xref: /linux/include/linux/of_dma.h (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
1 /*
2  * OF helpers for DMA request / controller
3  *
4  * Based on of_gpio.h
5  *
6  * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #ifndef __LINUX_OF_DMA_H
14 #define __LINUX_OF_DMA_H
15 
16 #include <linux/of.h>
17 #include <linux/dmaengine.h>
18 
19 struct device_node;
20 
21 struct of_dma {
22 	struct list_head	of_dma_controllers;
23 	struct device_node	*of_node;
24 	struct dma_chan		*(*of_dma_xlate)
25 				(struct of_phandle_args *, struct of_dma *);
26 	void			*of_dma_data;
27 };
28 
29 struct of_dma_filter_info {
30 	dma_cap_mask_t	dma_cap;
31 	dma_filter_fn	filter_fn;
32 };
33 
34 #ifdef CONFIG_OF
35 extern int of_dma_controller_register(struct device_node *np,
36 		struct dma_chan *(*of_dma_xlate)
37 		(struct of_phandle_args *, struct of_dma *),
38 		void *data);
39 extern void of_dma_controller_free(struct device_node *np);
40 extern struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
41 						     const char *name);
42 extern struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
43 		struct of_dma *ofdma);
44 #else
45 static inline int of_dma_controller_register(struct device_node *np,
46 		struct dma_chan *(*of_dma_xlate)
47 		(struct of_phandle_args *, struct of_dma *),
48 		void *data)
49 {
50 	return -ENODEV;
51 }
52 
53 static inline void of_dma_controller_free(struct device_node *np)
54 {
55 }
56 
57 static inline struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
58 						     const char *name)
59 {
60 	return NULL;
61 }
62 
63 static inline struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
64 		struct of_dma *ofdma)
65 {
66 	return NULL;
67 }
68 
69 #endif
70 
71 #endif /* __LINUX_OF_DMA_H */
72