xref: /linux/include/linux/of_dma.h (revision 6eb2fb3170549737207974c2c6ad34bcc2f3025e)
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 	int			of_dma_nbcells;
25 	struct dma_chan		*(*of_dma_xlate)
26 				(struct of_phandle_args *, struct of_dma *);
27 	void			*of_dma_data;
28 };
29 
30 struct of_dma_filter_info {
31 	dma_cap_mask_t	dma_cap;
32 	dma_filter_fn	filter_fn;
33 };
34 
35 #ifdef CONFIG_OF
36 extern int of_dma_controller_register(struct device_node *np,
37 		struct dma_chan *(*of_dma_xlate)
38 		(struct of_phandle_args *, struct of_dma *),
39 		void *data);
40 extern void of_dma_controller_free(struct device_node *np);
41 extern struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
42 						     const char *name);
43 extern struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
44 		struct of_dma *ofdma);
45 #else
46 static inline int of_dma_controller_register(struct device_node *np,
47 		struct dma_chan *(*of_dma_xlate)
48 		(struct of_phandle_args *, struct of_dma *),
49 		void *data)
50 {
51 	return -ENODEV;
52 }
53 
54 static inline void of_dma_controller_free(struct device_node *np)
55 {
56 }
57 
58 static inline struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
59 						     const char *name)
60 {
61 	return NULL;
62 }
63 
64 static inline struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
65 		struct of_dma *ofdma)
66 {
67 	return NULL;
68 }
69 
70 #endif
71 
72 #endif /* __LINUX_OF_DMA_H */
73