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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* arch/arm/include/asm/mach/dma.h
*
* Copyright (C) 1998-2000 Russell King
*
* This header file describes the interface between the generic DMA handler
* (dma.c) and the architecture-specific DMA backends (dma-*.c)
*/
struct dma_struct;
typedef struct dma_struct dma_t;
struct dma_ops {
int (*request)(unsigned int, dma_t *); /* optional */
void (*free)(unsigned int, dma_t *); /* optional */
void (*enable)(unsigned int, dma_t *); /* mandatory */
void (*disable)(unsigned int, dma_t *); /* mandatory */
int (*residue)(unsigned int, dma_t *); /* optional */
int (*setspeed)(unsigned int, dma_t *, int); /* optional */
const char *type;
};
struct dma_struct {
void *addr; /* single DMA address */
unsigned long count; /* single DMA size */
struct scatterlist buf; /* single DMA */
int sgcount; /* number of DMA SG */
struct scatterlist *sg; /* DMA Scatter-Gather List */
unsigned int active:1; /* Transfer active */
unsigned int invalid:1; /* Address/Count changed */
unsigned int dma_mode; /* DMA mode */
int speed; /* DMA speed */
unsigned int lock; /* Device is allocated */
const char *device_id; /* Device name */
const struct dma_ops *d_ops;
};
/*
* isa_dma_add - add an ISA-style DMA channel
*/
extern int isa_dma_add(unsigned int, dma_t *dma);
/*
* Add the ISA DMA controller. Always takes channels 0-7.
*/
extern void isa_init_dma(void);
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