Staging: IIO: Trigger support added to core.

Add general registration support for IIO triggers.  These
are currently only used to initialize a 'poll' of a given
device.  Examples include the lis3l02dq's data ready signal
being used to initialize a read and gpio triggers being
used to allow externally synchronized sensor reading.

Each trigger can cause any number of 'consumer' devices
to be polled with each storing data into a related ring
buffer.

Two stage triggering is supported with 'fast' and 'slow'
paths.  The first is used for things like pulling a data
hold line high and the second for actual read which
may take far longer.

Changes since V2:
* As with IIO triggers now use a registration approach
  much closer to that of input leading to cleaner code.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 20 insertions, 1 deletions

diff --git a/drivers/staging/iio/trigger_consumer.h b/drivers/staging/iio/trigger_consumer.h
index a6053892893f..4c7f527dc79f 100644
--- a/drivers/staging/iio/trigger_consumer.h
+++ b/drivers/staging/iio/trigger_consumer.h
@@ -8,6 +8,20 @@
  * the Free Software Foundation.
  */
 
+#ifdef CONFIG_IIO_TRIGGER
+/**
+ * iio_device_register_trigger_consumer() - set up an iio_dev to use triggers.
+ * @dev_info: iio_dev associated with the device that will consume the trigger
+ **/
+int iio_device_register_trigger_consumer(struct iio_dev *dev_info);
+/**
+ * iio_device_unregister_trigger_consumer() - reverse the registration process.
+ * @dev_info: iio_dev associated with the device that consumed the trigger
+ **/
+int iio_device_unregister_trigger_consumer(struct iio_dev *dev_info);
+
+#else
+
 /**
  * iio_device_register_trigger_consumer() - set up an iio_dev to use triggers.
  * @dev_info: iio_dev associated with the device that will consume the trigger
@@ -18,9 +32,14 @@ int iio_device_register_trigger_consumer(struct iio_dev *dev_info)
 };
 /**
  * iio_device_unregister_trigger_consumer() - reverse the registration process
-. * @dev_info: iio_dev associated with the device that consumed the trigger
+ * @dev_info: iio_dev associated with the device that consumed the trigger
  **/
 int iio_device_unregister_trigger_consumer(struct iio_dev *dev_info)
 {
 	return 0;
 };
+
+#endif /* CONFIG_TRIGGER_CONSUMER */
+
+
+