dmaengine.h

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/*
 * The contents of this file are private to DMA engine drivers, and is not
 * part of the API to be used by DMA engine users.
 */
#ifndef DMAENGINE_H
#define DMAENGINE_H

#include <linux/bug.h>
#include <linux/dmaengine.h>

static inline void dma_cookie_init(struct dma_chan *chan)
{
    chan->cookie = DMA_MIN_COOKIE;
    chan->completed_cookie = DMA_MIN_COOKIE;
}

static inline dma_cookie_t dma_cookie_assign(struct dma_async_tx_descriptor *tx)
{
    struct dma_chan *chan = tx->chan;
    dma_cookie_t cookie;

    cookie = chan->cookie + 1;
    if (cookie < DMA_MIN_COOKIE)
        cookie = DMA_MIN_COOKIE;
    tx->cookie = chan->cookie = cookie;

    return cookie;
}

static inline void dma_cookie_complete(struct dma_async_tx_descriptor *tx)
{
    BUG_ON(tx->cookie < DMA_MIN_COOKIE);
    tx->chan->completed_cookie = tx->cookie;
    tx->cookie = 0;
}

static inline enum dma_status dma_cookie_status(struct dma_chan *chan,
    dma_cookie_t cookie, struct dma_tx_state *state)
{
    dma_cookie_t used, complete;

    used = chan->cookie;
    complete = chan->completed_cookie;
    barrier();
    if (state) {
        state->last = complete;
        state->used = used;
        state->residue = 0;
    }
    return dma_async_is_complete(cookie, complete, used);
}

static inline void dma_set_residue(struct dma_tx_state *state, u32 residue)
{
    if (state)
        state->residue = residue;
}

#endif