iio: Move buffer registration to the core

Originally device and buffer registration were kept as separate operations
in IIO to allow to register two distinct sets of channels for buffered and
non-buffered operations. This has since already been further restricted and
the channel set registered for the buffer needs to be a subset of the
channel set registered for the device. Additionally the possibility to not
have a raw (or processed) attribute for a channel which was registered for
the device was added a while ago. This means it is possible to not register
any device level attributes for a channel even if it is registered for the
device. Also if a channel's scan_index is set to -1 and the channel is
registered for the buffer it is ignored.

So in summary it means it is possible to register the same channel array for
both the device and the buffer yet still end up with distinctive sets of
channels for both of them. This makes the argument for having to have to
manually register the channels for both the device and the buffer invalid.
Considering that the vast majority of all drivers want to register the same
set of channels for both the buffer and the device it makes sense to move
the buffer registration into the core to avoid some boiler-plate code in the
device driver setup path.

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

1 files changed, 1 insertions, 10 deletions

diff --git a/drivers/iio/industrialio-triggered-buffer.c b/drivers/iio/industrialio-triggered-buffer.c
index d6f54930b34a..61a5d0404edf 100644
--- a/drivers/iio/industrialio-triggered-buffer.c
+++ b/drivers/iio/industrialio-triggered-buffer.c
@@ -32,7 +32,7 @@ static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = {
  *
  * This function combines some common tasks which will normally be performed
  * when setting up a triggered buffer. It will allocate the buffer and the
- * pollfunc, as well as register the buffer with the IIO core.
+ * pollfunc.
  *
  * Before calling this function the indio_dev structure should already be
  * completely initialized, but not yet registered. In practice this means that
@@ -78,16 +78,8 @@ int iio_triggered_buffer_setup(struct iio_dev *indio_dev,
 	/* Flag that polled ring buffering is possible */
 	indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
 
-	ret = iio_buffer_register(indio_dev,
-				  indio_dev->channels,
-				  indio_dev->num_channels);
-	if (ret)
-		goto error_dealloc_pollfunc;
-
 	return 0;
 
-error_dealloc_pollfunc:
-	iio_dealloc_pollfunc(indio_dev->pollfunc);
 error_kfifo_free:
 	iio_kfifo_free(indio_dev->buffer);
 error_ret:
@@ -101,7 +93,6 @@ EXPORT_SYMBOL(iio_triggered_buffer_setup);
  */
 void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)
 {
-	iio_buffer_unregister(indio_dev);
 	iio_dealloc_pollfunc(indio_dev->pollfunc);
 	iio_kfifo_free(indio_dev->buffer);
 }