On 10/14/13 17:49, Lars-Peter Clausen wrote:
> Currently a IIO device driver needs to make sure to update the buffer's bytes
> per datum after the scan mask has changed. This is usually done in the preenable
> callback by invoking iio_sw_buffer_preenable(). This is something that needs to
> be done and is done for virtually all devices which support buffers (we
> currently have only one exception). Also this a bit of a layering violation
> since we have to call the buffer setup ops from the device setup ops. This
> requires the device driver to know about the internal requirements of the buffer
> (e.g. whether we need to call the set_bytes_per_datum) callback. And especially
> with in-kernel buffer consumers, which allows to attach arbitrary buffers to a
> device, this is something that the driver can't know.
>
> Moving this to the core allows us to drop the individual calls to
> iio_sw_buffer_preenable() from drivers.
A very sensible little cleanup. I'll let this sit for a day or two to
let anyone else comment. The previous approach was definitely one of
those bits of code that evolved into something far from ideal!
Thanks,
Jonathan
>
> Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
> Cc: Denis Ciocca <denis.ciocca@xxxxxx>
> Cc: Marek Vasut <marex@xxxxxxx>
> Cc: Zubair Lutfullah <zubair.lutfullah@xxxxxxxxx>
> Cc: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>
> ---
> drivers/iio/industrialio-buffer.c | 18 +++++++++++++++++-
> 1 file changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
> index 796376a..186f501 100644
> --- a/drivers/iio/industrialio-buffer.c
> +++ b/drivers/iio/industrialio-buffer.c
> @@ -492,6 +492,20 @@ void iio_disable_all_buffers(struct iio_dev *indio_dev)
> indio_dev->setup_ops->postdisable(indio_dev);
> }
>
> +static void iio_buffer_update_bytes_per_datum(struct iio_dev *indio_dev,
> + struct iio_buffer *buffer)
> +{
> + unsigned int bytes;
> +
> + if (!buffer->access->set_bytes_per_datum)
> + return;
> +
> + bytes = iio_compute_scan_bytes(indio_dev, buffer->scan_mask,
> + buffer->scan_timestamp);
> +
> + buffer->access->set_bytes_per_datum(buffer, bytes);
> +}
> +
> static int __iio_update_buffers(struct iio_dev *indio_dev,
> struct iio_buffer *insert_buffer,
> struct iio_buffer *remove_buffer)
> @@ -589,7 +603,8 @@ static int __iio_update_buffers(struct iio_dev *indio_dev,
> iio_compute_scan_bytes(indio_dev,
> indio_dev->active_scan_mask,
> indio_dev->scan_timestamp);
> - list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list)
> + list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) {
> + iio_buffer_update_bytes_per_datum(indio_dev, buffer);
> if (buffer->access->request_update) {
> ret = buffer->access->request_update(buffer);
> if (ret) {
> @@ -598,6 +613,7 @@ static int __iio_update_buffers(struct iio_dev *indio_dev,
> goto error_run_postdisable;
> }
> }
> + }
> if (indio_dev->info->update_scan_mode) {
> ret = indio_dev->info
> ->update_scan_mode(indio_dev,
>
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
