/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __OF_RESERVED_MEM_H
#define __OF_RESERVED_MEM_H

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

struct of_phandle_args;
struct reserved_mem_ops;
struct resource;

struct reserved_mem {
        const char                      *name;
        unsigned long                   fdt_node;
        const struct reserved_mem_ops   *ops;
        phys_addr_t                     base;
        phys_addr_t                     size;
        void                            *priv;
};

struct reserved_mem_ops {
        int     (*device_init)(struct reserved_mem *rmem,
                               struct device *dev);
        void    (*device_release)(struct reserved_mem *rmem,
                                  struct device *dev);
};

typedef int (*reservedmem_of_init_fn)(struct reserved_mem *rmem);

#ifdef CONFIG_OF_RESERVED_MEM

#define RESERVEDMEM_OF_DECLARE(name, compat, init)                      \
        _OF_DECLARE(reservedmem, name, compat, init, reservedmem_of_init_fn)

int of_reserved_mem_device_init_by_idx(struct device *dev,
                                       struct device_node *np, int idx);
int of_reserved_mem_device_init_by_name(struct device *dev,
                                        struct device_node *np,
                                        const char *name);
void of_reserved_mem_device_release(struct device *dev);

struct reserved_mem *of_reserved_mem_lookup(struct device_node *np);
int of_reserved_mem_region_to_resource(const struct device_node *np,
                                       unsigned int idx, struct resource *res);
int of_reserved_mem_region_to_resource_byname(const struct device_node *np,
                                              const char *name, struct resource *res);
int of_reserved_mem_region_count(const struct device_node *np);

#else

#define RESERVEDMEM_OF_DECLARE(name, compat, init)                      \
        _OF_DECLARE_STUB(reservedmem, name, compat, init, reservedmem_of_init_fn)

static inline int of_reserved_mem_device_init_by_idx(struct device *dev,
                                        struct device_node *np, int idx)
{
        return -ENOSYS;
}

static inline int of_reserved_mem_device_init_by_name(struct device *dev,
                                                      struct device_node *np,
                                                      const char *name)
{
        return -ENOSYS;
}

static inline void of_reserved_mem_device_release(struct device *pdev) { }

static inline struct reserved_mem *of_reserved_mem_lookup(struct device_node *np)
{
        return NULL;
}

static inline int of_reserved_mem_region_to_resource(const struct device_node *np,
                                                     unsigned int idx,
                                                     struct resource *res)
{
        return -ENOSYS;
}

static inline int of_reserved_mem_region_to_resource_byname(const struct device_node *np,
                                                            const char *name,
                                                            struct resource *res)
{
        return -ENOSYS;
}

static inline int of_reserved_mem_region_count(const struct device_node *np)
{
        return 0;
}
#endif

/**
 * of_reserved_mem_device_init() - assign reserved memory region to given device
 * @dev:        Pointer to the device to configure
 *
 * This function assigns respective DMA-mapping operations based on the first
 * reserved memory region specified by 'memory-region' property in device tree
 * node of the given device.
 *
 * Returns error code or zero on success.
 */
static inline int of_reserved_mem_device_init(struct device *dev)
{
        return of_reserved_mem_device_init_by_idx(dev, dev->of_node, 0);
}

#endif /* __OF_RESERVED_MEM_H */