iio:trigger: Add helper function to verify that a trigger belongs to the same device

Some triggers can only be attached to the IIO device that corresponds to
the same physical device. Currently each driver that requires this
implements its own trigger validation function.

Introduce a new helper function called iio_trigger_validate_own_device()
that can be used to do this check. Having a common implementation avoids
code duplication and unnecessary boiler-plate code.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/industrialio-trigger.c b/drivers/iio/industrialio-trigger.c
index e1e104845e38b223429bf73b504956d99061cd56..978729f6d7c47744d166648c9f8f4a4b490d4efb 100644 (file)
--- a/drivers/iio/industrialio-trigger.c
+++ b/drivers/iio/industrialio-trigger.c
@@ -717,6 +717,27 @@ bool iio_trigger_using_own(struct iio_dev *indio_dev)
 }
 EXPORT_SYMBOL(iio_trigger_using_own);
 
+/**
+ * iio_trigger_validate_own_device - Check if a trigger and IIO device belong to
+ *  the same device
+ * @trig: The IIO trigger to check
+ * @indio_dev: the IIO device to check
+ *
+ * This function can be used as the validate_device callback for triggers that
+ * can only be attached to their own device.
+ *
+ * Return: 0 if both the trigger and the IIO device belong to the same
+ * device, -EINVAL otherwise.
+ */
+int iio_trigger_validate_own_device(struct iio_trigger *trig,
+       struct iio_dev *indio_dev)
+{
+       if (indio_dev->dev.parent != trig->dev.parent)
+               return -EINVAL;
+       return 0;
+}
+EXPORT_SYMBOL(iio_trigger_validate_own_device);
+
 void iio_device_register_trigger_consumer(struct iio_dev *indio_dev)
 {
        indio_dev->groups[indio_dev->groupcounter++] =

diff --git a/include/linux/iio/trigger.h b/include/linux/iio/trigger.h
index 4f1154f7a33cb6b5d568e78a4d72f67aba6e311e..ea08302f2d7b27967fb1f0947dcede46411f396c 100644 (file)
--- a/include/linux/iio/trigger.h
+++ b/include/linux/iio/trigger.h
@@ -170,6 +170,8 @@ void iio_trigger_free(struct iio_trigger *trig);
  */
 bool iio_trigger_using_own(struct iio_dev *indio_dev);
 
+int iio_trigger_validate_own_device(struct iio_trigger *trig,
+                                    struct iio_dev *indio_dev);
 
 #else
 struct iio_trigger;