From patchwork Fri Jul 15 09:59:11 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Quentin Schulz X-Patchwork-Id: 72080 Delivered-To: patch@linaro.org Received: by 10.140.29.52 with SMTP id a49csp526963qga; Fri, 15 Jul 2016 03:01:36 -0700 (PDT) X-Received: by 10.67.5.33 with SMTP id cj1mr30263932pad.50.1468576896449; Fri, 15 Jul 2016 03:01:36 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id ye8si8413292pab.169.2016.07.15.03.01.36; Fri, 15 Jul 2016 03:01:36 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932348AbcGOKBW (ORCPT + 29 others); Fri, 15 Jul 2016 06:01:22 -0400 Received: from down.free-electrons.com ([37.187.137.238]:43813 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752921AbcGOKBT (ORCPT ); Fri, 15 Jul 2016 06:01:19 -0400 Received: by mail.free-electrons.com (Postfix, from userid 110) id CD1EB420; Fri, 15 Jul 2016 12:01:17 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on mail.free-electrons.com X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,SHORTCIRCUIT, URIBL_BLOCKED shortcircuit=ham autolearn=disabled version=3.4.0 Received: from localhost.localdomain (lan31-h06-87-91-62-133.dsl.sta.abo.bbox.fr [87.91.62.133]) by mail.free-electrons.com (Postfix) with ESMTPSA id 032953D9; Fri, 15 Jul 2016 12:01:06 +0200 (CEST) From: Quentin Schulz To: jdelvare@suse.com, linux@roeck-us.net, jic23@kernel.org, knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, maxime.ripard@free-electrons.com, wens@csie.org, lee.jones@linaro.org Cc: Quentin Schulz , linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-iio@vger.kernel.org, linux-arm-kernel@lists.infradead.org, thomas.petazzoni@free-electrons.com, antoine.tenart@free-electrons.com Subject: [PATCH v2 1/4] hwmon: iio_hwmon: defer probe when no channel is found Date: Fri, 15 Jul 2016 11:59:11 +0200 Message-Id: <1468576754-3273-2-git-send-email-quentin.schulz@free-electrons.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1468576754-3273-1-git-send-email-quentin.schulz@free-electrons.com> References: <1468576754-3273-1-git-send-email-quentin.schulz@free-electrons.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org iio_channel_get_all returns -ENODEV when it cannot find either phandles and properties in the Device Tree or channels whose consumer_dev_name matches iio_hwmon in iio_map_list. The iio_map_list is filled in by iio drivers which might be probed after iio_hwmon. It is better to defer the probe of iio_hwmon if such error is returned by iio_channel_get_all in order to let a chance to iio drivers to expose channels in iio_map_list. Signed-off-by: Quentin Schulz --- No modifications for this patch since we did not settled for a solution. What should we do? drivers/hwmon/iio_hwmon.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) -- 2.5.0 diff --git a/drivers/hwmon/iio_hwmon.c b/drivers/hwmon/iio_hwmon.c index b550ba5..c0da4d9 100644 --- a/drivers/hwmon/iio_hwmon.c +++ b/drivers/hwmon/iio_hwmon.c @@ -73,8 +73,11 @@ static int iio_hwmon_probe(struct platform_device *pdev) name = dev->of_node->name; channels = iio_channel_get_all(dev); - if (IS_ERR(channels)) + if (IS_ERR(channels)) { + if (PTR_ERR(channels) == -ENODEV) + return -EPROBE_DEFER; return PTR_ERR(channels); + } st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL); if (st == NULL) {