Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755549AbbDTOBc (ORCPT ); Mon, 20 Apr 2015 10:01:32 -0400 Received: from mga14.intel.com ([192.55.52.115]:28322 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755294AbbDTOBT (ORCPT ); Mon, 20 Apr 2015 10:01:19 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,609,1422950400"; d="scan'208";a="682778594" From: Daniel Baluta To: jic23@kernel.org Cc: jlbec@evilplan.org, lars@metafoo.de, knaack.h@gmx.de, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, octavian.purdila@intel.com, pebolle@tiscali.nl, patrick.porlan@intel.com, adriana.reus@intel.com, constantin.musca@intel.com, marten@intuitiveaerial.com Subject: [PATCH v4 4/4] iio: Documentation: Add IIO configfs documentation Date: Mon, 20 Apr 2015 17:02:43 +0300 Message-Id: <1429538563-23430-5-git-send-email-daniel.baluta@intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1429538563-23430-1-git-send-email-daniel.baluta@intel.com> References: <1429538563-23430-1-git-send-email-daniel.baluta@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2729 Lines: 87 Signed-off-by: Daniel Baluta --- Documentation/iio/iio_configfs.txt | 67 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 Documentation/iio/iio_configfs.txt diff --git a/Documentation/iio/iio_configfs.txt b/Documentation/iio/iio_configfs.txt new file mode 100644 index 0000000..1aa66d1 --- /dev/null +++ b/Documentation/iio/iio_configfs.txt @@ -0,0 +1,67 @@ +Industrial IIO configfs support + +1. Overview + +Configfs is a filesystem-based manager of kernel objects. IIO uses some +objects that could be easily configured using configfs (e.g.: devices, +triggers). + +See Documentation/filesystems/configfs/configfs.txt for more information +about how configfs works. + +2. Usage + +In order to use configfs support in IIO we need to select it at compile +time via CONFIG_IIO_CONFIGFS config option. + +Then, mount the configfs filesystem (usually under /config directory): + +$ mkdir /config +$ mount -t configfs none /config + +At this point, all default IIO groups will be created and can be accessed +under /config/iio. Next chapters will describe available IIO configuration +objects. + +3. Software triggers + +One of the IIO default configfs groups is the "triggers" groups. It is +automagically accessible when the configfs is mounted and can be found +under /config/iio/triggers. + +Software triggers are created under /config/iio/triggers directory. A sofware +trigger name MUST be of the following form: + * -: +Where: + * , specifies the interrupt source (e.g: hrtimer) + * , spefcifies the IIO device trigger name + +We support now to following interrupt sources (trigger types): + * hrtimer, uses high resolution timers as interrupt source + +3.1 Software triggers creation and destruction + +As simply as: + +$ mkdir /config/triggers/- +$ rmdir /config/triggers/- +e.g: + +$ mkdir /config/triggers/hrtimer-instance1 +$ rmdir /config/triggers/hrtimer-instance1 + +Each trigger can have one or more attributes specific to the trigger type. + +3.2 "hrtimer" trigger types attributes + +"hrtimer" trigger type has only one attribute: + +$ ls /config/triggers/hrtimer-instance1 +sampling_frequency + +sampling_frequency - represents the period in Hz between two consecutive +iio_trigger_poll calls. By default it is set to 100Hz. + +4. Further work + +* add "sysfs" trigger type -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/