[PATCH 07/14] iio: triggers: on pollfunc attach, complete iio_dev if NULL

Eugen Hristev
2017-12-22T15:07:14Z

When attaching a pollfunc to a trigger, if the pollfunc does not
have an associated iio_dev pointer, just use the private data
iio_dev pointer from the trigger to fill in the poll func required
iio_dev reference.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
---
drivers/iio/industrialio-trigger.c | 9 +++++++++
include/linux/iio/trigger_consumer.h | 2 ++
2 files changed, 11 insertions(+)

diff --git a/drivers/iio/industrialio-trigger.c b/drivers/iio/industrialio-trigger.c
index 8565c92..ab180bd 100644
--- a/drivers/iio/industrialio-trigger.c
+++ b/drivers/iio/industrialio-trigger.c
@@ -272,6 +272,15 @@ int iio_trigger_attach_poll_func(struct iio_trigger *trig,
bool notinuse
= bitmap_empty(trig->pool, CONFIG_IIO_CONSUMERS_PER_TRIGGER);

+ /*
+ * If we did not get a iio_dev in the poll func, attempt to
+ * obtain the trigger's owner's device struct
+ */
+ if (!pf->indio_dev)
+ pf->indio_dev = iio_trigger_get_drvdata(trig);
+ if (!pf->indio_dev)
+ return -EINVAL;
+
/* Prevent the module from being removed whilst attached to a trigger */
__module_get(pf->indio_dev->driver_module);

diff --git a/include/linux/iio/trigger_consumer.h b/include/linux/iio/trigger_consumer.h
index aeefcdb..36e2a02 100644
--- a/include/linux/iio/trigger_consumer.h
+++ b/include/linux/iio/trigger_consumer.h
@@ -63,6 +63,8 @@ int iio_triggered_buffer_predisable(struct iio_dev *indio_dev);
/*
* Two functions for the uncommon case when we need to attach or detach
* a specific pollfunc to and from a trigger
+ * If the pollfunc has a NULL iio_dev pointer, it will be filled from the
+ * trigger struct.
*/
int iio_trigger_attach_poll_func(struct iio_trigger *trig,
struct iio_poll_func *pf);
--
2.7.4