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Diffstat (limited to 'Documentation/iio/iio_configfs.txt')
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diff --git a/Documentation/iio/iio_configfs.txt b/Documentation/iio/iio_configfs.txt deleted file mode 100644 index 4e5f101837a8..000000000000 --- a/Documentation/iio/iio_configfs.txt +++ /dev/null @@ -1,93 +0,0 @@ -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" group. It is -automagically accessible when the configfs is mounted and can be found -under /config/iio/triggers. - -IIO software triggers implementation offers support for creating multiple -trigger types. A new trigger type is usually implemented as a separate -kernel module following the interface in include/linux/iio/sw_trigger.h: - -/* - * drivers/iio/trigger/iio-trig-sample.c - * sample kernel module implementing a new trigger type - */ -#include <linux/iio/sw_trigger.h> - - -static struct iio_sw_trigger *iio_trig_sample_probe(const char *name) -{ - /* - * This allocates and registers an IIO trigger plus other - * trigger type specific initialization. - */ -} - -static int iio_trig_hrtimer_remove(struct iio_sw_trigger *swt) -{ - /* - * This undoes the actions in iio_trig_sample_probe - */ -} - -static const struct iio_sw_trigger_ops iio_trig_sample_ops = { - .probe = iio_trig_sample_probe, - .remove = iio_trig_sample_remove, -}; - -static struct iio_sw_trigger_type iio_trig_sample = { - .name = "trig-sample", - .owner = THIS_MODULE, - .ops = &iio_trig_sample_ops, -}; - -module_iio_sw_trigger_driver(iio_trig_sample); - -Each trigger type has its own directory under /config/iio/triggers. Loading -iio-trig-sample module will create 'trig-sample' trigger type directory -/config/iio/triggers/trig-sample. - -We support the following interrupt sources (trigger types): - * hrtimer, uses high resolution timers as interrupt source - -3.1 Hrtimer triggers creation and destruction - -Loading iio-trig-hrtimer module will register hrtimer trigger types allowing -users to create hrtimer triggers under /config/iio/triggers/hrtimer. - -e.g: - -$ mkdir /config/iio/triggers/hrtimer/instance1 -$ rmdir /config/iio/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 doesn't have any configurable attribute from /config dir. -It does introduce the sampling_frequency attribute to trigger directory. |