1/* 2 * arch/arm/include/asm/mach/dma.h 3 * 4 * Copyright (C) 1998-2000 Russell King 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 * 10 * This header file describes the interface between the generic DMA handler 11 * (dma.c) and the architecture-specific DMA backends (dma-*.c) 12 */ 13 14struct dma_struct; 15typedef struct dma_struct dma_t; 16 17struct dma_ops { 18 int (*request)(unsigned int, dma_t *); /* optional */ 19 void (*free)(unsigned int, dma_t *); /* optional */ 20 void (*enable)(unsigned int, dma_t *); /* mandatory */ 21 void (*disable)(unsigned int, dma_t *); /* mandatory */ 22 int (*residue)(unsigned int, dma_t *); /* optional */ 23 int (*setspeed)(unsigned int, dma_t *, int); /* optional */ 24 const char *type; 25}; 26 27struct dma_struct { 28 void *addr; /* single DMA address */ 29 unsigned long count; /* single DMA size */ 30 struct scatterlist buf; /* single DMA */ 31 int sgcount; /* number of DMA SG */ 32 struct scatterlist *sg; /* DMA Scatter-Gather List */ 33 34 unsigned int active:1; /* Transfer active */ 35 unsigned int invalid:1; /* Address/Count changed */ 36 37 unsigned int dma_mode; /* DMA mode */ 38 int speed; /* DMA speed */ 39 40 unsigned int lock; /* Device is allocated */ 41 const char *device_id; /* Device name */ 42 43 const struct dma_ops *d_ops; 44}; 45 46/* 47 * isa_dma_add - add an ISA-style DMA channel 48 */ 49extern int isa_dma_add(unsigned int, dma_t *dma); 50 51/* 52 * Add the ISA DMA controller. Always takes channels 0-7. 53 */ 54extern void isa_init_dma(void); 55