root/include/linux/of_dma.h
/* SPDX-License-Identifier: GPL-2.0 */
/*
 * OF helpers for DMA request / controller
 *
 * Based on of_gpio.h
 *
 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
 */

#ifndef __LINUX_OF_DMA_H
#define __LINUX_OF_DMA_H

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

struct device_node;

struct of_dma {
        struct list_head        of_dma_controllers;
        struct device_node      *of_node;
        struct dma_chan         *(*of_dma_xlate)
                                (struct of_phandle_args *, struct of_dma *);
        void                    *(*of_dma_route_allocate)
                                (struct of_phandle_args *, struct of_dma *);
        struct dma_router       *dma_router;
        void                    *of_dma_data;
};

struct of_dma_filter_info {
        dma_cap_mask_t  dma_cap;
        dma_filter_fn   filter_fn;
};

#ifdef CONFIG_DMA_OF
extern int of_dma_controller_register(struct device_node *np,
                struct dma_chan *(*of_dma_xlate)
                (struct of_phandle_args *, struct of_dma *),
                void *data);
extern void of_dma_controller_free(struct device_node *np);

extern int of_dma_router_register(struct device_node *np,
                void *(*of_dma_route_allocate)
                (struct of_phandle_args *, struct of_dma *),
                struct dma_router *dma_router);
#define of_dma_router_free of_dma_controller_free

extern struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
                                                     const char *name);
extern struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
                struct of_dma *ofdma);
extern struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec,
                struct of_dma *ofdma);

#else
static inline int of_dma_controller_register(struct device_node *np,
                struct dma_chan *(*of_dma_xlate)
                (struct of_phandle_args *, struct of_dma *),
                void *data)
{
        return -ENODEV;
}

static inline void of_dma_controller_free(struct device_node *np)
{
}

static inline int of_dma_router_register(struct device_node *np,
                void *(*of_dma_route_allocate)
                (struct of_phandle_args *, struct of_dma *),
                struct dma_router *dma_router)
{
        return -ENODEV;
}

#define of_dma_router_free of_dma_controller_free

static inline struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
                                                     const char *name)
{
        return ERR_PTR(-ENODEV);
}

static inline struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
                struct of_dma *ofdma)
{
        return NULL;
}

#define of_dma_xlate_by_chan_id NULL

#endif

#endif /* __LINUX_OF_DMA_H */