/*
* ACPI helpers for DMA request / controller
*
* Based on of_dma.h
*
* Copyright (C) 2013, Intel Corporation
* Author: Andy Shevchenko <[email protected]>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/

#ifndef __LINUX_ACPI_DMA_H
#define __LINUX_ACPI_DMA_H

#include <linux/list.h>
#include <linux/device.h>
#include <linux/dmaengine.h>

/**
* struct acpi_dma_spec - slave device DMA resources
* @chan_id: channel unique id
* @slave_id: request line unique id
* @dev: struct device of the DMA controller to be used in the filter
* function
*/
struct acpi_dma_spec {
int chan_id;
int slave_id;
struct device *dev;
};

/**
* struct acpi_dma - representation of the registered DMAC
* @dma_controllers: linked list node
* @dev: struct device of this controller
* @acpi_dma_xlate: callback function to find a suitable channel
* @data: private data used by a callback function
* @base_request_line: first supported request line (CSRT)
* @end_request_line: last supported request line (CSRT)
*/
struct acpi_dma {
struct list_head dma_controllers;
struct device *dev;
struct dma_chan *(*acpi_dma_xlate)
(struct acpi_dma_spec *, struct acpi_dma *);
void *data;
unsigned short base_request_line;
unsigned short end_request_line;
};

/* Used with acpi_dma_simple_xlate() */
struct acpi_dma_filter_info {
dma_cap_mask_t dma_cap;
dma_filter_fn filter_fn;
};

#ifdef CONFIG_DMA_ACPI

int acpi_dma_controller_register(struct device *dev,
struct dma_chan *(*acpi_dma_xlate)
(struct acpi_dma_spec *, struct acpi_dma *),
void *data);
int acpi_dma_controller_free(struct device *dev);
int devm_acpi_dma_controller_register(struct device *dev,
struct dma_chan *(*acpi_dma_xlate)
(struct acpi_dma_spec *, struct acpi_dma *),
void *data);
void devm_acpi_dma_controller_free(struct device *dev);

struct dma_chan *acpi_dma_request_slave_chan_by_index(struct device *dev,
size_t index);
struct dma_chan *acpi_dma_request_slave_chan_by_name(struct device *dev,
const char *name);

struct dma_chan *acpi_dma_simple_xlate(struct acpi_dma_spec *dma_spec,
struct acpi_dma *adma);
#else

static inline int acpi_dma_controller_register(struct device *dev,
struct dma_chan *(*acpi_dma_xlate)
(struct acpi_dma_spec *, struct acpi_dma *),
void *data)
{
return -ENODEV;
}
static inline int acpi_dma_controller_free(struct device *dev)
{
return -ENODEV;
}
static inline int devm_acpi_dma_controller_register(struct device *dev,
struct dma_chan *(*acpi_dma_xlate)
(struct acpi_dma_spec *, struct acpi_dma *),
void *data)
{
return -ENODEV;
}
static inline void devm_acpi_dma_controller_free(struct device *dev)
{
}

static inline struct dma_chan *acpi_dma_request_slave_chan_by_index(
struct device *dev, size_t index)
{
return NULL;
}
static inline struct dma_chan *acpi_dma_request_slave_chan_by_name(
struct device *dev, const char *name)
{
return NULL;
}

#define acpi_dma_simple_xlate NULL

#endif

#define acpi_dma_request_slave_channel acpi_dma_request_slave_chan_by_index

#endif /* __LINUX_ACPI_DMA_H */