Introduce a new flag IIO_BUFFER_DMABUF_CYCLIC in the "flags" field of the iio_dmabuf uapi structure. When set, the DMABUF enqueued with the enqueue ioctl will be endlessly repeated on the TX output, until the buffer is disabled. Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx> --- drivers/iio/industrialio-buffer.c | 5 +++++ include/uapi/linux/iio/buffer.h | 3 ++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c index 30910e6c2346..41bc51c88002 100644 --- a/drivers/iio/industrialio-buffer.c +++ b/drivers/iio/industrialio-buffer.c @@ -1600,6 +1600,11 @@ static int iio_buffer_enqueue_dmabuf(struct iio_buffer *buffer, if (dmabuf.flags & ~IIO_BUFFER_DMABUF_SUPPORTED_FLAGS) return -EINVAL; + /* Cyclic flag is only supported on output buffers */ + if ((dmabuf.flags & IIO_BUFFER_DMABUF_CYCLIC) && + buffer->direction != IIO_BUFFER_DIRECTION_OUT) + return -EINVAL; + return buffer->access->enqueue_dmabuf(buffer, &dmabuf); } diff --git a/include/uapi/linux/iio/buffer.h b/include/uapi/linux/iio/buffer.h index e4621b926262..2d541d038c02 100644 --- a/include/uapi/linux/iio/buffer.h +++ b/include/uapi/linux/iio/buffer.h @@ -7,7 +7,8 @@ #include <linux/types.h> -#define IIO_BUFFER_DMABUF_SUPPORTED_FLAGS 0x00000000 +#define IIO_BUFFER_DMABUF_CYCLIC (1 << 0) +#define IIO_BUFFER_DMABUF_SUPPORTED_FLAGS 0x00000001 /** * struct iio_dmabuf_alloc_req - Descriptor for allocating IIO DMABUFs -- 2.33.0