18 #include <linux/iio/buffer-dma.h>
26  * has its own memory buffer. The size of the block is the granularity at which
73  * the actual number of bytes in the buffer. Typically this will be equal to the
81  * perform a DMA transfer for the block, e.g. because the buffer was disabled
86  * It will be called when the buffer is disabled and can be used to cancel
112 	iio_buffer_put(&queue->buffer);  in iio_buffer_block_release()
171 	return container_of(buf, struct iio_dma_buffer_queue, buffer);  in iio_buffer_to_queue()
199 	iio_buffer_get(&queue->buffer);  in iio_dma_buffer_alloc_block()
217 	if (queue->buffer.direction == IIO_BUFFER_DIRECTION_IN)  in iio_dma_buffer_queue_wake()
222 	wake_up_interruptible_poll(&queue->buffer.pollq, flags);  in iio_dma_buffer_queue_wake()
296 	 * default case when enabling the buffer, unless the DMA controller does  in iio_dma_block_reusable()
319  * iio_dma_buffer_request_update() - DMA buffer request_update callback
320  * @buffer: The buffer which to request an update
325 int iio_dma_buffer_request_update(struct iio_buffer *buffer)  in iio_dma_buffer_request_update()  argument
327 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_request_update()
335 	 * Split the buffer into two even parts. This is used as a double  in iio_dma_buffer_request_update()
339 	size = DIV_ROUND_UP(queue->buffer.bytes_per_datum *  in iio_dma_buffer_request_update()
340 		queue->buffer.length, 2);  in iio_dma_buffer_request_update()
406 		 * If it's an input buffer, mark the block as queued, and  in iio_dma_buffer_request_update()
410 		if (queue->buffer.direction == IIO_BUFFER_DIRECTION_IN) {  in iio_dma_buffer_request_update()
471 		 * other then wait for the buffer to be disabled and re-enabled  in iio_dma_buffer_submit_block()
476 		 * notify consumers that something went wrong and the buffer  in iio_dma_buffer_submit_block()
484  * iio_dma_buffer_enable() - Enable DMA buffer
485  * @buffer: IIO buffer to enable
486  * @indio_dev: IIO device the buffer is attached to
488  * Needs to be called when the device that the buffer is attached to starts
493 int iio_dma_buffer_enable(struct iio_buffer *buffer,  in iio_dma_buffer_enable()  argument
496 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_enable()
512  * iio_dma_buffer_disable() - Disable DMA buffer
513  * @buffer: IIO DMA buffer to disable
514  * @indio_dev: IIO device the buffer is attached to
516  * Needs to be called when the device that the buffer is attached to stops
519 int iio_dma_buffer_disable(struct iio_buffer *buffer,  in iio_dma_buffer_disable()  argument
522 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_disable()
571 static int iio_dma_buffer_io(struct iio_buffer *buffer, size_t n,  in iio_dma_buffer_io()  argument
574 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_io()
579 	if (n < buffer->bytes_per_datum)  in iio_dma_buffer_io()
596 	n = rounddown(n, buffer->bytes_per_datum);  in iio_dma_buffer_io()
626  * iio_dma_buffer_read() - DMA buffer read callback
627  * @buffer: Buffer to read from
629  * @user_buffer: Userspace buffer to copy the data to
634 int iio_dma_buffer_read(struct iio_buffer *buffer, size_t n,  in iio_dma_buffer_read()  argument
637 	return iio_dma_buffer_io(buffer, n, user_buffer, false);  in iio_dma_buffer_read()
642  * iio_dma_buffer_write() - DMA buffer write callback
643  * @buffer: Buffer to write to
645  * @user_buffer: Userspace buffer to copy the data from
650 int iio_dma_buffer_write(struct iio_buffer *buffer, size_t n,  in iio_dma_buffer_write()  argument
653 	return iio_dma_buffer_io(buffer, n,  in iio_dma_buffer_write()
659  * iio_dma_buffer_usage() - DMA buffer data_available and
661  * @buf: Buffer to check for data availability
702 iio_dma_buffer_attach_dmabuf(struct iio_buffer *buffer,  in iio_dma_buffer_attach_dmabuf()  argument
705 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_attach_dmabuf()
711 	 * If the buffer is enabled and in fileio mode new blocks can't be  in iio_dma_buffer_attach_dmabuf()
728 void iio_dma_buffer_detach_dmabuf(struct iio_buffer *buffer,  in iio_dma_buffer_detach_dmabuf()  argument
757 int iio_dma_buffer_enqueue_dmabuf(struct iio_buffer *buffer,  in iio_dma_buffer_enqueue_dmabuf()  argument
763 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_enqueue_dmabuf()
789 struct device *iio_dma_buffer_get_dma_dev(struct iio_buffer *buffer)  in iio_dma_buffer_get_dma_dev()  argument
791 	return iio_buffer_to_queue(buffer)->dev;  in iio_dma_buffer_get_dma_dev()
795 void iio_dma_buffer_lock_queue(struct iio_buffer *buffer)  in iio_dma_buffer_lock_queue()  argument
797 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_lock_queue()
803 void iio_dma_buffer_unlock_queue(struct iio_buffer *buffer)  in iio_dma_buffer_unlock_queue()  argument
805 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_unlock_queue()
812  * iio_dma_buffer_set_bytes_per_datum() - DMA buffer set_bytes_per_datum callback
813  * @buffer: Buffer to set the bytes-per-datum for
819 int iio_dma_buffer_set_bytes_per_datum(struct iio_buffer *buffer, size_t bpd)  in iio_dma_buffer_set_bytes_per_datum()  argument
821 	buffer->bytes_per_datum = bpd;  in iio_dma_buffer_set_bytes_per_datum()
828  * iio_dma_buffer_set_length - DMA buffer set_length callback
829  * @buffer: Buffer to set the length for
830  * @length: The new buffer length
835 int iio_dma_buffer_set_length(struct iio_buffer *buffer, unsigned int length)  in iio_dma_buffer_set_length()  argument
840 	buffer->length = length;  in iio_dma_buffer_set_length()
841 	buffer->watermark = length / 2;  in iio_dma_buffer_set_length()
848  * iio_dma_buffer_init() - Initialize DMA buffer queue
849  * @queue: Buffer to initialize
851  * @ops: DMA buffer queue callback operations
860 	iio_buffer_init(&queue->buffer);  in iio_dma_buffer_init()
861 	queue->buffer.length = PAGE_SIZE;  in iio_dma_buffer_init()
862 	queue->buffer.watermark = queue->buffer.length / 2;  in iio_dma_buffer_init()
876  * iio_dma_buffer_exit() - Cleanup DMA buffer queue
877  * @queue: Buffer to cleanup
880  * associated with the buffer and are accessed inside the callback operations.
894  * iio_dma_buffer_release() - Release final buffer resources
895  * @queue: Buffer to release
899  * the memory associated with the buffer.
908 MODULE_DESCRIPTION("DMA buffer for the IIO framework");