1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * OF helpers for DMA request / controller
4  *
5  * Based on of_gpio.h
6  *
7  * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
8  */
9 
10 #ifndef __LINUX_OF_DMA_H
11 #define __LINUX_OF_DMA_H
12 
13 #include <linux/of.h>
14 #include <linux/dmaengine.h>
15 
16 struct device_node;
17 
18 struct of_dma {
19 	struct list_head	of_dma_controllers;
20 	struct device_node	*of_node;
21 	struct dma_chan		*(*of_dma_xlate)
22 				(struct of_phandle_args *, struct of_dma *);
23 	void			*(*of_dma_route_allocate)
24 				(struct of_phandle_args *, struct of_dma *);
25 	struct dma_router	*dma_router;
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_DMA_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 
41 extern int of_dma_router_register(struct device_node *np,
42 		void *(*of_dma_route_allocate)
43 		(struct of_phandle_args *, struct of_dma *),
44 		struct dma_router *dma_router);
45 #define of_dma_router_free of_dma_controller_free
46 
47 extern struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
48 						     const char *name);
49 extern struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
50 		struct of_dma *ofdma);
51 extern struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec,
52 		struct of_dma *ofdma);
53 
54 #else
of_dma_controller_register(struct device_node * np,struct dma_chan * (* of_dma_xlate)(struct of_phandle_args *,struct of_dma *),void * data)55 static inline int of_dma_controller_register(struct device_node *np,
56 		struct dma_chan *(*of_dma_xlate)
57 		(struct of_phandle_args *, struct of_dma *),
58 		void *data)
59 {
60 	return -ENODEV;
61 }
62 
of_dma_controller_free(struct device_node * np)63 static inline void of_dma_controller_free(struct device_node *np)
64 {
65 }
66 
of_dma_router_register(struct device_node * np,void * (* of_dma_route_allocate)(struct of_phandle_args *,struct of_dma *),struct dma_router * dma_router)67 static inline int of_dma_router_register(struct device_node *np,
68 		void *(*of_dma_route_allocate)
69 		(struct of_phandle_args *, struct of_dma *),
70 		struct dma_router *dma_router)
71 {
72 	return -ENODEV;
73 }
74 
75 #define of_dma_router_free of_dma_controller_free
76 
of_dma_request_slave_channel(struct device_node * np,const char * name)77 static inline struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
78 						     const char *name)
79 {
80 	return ERR_PTR(-ENODEV);
81 }
82 
of_dma_simple_xlate(struct of_phandle_args * dma_spec,struct of_dma * ofdma)83 static inline struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
84 		struct of_dma *ofdma)
85 {
86 	return NULL;
87 }
88 
89 #define of_dma_xlate_by_chan_id NULL
90 
91 #endif
92 
93 #endif /* __LINUX_OF_DMA_H */
94