iio: Wakeup poll and blocking reads when the device is unregistered
Once the device has been unregistered there won't be any new data no matter how
long a userspace application waits, so we might as well wake them up and let
them know.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/industrialio-event.c b/drivers/iio/industrialio-event.c
index 837d450..d251f30 100644
--- a/drivers/iio/industrialio-event.c
+++ b/drivers/iio/industrialio-event.c
@@ -113,9 +113,14 @@
}
/* Blocking on device; waiting for something to be there */
ret = wait_event_interruptible_locked_irq(ev_int->wait,
- !kfifo_is_empty(&ev_int->det_events));
+ !kfifo_is_empty(&ev_int->det_events) ||
+ indio_dev->info == NULL);
if (ret)
goto error_unlock;
+ if (indio_dev->info == NULL) {
+ ret = -ENODEV;
+ goto error_unlock;
+ }
/* Single access device so no one else can get the data */
}
@@ -454,6 +459,20 @@
return ret;
}
+/**
+ * iio_device_wakeup_eventset - Wakes up the event waitqueue
+ * @indio_dev: The IIO device
+ *
+ * Wakes up the event waitqueue used for poll() and blocking read().
+ * Should usually be called when the device is unregistered.
+ */
+void iio_device_wakeup_eventset(struct iio_dev *indio_dev)
+{
+ if (indio_dev->event_interface == NULL)
+ return;
+ wake_up(&indio_dev->event_interface->wait);
+}
+
void iio_device_unregister_eventset(struct iio_dev *indio_dev)
{
if (indio_dev->event_interface == NULL)
