| 1 | /* |
| 2 | * arch/ubicom32/kernel/devtree.c |
| 3 | * Ubicom32 architecture device tree implementation. |
| 4 | * |
| 5 | * (C) Copyright 2009, Ubicom, Inc. |
| 6 | * |
| 7 | * This file is part of the Ubicom32 Linux Kernel Port. |
| 8 | * |
| 9 | * The Ubicom32 Linux Kernel Port is free software: you can redistribute |
| 10 | * it and/or modify it under the terms of the GNU General Public License |
| 11 | * as published by the Free Software Foundation, either version 2 of the |
| 12 | * License, or (at your option) any later version. |
| 13 | * |
| 14 | * The Ubicom32 Linux Kernel Port is distributed in the hope that it |
| 15 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
| 16 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 17 | * the GNU General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU General Public License |
| 20 | * along with the Ubicom32 Linux Kernel Port. If not, |
| 21 | * see <http://www.gnu.org/licenses/>. |
| 22 | * |
| 23 | * Ubicom32 implementation derived from (with many thanks): |
| 24 | * arch/m68knommu |
| 25 | * arch/blackfin |
| 26 | * arch/parisc |
| 27 | */ |
| 28 | |
| 29 | #include <linux/module.h> |
| 30 | #include <linux/kernel.h> |
| 31 | #include <linux/string.h> |
| 32 | #include <linux/errno.h> |
| 33 | #include <asm/devtree.h> |
| 34 | |
| 35 | /* |
| 36 | * The device tree. |
| 37 | */ |
| 38 | struct devtree_node *devtree; |
| 39 | |
| 40 | /* |
| 41 | * devtree_print() |
| 42 | * Print the device tree. |
| 43 | */ |
| 44 | void devtree_print(void) |
| 45 | { |
| 46 | struct devtree_node *p = devtree; |
| 47 | printk(KERN_INFO "Device Tree:\n"); |
| 48 | while (p) { |
| 49 | if (p->magic != DEVTREE_NODE_MAGIC) { |
| 50 | printk(KERN_EMERG |
| 51 | "device tree has improper node: %p\n", p); |
| 52 | return; |
| 53 | } |
| 54 | printk(KERN_INFO "\t%p: sendirq=%03d, recvirq=%03d, " |
| 55 | " name=%s\n", p, p->sendirq, p->recvirq, p->name); |
| 56 | p = p->next; |
| 57 | } |
| 58 | } |
| 59 | EXPORT_SYMBOL(devtree_print); |
| 60 | |
| 61 | /* |
| 62 | * devtree_irq() |
| 63 | * Return the IRQ(s) associated with devtree node. |
| 64 | */ |
| 65 | int devtree_irq(struct devtree_node *dn, |
| 66 | unsigned char *sendirq, |
| 67 | unsigned char *recvirq) |
| 68 | { |
| 69 | if (dn->magic != DEVTREE_NODE_MAGIC) { |
| 70 | printk(KERN_EMERG "improper node: %p\n", dn); |
| 71 | if (sendirq) { |
| 72 | *sendirq = DEVTREE_IRQ_NONE; |
| 73 | } |
| 74 | if (recvirq) { |
| 75 | *recvirq = DEVTREE_IRQ_NONE; |
| 76 | } |
| 77 | return -EFAULT; |
| 78 | } |
| 79 | |
| 80 | /* |
| 81 | * Copy the devtree irq(s) to the output parameters. |
| 82 | */ |
| 83 | if (sendirq) { |
| 84 | *sendirq = dn->sendirq; |
| 85 | } |
| 86 | if (recvirq) { |
| 87 | *recvirq = dn->recvirq; |
| 88 | } |
| 89 | return 0; |
| 90 | } |
| 91 | EXPORT_SYMBOL(devtree_irq); |
| 92 | |
| 93 | /* |
| 94 | * devtree_find_next() |
| 95 | * Provide an iterator for walking the device tree. |
| 96 | */ |
| 97 | struct devtree_node *devtree_find_next(struct devtree_node **cur) |
| 98 | { |
| 99 | struct devtree_node *p = *cur; |
| 100 | if (!p) { |
| 101 | *cur = devtree; |
| 102 | return devtree; |
| 103 | } |
| 104 | p = p->next; |
| 105 | *cur = p; |
| 106 | return p; |
| 107 | } |
| 108 | |
| 109 | /* |
| 110 | * devtree_find_by_irq() |
| 111 | * Return the node associated with a given irq. |
| 112 | */ |
| 113 | struct devtree_node *devtree_find_by_irq(uint8_t sendirq, uint8_t recvirq) |
| 114 | { |
| 115 | struct devtree_node *p = devtree; |
| 116 | |
| 117 | if (sendirq == recvirq) { |
| 118 | printk(KERN_EMERG "identical request makes no sense sendirq = " |
| 119 | "%d, recvirq= %d\n", sendirq, recvirq); |
| 120 | return NULL; |
| 121 | } |
| 122 | |
| 123 | while (p) { |
| 124 | if (p->magic != DEVTREE_NODE_MAGIC) { |
| 125 | printk(KERN_EMERG |
| 126 | "device tree has improper node: %p\n", p); |
| 127 | return NULL; |
| 128 | } |
| 129 | |
| 130 | /* |
| 131 | * See if we can find a match on the IRQ(s) specified. |
| 132 | */ |
| 133 | if ((sendirq == p->sendirq) && (recvirq == p->recvirq)) { |
| 134 | return p; |
| 135 | } |
| 136 | |
| 137 | if ((sendirq == DEVTREE_IRQ_DONTCARE) && |
| 138 | (p->recvirq == recvirq)) { |
| 139 | return p; |
| 140 | } |
| 141 | |
| 142 | if ((recvirq == DEVTREE_IRQ_DONTCARE) && |
| 143 | (p->sendirq == sendirq)) { |
| 144 | return p; |
| 145 | } |
| 146 | |
| 147 | p = p->next; |
| 148 | } |
| 149 | return NULL; |
| 150 | } |
| 151 | EXPORT_SYMBOL(devtree_find_by_irq); |
| 152 | |
| 153 | /* |
| 154 | * devtree_find_node() |
| 155 | * Find a node in the device tree by name. |
| 156 | */ |
| 157 | struct devtree_node *devtree_find_node(const char *str) |
| 158 | { |
| 159 | struct devtree_node *p = devtree; |
| 160 | while (p) { |
| 161 | if (p->magic != DEVTREE_NODE_MAGIC) { |
| 162 | printk(KERN_EMERG |
| 163 | "device tree has improper node: %p\n", p); |
| 164 | return NULL; |
| 165 | } |
| 166 | if (strcmp(p->name, str) == 0) { |
| 167 | return p; |
| 168 | } |
| 169 | p = p->next; |
| 170 | } |
| 171 | return NULL; |
| 172 | } |
| 173 | EXPORT_SYMBOL(devtree_find_node); |
| 174 | |
