From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-13.3 required=5.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_NONE, USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id D76187D913 for ; Thu, 29 Aug 2019 07:46:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728068AbfH2Hqh (ORCPT ); Thu, 29 Aug 2019 03:46:37 -0400 Received: from mail-pf1-f202.google.com ([209.85.210.202]:49762 "EHLO mail-pf1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728053AbfH2Hqc (ORCPT ); Thu, 29 Aug 2019 03:46:32 -0400 Received: by mail-pf1-f202.google.com with SMTP id s10so1834286pfd.16 for ; Thu, 29 Aug 2019 00:46:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=nhjHwCHt3mcz+mHDiVxN7s8L1KuUZ7MDwDAfLe16I50=; b=G+4eBBbE8eR+JweFO/MTbU/JiiK//ZmQj8k/LyrXbCGTThb38w/Z2lUm+J9+GnNM0R ILZAbYqpRKL7TOIZvfQiUJ2cF39/iD9rfGRzN/JPmUP0imOiTAzvaNMocnkNuQkRpez1 TeFD7m5SShMLKZ99sCn6+3Jk0GWByzZ/IZjTTkJhmHdk/U8KSb8jext129vtnUphdVPK 3Og8DoR1JhhS8QHP8PSei9z2OIoEIJgw7WByG4I5s8EIdtWDrfnC1s2xxQI7P6I0R2oo vZCWREqieybOCkNKb7WgvgWuO6NUQORyGlcpSxF+myfSq3RilEg/tbt3CAbeESXosLmc vLfQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=nhjHwCHt3mcz+mHDiVxN7s8L1KuUZ7MDwDAfLe16I50=; b=ICYFZNme7OTNpQaFr/175D9cYT/q351qyJxv0fh2J12zIQtaePlwEUVF1MihB2GDQ8 qLeSbZPlKWpWSnGw0gFzmmWdBAjD9BVBwsyhlWlHiCGzPWPYatdnUeHy+Yn8PSSvf3/5 9MUpuZtAIGnXfGOuiU4pr2KmKOiGVJteMl4Fs52vdai11L2xNvpwc5qKdAYezbohuOIa qgOLUq+XhthRJkOFpyE7PTnAQSQz/vyrM8lbMs3Z4JTkXlJ2VQ9PvDmg1T3zvVO/XlTr nTDd0ETBJbDTmLd2bPcuDLAHyWfzUp5reWBUIAwiZJPOBfpyfAft3HvdR1qLR435+ccP 7yVw== X-Gm-Message-State: APjAAAUThWHZ03nKmyVkNBuLgpUemDNhyT8x5G3Mngm6NaU8rUzj66Pv lve8H3G8wHu4onyZpATtw4T2rZyr6Ce9H0s= X-Google-Smtp-Source: APXvYqxjRrI7v0tAcH4lDhIBqUhl0wBMcJY40NePOKQ5MWBcbB/tbpokA1E16lgkYG8HCTLquA1Ns3qi+HNbWZE= X-Received: by 2002:a65:690f:: with SMTP id s15mr6855732pgq.432.1567064791199; Thu, 29 Aug 2019 00:46:31 -0700 (PDT) Date: Thu, 29 Aug 2019 00:46:03 -0700 In-Reply-To: <20190829074603.70424-1-saravanak@google.com> Message-Id: <20190829074603.70424-8-saravanak@google.com> Mime-Version: 1.0 References: <20190829074603.70424-1-saravanak@google.com> X-Mailer: git-send-email 2.23.0.187.g17f5b7556c-goog Subject: [PATCH v10 7/7] of: property: Add "depends-on" parsing support to of_fwnode_add_links() From: Saravana Kannan To: Rob Herring , Mark Rutland , Greg Kroah-Hartman , "Rafael J. Wysocki" , Frank Rowand , Jonathan Corbet , Len Brown Cc: Saravana Kannan , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-acpi@vger.kernel.org, clang-built-linux@googlegroups.com, David Collins , kernel-team@android.com Content-Type: text/plain; charset="UTF-8" Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org If dependencies inferred by of_fwnode_add_links() result in a cycle, it can prevent the probing of all the devices in the cycle. The depends-on property has been added to explicitly override inferred dependencies when they create a cycle. Add depends-on parsing support to of_fwnode_add_links() so that platforms with cyclic dependencies can use "depends-on" to break the cycle and continue successfully probing devices. Signed-off-by: Saravana Kannan --- drivers/of/property.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/of/property.c b/drivers/of/property.c index 420c2d428184..78a262e24686 100644 --- a/drivers/of/property.c +++ b/drivers/of/property.c @@ -1106,6 +1106,12 @@ static struct device_node *parse_interconnects(struct device_node *np, "#interconnect-cells"); } +static struct device_node *parse_depends_on(struct device_node *np, + const char *prop_name, int index) +{ + return parse_prop_cells(np, prop_name, index, "depends-on", NULL); +} + static int strcmp_suffix(const char *str, const char *suffix) { unsigned int len, suffix_len; @@ -1151,6 +1157,7 @@ static const struct supplier_bindings bindings[] = { { .parse_prop = parse_clocks, }, { .parse_prop = parse_interconnects, }, { .parse_prop = parse_regulators, }, + { .parse_prop = parse_depends_on, }, {}, }; @@ -1203,6 +1210,12 @@ static int __of_link_to_suppliers(struct device *dev, struct property *p; int ret = 0; + if (of_find_property(con_np, "depends-on", NULL)) { + if (of_link_property(dev, con_np, "depends-on")) + ret = -EAGAIN; + return ret; + } + for_each_property_of_node(con_np, p) if (of_link_property(dev, con_np, p->name)) ret = -EAGAIN; -- 2.23.0.187.g17f5b7556c-goog