/* * linux/arch/arm/kernel/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)(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 { dmasg_t buf; /* single DMA */ int sgcount; /* number of DMA SG */ dmasg_t *sg; /* DMA Scatter-Gather List */ unsigned int active:1; /* Transfer active */ unsigned int invalid:1; /* Address/Count changed */ 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 */ int state; /* Controller state */ dmasg_t cur_sg; /* Current controller buffer */ struct dma_ops *d_ops; }; /* Prototype: void arch_dma_init(dma) * Purpose : Initialise architecture specific DMA * Params : dma - pointer to array of DMA structures */ void arch_dma_init(dma_t *dma);