xref: /linux/include/linux/of_dma.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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_route_allocate)
27 				(struct of_phandle_args *, struct of_dma *);
28 	struct dma_router	*dma_router;
29 	void			*of_dma_data;
30 };
31 
32 struct of_dma_filter_info {
33 	dma_cap_mask_t	dma_cap;
34 	dma_filter_fn	filter_fn;
35 };
36 
37 #ifdef CONFIG_OF
38 extern int of_dma_controller_register(struct device_node *np,
39 		struct dma_chan *(*of_dma_xlate)
40 		(struct of_phandle_args *, struct of_dma *),
41 		void *data);
42 extern void of_dma_controller_free(struct device_node *np);
43 
44 extern int of_dma_router_register(struct device_node *np,
45 		void *(*of_dma_route_allocate)
46 		(struct of_phandle_args *, struct of_dma *),
47 		struct dma_router *dma_router);
48 #define of_dma_router_free of_dma_controller_free
49 
50 extern struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
51 						     const char *name);
52 extern struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
53 		struct of_dma *ofdma);
54 extern struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec,
55 		struct of_dma *ofdma);
56 
57 #else
58 static inline int of_dma_controller_register(struct device_node *np,
59 		struct dma_chan *(*of_dma_xlate)
60 		(struct of_phandle_args *, struct of_dma *),
61 		void *data)
62 {
63 	return -ENODEV;
64 }
65 
66 static inline void of_dma_controller_free(struct device_node *np)
67 {
68 }
69 
70 static inline int of_dma_router_register(struct device_node *np,
71 		void *(*of_dma_route_allocate)
72 		(struct of_phandle_args *, struct of_dma *),
73 		struct dma_router *dma_router)
74 {
75 	return -ENODEV;
76 }
77 
78 #define of_dma_router_free of_dma_controller_free
79 
80 static inline struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
81 						     const char *name)
82 {
83 	return NULL;
84 }
85 
86 static inline struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
87 		struct of_dma *ofdma)
88 {
89 	return NULL;
90 }
91 
92 #define of_dma_xlate_by_chan_id NULL
93 
94 #endif
95 
96 #endif /* __LINUX_OF_DMA_H */
97