(as my last comment was sufficiently explained and kinda forgot to add it) Acked-by: Crt Mori <cmo@xxxxxxxxxxx> On 23 October 2015 at 17:33, Daniel Baluta <daniel.baluta@xxxxxxxxx> wrote: > Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxxxx> > --- > Documentation/ABI/testing/configfs-iio | 21 ++++++++ > Documentation/iio/iio_configfs.txt | 93 ++++++++++++++++++++++++++++++++++ > 2 files changed, 114 insertions(+) > create mode 100644 Documentation/ABI/testing/configfs-iio > create mode 100644 Documentation/iio/iio_configfs.txt > > diff --git a/Documentation/ABI/testing/configfs-iio b/Documentation/ABI/testing/configfs-iio > new file mode 100644 > index 0000000..2483756 > --- /dev/null > +++ b/Documentation/ABI/testing/configfs-iio > @@ -0,0 +1,21 @@ > +What: /config/iio > +Date: October 2015 > +KernelVersion: 4.4 > +Contact: linux-iio@xxxxxxxxxxxxxxx > +Description: > + This represents Industrial IO configuration entry point > + directory. It contains sub-groups corresponding to IIO > + objects. > + > +What: /config/iio/triggers > +Date: October 2015 > +KernelVersion: 4.4 > +Description: > + Industrial IO software triggers directory. > + > +What: /config/iio/triggers/hrtimers > +Date: October 2015 > +KernelVersion: 4.4 > +Description: > + High resolution timers directory. Creating a directory here > + will result in creating a hrtimer trigger in the IIO subsystem. > diff --git a/Documentation/iio/iio_configfs.txt b/Documentation/iio/iio_configfs.txt > new file mode 100644 > index 0000000..f0add35 > --- /dev/null > +++ b/Documentation/iio/iio_configfs.txt > @@ -0,0 +1,93 @@ > +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/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 doesn't have any configurable attribute from /config dir. > +It does introduce the sampling_frequency attribute to trigger directory. > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html