/* *  linux/include/asm-arm/mach/dma.h * *  Copyright (C) 1998-2000 Russell King * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * *  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)(dmach_t, dma_t *);		/* optional */	void	(*free)(dmach_t, dma_t *);		/* optional */	void	(*enable)(dmach_t, dma_t *);		/* mandatory */	void 	(*disable)(dmach_t, dma_t *);		/* mandatory */	int	(*residue)(dmach_t, dma_t *);		/* optional */	int	(*setspeed)(dmach_t, dma_t *, int);	/* optional */	char	*type;};struct dma_struct {	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	using_sg:1;	/* using scatter list?		*/	dmamode_t	dma_mode;	/* DMA mode			*/	int		speed;		/* DMA speed			*/	unsigned int	lock;		/* Device is allocated		*/	const char	*device_id;	/* Device name			*/	unsigned int	dma_base;	/* Controller base address	*/	int		dma_irq;	/* Controller IRQ		*/	struct scatterlist cur_sg;	/* Current controller buffer	*/	unsigned int	state;	struct dma_ops	*d_ops;};/* Prototype: void arch_dma_init(dma) * Purpose  : Initialise architecture specific DMA * Params   : dma - pointer to array of DMA structures */extern void arch_dma_init(dma_t *dma);extern void isa_init_dma(dma_t *dma);