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#ifndef __ASM_ARM_DMA_H
#define __ASM_ARM_DMA_H

typedef unsigned int dmach_t;

#include <asm/irq.h>
#include <asm/arch/dma.h>

typedef struct {
	unsigned long address;
	unsigned long length;
} dmasg_t;

extern const char dma_str[];

/* Clear the 'DMA Pointer Flip Flop'.
 * Write 0 for LSB/MSB, 1 for MSB/LSB access.
 *
 * NOTE: This is an architecture specific function, and should
 *       be hidden from the drivers.
 */
#define clear_dma_ff(channel)

/* Set only the page register bits of the transfer address.
 *
 * NOTE: This is an architecture specific function, and should
 *       be hidden from the drivers
 */
static __inline__ void set_dma_page(dmach_t channel, char pagenr)
{
	printk(dma_str, "set_dma_page", channel);
}

/* Request a DMA channel
 *
 * Some architectures may need to do allocate an interrupt
 */
extern int  request_dma(dmach_t channel, const char * device_id);

/* Free a DMA channel
 *
 * Some architectures may need to do free an interrupt
 */
extern void free_dma(dmach_t channel);

/* Enable DMA for this channel
 *
 * On some architectures, this may have other side effects like
 * enabling an interrupt and setting the DMA registers.
 */
extern void enable_dma(dmach_t channel);

/* Disable DMA for this channel
 *
 * On some architectures, this may have other side effects like
 * disabling an interrupt or whatever.
 */
extern void disable_dma(dmach_t channel);

/* Set the DMA scatter gather list for this channel
 *
 * This should not be called if a DMA channel is enabled,
 * especially since some DMA architectures don't update the
 * DMA address immediately, but defer it to the enable_dma().
 */
extern void set_dma_sg(dmach_t channel, dmasg_t *sg, int nr_sg);

/* Set the DMA address for this channel
 *
 * This should not be called if a DMA channel is enabled,
 * especially since some DMA architectures don't update the
 * DMA address immediately, but defer it to the enable_dma().
 */
extern void set_dma_addr(dmach_t channel, unsigned long physaddr);

/* Set the DMA byte count for this channel
 *
 * This should not be called if a DMA channel is enabled,
 * especially since some DMA architectures don't update the
 * DMA count immediately, but defer it to the enable_dma().
 */
extern void set_dma_count(dmach_t channel, unsigned long count);

/* Set the transfer direction for this channel
 *
 * This should not be called if a DMA channel is enabled,
 * especially since some DMA architectures don't update the
 * DMA transfer direction immediately, but defer it to the
 * enable_dma().
 */
extern void set_dma_mode(dmach_t channel, dmamode_t mode);

/* Get DMA residue count. After a DMA transfer, this
 * should return zero. Reading this while a DMA transfer is
 * still in progress will return unpredictable results.
 * If called before the channel has been used, it may return 1.
 * Otherwise, it returns the number of _bytes_ left to transfer.
 */
extern int  get_dma_residue(dmach_t channel);

#ifndef NO_DMA
#define NO_DMA	255
#endif

#endif /* _ARM_DMA_H */