include/linux/of_dma.h

   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_DMA_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 ERR_PTR(-ENODEV);
  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 */