node); > - > - return dev; > -} > - > - > -static int vexpress_config_node_match(struct device *dev, const void *data) > -{ > - const struct device_node *node = data; > - > - dev_dbg(dev, "Parent node %p, looking for %p\n", > - dev->parent->of_node, node); > - > - return dev->parent->of_node == node; > -} > - > -static int vexpress_config_populate(struct device_node *node) > -{ > - struct device_node *bridge; > - struct device *parent; > - int ret; > - > - bridge = of_parse_phandle(node, "arm,vexpress,config-bridge", 0); > - if (!bridge) > - return -EINVAL; > - > - parent = class_find_device(vexpress_config_class, NULL, bridge, > - vexpress_config_node_match); > - of_node_put(bridge); > - if (WARN_ON(!parent)) > - return -ENODEV; > - > - ret = of_platform_populate(node, NULL, NULL, parent); > - > - put_device(parent); > - > - return ret; > -} > - > -static int __init vexpress_config_init(void) > -{ > - int err = 0; > - struct device_node *node; > - > - /* Need the config devices early, before the "normal" devices... */ > - for_each_compatible_node(node, NULL, "arm,vexpress,config-bus") { > - err = vexpress_config_populate(node); > - if (err) { > - of_node_put(node); > - break; > - } > - } > - > - return err; > -} > -postcore_initcall(vexpress_config_init); > - > static int vexpress_syscfg_exec(struct vexpress_syscfg_func *func, > int index, bool write, u32 *data) > { > @@ -430,7 +338,8 @@ static int vexpress_syscfg_probe(struct platform_device *pdev) > { > struct vexpress_syscfg *syscfg; > struct resource *res; > - struct device *bridge; > + struct vexpress_config_bridge *bridge; > + struct device_node *node; > > syscfg = devm_kzalloc(&pdev->dev, sizeof(*syscfg), GFP_KERNEL); > if (!syscfg) > @@ -443,11 +352,26 @@ static int vexpress_syscfg_probe(struct platform_device *pdev) > if (IS_ERR(syscfg->base)) > return PTR_ERR(syscfg->base); > > - /* Must use dev.parent (MFD), as that's where DT phandle points at... */ > - bridge = vexpress_config_bridge_register(pdev->dev.parent, > - &vexpress_syscfg_bridge_ops, syscfg); > + bridge = devm_kmalloc(&pdev->dev, sizeof(*bridge), GFP_KERNEL); > + if (!bridge) > + return -ENOMEM; > + > + bridge->ops = &vexpress_syscfg_bridge_ops; > + bridge->context = syscfg; > + > + dev_set_drvdata(&pdev->dev, bridge); > > - return PTR_ERR_OR_ZERO(bridge); > + for_each_compatible_node(node, NULL, "arm,vexpress,config-bus") { > + struct device_node *bridge_np; > + > + bridge_np = of_parse_phandle(node, "arm,vexpress,config-bridge", 0); > + if (bridge_np != pdev->dev.parent->of_node) > + continue; > + > + of_platform_populate(node, NULL, NULL, &pdev->dev); > + } > + > + return 0; > } > > static const struct platform_device_id vexpress_syscfg_id_table[] = { > -- > 2.20.1 > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯