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/*
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* arch/arm/kernel/dma.h
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*
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* Copyright (C) 1998 Russell King
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*
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* This header file describes the interface between the generic DMA handler
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* (dma.c) and the architecture-specific DMA backends (dma-*.c)
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*/
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typedef struct {
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dmasg_t buf; /* single DMA */
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int sgcount; /* number of DMA SG */
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dmasg_t *sg; /* DMA Scatter-Gather List */
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unsigned int active:1; /* Transfer active */
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unsigned int invalid:1; /* Address/Count changed */
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dmamode_t dma_mode; /* DMA mode */
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unsigned int lock; /* Device is allocated */
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const char *device_id; /* Device name */
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unsigned int dma_base; /* Controller base address */
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int dma_irq; /* Controller IRQ */
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int state; /* Controller state */
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dmasg_t cur_sg; /* Current controller buffer */
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} dma_t;
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/* Prototype: int arch_request_dma(channel, dma, dev_id)
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* Purpose : Perform architecture specific claiming of a DMA channel
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* Params : channel - DMA channel number
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* : dma - DMA structure (above) for channel
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* : dev_id - device ID string passed with request
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* Returns : 0 on success, E????? number on error
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*/
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int arch_request_dma(dmach_t channel, dma_t *dma, const char *dev_id);
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/* Prototype: int arch_free_dma(channel, dma)
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* Purpose : Perform architecture specific freeing of a DMA channel
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* Params : channel - DMA channel number
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* : dma - DMA structure for channel
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*/
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void arch_free_dma(dmach_t channel, dma_t *dma);
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/* Prototype: void arch_enable_dma(channel, dma)
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* Purpose : Enable a claimed DMA channel
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* Params : channel - DMA channel number
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* : dma - DMA structure for channel
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*/
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void arch_enable_dma(dmach_t channel, dma_t *dma);
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/* Prototype: void arch_disable_dma(channel, dma)
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* Purpose : Disable a claimed DMA channel
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* Params : channel - DMA channel number
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* : dma - DMA structure for channel
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*/
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void arch_disable_dma(dmach_t channel, dma_t *dma);
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/* Prototype: int arch_get_dma_residue(channel, dma)
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* Purpose : Return number of bytes left to DMA
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* Params : channel - DMA channel number
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* : dma - DMA structure for channel
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* Returns : Number of bytes left to DMA
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*/
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int arch_get_dma_residue(dmach_t channel, dma_t *dma);
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/* Prototype: void arch_dma_init(dma)
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* Purpose : Initialise architecture specific DMA
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* Params : dma - pointer to array of DMA structures
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*/
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void arch_dma_init(dma_t *dma);
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