iio:buffer: Ignore noop requests for iio_update_buffers()
Since the kernel now disables all buffers when a device is unregistered it might
happen that a in-kernel consumer tries to disable that buffer again. So ignore
requests where the buffer already is in the desired state.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index d12b384..796376a 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -664,9 +664,23 @@
{
int ret;
+ if (insert_buffer == remove_buffer)
+ return 0;
+
mutex_lock(&indio_dev->info_exist_lock);
mutex_lock(&indio_dev->mlock);
+ if (insert_buffer && iio_buffer_is_active(insert_buffer))
+ insert_buffer = NULL;
+
+ if (remove_buffer && !iio_buffer_is_active(remove_buffer))
+ remove_buffer = NULL;
+
+ if (!insert_buffer && !remove_buffer) {
+ ret = 0;
+ goto out_unlock;
+ }
+
if (indio_dev->info == NULL) {
ret = -ENODEV;
goto out_unlock;