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: 9231493 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 686DE608A6 for ; Fri, 15 Jul 2016 10:03:13 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 580D027CCB for ; Fri, 15 Jul 2016 10:03:13 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 466E12832D; Fri, 15 Jul 2016 10:03:13 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id CF13F2819A for ; Fri, 15 Jul 2016 10:03:12 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bNzwN-0004ZS-5t; Fri, 15 Jul 2016 10:01:51 +0000 Received: from down.free-electrons.com ([37.187.137.238] helo=mail.free-electrons.com) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bNzw6-0004BG-MY for linux-arm-kernel@lists.infradead.org; Fri, 15 Jul 2016 10:01:36 +0000 Received: by mail.free-electrons.com (Postfix, from userid 110) id CD1EB420; Fri, 15 Jul 2016 12:01:17 +0200 (CEST) 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 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> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160715_030134_977634_B6942673 X-CRM114-Status: GOOD ( 11.08 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-hwmon@vger.kernel.org, thomas.petazzoni@free-electrons.com, linux-iio@vger.kernel.org, antoine.tenart@free-electrons.com, linux-kernel@vger.kernel.org, Quentin Schulz , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP 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(-) 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) {