dma.h

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/*
 * include/asm-sh/dma.h
 *
 * Copyright (C) 2003, 2004  Paul Mundt
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#ifndef __ASM_SH_DMA_H
#define __ASM_SH_DMA_H
#ifdef __KERNEL__

#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/device.h>
#include <asm-generic/dma.h>

/*
 * Read and write modes can mean drastically different things depending on the
 * channel configuration. Consult your DMAC documentation and module
 * implementation for further clues.
 */
#define DMA_MODE_READ       0x00
#define DMA_MODE_WRITE      0x01
#define DMA_MODE_MASK       0x01

#define DMA_AUTOINIT        0x10

/*
 * DMAC (dma_info) flags
 */
enum {
    DMAC_CHANNELS_CONFIGURED    = 0x01,
    DMAC_CHANNELS_TEI_CAPABLE   = 0x02, /* Transfer end interrupt */
};

/*
 * DMA channel capabilities / flags
 */
enum {
    DMA_CONFIGURED          = 0x01,

    /*
     * Transfer end interrupt, inherited from DMAC.
     * wait_queue used in dma_wait_for_completion.
     */
    DMA_TEI_CAPABLE         = 0x02,
};

extern spinlock_t dma_spin_lock;

struct dma_channel;

struct dma_ops {
    int (*request)(struct dma_channel *chan);
    void (*free)(struct dma_channel *chan);

    int (*get_residue)(struct dma_channel *chan);
    int (*xfer)(struct dma_channel *chan);
    int (*configure)(struct dma_channel *chan, unsigned long flags);
    int (*extend)(struct dma_channel *chan, unsigned long op, void *param);
};

struct dma_channel {
    char dev_id[16];        /* unique name per DMAC of channel */

    unsigned int chan;      /* DMAC channel number */
    unsigned int vchan;     /* Virtual channel number */

    unsigned int mode;
    unsigned int count;

    unsigned long sar;
    unsigned long dar;

    const char **caps;

    unsigned long flags;
    atomic_t busy;

    wait_queue_head_t wait_queue;

    struct device dev;
    void *priv_data;
};

struct dma_info {
    struct platform_device *pdev;

    const char *name;
    unsigned int nr_channels;
    unsigned long flags;

    struct dma_ops *ops;
    struct dma_channel *channels;

    struct list_head list;
    int first_channel_nr;
    int first_vchannel_nr;
};

struct dma_chan_caps {
    int ch_num;
    const char **caplist;
};

#define to_dma_channel(channel) container_of(channel, struct dma_channel, dev)

/* arch/sh/drivers/dma/dma-api.c */
extern int dma_xfer(unsigned int chan, unsigned long from,
            unsigned long to, size_t size, unsigned int mode);

#define dma_write(chan, from, to, size) \
    dma_xfer(chan, from, to, size, DMA_MODE_WRITE)
#define dma_write_page(chan, from, to)  \
    dma_write(chan, from, to, PAGE_SIZE)

#define dma_read(chan, from, to, size)  \
    dma_xfer(chan, from, to, size, DMA_MODE_READ)
#define dma_read_page(chan, from, to)   \
    dma_read(chan, from, to, PAGE_SIZE)

extern int request_dma_bycap(const char **dmac, const char **caps,
                 const char *dev_id);
extern int get_dma_residue(unsigned int chan);
extern struct dma_info *get_dma_info(unsigned int chan);
extern struct dma_channel *get_dma_channel(unsigned int chan);
extern void dma_wait_for_completion(unsigned int chan);
extern void dma_configure_channel(unsigned int chan, unsigned long flags);

extern int register_dmac(struct dma_info *info);
extern void unregister_dmac(struct dma_info *info);
extern struct dma_info *get_dma_info_by_name(const char *dmac_name);

extern int dma_extend(unsigned int chan, unsigned long op, void *param);
extern int register_chan_caps(const char *dmac, struct dma_chan_caps *capslist);

/* arch/sh/drivers/dma/dma-sysfs.c */
extern int dma_create_sysfs_files(struct dma_channel *, struct dma_info *);
extern void dma_remove_sysfs_files(struct dma_channel *, struct dma_info *);

#ifdef CONFIG_PCI
extern int isa_dma_bridge_buggy;
#else
#define isa_dma_bridge_buggy    (0)
#endif

#endif /* __KERNEL__ */
#endif /* __ASM_SH_DMA_H */