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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 EF34FC4361B for ; Sun, 6 Dec 2020 07:49:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD260230FA for ; Sun, 6 Dec 2020 07:49:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725800AbgLFHtZ (ORCPT ); Sun, 6 Dec 2020 02:49:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:57384 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725613AbgLFHtZ (ORCPT ); Sun, 6 Dec 2020 02:49:25 -0500 Date: Sun, 6 Dec 2020 09:48:40 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1607240924; bh=9RVRjkcvVquBMHyd3Wc3YEmznoMGzbtr/AV76Fx0Tz8=; h=From:To:Cc:Subject:References:In-Reply-To:From; b=cTxMmt4twoBw6wAl3BBQFHmmQfMShJO0R/dgxuZ6/6p2g1hsRUuNd3q2Zeu186GBQ IU4tNhTvARUxceZ7XeE55FxFaez+KWXQ55L/xnTYj58sdYAxvX2MeT9aqZcbwePXEV 1yzrpblL7yjIuyLbr9Yb/Uba5iojEuxUFIuddXoXDVZZ03+Khre/SjqiPgXW980nEY npQOWuImlR1AQjGBYQkM1FaIzGcJz+AQH8yxvf1cLOvVNuDHzTL+Zf2dfxC3F1sB3u ZEOWOfAhoHWFajTAAPCRhdO/8bBuH78eXFOLLCwZ720bbg7qImONlmmj61hC3w/vlf 2mBqqSU3GLGbA== From: Leon Romanovsky To: Saravana Kannan Cc: "Rafael J. Wysocki" , "Rafael J. Wysocki" , Len Brown , Greg Kroah-Hartman , Ard Biesheuvel , Rob Herring , Frank Rowand , Marc Zyngier , Thomas Gleixner , Tomi Valkeinen , Laurent Pinchart , Grygorii Strashko , kernel-team@android.com, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, devicetree@vger.kernel.org Subject: Re: [PATCH v2 08/17] driver core: Add fwnode link support Message-ID: <20201206074840.GB687065@unreal> References: <20201121020232.908850-1-saravanak@google.com> <20201121020232.908850-9-saravanak@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201121020232.908850-9-saravanak@google.com> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Fri, Nov 20, 2020 at 06:02:23PM -0800, Saravana Kannan wrote: > Add support for creating supplier-consumer links between fwnodes. It is > intended for internal use the driver core and generic firmware support > code (eg. Device Tree, ACPI), so it is simple by design and the API > provided is limited. > > Signed-off-by: Saravana Kannan > --- > drivers/base/core.c | 98 ++++++++++++++++++++++++++++++++++++++++++ > drivers/of/dynamic.c | 1 + > include/linux/fwnode.h | 14 ++++++ > 3 files changed, 113 insertions(+) > > diff --git a/drivers/base/core.c b/drivers/base/core.c > index 401fa7e3505c..e2b246a44d1a 100644 > --- a/drivers/base/core.c > +++ b/drivers/base/core.c > @@ -50,6 +50,104 @@ static LIST_HEAD(wait_for_suppliers); > static DEFINE_MUTEX(wfs_lock); > static LIST_HEAD(deferred_sync); > static unsigned int defer_sync_state_count = 1; > +static DEFINE_MUTEX(fwnode_link_lock); > + > +/** > + * fwnode_link_add - Create a link between two fwnode_handles. > + * @con: Consumer end of the link. > + * @sup: Supplier end of the link. > + * > + * Create a fwnode link between fwnode handles @con and @sup. The fwnode link > + * represents the detail that the firmware lists @sup fwnode as supplying a > + * resource to @con. > + * > + * The driver core will use the fwnode link to create a device link between the > + * two device objects corresponding to @con and @sup when they are created. The > + * driver core will automatically delete the fwnode link between @con and @sup > + * after doing that. > + * > + * Attempts to create duplicate links between the same pair of fwnode handles > + * are ignored and there is no reference counting. Sorry to ask, but why is that? Isn't this a programmer error? Thanks