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/init.h> 10 #include <linux/list.h> 11 #include <linux/device.h> 12 #include <linux/rwsem.h> 13 #include <linux/acpi.h> 14 15 #define ACPI_GLUE_DEBUG 0 16 #if ACPI_GLUE_DEBUG 17 #define DBG(x...) printk(PREFIX x) 18 #else 19 #define DBG(x...) do { } while(0) 20 #endif 21 static LIST_HEAD(bus_type_list); 22 static DECLARE_RWSEM(bus_type_sem); 23 24 int register_acpi_bus_type(struct acpi_bus_type *type) 25 { 26 if (acpi_disabled) 27 return -ENODEV; 28 if (type && type->bus && type->find_device) { 29 down_write(&bus_type_sem); 30 list_add_tail(&type->list, &bus_type_list); 31 up_write(&bus_type_sem); 32 printk(KERN_INFO PREFIX "bus type %s registered\n", 33 type->bus->name); 34 return 0; 35 } 36 return -ENODEV; 37 } 38 39 int unregister_acpi_bus_type(struct acpi_bus_type *type) 40 { 41 if (acpi_disabled) 42 return 0; 43 if (type) { 44 down_write(&bus_type_sem); 45 list_del_init(&type->list); 46 up_write(&bus_type_sem); 47 printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n", 48 type->bus->name); 49 return 0; 50 } 51 return -ENODEV; 52 } 53 54 static struct acpi_bus_type *acpi_get_bus_type(struct bus_type *type) 55 { 56 struct acpi_bus_type *tmp, *ret = NULL; 57 58 down_read(&bus_type_sem); 59 list_for_each_entry(tmp, &bus_type_list, list) { 60 if (tmp->bus == type) { 61 ret = tmp; 62 break; 63 } 64 } 65 up_read(&bus_type_sem); 66 return ret; 67 } 68 69 static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle) 70 { 71 struct acpi_bus_type *tmp; 72 int ret = -ENODEV; 73 74 down_read(&bus_type_sem); 75 list_for_each_entry(tmp, &bus_type_list, list) { 76 if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) { 77 ret = 0; 78 break; 79 } 80 } 81 up_read(&bus_type_sem); 82 return ret; 83 } 84 85 /* Get device's handler per its address under its parent */ 86 struct acpi_find_child { 87 acpi_handle handle; 88 acpi_integer address; 89 }; 90 91 static acpi_status 92 do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv) 93 { 94 acpi_status status; 95 struct acpi_device_info *info; 96 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 97 struct acpi_find_child *find = context; 98 99 status = acpi_get_object_info(handle, &buffer); 100 if (ACPI_SUCCESS(status)) { 101 info = buffer.pointer; 102 if (info->address == find->address) 103 find->handle = handle; 104 kfree(buffer.pointer); 105 } 106 return AE_OK; 107 } 108 109 acpi_handle acpi_get_child(acpi_handle parent, acpi_integer address) 110 { 111 struct acpi_find_child find = { NULL, address }; 112 113 if (!parent) 114 return NULL; 115 acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, 116 1, do_acpi_find_child, &find, NULL); 117 return find.handle; 118 } 119 120 EXPORT_SYMBOL(acpi_get_child); 121 122 /* Link ACPI devices with physical devices */ 123 static void acpi_glue_data_handler(acpi_handle handle, 124 u32 function, void *context) 125 { 126 /* we provide an empty handler */ 127 } 128 129 /* Note: a success call will increase reference count by one */ 130 struct device *acpi_get_physical_device(acpi_handle handle) 131 { 132 acpi_status status; 133 struct device *dev; 134 135 status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev); 136 if (ACPI_SUCCESS(status)) 137 return get_device(dev); 138 return NULL; 139 } 140 141 EXPORT_SYMBOL(acpi_get_physical_device); 142 143 static int acpi_bind_one(struct device *dev, acpi_handle handle) 144 { 145 acpi_status status; 146 147 if (dev->archdata.acpi_handle) { 148 printk(KERN_WARNING PREFIX 149 "Drivers changed 'acpi_handle' for %s\n", dev->bus_id); 150 return -EINVAL; 151 } 152 get_device(dev); 153 status = acpi_attach_data(handle, acpi_glue_data_handler, dev); 154 if (ACPI_FAILURE(status)) { 155 put_device(dev); 156 return -EINVAL; 157 } 158 dev->archdata.acpi_handle = handle; 159 160 return 0; 161 } 162 163 static int acpi_unbind_one(struct device *dev) 164 { 165 if (!dev->archdata.acpi_handle) 166 return 0; 167 if (dev == acpi_get_physical_device(dev->archdata.acpi_handle)) { 168 /* acpi_get_physical_device increase refcnt by one */ 169 put_device(dev); 170 acpi_detach_data(dev->archdata.acpi_handle, 171 acpi_glue_data_handler); 172 dev->archdata.acpi_handle = NULL; 173 /* acpi_bind_one increase refcnt by one */ 174 put_device(dev); 175 } else { 176 printk(KERN_ERR PREFIX 177 "Oops, 'acpi_handle' corrupt for %s\n", dev->bus_id); 178 } 179 return 0; 180 } 181 182 static int acpi_platform_notify(struct device *dev) 183 { 184 struct acpi_bus_type *type; 185 acpi_handle handle; 186 int ret = -EINVAL; 187 188 if (!dev->bus || !dev->parent) { 189 /* bridge devices genernally haven't bus or parent */ 190 ret = acpi_find_bridge_device(dev, &handle); 191 goto end; 192 } 193 type = acpi_get_bus_type(dev->bus); 194 if (!type) { 195 DBG("No ACPI bus support for %s\n", dev->bus_id); 196 ret = -EINVAL; 197 goto end; 198 } 199 if ((ret = type->find_device(dev, &handle)) != 0) 200 DBG("Can't get handler for %s\n", dev->bus_id); 201 end: 202 if (!ret) 203 acpi_bind_one(dev, handle); 204 205 #if ACPI_GLUE_DEBUG 206 if (!ret) { 207 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 208 209 acpi_get_name(dev->archdata.acpi_handle, 210 ACPI_FULL_PATHNAME, &buffer); 211 DBG("Device %s -> %s\n", dev->bus_id, (char *)buffer.pointer); 212 kfree(buffer.pointer); 213 } else 214 DBG("Device %s -> No ACPI support\n", dev->bus_id); 215 #endif 216 217 return ret; 218 } 219 220 static int acpi_platform_notify_remove(struct device *dev) 221 { 222 acpi_unbind_one(dev); 223 return 0; 224 } 225 226 static int __init init_acpi_device_notify(void) 227 { 228 if (acpi_disabled) 229 return 0; 230 if (platform_notify || platform_notify_remove) { 231 printk(KERN_ERR PREFIX "Can't use platform_notify\n"); 232 return 0; 233 } 234 platform_notify = acpi_platform_notify; 235 platform_notify_remove = acpi_platform_notify_remove; 236 return 0; 237 } 238 239 arch_initcall(init_acpi_device_notify); 240 241 242 #if defined(CONFIG_RTC_DRV_CMOS) || defined(CONFIG_RTC_DRV_CMOS_MODULE) 243 244 #ifdef CONFIG_PM 245 static u32 rtc_handler(void *context) 246 { 247 acpi_clear_event(ACPI_EVENT_RTC); 248 acpi_disable_event(ACPI_EVENT_RTC, 0); 249 return ACPI_INTERRUPT_HANDLED; 250 } 251 252 static inline void rtc_wake_setup(void) 253 { 254 acpi_install_fixed_event_handler(ACPI_EVENT_RTC, rtc_handler, NULL); 255 } 256 257 static void rtc_wake_on(struct device *dev) 258 { 259 acpi_clear_event(ACPI_EVENT_RTC); 260 acpi_enable_event(ACPI_EVENT_RTC, 0); 261 } 262 263 static void rtc_wake_off(struct device *dev) 264 { 265 acpi_disable_event(ACPI_EVENT_RTC, 0); 266 } 267 #else 268 #define rtc_wake_setup() do{}while(0) 269 #define rtc_wake_on NULL 270 #define rtc_wake_off NULL 271 #endif 272 273 /* Every ACPI platform has a mc146818 compatible "cmos rtc". Here we find 274 * its device node and pass extra config data. This helps its driver use 275 * capabilities that the now-obsolete mc146818 didn't have, and informs it 276 * that this board's RTC is wakeup-capable (per ACPI spec). 277 */ 278 #include <linux/mc146818rtc.h> 279 280 static struct cmos_rtc_board_info rtc_info; 281 282 283 /* PNP devices are registered in a subsys_initcall(); 284 * ACPI specifies the PNP IDs to use. 285 */ 286 #include <linux/pnp.h> 287 288 static int __init pnp_match(struct device *dev, void *data) 289 { 290 static const char *ids[] = { "PNP0b00", "PNP0b01", "PNP0b02", }; 291 struct pnp_dev *pnp = to_pnp_dev(dev); 292 int i; 293 294 for (i = 0; i < ARRAY_SIZE(ids); i++) { 295 if (compare_pnp_id(pnp->id, ids[i]) != 0) 296 return 1; 297 } 298 return 0; 299 } 300 301 static struct device *__init get_rtc_dev(void) 302 { 303 return bus_find_device(&pnp_bus_type, NULL, NULL, pnp_match); 304 } 305 306 static int __init acpi_rtc_init(void) 307 { 308 struct device *dev = get_rtc_dev(); 309 310 if (dev) { 311 rtc_wake_setup(); 312 rtc_info.wake_on = rtc_wake_on; 313 rtc_info.wake_off = rtc_wake_off; 314 315 /* workaround bug in some ACPI tables */ 316 if (acpi_gbl_FADT.month_alarm && !acpi_gbl_FADT.day_alarm) { 317 DBG("bogus FADT month_alarm\n"); 318 acpi_gbl_FADT.month_alarm = 0; 319 } 320 321 rtc_info.rtc_day_alarm = acpi_gbl_FADT.day_alarm; 322 rtc_info.rtc_mon_alarm = acpi_gbl_FADT.month_alarm; 323 rtc_info.rtc_century = acpi_gbl_FADT.century; 324 325 /* NOTE: S4_RTC_WAKE is NOT currently useful to Linux */ 326 if (acpi_gbl_FADT.flags & ACPI_FADT_S4_RTC_WAKE) 327 printk(PREFIX "RTC can wake from S4\n"); 328 329 330 dev->platform_data = &rtc_info; 331 332 /* RTC always wakes from S1/S2/S3, and often S4/STD */ 333 device_init_wakeup(dev, 1); 334 335 put_device(dev); 336 } else 337 DBG("RTC unavailable?\n"); 338 return 0; 339 } 340 /* do this between RTC subsys_initcall() and rtc_cmos driver_initcall() */ 341 fs_initcall(acpi_rtc_init); 342 343 #endif 344