From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7F1AB8821; Fri, 29 Aug 2025 04:23:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756441406; cv=none; b=Zr7ss226axu2ZkPs0oAMs+SELm9/8/ElKLFTKaA88WWtZErCk684qZFqZz9n6/IgN4y60Olojx+8QF0j++1OJEeE1Zl3uOkF8CXhpcOdiY6G7upQeyIgupV5Xq/8z+OMgEOYpWUCb9p8+vySqT7Mu/QbIui+nzpXNOHxLSPyHyc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756441406; c=relaxed/simple; bh=T9LMVgGcKV1Pl4nv8nPVa+Y3TUkwZBT3XArHw1YhQwY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=f1Uw8Ngnc/qBTVB1jHlZROn2CQ6m1oSgi9sZMbsVlAWIRwWtZnHVYBIn13WInhYE4iAeAxK+/z141QiLGkQvP3nDPAi4mpgn0tpccSE1rhMDvGx1302J+P6Xj9sK2OaSAOmEsPTq1X1TJ4330ZxRC27WjFV306q9+FqQFYCHmu4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=uth4TT9R; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="uth4TT9R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BA3C9C4CEF0; Fri, 29 Aug 2025 04:23:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1756441406; bh=T9LMVgGcKV1Pl4nv8nPVa+Y3TUkwZBT3XArHw1YhQwY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=uth4TT9RMBqheGxNHOLlG+gah+0ELGAvawFgO39ue4OpAIt3wJ1u2KFCPRj4M0VqP cv/x8KmSe9bhItEL+/7Mu0hU8Uix2sEwJfbR/CemowOA8sJBdnBPoFTZs6zR4gUEDK rtIQ0KJ/KEB4pDrlvf2mifj0j+fTV/SfZ9B0FtkE= Date: Fri, 29 Aug 2025 06:23:22 +0200 From: Greg Kroah-Hartman To: =?iso-8859-1?Q?Jean-Fran=E7ois?= Lessard Cc: "Rafael J. Wysocki" , Danilo Krummrich , Andy Shevchenko , Daniel Scally , Heikki Krogerus , Sakari Ailus , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] device property: Add scoped fwnode child node iterators Message-ID: <2025082953-splendor-unsold-e4f2@gregkh> References: <20250829021802.16241-1-jefflessard3@gmail.com> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20250829021802.16241-1-jefflessard3@gmail.com> On Thu, Aug 28, 2025 at 10:17:59PM -0400, Jean-François Lessard wrote: > Add scoped versions of fwnode child node iterators that automatically > handle reference counting cleanup using the __free() attribute: > > - fwnode_for_each_child_node_scoped() > - fwnode_for_each_named_child_node_scoped() > - fwnode_for_each_available_child_node_scoped() > > These macros follow the same pattern as existing scoped iterators in the > kernel, ensuring fwnode references are automatically released when the > iterator variable goes out of scope. This prevents resource leaks and > eliminates the need for manual cleanup in error paths. > > The implementation mirrors the non-scoped variants but uses > __free(fwnode_handle) for automatic resource management, providing a safer > and more convenient interface for drivers iterating over firmware node > children. > > Signed-off-by: Jean-François Lessard > --- > > Notes: > checkpatch reports false positives that are intentionally ignored: > COMPLEX_MACRO, MACRO_ARG_REUSE, MACRO_ARG_PRECEDENCE > This is a standard iterator pattern following kernel conventions. > > include/linux/property.h | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/include/linux/property.h b/include/linux/property.h > index 82f0cb3ab..279c244db 100644 > --- a/include/linux/property.h > +++ b/include/linux/property.h > @@ -176,6 +176,20 @@ struct fwnode_handle *fwnode_get_next_available_child_node( > for (child = fwnode_get_next_available_child_node(fwnode, NULL); child;\ > child = fwnode_get_next_available_child_node(fwnode, child)) > > +#define fwnode_for_each_child_node_scoped(fwnode, child) \ > + for (struct fwnode_handle *child __free(fwnode_handle) = \ > + fwnode_get_next_child_node(fwnode, NULL); \ > + child; child = fwnode_get_next_child_node(fwnode, child)) > + > +#define fwnode_for_each_named_child_node_scoped(fwnode, child, name) \ > + fwnode_for_each_child_node_scoped(fwnode, child) \ > + for_each_if(fwnode_name_eq(child, name)) > + > +#define fwnode_for_each_available_child_node_scoped(fwnode, child) \ > + for (struct fwnode_handle *child __free(fwnode_handle) = \ > + fwnode_get_next_available_child_node(fwnode, NULL); \ > + child; child = fwnode_get_next_available_child_node(fwnode, child)) > + > struct fwnode_handle *device_get_next_child_node(const struct device *dev, > struct fwnode_handle *child); > We need a real user of this before we can add them, so please do that as part of a patch series. thanks greg k-h