include/dm/of.h

   1 /*
   2  * Copyright (c) 2017 Google, Inc
   3  * Written by Simon Glass <sjg@chromium.org>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #ifndef _DM_OF_H
   9 #define _DM_OF_H
  10
  11 #include <asm/u-boot.h>
  12 #include <asm/global_data.h>
  13
  14 /* integer value within a device tree property which references another node */
  15 typedef u32 phandle;
  16
  17 /**
  18  * struct property: Device tree property
  19  *
  20  * @name: Property name
  21  * @length: Length of property in bytes
  22  * @value: Pointer to property value
  23  * @next: Pointer to next property, or NULL if none
  24  */
  25 struct property {
  26         char *name;
  27         int length;
  28         void *value;
  29         struct property *next;
  30 };
  31
  32 /**
  33  * struct device_node: Device tree node
  34  *
  35  * @name: Node name
  36  * @type: Node type (value of device_type property) or "<NULL>" if none
  37  * @phandle: Phandle value of this none, or 0 if none
  38  * @full_name: Full path to node, e.g. "/bus@1/spi@1100"
  39  * @properties: Pointer to head of list of properties, or NULL if none
  40  * @parent: Pointer to parent node, or NULL if this is the root node
  41  * @child: Pointer to head of child node list, or NULL if no children
  42  * @sibling: Pointer to the next sibling node, or NULL if this is the last
  43  */
  44 struct device_node {
  45         const char *name;
  46         const char *type;
  47         phandle phandle;
  48         const char *full_name;
  49
  50         struct property *properties;
  51         struct device_node *parent;
  52         struct device_node *child;
  53         struct device_node *sibling;
  54 };
  55
  56 #define OF_MAX_PHANDLE_ARGS 16
  57
  58 /**
  59  * struct of_phandle_args - structure to hold phandle and arguments
  60  *
  61  * This is used when decoding a phandle in a device tree property. Typically
  62  * these look like this:
  63  *
  64  * wibble {
  65  *    phandle = <5>;
  66  * };
  67  *
  68  * ...
  69  * some-prop = <&wibble 1 2 3>
  70  *
  71  * Here &node is the phandle of the node 'wibble', i.e. 5. There are three
  72  * arguments: 1, 2, 3.
  73  *
  74  * So when decoding the phandle in some-prop, np will point to wibble,
  75  * args_count will be 3 and the three arguments will be in args.
  76  *
  77  * @np: Node that the phandle refers to
  78  * @args_count: Number of arguments
  79  * @args: Argument values
  80  */
  81 struct of_phandle_args {
  82         struct device_node *np;
  83         int args_count;
  84         uint32_t args[OF_MAX_PHANDLE_ARGS];
  85 };
  86
  87 DECLARE_GLOBAL_DATA_PTR;
  88
  89 /**
  90  * of_live_active() - check if livetree is active
  91  *
  92  * @returns true if livetree is active, false it not
  93  */
  94 #ifdef CONFIG_OF_LIVE
  95 static inline bool of_live_active(void)
  96 {
  97         return gd->of_root != NULL;
  98 }
  99 #else
 100 static inline bool of_live_active(void)
 101 {
 102         return false;
 103 }
 104 #endif
 105
 106 #endif