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_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 extern struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec,
  45                 struct of_dma *ofdma);
  46 #else
  47 static inline int of_dma_controller_register(struct device_node *np,
  48                 struct dma_chan *(*of_dma_xlate)
  49                 (struct of_phandle_args *, struct of_dma *),
  50                 void *data)
  51 {
  52         return -ENODEV;
  53 }
  54
  55 static inline void of_dma_controller_free(struct device_node *np)
  56 {
  57 }
  58
  59 static inline struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
  60                                                      const char *name)
  61 {
  62         return NULL;
  63 }
  64
  65 static inline struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
  66                 struct of_dma *ofdma)
  67 {
  68         return NULL;
  69 }
  70
  71 #define of_dma_xlate_by_chan_id NULL
  72
  73 #endif
  74
  75 #endif /* __LINUX_OF_DMA_H */