[PATCH] sysfs: (rest) if show/store is missing return -EIO
[linux-2.6.git] / drivers / acpi / scan.c
1 /*
2  * scan.c - support for transforming the ACPI namespace into individual objects
3  */
4
5 #include <linux/module.h>
6 #include <linux/init.h>
7 #include <linux/acpi.h>
8
9 #include <acpi/acpi_drivers.h>
10 #include <acpi/acinterp.h>      /* for acpi_ex_eisa_id_to_string() */
11
12
13 #define _COMPONENT              ACPI_BUS_COMPONENT
14 ACPI_MODULE_NAME                ("scan")
15
16 #define STRUCT_TO_INT(s)        (*((int*)&s))
17
18 extern struct acpi_device               *acpi_root;
19
20
21 #define ACPI_BUS_CLASS                  "system_bus"
22 #define ACPI_BUS_HID                    "ACPI_BUS"
23 #define ACPI_BUS_DRIVER_NAME            "ACPI Bus Driver"
24 #define ACPI_BUS_DEVICE_NAME            "System Bus"
25
26 static LIST_HEAD(acpi_device_list);
27 DEFINE_SPINLOCK(acpi_device_lock);
28 LIST_HEAD(acpi_wakeup_device_list);
29
30 static int
31 acpi_bus_trim(struct acpi_device        *start,
32                 int rmdevice);
33
34 static void acpi_device_release(struct kobject * kobj)
35 {
36         struct acpi_device * dev = container_of(kobj,struct acpi_device,kobj);
37         if (dev->pnp.cid_list)
38                 kfree(dev->pnp.cid_list);
39         kfree(dev);
40 }
41
42 struct acpi_device_attribute {
43         struct attribute attr;
44         ssize_t (*show)(struct acpi_device *, char *);
45         ssize_t (*store)(struct acpi_device *, const char *, size_t);
46 };
47
48 typedef void acpi_device_sysfs_files(struct kobject *,
49                                 const struct attribute *);
50
51 static void setup_sys_fs_device_files(struct acpi_device *dev,
52                 acpi_device_sysfs_files *func);
53
54 #define create_sysfs_device_files(dev)  \
55         setup_sys_fs_device_files(dev, (acpi_device_sysfs_files *)&sysfs_create_file)
56 #define remove_sysfs_device_files(dev)  \
57         setup_sys_fs_device_files(dev, (acpi_device_sysfs_files *)&sysfs_remove_file)
58
59
60 #define to_acpi_device(n) container_of(n, struct acpi_device, kobj)
61 #define to_handle_attr(n) container_of(n, struct acpi_device_attribute, attr);
62
63 static ssize_t acpi_device_attr_show(struct kobject *kobj,
64                 struct attribute *attr, char *buf)
65 {
66         struct acpi_device *device = to_acpi_device(kobj);
67         struct acpi_device_attribute *attribute = to_handle_attr(attr);
68         return attribute->show ? attribute->show(device, buf) : -EIO;
69 }
70 static ssize_t acpi_device_attr_store(struct kobject *kobj,
71                 struct attribute *attr, const char *buf, size_t len)
72 {
73         struct acpi_device *device = to_acpi_device(kobj);
74         struct acpi_device_attribute *attribute = to_handle_attr(attr);
75         return attribute->store ? attribute->store(device, buf, len) : -EIO;
76 }
77
78 static struct sysfs_ops acpi_device_sysfs_ops = {
79         .show   = acpi_device_attr_show,
80         .store  = acpi_device_attr_store,
81 };
82
83 static struct kobj_type ktype_acpi_ns = {
84         .sysfs_ops      = &acpi_device_sysfs_ops,
85         .release        = acpi_device_release,
86 };
87
88 static int namespace_hotplug(struct kset *kset, struct kobject *kobj,
89                              char **envp, int num_envp, char *buffer,
90                              int buffer_size)
91 {
92         struct acpi_device *dev = to_acpi_device(kobj);
93         int i = 0;
94         int len = 0;
95
96         if (!dev->driver)
97                 return 0;
98
99         if (add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size, &len,
100                                 "PHYSDEVDRIVER=%s", dev->driver->name))
101                 return -ENOMEM;
102
103         envp[i] = NULL;
104
105         return 0;
106 }
107
108 static struct kset_hotplug_ops namespace_hotplug_ops = {
109         .hotplug = &namespace_hotplug,
110 };
111
112 static struct kset acpi_namespace_kset = {
113         .kobj           = { 
114                 .name = "namespace",
115         },
116         .subsys = &acpi_subsys,
117         .ktype  = &ktype_acpi_ns,
118         .hotplug_ops = &namespace_hotplug_ops,
119 };
120
121
122 static void acpi_device_register(struct acpi_device * device, struct acpi_device * parent)
123 {
124         /*
125          * Linkage
126          * -------
127          * Link this device to its parent and siblings.
128          */
129         INIT_LIST_HEAD(&device->children);
130         INIT_LIST_HEAD(&device->node);
131         INIT_LIST_HEAD(&device->g_list);
132         INIT_LIST_HEAD(&device->wakeup_list);
133
134         spin_lock(&acpi_device_lock);
135         if (device->parent) {
136                 list_add_tail(&device->node, &device->parent->children);
137                 list_add_tail(&device->g_list,&device->parent->g_list);
138         } else
139                 list_add_tail(&device->g_list,&acpi_device_list);
140         if (device->wakeup.flags.valid)
141                 list_add_tail(&device->wakeup_list,&acpi_wakeup_device_list);
142         spin_unlock(&acpi_device_lock);
143
144         strlcpy(device->kobj.name,device->pnp.bus_id,KOBJ_NAME_LEN);
145         if (parent)
146                 device->kobj.parent = &parent->kobj;
147         device->kobj.ktype = &ktype_acpi_ns;
148         device->kobj.kset = &acpi_namespace_kset;
149         kobject_register(&device->kobj);
150         create_sysfs_device_files(device);
151 }
152
153 static int
154 acpi_device_unregister (
155         struct acpi_device      *device, 
156         int                     type)
157 {
158         spin_lock(&acpi_device_lock);
159         if (device->parent) {
160                 list_del(&device->node);
161                 list_del(&device->g_list);
162         } else
163                 list_del(&device->g_list);
164
165         list_del(&device->wakeup_list);
166
167         spin_unlock(&acpi_device_lock);
168
169         acpi_detach_data(device->handle, acpi_bus_data_handler);
170         remove_sysfs_device_files(device);
171         kobject_unregister(&device->kobj);
172         return 0;
173 }
174
175 void
176 acpi_bus_data_handler (
177         acpi_handle             handle,
178         u32                     function,
179         void                    *context)
180 {
181         ACPI_FUNCTION_TRACE("acpi_bus_data_handler");
182
183         /* TBD */
184
185         return_VOID;
186 }
187
188 static int
189 acpi_bus_get_power_flags (
190         struct acpi_device      *device)
191 {
192         acpi_status             status = 0;
193         acpi_handle             handle = NULL;
194         u32                     i = 0;
195
196         ACPI_FUNCTION_TRACE("acpi_bus_get_power_flags");
197
198         /*
199          * Power Management Flags
200          */
201         status = acpi_get_handle(device->handle, "_PSC", &handle);
202         if (ACPI_SUCCESS(status))
203                 device->power.flags.explicit_get = 1;
204         status = acpi_get_handle(device->handle, "_IRC", &handle);
205         if (ACPI_SUCCESS(status))
206                 device->power.flags.inrush_current = 1;
207
208         /*
209          * Enumerate supported power management states
210          */
211         for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3; i++) {
212                 struct acpi_device_power_state *ps = &device->power.states[i];
213                 char            object_name[5] = {'_','P','R','0'+i,'\0'};
214
215                 /* Evaluate "_PRx" to se if power resources are referenced */
216                 acpi_evaluate_reference(device->handle, object_name, NULL,
217                         &ps->resources);
218                 if (ps->resources.count) {
219                         device->power.flags.power_resources = 1;
220                         ps->flags.valid = 1;
221                 }
222
223                 /* Evaluate "_PSx" to see if we can do explicit sets */
224                 object_name[2] = 'S';
225                 status = acpi_get_handle(device->handle, object_name, &handle);
226                 if (ACPI_SUCCESS(status)) {
227                         ps->flags.explicit_set = 1;
228                         ps->flags.valid = 1;
229                 }
230
231                 /* State is valid if we have some power control */
232                 if (ps->resources.count || ps->flags.explicit_set)
233                         ps->flags.valid = 1;
234
235                 ps->power = -1;         /* Unknown - driver assigned */
236                 ps->latency = -1;       /* Unknown - driver assigned */
237         }
238
239         /* Set defaults for D0 and D3 states (always valid) */
240         device->power.states[ACPI_STATE_D0].flags.valid = 1;
241         device->power.states[ACPI_STATE_D0].power = 100;
242         device->power.states[ACPI_STATE_D3].flags.valid = 1;
243         device->power.states[ACPI_STATE_D3].power = 0;
244
245         /* TBD: System wake support and resource requirements. */
246
247         device->power.state = ACPI_STATE_UNKNOWN;
248
249         return_VALUE(0);
250 }
251
252 int
253 acpi_match_ids (
254         struct acpi_device      *device,
255         char                    *ids)
256 {
257         int error = 0;
258         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
259
260         if (device->flags.hardware_id)
261                 if (strstr(ids, device->pnp.hardware_id))
262                         goto Done;
263
264         if (device->flags.compatible_ids) {
265                 struct acpi_compatible_id_list *cid_list = device->pnp.cid_list;
266                 int i;
267
268                 /* compare multiple _CID entries against driver ids */
269                 for (i = 0; i < cid_list->count; i++)
270                 {
271                         if (strstr(ids, cid_list->id[i].value))
272                                 goto Done;
273                 }
274         }
275         error = -ENOENT;
276
277  Done:
278         if (buffer.pointer)
279                 acpi_os_free(buffer.pointer);
280         return error;
281 }
282
283 static acpi_status
284 acpi_bus_extract_wakeup_device_power_package (
285         struct acpi_device      *device,
286         union acpi_object       *package)
287 {
288         int      i = 0;
289         union acpi_object       *element = NULL;
290
291         if (!device || !package || (package->package.count < 2))
292                 return AE_BAD_PARAMETER;
293
294         element = &(package->package.elements[0]);
295         if (!element)
296                 return AE_BAD_PARAMETER;
297         if (element->type == ACPI_TYPE_PACKAGE) {
298                 if ((element->package.count < 2) ||
299                         (element->package.elements[0].type != ACPI_TYPE_LOCAL_REFERENCE) ||
300                         (element->package.elements[1].type != ACPI_TYPE_INTEGER))
301                         return AE_BAD_DATA;
302                 device->wakeup.gpe_device = element->package.elements[0].reference.handle;
303                 device->wakeup.gpe_number = (u32)element->package.elements[1].integer.value;
304         }else if (element->type == ACPI_TYPE_INTEGER) {
305                 device->wakeup.gpe_number = element->integer.value;
306         }else
307                 return AE_BAD_DATA;
308
309         element = &(package->package.elements[1]);
310         if (element->type != ACPI_TYPE_INTEGER) {
311                 return AE_BAD_DATA;
312         }
313         device->wakeup.sleep_state = element->integer.value;
314
315         if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
316                 return AE_NO_MEMORY;
317         }
318         device->wakeup.resources.count = package->package.count - 2;
319         for (i=0; i < device->wakeup.resources.count; i++) {
320                 element = &(package->package.elements[i + 2]);
321                 if (element->type != ACPI_TYPE_ANY ) {
322                         return AE_BAD_DATA;
323                 }
324
325                 device->wakeup.resources.handles[i] = element->reference.handle;
326         }
327
328         return AE_OK;
329 }
330
331 static int
332 acpi_bus_get_wakeup_device_flags (
333         struct acpi_device      *device)
334 {
335         acpi_status     status = 0;
336         struct acpi_buffer      buffer = {ACPI_ALLOCATE_BUFFER, NULL};
337         union acpi_object       *package = NULL;
338
339         ACPI_FUNCTION_TRACE("acpi_bus_get_wakeup_flags");
340
341         /* _PRW */
342         status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer);
343         if (ACPI_FAILURE(status)) {
344                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PRW\n"));
345                 goto end;
346         }
347
348         package = (union acpi_object *) buffer.pointer;
349         status = acpi_bus_extract_wakeup_device_power_package(device, package);
350         if (ACPI_FAILURE(status)) {
351                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error extracting _PRW package\n"));
352                 goto end;
353         }
354
355         acpi_os_free(buffer.pointer);
356
357         device->wakeup.flags.valid = 1;
358         /* Power button, Lid switch always enable wakeup*/
359         if (!acpi_match_ids(device, "PNP0C0D,PNP0C0C,PNP0C0E"))
360                 device->wakeup.flags.run_wake = 1;
361
362 end:
363         if (ACPI_FAILURE(status))
364                 device->flags.wake_capable = 0;
365         return_VALUE(0);
366 }
367
368 /* --------------------------------------------------------------------------
369                 ACPI hotplug sysfs device file support
370    -------------------------------------------------------------------------- */
371 static ssize_t acpi_eject_store(struct acpi_device *device, 
372                 const char *buf, size_t count);
373
374 #define ACPI_DEVICE_ATTR(_name,_mode,_show,_store) \
375 static struct acpi_device_attribute acpi_device_attr_##_name = \
376                 __ATTR(_name, _mode, _show, _store)
377
378 ACPI_DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
379
380 /**
381  * setup_sys_fs_device_files - sets up the device files under device namespace
382  * @dev:        acpi_device object
383  * @func:       function pointer to create or destroy the device file
384  */
385 static void
386 setup_sys_fs_device_files (
387         struct acpi_device *dev,
388         acpi_device_sysfs_files *func)
389 {
390         acpi_status             status;
391         acpi_handle             temp = NULL;
392
393         /*
394          * If device has _EJ0, 'eject' file is created that is used to trigger
395          * hot-removal function from userland.
396          */
397         status = acpi_get_handle(dev->handle, "_EJ0", &temp);
398         if (ACPI_SUCCESS(status))
399                 (*(func))(&dev->kobj,&acpi_device_attr_eject.attr);
400 }
401
402 static int
403 acpi_eject_operation(acpi_handle handle, int lockable)
404 {
405         struct acpi_object_list arg_list;
406         union acpi_object arg;
407         acpi_status status = AE_OK;
408
409         /*
410          * TBD: evaluate _PS3?
411          */
412
413         if (lockable) {
414                 arg_list.count = 1;
415                 arg_list.pointer = &arg;
416                 arg.type = ACPI_TYPE_INTEGER;
417                 arg.integer.value = 0;
418                 acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
419         }
420
421         arg_list.count = 1;
422         arg_list.pointer = &arg;
423         arg.type = ACPI_TYPE_INTEGER;
424         arg.integer.value = 1;
425
426         /*
427          * TBD: _EJD support.
428          */
429
430         status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
431         if (ACPI_FAILURE(status)) {
432                 return(-ENODEV);
433         }
434
435         return(0);
436 }
437
438
439 static ssize_t
440 acpi_eject_store(struct acpi_device *device, const char *buf, size_t count)
441 {
442         int     result;
443         int     ret = count;
444         int     islockable;
445         acpi_status     status;
446         acpi_handle     handle;
447         acpi_object_type        type = 0;
448
449         if ((!count) || (buf[0] != '1')) {
450                 return -EINVAL;
451         }
452
453 #ifndef FORCE_EJECT
454         if (device->driver == NULL) {
455                 ret = -ENODEV;
456                 goto err;
457         }
458 #endif
459         status = acpi_get_type(device->handle, &type);
460         if (ACPI_FAILURE(status) || (!device->flags.ejectable) ) {
461                 ret = -ENODEV;
462                 goto err;
463         }
464
465         islockable = device->flags.lockable;
466         handle = device->handle;
467
468         if (type == ACPI_TYPE_PROCESSOR)
469                 result = acpi_bus_trim(device, 0);
470         else
471                 result = acpi_bus_trim(device, 1);
472
473         if (!result)
474                 result = acpi_eject_operation(handle, islockable);
475
476         if (result) {
477                 ret = -EBUSY;
478         }
479 err:
480         return ret;
481 }
482
483
484 /* --------------------------------------------------------------------------
485                               Performance Management
486    -------------------------------------------------------------------------- */
487
488 static int
489 acpi_bus_get_perf_flags (
490         struct acpi_device      *device)
491 {
492         device->performance.state = ACPI_STATE_UNKNOWN;
493         return 0;
494 }
495
496 /* --------------------------------------------------------------------------
497                                  Driver Management
498    -------------------------------------------------------------------------- */
499
500 static LIST_HEAD(acpi_bus_drivers);
501 static DECLARE_MUTEX(acpi_bus_drivers_lock);
502
503
504 /**
505  * acpi_bus_match 
506  * --------------
507  * Checks the device's hardware (_HID) or compatible (_CID) ids to see if it
508  * matches the specified driver's criteria.
509  */
510 static int
511 acpi_bus_match (
512         struct acpi_device      *device,
513         struct acpi_driver      *driver)
514 {
515         if (driver && driver->ops.match)
516                 return driver->ops.match(device, driver);
517         return acpi_match_ids(device, driver->ids);
518 }
519
520
521 /**
522  * acpi_bus_driver_init 
523  * --------------------
524  * Used to initialize a device via its device driver.  Called whenever a 
525  * driver is bound to a device.  Invokes the driver's add() and start() ops.
526  */
527 static int
528 acpi_bus_driver_init (
529         struct acpi_device      *device, 
530         struct acpi_driver      *driver)
531 {
532         int                     result = 0;
533
534         ACPI_FUNCTION_TRACE("acpi_bus_driver_init");
535
536         if (!device || !driver)
537                 return_VALUE(-EINVAL);
538
539         if (!driver->ops.add)
540                 return_VALUE(-ENOSYS);
541
542         result = driver->ops.add(device);
543         if (result) {
544                 device->driver = NULL;
545                 acpi_driver_data(device) = NULL;
546                 return_VALUE(result);
547         }
548
549         device->driver = driver;
550
551         /*
552          * TBD - Configuration Management: Assign resources to device based
553          * upon possible configuration and currently allocated resources.
554          */
555
556         if (driver->ops.start) {
557                 result = driver->ops.start(device);
558                 if (result && driver->ops.remove)
559                         driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
560                 return_VALUE(result);
561         }
562
563         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Driver successfully bound to device\n"));
564
565         if (driver->ops.scan) {
566                 driver->ops.scan(device);
567         }
568
569         return_VALUE(0);
570 }
571
572 static int acpi_driver_attach(struct acpi_driver * drv)
573 {
574         struct list_head * node, * next;
575         int count = 0;
576
577         ACPI_FUNCTION_TRACE("acpi_driver_attach");
578
579         spin_lock(&acpi_device_lock);
580         list_for_each_safe(node, next, &acpi_device_list) {
581                 struct acpi_device * dev = container_of(node, struct acpi_device, g_list);
582
583                 if (dev->driver || !dev->status.present)
584                         continue;
585                 spin_unlock(&acpi_device_lock);
586
587                 if (!acpi_bus_match(dev, drv)) {
588                         if (!acpi_bus_driver_init(dev, drv)) {
589                                 atomic_inc(&drv->references);
590                                 count++;
591                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found driver [%s] for device [%s]\n",
592                                                   drv->name, dev->pnp.bus_id));
593                         }
594                 }
595                 spin_lock(&acpi_device_lock);
596         }
597         spin_unlock(&acpi_device_lock);
598         return_VALUE(count);
599 }
600
601 static int acpi_driver_detach(struct acpi_driver * drv)
602 {
603         struct list_head * node, * next;
604
605         ACPI_FUNCTION_TRACE("acpi_driver_detach");
606
607         spin_lock(&acpi_device_lock);
608         list_for_each_safe(node,next,&acpi_device_list) {
609                 struct acpi_device * dev = container_of(node,struct acpi_device,g_list);
610
611                 if (dev->driver == drv) {
612                         spin_unlock(&acpi_device_lock);
613                         if (drv->ops.remove)
614                                 drv->ops.remove(dev,ACPI_BUS_REMOVAL_NORMAL);
615                         spin_lock(&acpi_device_lock);
616                         dev->driver = NULL;
617                         dev->driver_data = NULL;
618                         atomic_dec(&drv->references);
619                 }
620         }
621         spin_unlock(&acpi_device_lock);
622         return_VALUE(0);
623 }
624
625 /**
626  * acpi_bus_register_driver 
627  * ------------------------ 
628  * Registers a driver with the ACPI bus.  Searches the namespace for all
629  * devices that match the driver's criteria and binds.  Returns the
630  * number of devices that were claimed by the driver, or a negative
631  * error status for failure.
632  */
633 int
634 acpi_bus_register_driver (
635         struct acpi_driver      *driver)
636 {
637         int count;
638
639         ACPI_FUNCTION_TRACE("acpi_bus_register_driver");
640
641         if (acpi_disabled)
642                 return_VALUE(-ENODEV);
643
644         if (!driver)
645                 return_VALUE(-EINVAL);
646
647         spin_lock(&acpi_device_lock);
648         list_add_tail(&driver->node, &acpi_bus_drivers);
649         spin_unlock(&acpi_device_lock);
650         count = acpi_driver_attach(driver);
651
652         return_VALUE(count);
653 }
654 EXPORT_SYMBOL(acpi_bus_register_driver);
655
656
657 /**
658  * acpi_bus_unregister_driver 
659  * --------------------------
660  * Unregisters a driver with the ACPI bus.  Searches the namespace for all
661  * devices that match the driver's criteria and unbinds.
662  */
663 int
664 acpi_bus_unregister_driver (
665         struct acpi_driver      *driver)
666 {
667         int error = 0;
668
669         ACPI_FUNCTION_TRACE("acpi_bus_unregister_driver");
670
671         if (driver) {
672                 acpi_driver_detach(driver);
673
674                 if (!atomic_read(&driver->references)) {
675                         spin_lock(&acpi_device_lock);
676                         list_del_init(&driver->node);
677                         spin_unlock(&acpi_device_lock);
678                 } 
679         } else 
680                 error = -EINVAL;
681         return_VALUE(error);
682 }
683 EXPORT_SYMBOL(acpi_bus_unregister_driver);
684
685 /**
686  * acpi_bus_find_driver 
687  * --------------------
688  * Parses the list of registered drivers looking for a driver applicable for
689  * the specified device.
690  */
691 static int
692 acpi_bus_find_driver (
693         struct acpi_device      *device)
694 {
695         int                     result = 0;
696         struct list_head        * node, *next;
697
698         ACPI_FUNCTION_TRACE("acpi_bus_find_driver");
699
700         spin_lock(&acpi_device_lock);
701         list_for_each_safe(node,next,&acpi_bus_drivers) {
702                 struct acpi_driver * driver = container_of(node,struct acpi_driver,node);
703
704                 atomic_inc(&driver->references);
705                 spin_unlock(&acpi_device_lock);
706                 if (!acpi_bus_match(device, driver)) {
707                         result = acpi_bus_driver_init(device, driver);
708                         if (!result)
709                                 goto Done;
710                 }
711                 atomic_dec(&driver->references);
712                 spin_lock(&acpi_device_lock);
713         }
714         spin_unlock(&acpi_device_lock);
715
716  Done:
717         return_VALUE(result);
718 }
719
720
721 /* --------------------------------------------------------------------------
722                                  Device Enumeration
723    -------------------------------------------------------------------------- */
724
725 static int 
726 acpi_bus_get_flags (
727         struct acpi_device      *device)
728 {
729         acpi_status             status = AE_OK;
730         acpi_handle             temp = NULL;
731
732         ACPI_FUNCTION_TRACE("acpi_bus_get_flags");
733
734         /* Presence of _STA indicates 'dynamic_status' */
735         status = acpi_get_handle(device->handle, "_STA", &temp);
736         if (ACPI_SUCCESS(status))
737                 device->flags.dynamic_status = 1;
738
739         /* Presence of _CID indicates 'compatible_ids' */
740         status = acpi_get_handle(device->handle, "_CID", &temp);
741         if (ACPI_SUCCESS(status))
742                 device->flags.compatible_ids = 1;
743
744         /* Presence of _RMV indicates 'removable' */
745         status = acpi_get_handle(device->handle, "_RMV", &temp);
746         if (ACPI_SUCCESS(status))
747                 device->flags.removable = 1;
748
749         /* Presence of _EJD|_EJ0 indicates 'ejectable' */
750         status = acpi_get_handle(device->handle, "_EJD", &temp);
751         if (ACPI_SUCCESS(status))
752                 device->flags.ejectable = 1;
753         else {
754                 status = acpi_get_handle(device->handle, "_EJ0", &temp);
755                 if (ACPI_SUCCESS(status))
756                         device->flags.ejectable = 1;
757         }
758
759         /* Presence of _LCK indicates 'lockable' */
760         status = acpi_get_handle(device->handle, "_LCK", &temp);
761         if (ACPI_SUCCESS(status))
762                 device->flags.lockable = 1;
763
764         /* Presence of _PS0|_PR0 indicates 'power manageable' */
765         status = acpi_get_handle(device->handle, "_PS0", &temp);
766         if (ACPI_FAILURE(status))
767                 status = acpi_get_handle(device->handle, "_PR0", &temp);
768         if (ACPI_SUCCESS(status))
769                 device->flags.power_manageable = 1;
770
771         /* Presence of _PRW indicates wake capable */
772         status = acpi_get_handle(device->handle, "_PRW", &temp);
773         if (ACPI_SUCCESS(status))
774                 device->flags.wake_capable = 1;
775
776         /* TBD: Peformance management */
777
778         return_VALUE(0);
779 }
780
781 static void acpi_device_get_busid(struct acpi_device * device, acpi_handle handle, int type)
782 {
783         char                    bus_id[5] = {'?',0};
784         struct acpi_buffer      buffer = {sizeof(bus_id), bus_id};
785         int                     i = 0;
786
787         /*
788          * Bus ID
789          * ------
790          * The device's Bus ID is simply the object name.
791          * TBD: Shouldn't this value be unique (within the ACPI namespace)?
792          */
793         switch (type) {
794         case ACPI_BUS_TYPE_SYSTEM:
795                 strcpy(device->pnp.bus_id, "ACPI");
796                 break;
797         case ACPI_BUS_TYPE_POWER_BUTTON:
798                 strcpy(device->pnp.bus_id, "PWRF");
799                 break;
800         case ACPI_BUS_TYPE_SLEEP_BUTTON:
801                 strcpy(device->pnp.bus_id, "SLPF");
802                 break;
803         default:
804                 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
805                 /* Clean up trailing underscores (if any) */
806                 for (i = 3; i > 1; i--) {
807                         if (bus_id[i] == '_')
808                                 bus_id[i] = '\0';
809                         else
810                                 break;
811                 }
812                 strcpy(device->pnp.bus_id, bus_id);
813                 break;
814         }
815 }
816
817 static void acpi_device_set_id(struct acpi_device * device, struct acpi_device * parent,
818                                acpi_handle handle, int type)
819 {
820         struct acpi_device_info *info;
821         struct acpi_buffer      buffer = {ACPI_ALLOCATE_BUFFER, NULL};
822         char                    *hid = NULL;
823         char                    *uid = NULL;
824         struct acpi_compatible_id_list *cid_list = NULL;
825         acpi_status             status;
826
827         switch (type) {
828         case ACPI_BUS_TYPE_DEVICE:
829                 status = acpi_get_object_info(handle, &buffer);
830                 if (ACPI_FAILURE(status)) {
831                         printk("%s: Error reading device info\n",__FUNCTION__);
832                         return;
833                 }
834
835                 info = buffer.pointer;
836                 if (info->valid & ACPI_VALID_HID)
837                         hid = info->hardware_id.value;
838                 if (info->valid & ACPI_VALID_UID)
839                         uid = info->unique_id.value;
840                 if (info->valid & ACPI_VALID_CID)
841                         cid_list = &info->compatibility_id;
842                 if (info->valid & ACPI_VALID_ADR) {
843                         device->pnp.bus_address = info->address;
844                         device->flags.bus_address = 1;
845                 }
846                 break;
847         case ACPI_BUS_TYPE_POWER:
848                 hid = ACPI_POWER_HID;
849                 break;
850         case ACPI_BUS_TYPE_PROCESSOR:
851                 hid = ACPI_PROCESSOR_HID;
852                 break;
853         case ACPI_BUS_TYPE_SYSTEM:
854                 hid = ACPI_SYSTEM_HID;
855                 break;
856         case ACPI_BUS_TYPE_THERMAL:
857                 hid = ACPI_THERMAL_HID;
858                 break;
859         case ACPI_BUS_TYPE_POWER_BUTTON:
860                 hid = ACPI_BUTTON_HID_POWERF;
861                 break;
862         case ACPI_BUS_TYPE_SLEEP_BUTTON:
863                 hid = ACPI_BUTTON_HID_SLEEPF;
864                 break;
865         }
866
867         /* 
868          * \_SB
869          * ----
870          * Fix for the system root bus device -- the only root-level device.
871          */
872         if ((parent == ACPI_ROOT_OBJECT) && (type == ACPI_BUS_TYPE_DEVICE)) {
873                 hid = ACPI_BUS_HID;
874                 strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
875                 strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
876         }
877
878         if (hid) {
879                 strcpy(device->pnp.hardware_id, hid);
880                 device->flags.hardware_id = 1;
881         }
882         if (uid) {
883                 strcpy(device->pnp.unique_id, uid);
884                 device->flags.unique_id = 1;
885         }
886         if (cid_list) {
887                 device->pnp.cid_list = kmalloc(cid_list->size, GFP_KERNEL);
888                 if (device->pnp.cid_list)
889                         memcpy(device->pnp.cid_list, cid_list, cid_list->size);
890                 else
891                         printk(KERN_ERR "Memory allocation error\n");
892         }
893
894         acpi_os_free(buffer.pointer);
895 }
896
897 static int acpi_device_set_context(struct acpi_device * device, int type)
898 {
899         acpi_status status = AE_OK;
900         int result = 0;
901         /*
902          * Context
903          * -------
904          * Attach this 'struct acpi_device' to the ACPI object.  This makes
905          * resolutions from handle->device very efficient.  Note that we need
906          * to be careful with fixed-feature devices as they all attach to the
907          * root object.
908          */
909         if (type != ACPI_BUS_TYPE_POWER_BUTTON && 
910             type != ACPI_BUS_TYPE_SLEEP_BUTTON) {
911                 status = acpi_attach_data(device->handle,
912                         acpi_bus_data_handler, device);
913
914                 if (ACPI_FAILURE(status)) {
915                         printk("Error attaching device data\n");
916                         result = -ENODEV;
917                 }
918         }
919         return result;
920 }
921
922 static void acpi_device_get_debug_info(struct acpi_device * device, acpi_handle handle, int type)
923 {
924 #ifdef CONFIG_ACPI_DEBUG_OUTPUT
925         char            *type_string = NULL;
926         char            name[80] = {'?','\0'};
927         struct acpi_buffer      buffer = {sizeof(name), name};
928
929         switch (type) {
930         case ACPI_BUS_TYPE_DEVICE:
931                 type_string = "Device";
932                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
933                 break;
934         case ACPI_BUS_TYPE_POWER:
935                 type_string = "Power Resource";
936                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
937                 break;
938         case ACPI_BUS_TYPE_PROCESSOR:
939                 type_string = "Processor";
940                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
941                 break;
942         case ACPI_BUS_TYPE_SYSTEM:
943                 type_string = "System";
944                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
945                 break;
946         case ACPI_BUS_TYPE_THERMAL:
947                 type_string = "Thermal Zone";
948                 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
949                 break;
950         case ACPI_BUS_TYPE_POWER_BUTTON:
951                 type_string = "Power Button";
952                 sprintf(name, "PWRB");
953                 break;
954         case ACPI_BUS_TYPE_SLEEP_BUTTON:
955                 type_string = "Sleep Button";
956                 sprintf(name, "SLPB");
957                 break;
958         }
959
960         printk(KERN_DEBUG "Found %s %s [%p]\n", type_string, name, handle);
961 #endif /*CONFIG_ACPI_DEBUG_OUTPUT*/
962 }
963
964
965 static int
966 acpi_bus_remove (
967         struct acpi_device *dev,
968         int rmdevice)
969 {
970         int                     result = 0;
971         struct acpi_driver      *driver;
972         
973         ACPI_FUNCTION_TRACE("acpi_bus_remove");
974
975         if (!dev)
976                 return_VALUE(-EINVAL);
977
978         driver = dev->driver;
979
980         if ((driver) && (driver->ops.remove)) {
981
982                 if (driver->ops.stop) {
983                         result = driver->ops.stop(dev, ACPI_BUS_REMOVAL_EJECT);
984                         if (result)
985                                 return_VALUE(result);
986                 }
987
988                 result = dev->driver->ops.remove(dev, ACPI_BUS_REMOVAL_EJECT);
989                 if (result) {
990                         return_VALUE(result);
991                 }
992
993                 atomic_dec(&dev->driver->references);
994                 dev->driver = NULL;
995                 acpi_driver_data(dev) = NULL;
996         }
997
998         if (!rmdevice)
999                 return_VALUE(0);
1000
1001         if (dev->flags.bus_address) {
1002                 if ((dev->parent) && (dev->parent->ops.unbind))
1003                         dev->parent->ops.unbind(dev);
1004         }
1005         
1006         acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
1007
1008         return_VALUE(0);
1009 }
1010
1011
1012 int
1013 acpi_bus_add (
1014         struct acpi_device      **child,
1015         struct acpi_device      *parent,
1016         acpi_handle             handle,
1017         int                     type)
1018 {
1019         int                     result = 0;
1020         struct acpi_device      *device = NULL;
1021
1022         ACPI_FUNCTION_TRACE("acpi_bus_add");
1023
1024         if (!child)
1025                 return_VALUE(-EINVAL);
1026
1027         device = kmalloc(sizeof(struct acpi_device), GFP_KERNEL);
1028         if (!device) {
1029                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Memory allocation error\n"));
1030                 return_VALUE(-ENOMEM);
1031         }
1032         memset(device, 0, sizeof(struct acpi_device));
1033
1034         device->handle = handle;
1035         device->parent = parent;
1036
1037         acpi_device_get_busid(device,handle,type);
1038
1039         /*
1040          * Flags
1041          * -----
1042          * Get prior to calling acpi_bus_get_status() so we know whether
1043          * or not _STA is present.  Note that we only look for object
1044          * handles -- cannot evaluate objects until we know the device is
1045          * present and properly initialized.
1046          */
1047         result = acpi_bus_get_flags(device);
1048         if (result)
1049                 goto end;
1050
1051         /*
1052          * Status
1053          * ------
1054          * See if the device is present.  We always assume that non-Device()
1055          * objects (e.g. thermal zones, power resources, processors, etc.) are
1056          * present, functioning, etc. (at least when parent object is present).
1057          * Note that _STA has a different meaning for some objects (e.g.
1058          * power resources) so we need to be careful how we use it.
1059          */
1060         switch (type) {
1061         case ACPI_BUS_TYPE_DEVICE:
1062                 result = acpi_bus_get_status(device);
1063                 if (ACPI_FAILURE(result) || !device->status.present) {
1064                         result = -ENOENT;
1065                         goto end;
1066                 }
1067                 break;
1068         default:
1069                 STRUCT_TO_INT(device->status) = 0x0F;
1070                 break;
1071         }
1072
1073         /*
1074          * Initialize Device
1075          * -----------------
1076          * TBD: Synch with Core's enumeration/initialization process.
1077          */
1078
1079         /*
1080          * Hardware ID, Unique ID, & Bus Address
1081          * -------------------------------------
1082          */
1083         acpi_device_set_id(device,parent,handle,type);
1084
1085         /*
1086          * Power Management
1087          * ----------------
1088          */
1089         if (device->flags.power_manageable) {
1090                 result = acpi_bus_get_power_flags(device);
1091                 if (result)
1092                         goto end;
1093         }
1094
1095         /*
1096          * Wakeup device management
1097          *-----------------------
1098          */
1099         if (device->flags.wake_capable) {
1100                 result = acpi_bus_get_wakeup_device_flags(device);
1101                 if (result)
1102                         goto end;
1103         }
1104
1105         /*
1106          * Performance Management
1107          * ----------------------
1108          */
1109         if (device->flags.performance_manageable) {
1110                 result = acpi_bus_get_perf_flags(device);
1111                 if (result)
1112                         goto end;
1113         }
1114
1115         if ((result = acpi_device_set_context(device,type)))
1116                 goto end;
1117
1118         acpi_device_get_debug_info(device,handle,type);
1119
1120         acpi_device_register(device,parent);
1121
1122         /*
1123          * Bind _ADR-Based Devices
1124          * -----------------------
1125          * If there's a a bus address (_ADR) then we utilize the parent's 
1126          * 'bind' function (if exists) to bind the ACPI- and natively-
1127          * enumerated device representations.
1128          */
1129         if (device->flags.bus_address) {
1130                 if (device->parent && device->parent->ops.bind)
1131                         device->parent->ops.bind(device);
1132         }
1133
1134         /*
1135          * Locate & Attach Driver
1136          * ----------------------
1137          * If there's a hardware id (_HID) or compatible ids (_CID) we check
1138          * to see if there's a driver installed for this kind of device.  Note
1139          * that drivers can install before or after a device is enumerated.
1140          *
1141          * TBD: Assumes LDM provides driver hot-plug capability.
1142          */
1143         acpi_bus_find_driver(device);
1144
1145 end:
1146         if (!result)
1147                 *child = device;
1148         else {
1149                 if (device->pnp.cid_list)
1150                         kfree(device->pnp.cid_list);
1151                 kfree(device);
1152         }
1153
1154         return_VALUE(result);
1155 }
1156 EXPORT_SYMBOL(acpi_bus_add);
1157
1158
1159 int acpi_bus_scan (struct acpi_device   *start)
1160 {
1161         acpi_status             status = AE_OK;
1162         struct acpi_device      *parent = NULL;
1163         struct acpi_device      *child = NULL;
1164         acpi_handle             phandle = NULL;
1165         acpi_handle             chandle = NULL;
1166         acpi_object_type        type = 0;
1167         u32                     level = 1;
1168
1169         ACPI_FUNCTION_TRACE("acpi_bus_scan");
1170
1171         if (!start)
1172                 return_VALUE(-EINVAL);
1173
1174         parent = start;
1175         phandle = start->handle;
1176         
1177         /*
1178          * Parse through the ACPI namespace, identify all 'devices', and
1179          * create a new 'struct acpi_device' for each.
1180          */
1181         while ((level > 0) && parent) {
1182
1183                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1184                         chandle, &chandle);
1185
1186                 /*
1187                  * If this scope is exhausted then move our way back up.
1188                  */
1189                 if (ACPI_FAILURE(status)) {
1190                         level--;
1191                         chandle = phandle;
1192                         acpi_get_parent(phandle, &phandle);
1193                         if (parent->parent)
1194                                 parent = parent->parent;
1195                         continue;
1196                 }
1197
1198                 status = acpi_get_type(chandle, &type);
1199                 if (ACPI_FAILURE(status))
1200                         continue;
1201
1202                 /*
1203                  * If this is a scope object then parse it (depth-first).
1204                  */
1205                 if (type == ACPI_TYPE_LOCAL_SCOPE) {
1206                         level++;
1207                         phandle = chandle;
1208                         chandle = NULL;
1209                         continue;
1210                 }
1211
1212                 /*
1213                  * We're only interested in objects that we consider 'devices'.
1214                  */
1215                 switch (type) {
1216                 case ACPI_TYPE_DEVICE:
1217                         type = ACPI_BUS_TYPE_DEVICE;
1218                         break;
1219                 case ACPI_TYPE_PROCESSOR:
1220                         type = ACPI_BUS_TYPE_PROCESSOR;
1221                         break;
1222                 case ACPI_TYPE_THERMAL:
1223                         type = ACPI_BUS_TYPE_THERMAL;
1224                         break;
1225                 case ACPI_TYPE_POWER:
1226                         type = ACPI_BUS_TYPE_POWER;
1227                         break;
1228                 default:
1229                         continue;
1230                 }
1231
1232                 status = acpi_bus_add(&child, parent, chandle, type);
1233                 if (ACPI_FAILURE(status))
1234                         continue;
1235
1236                 /*
1237                  * If the device is present, enabled, and functioning then
1238                  * parse its scope (depth-first).  Note that we need to
1239                  * represent absent devices to facilitate PnP notifications
1240                  * -- but only the subtree head (not all of its children,
1241                  * which will be enumerated when the parent is inserted).
1242                  *
1243                  * TBD: Need notifications and other detection mechanisms
1244                  *      in place before we can fully implement this.
1245                  */
1246                 if (child->status.present) {
1247                         status = acpi_get_next_object(ACPI_TYPE_ANY, chandle,
1248                                                       NULL, NULL);
1249                         if (ACPI_SUCCESS(status)) {
1250                                 level++;
1251                                 phandle = chandle;
1252                                 chandle = NULL;
1253                                 parent = child;
1254                         }
1255                 }
1256         }
1257
1258         return_VALUE(0);
1259 }
1260 EXPORT_SYMBOL(acpi_bus_scan);
1261
1262
1263 static int
1264 acpi_bus_trim(struct acpi_device        *start,
1265                 int rmdevice)
1266 {
1267         acpi_status             status;
1268         struct acpi_device      *parent, *child;
1269         acpi_handle             phandle, chandle;
1270         acpi_object_type        type;
1271         u32                     level = 1;
1272         int                     err = 0;
1273
1274         parent  = start;
1275         phandle = start->handle;
1276         child = chandle = NULL;
1277
1278         while ((level > 0) && parent && (!err)) {
1279                 status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
1280                         chandle, &chandle);
1281
1282                 /*
1283                  * If this scope is exhausted then move our way back up.
1284                  */
1285                 if (ACPI_FAILURE(status)) {
1286                         level--;
1287                         chandle = phandle;
1288                         acpi_get_parent(phandle, &phandle);
1289                         child = parent;
1290                         parent = parent->parent;
1291
1292                         if (level == 0)
1293                                 err = acpi_bus_remove(child, rmdevice);
1294                         else
1295                                 err = acpi_bus_remove(child, 1);
1296
1297                         continue;
1298                 }
1299
1300                 status = acpi_get_type(chandle, &type);
1301                 if (ACPI_FAILURE(status)) {
1302                         continue;
1303                 }
1304                 /*
1305                  * If there is a device corresponding to chandle then
1306                  * parse it (depth-first).
1307                  */
1308                 if (acpi_bus_get_device(chandle, &child) == 0) {
1309                         level++;
1310                         phandle = chandle;
1311                         chandle = NULL;
1312                         parent = child;
1313                 }
1314                 continue;
1315         }
1316         return err;
1317 }
1318
1319 static int
1320 acpi_bus_scan_fixed (
1321         struct acpi_device      *root)
1322 {
1323         int                     result = 0;
1324         struct acpi_device      *device = NULL;
1325
1326         ACPI_FUNCTION_TRACE("acpi_bus_scan_fixed");
1327
1328         if (!root)
1329                 return_VALUE(-ENODEV);
1330
1331         /*
1332          * Enumerate all fixed-feature devices.
1333          */
1334         if (acpi_fadt.pwr_button == 0)
1335                 result = acpi_bus_add(&device, acpi_root, 
1336                         NULL, ACPI_BUS_TYPE_POWER_BUTTON);
1337
1338         if (acpi_fadt.sleep_button == 0)
1339                 result = acpi_bus_add(&device, acpi_root, 
1340                         NULL, ACPI_BUS_TYPE_SLEEP_BUTTON);
1341
1342         return_VALUE(result);
1343 }
1344
1345
1346 static int __init acpi_scan_init(void)
1347 {
1348         int result;
1349
1350         ACPI_FUNCTION_TRACE("acpi_scan_init");
1351
1352         if (acpi_disabled)
1353                 return_VALUE(0);
1354
1355         kset_register(&acpi_namespace_kset);
1356
1357         /*
1358          * Create the root device in the bus's device tree
1359          */
1360         result = acpi_bus_add(&acpi_root, NULL, ACPI_ROOT_OBJECT, 
1361                 ACPI_BUS_TYPE_SYSTEM);
1362         if (result)
1363                 goto Done;
1364
1365         /*
1366          * Enumerate devices in the ACPI namespace.
1367          */
1368         result = acpi_bus_scan_fixed(acpi_root);
1369         if (!result) 
1370                 result = acpi_bus_scan(acpi_root);
1371
1372         if (result)
1373                 acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
1374
1375  Done:
1376         return_VALUE(result);
1377 }
1378
1379 subsys_initcall(acpi_scan_init);