146 lines
4.5 KiB
C
146 lines
4.5 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* Copyright 2013-2015 Analog Devices Inc.
|
|
* Author: Lars-Peter Clausen <lars@metafoo.de>
|
|
*/
|
|
|
|
#ifndef __INDUSTRIALIO_DMA_BUFFER_H__
|
|
#define __INDUSTRIALIO_DMA_BUFFER_H__
|
|
|
|
#include <linux/list.h>
|
|
#include <linux/kref.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/iio/buffer_impl.h>
|
|
|
|
struct iio_dma_buffer_queue;
|
|
struct iio_dma_buffer_ops;
|
|
struct device;
|
|
|
|
/**
|
|
* enum iio_block_state - State of a struct iio_dma_buffer_block
|
|
* @IIO_BLOCK_STATE_QUEUED: Block is on the incoming queue
|
|
* @IIO_BLOCK_STATE_ACTIVE: Block is currently being processed by the DMA
|
|
* @IIO_BLOCK_STATE_DONE: Block is on the outgoing queue
|
|
* @IIO_BLOCK_STATE_DEAD: Block has been marked as to be freed
|
|
*/
|
|
enum iio_block_state {
|
|
IIO_BLOCK_STATE_QUEUED,
|
|
IIO_BLOCK_STATE_ACTIVE,
|
|
IIO_BLOCK_STATE_DONE,
|
|
IIO_BLOCK_STATE_DEAD,
|
|
};
|
|
|
|
/**
|
|
* struct iio_dma_buffer_block - IIO buffer block
|
|
* @head: List head
|
|
* @size: Total size of the block in bytes
|
|
* @bytes_used: Number of bytes that contain valid data
|
|
* @vaddr: Virutal address of the blocks memory
|
|
* @phys_addr: Physical address of the blocks memory
|
|
* @queue: Parent DMA buffer queue
|
|
* @kref: kref used to manage the lifetime of block
|
|
* @state: Current state of the block
|
|
*/
|
|
struct iio_dma_buffer_block {
|
|
/* May only be accessed by the owner of the block */
|
|
struct list_head head;
|
|
size_t bytes_used;
|
|
|
|
/*
|
|
* Set during allocation, constant thereafter. May be accessed read-only
|
|
* by anybody holding a reference to the block.
|
|
*/
|
|
void *vaddr;
|
|
dma_addr_t phys_addr;
|
|
size_t size;
|
|
struct iio_dma_buffer_queue *queue;
|
|
|
|
/* Must not be accessed outside the core. */
|
|
struct kref kref;
|
|
/*
|
|
* Must not be accessed outside the core. Access needs to hold
|
|
* queue->list_lock if the block is not owned by the core.
|
|
*/
|
|
enum iio_block_state state;
|
|
};
|
|
|
|
/**
|
|
* struct iio_dma_buffer_queue_fileio - FileIO state for the DMA buffer
|
|
* @blocks: Buffer blocks used for fileio
|
|
* @active_block: Block being used in read()
|
|
* @pos: Read offset in the active block
|
|
* @block_size: Size of each block
|
|
* @next_dequeue: index of next block that will be dequeued
|
|
*/
|
|
struct iio_dma_buffer_queue_fileio {
|
|
struct iio_dma_buffer_block *blocks[2];
|
|
struct iio_dma_buffer_block *active_block;
|
|
size_t pos;
|
|
size_t block_size;
|
|
|
|
unsigned int next_dequeue;
|
|
};
|
|
|
|
/**
|
|
* struct iio_dma_buffer_queue - DMA buffer base structure
|
|
* @buffer: IIO buffer base structure
|
|
* @dev: Parent device
|
|
* @ops: DMA buffer callbacks
|
|
* @lock: Protects the incoming list, active and the fields in the fileio
|
|
* substruct
|
|
* @list_lock: Protects lists that contain blocks which can be modified in
|
|
* atomic context as well as blocks on those lists. This is the outgoing queue
|
|
* list and typically also a list of active blocks in the part that handles
|
|
* the DMA controller
|
|
* @incoming: List of buffers on the incoming queue
|
|
* @active: Whether the buffer is currently active
|
|
* @fileio: FileIO state
|
|
*/
|
|
struct iio_dma_buffer_queue {
|
|
struct iio_buffer buffer;
|
|
struct device *dev;
|
|
const struct iio_dma_buffer_ops *ops;
|
|
|
|
struct mutex lock;
|
|
spinlock_t list_lock;
|
|
struct list_head incoming;
|
|
|
|
bool active;
|
|
|
|
struct iio_dma_buffer_queue_fileio fileio;
|
|
};
|
|
|
|
/**
|
|
* struct iio_dma_buffer_ops - DMA buffer callback operations
|
|
* @submit: Called when a block is submitted to the DMA controller
|
|
* @abort: Should abort all pending transfers
|
|
*/
|
|
struct iio_dma_buffer_ops {
|
|
int (*submit)(struct iio_dma_buffer_queue *queue,
|
|
struct iio_dma_buffer_block *block);
|
|
void (*abort)(struct iio_dma_buffer_queue *queue);
|
|
};
|
|
|
|
void iio_dma_buffer_block_done(struct iio_dma_buffer_block *block);
|
|
void iio_dma_buffer_block_list_abort(struct iio_dma_buffer_queue *queue,
|
|
struct list_head *list);
|
|
|
|
int iio_dma_buffer_enable(struct iio_buffer *buffer,
|
|
struct iio_dev *indio_dev);
|
|
int iio_dma_buffer_disable(struct iio_buffer *buffer,
|
|
struct iio_dev *indio_dev);
|
|
int iio_dma_buffer_read(struct iio_buffer *buffer, size_t n,
|
|
char __user *user_buffer);
|
|
size_t iio_dma_buffer_data_available(struct iio_buffer *buffer);
|
|
int iio_dma_buffer_set_bytes_per_datum(struct iio_buffer *buffer, size_t bpd);
|
|
int iio_dma_buffer_set_length(struct iio_buffer *buffer, unsigned int length);
|
|
int iio_dma_buffer_request_update(struct iio_buffer *buffer);
|
|
|
|
int iio_dma_buffer_init(struct iio_dma_buffer_queue *queue,
|
|
struct device *dma_dev, const struct iio_dma_buffer_ops *ops);
|
|
void iio_dma_buffer_exit(struct iio_dma_buffer_queue *queue);
|
|
void iio_dma_buffer_release(struct iio_dma_buffer_queue *queue);
|
|
|
|
#endif
|