/* * ACPI helpers for DMA request / controller * * Based on of_dma.h * * Copyright (C) 2013, Intel Corporation * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com> * * 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/err.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 ERR_PTR(-ENODEV); } static inline struct dma_chan *acpi_dma_request_slave_chan_by_name( struct device *dev, const char *name) { return ERR_PTR(-ENODEV); } #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 */