linux/drivers/dma/dmaengine.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * 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>

/**
 * dma_cookie_init - initialize the cookies for a DMA channel
 * @chan: dma channel to initialize
 */
static inline void dma_cookie_init(struct dma_chan *chan)
{ … }

/**
 * dma_cookie_assign - assign a DMA engine cookie to the descriptor
 * @tx: descriptor needing cookie
 *
 * Assign a unique non-zero per-channel cookie to the descriptor.
 * Note: caller is expected to hold a lock to prevent concurrency.
 */
static inline dma_cookie_t dma_cookie_assign(struct dma_async_tx_descriptor *tx)
{ … }

/**
 * dma_cookie_complete - complete a descriptor
 * @tx: descriptor to complete
 *
 * Mark this descriptor complete by updating the channels completed
 * cookie marker.  Zero the descriptors cookie to prevent accidental
 * repeated completions.
 *
 * Note: caller is expected to hold a lock to prevent concurrency.
 */
static inline void dma_cookie_complete(struct dma_async_tx_descriptor *tx)
{ … }

/**
 * dma_cookie_status - report cookie status
 * @chan: dma channel
 * @cookie: cookie we are interested in
 * @state: dma_tx_state structure to return last/used cookies
 *
 * Report the status of the cookie, filling in the state structure if
 * non-NULL.  No locking is required.
 */
static inline enum dma_status dma_cookie_status(struct dma_chan *chan,
	dma_cookie_t cookie, struct dma_tx_state *state)
{ … }

static inline void dma_set_residue(struct dma_tx_state *state, u32 residue)
{ … }

static inline void dma_set_in_flight_bytes(struct dma_tx_state *state,
					   u32 in_flight_bytes)
{ … }

struct dmaengine_desc_callback { … };

/**
 * dmaengine_desc_get_callback - get the passed in callback function
 * @tx: tx descriptor
 * @cb: temp struct to hold the callback info
 *
 * Fill the passed in cb struct with what's available in the passed in
 * tx descriptor struct
 * No locking is required.
 */
static inline void
dmaengine_desc_get_callback(struct dma_async_tx_descriptor *tx,
			    struct dmaengine_desc_callback *cb)
{ … }

/**
 * dmaengine_desc_callback_invoke - call the callback function in cb struct
 * @cb: temp struct that is holding the callback info
 * @result: transaction result
 *
 * Call the callback function provided in the cb struct with the parameter
 * in the cb struct.
 * Locking is dependent on the driver.
 */
static inline void
dmaengine_desc_callback_invoke(struct dmaengine_desc_callback *cb,
			       const struct dmaengine_result *result)
{ … }

/**
 * dmaengine_desc_get_callback_invoke - get the callback in tx descriptor and
 * 					then immediately call the callback.
 * @tx: dma async tx descriptor
 * @result: transaction result
 *
 * Call dmaengine_desc_get_callback() and dmaengine_desc_callback_invoke()
 * in a single function since no work is necessary in between for the driver.
 * Locking is dependent on the driver.
 */
static inline void
dmaengine_desc_get_callback_invoke(struct dma_async_tx_descriptor *tx,
				   const struct dmaengine_result *result)
{ … }

/**
 * dmaengine_desc_callback_valid - verify the callback is valid in cb
 * @cb: callback info struct
 *
 * Return a bool that verifies whether callback in cb is valid or not.
 * No locking is required.
 */
static inline bool
dmaengine_desc_callback_valid(struct dmaengine_desc_callback *cb)
{ … }

struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);

#ifdef CONFIG_DEBUG_FS
#include <linux/debugfs.h>

static inline struct dentry *
dmaengine_get_debugfs_root(struct dma_device *dma_dev) { … }
#else
struct dentry;
static inline struct dentry *
dmaengine_get_debugfs_root(struct dma_device *dma_dev)
{
	return NULL;
}
#endif /* CONFIG_DEBUG_FS */

#endif