From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: 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 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> 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-hwmon-owner@vger.kernel.org List-Id: linux-hwmon@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(-) 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) { -- 2.5.0 From mboxrd@z Thu Jan 1 00:00:00 1970 From: quentin.schulz@free-electrons.com (Quentin Schulz) Date: Fri, 15 Jul 2016 11:59:11 +0200 Subject: [PATCH v2 1/4] hwmon: iio_hwmon: defer probe when no channel is found 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> Message-ID: <1468576754-3273-2-git-send-email-quentin.schulz@free-electrons.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.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(-) 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) { -- 2.5.0