From ee708e6baacd3afdace9b721c25fbbe106cebb94 Mon Sep 17 00:00:00 2001 From: Alexandru Ardelean Date: Mon, 15 Feb 2021 12:40:38 +0200 Subject: iio: buffer: introduce support for attaching more IIO buffers With this change, calling iio_device_attach_buffer() will actually attach more buffers. Right now this doesn't do any validation of whether a buffer is attached twice; maybe that can be added later (if needed). Attaching a buffer more than once should yield noticeably bad results. The first buffer is the legacy buffer, so a reference is kept to it. At this point, accessing the data for the extra buffers (that are added after the first one) isn't possible yet. The iio_device_attach_buffer() is also changed to return an error code, which for now is -ENOMEM if the array could not be realloc-ed for more buffers. To adapt to this new change iio_device_attach_buffer() is called last in all place where it's called. The realloc failure is a bit difficult to handle during un-managed calls when unwinding, so it's better to have this as the last error in the setup_buffer calls. At this point, no driver should call iio_device_attach_buffer() directly, it should call one of the {devm_}iio_triggered_buffer_setup() or devm_iio_kfifo_buffer_setup() or devm_iio_dmaengine_buffer_setup() functions. This makes iio_device_attach_buffer() a bit easier to handle. Signed-off-by: Alexandru Ardelean Link: https://lore.kernel.org/r/20210215104043.91251-20-alexandru.ardelean@analog.com Signed-off-by: Jonathan Cameron --- include/linux/iio/buffer.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/iio/buffer.h') diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h index 8febc23f5f26..b6928ac5c63d 100644 --- a/include/linux/iio/buffer.h +++ b/include/linux/iio/buffer.h @@ -41,7 +41,7 @@ static inline int iio_push_to_buffers_with_timestamp(struct iio_dev *indio_dev, bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev, const unsigned long *mask); -void iio_device_attach_buffer(struct iio_dev *indio_dev, - struct iio_buffer *buffer); +int iio_device_attach_buffer(struct iio_dev *indio_dev, + struct iio_buffer *buffer); #endif /* _IIO_BUFFER_GENERIC_H_ */ -- cgit v1.2.3