shdma-base.h

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/*
 * Dmaengine driver base library for DMA controllers, found on SH-based SoCs
 *
 * extracted from shdma.c and headers
 *
 * Copyright (C) 2011-2012 Guennadi Liakhovetski <[email protected]>
 * Copyright (C) 2009 Nobuhiro Iwamatsu <[email protected]>
 * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
 * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
 *
 * This is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 */

#ifndef SHDMA_BASE_H
#define SHDMA_BASE_H

#include <linux/dmaengine.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/types.h>

enum shdma_pm_state {
    SHDMA_PM_ESTABLISHED,
    SHDMA_PM_BUSY,
    SHDMA_PM_PENDING,
};

struct device;

/*
 * Drivers, using this library are expected to embed struct shdma_dev,
 * struct shdma_chan, struct shdma_desc, and struct shdma_slave
 * in their respective device, channel, descriptor and slave objects.
 */

struct shdma_slave {
    int slave_id;
};

struct shdma_desc {
    struct list_head node;
    struct dma_async_tx_descriptor async_tx;
    enum dma_transfer_direction direction;
    size_t partial;
    dma_cookie_t cookie;
    int chunks;
    int mark;
};

struct shdma_chan {
    spinlock_t chan_lock;       /* Channel operation lock */
    struct list_head ld_queue;  /* Link descriptors queue */
    struct list_head ld_free;   /* Free link descriptors */
    struct dma_chan dma_chan;   /* DMA channel */
    struct device *dev;     /* Channel device */
    void *desc;         /* buffer for descriptor array */
    int desc_num;           /* desc count */
    size_t max_xfer_len;        /* max transfer length */
    int id;             /* Raw id of this channel */
    int irq;            /* Channel IRQ */
    int slave_id;           /* Client ID for slave DMA */
    enum shdma_pm_state pm_state;
};

struct shdma_ops {
    bool (*desc_completed)(struct shdma_chan *, struct shdma_desc *);
    void (*halt_channel)(struct shdma_chan *);
    bool (*channel_busy)(struct shdma_chan *);
    dma_addr_t (*slave_addr)(struct shdma_chan *);
    int (*desc_setup)(struct shdma_chan *, struct shdma_desc *,
              dma_addr_t, dma_addr_t, size_t *);
    int (*set_slave)(struct shdma_chan *, int, bool);
    void (*setup_xfer)(struct shdma_chan *, int);
    void (*start_xfer)(struct shdma_chan *, struct shdma_desc *);
    struct shdma_desc *(*embedded_desc)(void *, int);
    bool (*chan_irq)(struct shdma_chan *, int);
    size_t (*get_partial)(struct shdma_chan *, struct shdma_desc *);
};

struct shdma_dev {
    struct dma_device dma_dev;
    struct shdma_chan **schan;
    const struct shdma_ops *ops;
    size_t desc_size;
};

#define shdma_for_each_chan(c, d, i) for (i = 0, c = (d)->schan[0]; \
                i < (d)->dma_dev.chancnt; c = (d)->schan[++i])

int shdma_request_irq(struct shdma_chan *, int,
               unsigned long, const char *);
void shdma_free_irq(struct shdma_chan *);
bool shdma_reset(struct shdma_dev *sdev);
void shdma_chan_probe(struct shdma_dev *sdev,
               struct shdma_chan *schan, int id);
void shdma_chan_remove(struct shdma_chan *schan);
int shdma_init(struct device *dev, struct shdma_dev *sdev,
            int chan_num);
void shdma_cleanup(struct shdma_dev *sdev);

#endif