19 #include <linux/iio/buffer-dma.h>
27  * has its own memory buffer. The size of the block is the granularity at which
74  * the actual number of bytes in the buffer. Typically this will be equal to the
82  * perform a DMA transfer for the block, e.g. because the buffer was disabled
87  * It will be called when the buffer is disabled and can be used to cancel
113 	iio_buffer_put(&queue->buffer);  in iio_buffer_block_release()
169 	return container_of(buf, struct iio_dma_buffer_queue, buffer);  in iio_buffer_to_queue()
195 	iio_buffer_get(&queue->buffer);  in iio_dma_buffer_alloc_block()
213 	if (queue->buffer.direction == IIO_BUFFER_DIRECTION_IN)  in iio_dma_buffer_queue_wake()
218 	wake_up_interruptible_poll(&queue->buffer.pollq, flags);  in iio_dma_buffer_queue_wake()
290 	 * default case when enabling the buffer, unless the DMA controller does  in iio_dma_block_reusable()
313  * iio_dma_buffer_request_update() - DMA buffer request_update callback
314  * @buffer: The buffer which to request an update
319 int iio_dma_buffer_request_update(struct iio_buffer *buffer)  in iio_dma_buffer_request_update()  argument
321 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_request_update()
328 	 * Split the buffer into two even parts. This is used as a double  in iio_dma_buffer_request_update()
332 	size = DIV_ROUND_UP(queue->buffer.bytes_per_datum *  in iio_dma_buffer_request_update()
333 		queue->buffer.length, 2);  in iio_dma_buffer_request_update()
398 		 * If it's an input buffer, mark the block as queued, and  in iio_dma_buffer_request_update()
402 		if (queue->buffer.direction == IIO_BUFFER_DIRECTION_IN) {  in iio_dma_buffer_request_update()
460 		 * other then wait for the buffer to be disabled and re-enabled  in iio_dma_buffer_submit_block()
465 		 * notify consumers that something went wrong and the buffer  in iio_dma_buffer_submit_block()
473  * iio_dma_buffer_enable() - Enable DMA buffer
474  * @buffer: IIO buffer to enable
475  * @indio_dev: IIO device the buffer is attached to
477  * Needs to be called when the device that the buffer is attached to starts
482 int iio_dma_buffer_enable(struct iio_buffer *buffer, struct iio_dev *indio_dev)  in iio_dma_buffer_enable()  argument
484 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_enable()
499  * iio_dma_buffer_disable() - Disable DMA buffer
500  * @buffer: IIO DMA buffer to disable
501  * @indio_dev: IIO device the buffer is attached to
503  * Needs to be called when the device that the buffer is attached to stops
506 int iio_dma_buffer_disable(struct iio_buffer *buffer, struct iio_dev *indio_dev)  in iio_dma_buffer_disable()  argument
508 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_disable()
553 static int iio_dma_buffer_io(struct iio_buffer *buffer, size_t n,  in iio_dma_buffer_io()  argument
556 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_io()
561 	if (n < buffer->bytes_per_datum)  in iio_dma_buffer_io()
577 	n = rounddown(n, buffer->bytes_per_datum);  in iio_dma_buffer_io()
600  * iio_dma_buffer_read() - DMA buffer read callback
601  * @buffer: Buffer to read from
603  * @user_buffer: Userspace buffer to copy the data to
608 int iio_dma_buffer_read(struct iio_buffer *buffer, size_t n,  in iio_dma_buffer_read()  argument
611 	return iio_dma_buffer_io(buffer, n, user_buffer, false);  in iio_dma_buffer_read()
616  * iio_dma_buffer_write() - DMA buffer write callback
617  * @buffer: Buffer to write to
619  * @user_buffer: Userspace buffer to copy the data from
624 int iio_dma_buffer_write(struct iio_buffer *buffer, size_t n,  in iio_dma_buffer_write()  argument
627 	return iio_dma_buffer_io(buffer, n,  in iio_dma_buffer_write()
633  * iio_dma_buffer_usage() - DMA buffer data_available and
635  * @buf: Buffer to check for data availability
672 iio_dma_buffer_attach_dmabuf(struct iio_buffer *buffer,  in iio_dma_buffer_attach_dmabuf()  argument
675 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_attach_dmabuf()
681 	 * If the buffer is enabled and in fileio mode new blocks can't be  in iio_dma_buffer_attach_dmabuf()
698 void iio_dma_buffer_detach_dmabuf(struct iio_buffer *buffer,  in iio_dma_buffer_detach_dmabuf()  argument
727 int iio_dma_buffer_enqueue_dmabuf(struct iio_buffer *buffer,  in iio_dma_buffer_enqueue_dmabuf()  argument
733 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_enqueue_dmabuf()
759 struct device *iio_dma_buffer_get_dma_dev(struct iio_buffer *buffer)  in iio_dma_buffer_get_dma_dev()  argument
761 	return iio_buffer_to_queue(buffer)->dev;  in iio_dma_buffer_get_dma_dev()
765 void iio_dma_buffer_lock_queue(struct iio_buffer *buffer)  in iio_dma_buffer_lock_queue()  argument
767 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_lock_queue()
773 void iio_dma_buffer_unlock_queue(struct iio_buffer *buffer)  in iio_dma_buffer_unlock_queue()  argument
775 	struct iio_dma_buffer_queue *queue = iio_buffer_to_queue(buffer);  in iio_dma_buffer_unlock_queue()
782  * iio_dma_buffer_set_bytes_per_datum() - DMA buffer set_bytes_per_datum callback
783  * @buffer: Buffer to set the bytes-per-datum for
789 int iio_dma_buffer_set_bytes_per_datum(struct iio_buffer *buffer, size_t bpd)  in iio_dma_buffer_set_bytes_per_datum()  argument
791 	buffer->bytes_per_datum = bpd;  in iio_dma_buffer_set_bytes_per_datum()
798  * iio_dma_buffer_set_length - DMA buffer set_length callback
799  * @buffer: Buffer to set the length for
800  * @length: The new buffer length
805 int iio_dma_buffer_set_length(struct iio_buffer *buffer, unsigned int length)  in iio_dma_buffer_set_length()  argument
810 	buffer->length = length;  in iio_dma_buffer_set_length()
811 	buffer->watermark = length / 2;  in iio_dma_buffer_set_length()
818  * iio_dma_buffer_init() - Initialize DMA buffer queue
819  * @queue: Buffer to initialize
821  * @ops: DMA buffer queue callback operations
830 	iio_buffer_init(&queue->buffer);  in iio_dma_buffer_init()
831 	queue->buffer.length = PAGE_SIZE;  in iio_dma_buffer_init()
832 	queue->buffer.watermark = queue->buffer.length / 2;  in iio_dma_buffer_init()
844  * iio_dma_buffer_exit() - Cleanup DMA buffer queue
845  * @queue: Buffer to cleanup
848  * associated with the buffer and are accessed inside the callback operations.
860  * iio_dma_buffer_release() - Release final buffer resources
861  * @queue: Buffer to release
865  * the memory associated with the buffer.
874 MODULE_DESCRIPTION("DMA buffer for the IIO framework");