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1/* SPDX-License-Identifier: GPL-2.0-only */2/*3 * ACPI helpers for DMA request / controller4 *5 * Based on of_dma.h6 *7 * Copyright (C) 2013, Intel Corporation8 * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>9 */10 11#ifndef __LINUX_ACPI_DMA_H12#define __LINUX_ACPI_DMA_H13 14#include <linux/list.h>15#include <linux/device.h>16#include <linux/err.h>17#include <linux/dmaengine.h>18 19/**20 * struct acpi_dma_spec - slave device DMA resources21 * @chan_id: channel unique id22 * @slave_id: request line unique id23 * @dev: struct device of the DMA controller to be used in the filter24 * function25 */26struct acpi_dma_spec {27 int chan_id;28 int slave_id;29 struct device *dev;30};31 32/**33 * struct acpi_dma - representation of the registered DMAC34 * @dma_controllers: linked list node35 * @dev: struct device of this controller36 * @acpi_dma_xlate: callback function to find a suitable channel37 * @data: private data used by a callback function38 * @base_request_line: first supported request line (CSRT)39 * @end_request_line: last supported request line (CSRT)40 */41struct acpi_dma {42 struct list_head dma_controllers;43 struct device *dev;44 struct dma_chan *(*acpi_dma_xlate)45 (struct acpi_dma_spec *, struct acpi_dma *);46 void *data;47 unsigned short base_request_line;48 unsigned short end_request_line;49};50 51/* Used with acpi_dma_simple_xlate() */52struct acpi_dma_filter_info {53 dma_cap_mask_t dma_cap;54 dma_filter_fn filter_fn;55};56 57#ifdef CONFIG_DMA_ACPI58 59int acpi_dma_controller_register(struct device *dev,60 struct dma_chan *(*acpi_dma_xlate)61 (struct acpi_dma_spec *, struct acpi_dma *),62 void *data);63int acpi_dma_controller_free(struct device *dev);64int devm_acpi_dma_controller_register(struct device *dev,65 struct dma_chan *(*acpi_dma_xlate)66 (struct acpi_dma_spec *, struct acpi_dma *),67 void *data);68void devm_acpi_dma_controller_free(struct device *dev);69 70struct dma_chan *acpi_dma_request_slave_chan_by_index(struct device *dev,71 size_t index);72struct dma_chan *acpi_dma_request_slave_chan_by_name(struct device *dev,73 const char *name);74 75struct dma_chan *acpi_dma_simple_xlate(struct acpi_dma_spec *dma_spec,76 struct acpi_dma *adma);77#else78 79static inline int acpi_dma_controller_register(struct device *dev,80 struct dma_chan *(*acpi_dma_xlate)81 (struct acpi_dma_spec *, struct acpi_dma *),82 void *data)83{84 return -ENODEV;85}86static inline int acpi_dma_controller_free(struct device *dev)87{88 return -ENODEV;89}90static inline int devm_acpi_dma_controller_register(struct device *dev,91 struct dma_chan *(*acpi_dma_xlate)92 (struct acpi_dma_spec *, struct acpi_dma *),93 void *data)94{95 return -ENODEV;96}97static inline void devm_acpi_dma_controller_free(struct device *dev)98{99}100 101static inline struct dma_chan *acpi_dma_request_slave_chan_by_index(102 struct device *dev, size_t index)103{104 return ERR_PTR(-ENODEV);105}106static inline struct dma_chan *acpi_dma_request_slave_chan_by_name(107 struct device *dev, const char *name)108{109 return ERR_PTR(-ENODEV);110}111 112#define acpi_dma_simple_xlate NULL113 114#endif115 116#define acpi_dma_request_slave_channel acpi_dma_request_slave_chan_by_index117 118#endif /* __LINUX_ACPI_DMA_H */119