1 /* 2 * Link physical devices with ACPI devices support 3 * 4 * Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com> 5 * Copyright (c) 2005 Intel Corp. 6 * 7 * This file is released under the GPLv2. 8 */ 9 #include <linux/export.h> 10 #include <linux/init.h> 11 #include <linux/list.h> 12 #include <linux/device.h> 13 #include <linux/slab.h> 14 #include <linux/rwsem.h> 15 #include <linux/acpi.h> 16 17 #include "internal.h" 18 19 #define ACPI_GLUE_DEBUG 0 20 #if ACPI_GLUE_DEBUG 21 #define DBG(fmt, ...) \ 22 printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__) 23 #else 24 #define DBG(fmt, ...) \ 25 do { \ 26 if (0) \ 27 printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__); \ 28 } while (0) 29 #endif 30 static LIST_HEAD(bus_type_list); 31 static DECLARE_RWSEM(bus_type_sem); 32 33 #define PHYSICAL_NODE_STRING "physical_node" 34 35 int register_acpi_bus_type(struct acpi_bus_type *type) 36 { 37 if (acpi_disabled) 38 return -ENODEV; 39 if (type && type->match && type->find_device) { 40 down_write(&bus_type_sem); 41 list_add_tail(&type->list, &bus_type_list); 42 up_write(&bus_type_sem); 43 printk(KERN_INFO PREFIX "bus type %s registered\n", type->name); 44 return 0; 45 } 46 return -ENODEV; 47 } 48 EXPORT_SYMBOL_GPL(register_acpi_bus_type); 49 50 int unregister_acpi_bus_type(struct acpi_bus_type *type) 51 { 52 if (acpi_disabled) 53 return 0; 54 if (type) { 55 down_write(&bus_type_sem); 56 list_del_init(&type->list); 57 up_write(&bus_type_sem); 58 printk(KERN_INFO PREFIX "bus type %s unregistered\n", 59 type->name); 60 return 0; 61 } 62 return -ENODEV; 63 } 64 EXPORT_SYMBOL_GPL(unregister_acpi_bus_type); 65 66 static struct acpi_bus_type *acpi_get_bus_type(struct device *dev) 67 { 68 struct acpi_bus_type *tmp, *ret = NULL; 69 70 down_read(&bus_type_sem); 71 list_for_each_entry(tmp, &bus_type_list, list) { 72 if (tmp->match(dev)) { 73 ret = tmp; 74 break; 75 } 76 } 77 up_read(&bus_type_sem); 78 return ret; 79 } 80 81 static acpi_status do_acpi_find_child(acpi_handle handle, u32 lvl_not_used, 82 void *addr_p, void **ret_p) 83 { 84 unsigned long long addr; 85 acpi_status status; 86 87 status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &addr); 88 if (ACPI_SUCCESS(status) && addr == *((u64 *)addr_p)) { 89 *ret_p = handle; 90 return AE_CTRL_TERMINATE; 91 } 92 return AE_OK; 93 } 94 95 acpi_handle acpi_get_child(acpi_handle parent, u64 address) 96 { 97 void *ret = NULL; 98 99 if (!parent) 100 return NULL; 101 102 acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, 1, NULL, 103 do_acpi_find_child, &address, &ret); 104 return (acpi_handle)ret; 105 } 106 EXPORT_SYMBOL(acpi_get_child); 107 108 static int acpi_bind_one(struct device *dev, acpi_handle handle) 109 { 110 struct acpi_device *acpi_dev; 111 acpi_status status; 112 struct acpi_device_physical_node *physical_node, *pn; 113 char physical_node_name[sizeof(PHYSICAL_NODE_STRING) + 2]; 114 int retval = -EINVAL; 115 116 if (ACPI_HANDLE(dev)) { 117 if (handle) { 118 dev_warn(dev, "ACPI handle is already set\n"); 119 return -EINVAL; 120 } else { 121 handle = ACPI_HANDLE(dev); 122 } 123 } 124 if (!handle) 125 return -EINVAL; 126 127 get_device(dev); 128 status = acpi_bus_get_device(handle, &acpi_dev); 129 if (ACPI_FAILURE(status)) 130 goto err; 131 132 physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL); 133 if (!physical_node) { 134 retval = -ENOMEM; 135 goto err; 136 } 137 138 mutex_lock(&acpi_dev->physical_node_lock); 139 140 /* Sanity check. */ 141 list_for_each_entry(pn, &acpi_dev->physical_node_list, node) 142 if (pn->dev == dev) { 143 dev_warn(dev, "Already associated with ACPI node\n"); 144 goto err_free; 145 } 146 147 /* allocate physical node id according to physical_node_id_bitmap */ 148 physical_node->node_id = 149 find_first_zero_bit(acpi_dev->physical_node_id_bitmap, 150 ACPI_MAX_PHYSICAL_NODE); 151 if (physical_node->node_id >= ACPI_MAX_PHYSICAL_NODE) { 152 retval = -ENOSPC; 153 goto err_free; 154 } 155 156 set_bit(physical_node->node_id, acpi_dev->physical_node_id_bitmap); 157 physical_node->dev = dev; 158 list_add_tail(&physical_node->node, &acpi_dev->physical_node_list); 159 acpi_dev->physical_node_count++; 160 161 mutex_unlock(&acpi_dev->physical_node_lock); 162 163 if (!ACPI_HANDLE(dev)) 164 ACPI_HANDLE_SET(dev, acpi_dev->handle); 165 166 if (!physical_node->node_id) 167 strcpy(physical_node_name, PHYSICAL_NODE_STRING); 168 else 169 sprintf(physical_node_name, 170 "physical_node%d", physical_node->node_id); 171 retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj, 172 physical_node_name); 173 retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj, 174 "firmware_node"); 175 176 if (acpi_dev->wakeup.flags.valid) 177 device_set_wakeup_capable(dev, true); 178 179 return 0; 180 181 err: 182 ACPI_HANDLE_SET(dev, NULL); 183 put_device(dev); 184 return retval; 185 186 err_free: 187 mutex_unlock(&acpi_dev->physical_node_lock); 188 kfree(physical_node); 189 goto err; 190 } 191 192 static int acpi_unbind_one(struct device *dev) 193 { 194 struct acpi_device_physical_node *entry; 195 struct acpi_device *acpi_dev; 196 acpi_status status; 197 struct list_head *node, *next; 198 199 if (!ACPI_HANDLE(dev)) 200 return 0; 201 202 status = acpi_bus_get_device(ACPI_HANDLE(dev), &acpi_dev); 203 if (ACPI_FAILURE(status)) 204 goto err; 205 206 mutex_lock(&acpi_dev->physical_node_lock); 207 list_for_each_safe(node, next, &acpi_dev->physical_node_list) { 208 char physical_node_name[sizeof(PHYSICAL_NODE_STRING) + 2]; 209 210 entry = list_entry(node, struct acpi_device_physical_node, 211 node); 212 if (entry->dev != dev) 213 continue; 214 215 list_del(node); 216 clear_bit(entry->node_id, acpi_dev->physical_node_id_bitmap); 217 218 acpi_dev->physical_node_count--; 219 220 if (!entry->node_id) 221 strcpy(physical_node_name, PHYSICAL_NODE_STRING); 222 else 223 sprintf(physical_node_name, 224 "physical_node%d", entry->node_id); 225 226 sysfs_remove_link(&acpi_dev->dev.kobj, physical_node_name); 227 sysfs_remove_link(&dev->kobj, "firmware_node"); 228 ACPI_HANDLE_SET(dev, NULL); 229 /* acpi_bind_one increase refcnt by one */ 230 put_device(dev); 231 kfree(entry); 232 } 233 mutex_unlock(&acpi_dev->physical_node_lock); 234 235 return 0; 236 237 err: 238 dev_err(dev, "Oops, 'acpi_handle' corrupt\n"); 239 return -EINVAL; 240 } 241 242 static int acpi_platform_notify(struct device *dev) 243 { 244 struct acpi_bus_type *type = acpi_get_bus_type(dev); 245 acpi_handle handle; 246 int ret; 247 248 ret = acpi_bind_one(dev, NULL); 249 if (ret && type) { 250 ret = type->find_device(dev, &handle); 251 if (ret) { 252 DBG("Unable to get handle for %s\n", dev_name(dev)); 253 goto out; 254 } 255 ret = acpi_bind_one(dev, handle); 256 if (ret) 257 goto out; 258 } 259 260 if (type && type->setup) 261 type->setup(dev); 262 263 out: 264 #if ACPI_GLUE_DEBUG 265 if (!ret) { 266 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 267 268 acpi_get_name(ACPI_HANDLE(dev), ACPI_FULL_PATHNAME, &buffer); 269 DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer); 270 kfree(buffer.pointer); 271 } else 272 DBG("Device %s -> No ACPI support\n", dev_name(dev)); 273 #endif 274 275 return ret; 276 } 277 278 static int acpi_platform_notify_remove(struct device *dev) 279 { 280 struct acpi_bus_type *type; 281 282 type = acpi_get_bus_type(dev); 283 if (type && type->cleanup) 284 type->cleanup(dev); 285 286 acpi_unbind_one(dev); 287 return 0; 288 } 289 290 int __init init_acpi_device_notify(void) 291 { 292 if (platform_notify || platform_notify_remove) { 293 printk(KERN_ERR PREFIX "Can't use platform_notify\n"); 294 return 0; 295 } 296 platform_notify = acpi_platform_notify; 297 platform_notify_remove = acpi_platform_notify_remove; 298 return 0; 299 } 300