[PATCH] driver core: safely unbind drivers for devices not on a bus
[linux-2.6] / drivers / acpi / osl.c
1 /*
2  *  acpi_osl.c - OS-dependent functions ($Revision: 83 $)
3  *
4  *  Copyright (C) 2000       Andrew Henroid
5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or
13  *  (at your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful,
16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  *  GNU General Public License for more details.
19  *
20  *  You should have received a copy of the GNU General Public License
21  *  along with this program; if not, write to the Free Software
22  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
23  *
24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25  *
26  */
27
28 #include <linux/config.h>
29 #include <linux/module.h>
30 #include <linux/kernel.h>
31 #include <linux/slab.h>
32 #include <linux/mm.h>
33 #include <linux/pci.h>
34 #include <linux/smp_lock.h>
35 #include <linux/interrupt.h>
36 #include <linux/kmod.h>
37 #include <linux/delay.h>
38 #include <linux/workqueue.h>
39 #include <linux/nmi.h>
40 #include <acpi/acpi.h>
41 #include <asm/io.h>
42 #include <acpi/acpi_bus.h>
43 #include <acpi/processor.h>
44 #include <asm/uaccess.h>
45
46 #include <linux/efi.h>
47
48 #define _COMPONENT              ACPI_OS_SERVICES
49 ACPI_MODULE_NAME("osl")
50 #define PREFIX          "ACPI: "
51 struct acpi_os_dpc {
52         acpi_osd_exec_callback function;
53         void *context;
54 };
55
56 #ifdef CONFIG_ACPI_CUSTOM_DSDT
57 #include CONFIG_ACPI_CUSTOM_DSDT_FILE
58 #endif
59
60 #ifdef ENABLE_DEBUGGER
61 #include <linux/kdb.h>
62
63 /* stuff for debugger support */
64 int acpi_in_debugger;
65 EXPORT_SYMBOL(acpi_in_debugger);
66
67 extern char line_buf[80];
68 #endif                          /*ENABLE_DEBUGGER */
69
70 int acpi_specific_hotkey_enabled = TRUE;
71 EXPORT_SYMBOL(acpi_specific_hotkey_enabled);
72
73 static unsigned int acpi_irq_irq;
74 static acpi_osd_handler acpi_irq_handler;
75 static void *acpi_irq_context;
76 static struct workqueue_struct *kacpid_wq;
77
78 acpi_status acpi_os_initialize(void)
79 {
80         return AE_OK;
81 }
82
83 acpi_status acpi_os_initialize1(void)
84 {
85         /*
86          * Initialize PCI configuration space access, as we'll need to access
87          * it while walking the namespace (bus 0 and root bridges w/ _BBNs).
88          */
89         if (!raw_pci_ops) {
90                 printk(KERN_ERR PREFIX
91                        "Access to PCI configuration space unavailable\n");
92                 return AE_NULL_ENTRY;
93         }
94         kacpid_wq = create_singlethread_workqueue("kacpid");
95         BUG_ON(!kacpid_wq);
96
97         return AE_OK;
98 }
99
100 acpi_status acpi_os_terminate(void)
101 {
102         if (acpi_irq_handler) {
103                 acpi_os_remove_interrupt_handler(acpi_irq_irq,
104                                                  acpi_irq_handler);
105         }
106
107         destroy_workqueue(kacpid_wq);
108
109         return AE_OK;
110 }
111
112 void acpi_os_printf(const char *fmt, ...)
113 {
114         va_list args;
115         va_start(args, fmt);
116         acpi_os_vprintf(fmt, args);
117         va_end(args);
118 }
119
120 EXPORT_SYMBOL(acpi_os_printf);
121
122 void acpi_os_vprintf(const char *fmt, va_list args)
123 {
124         static char buffer[512];
125
126         vsprintf(buffer, fmt, args);
127
128 #ifdef ENABLE_DEBUGGER
129         if (acpi_in_debugger) {
130                 kdb_printf("%s", buffer);
131         } else {
132                 printk("%s", buffer);
133         }
134 #else
135         printk("%s", buffer);
136 #endif
137 }
138
139 extern int acpi_in_resume;
140 void *acpi_os_allocate(acpi_size size)
141 {
142         if (acpi_in_resume)
143                 return kmalloc(size, GFP_ATOMIC);
144         else
145                 return kmalloc(size, GFP_KERNEL);
146 }
147
148 void acpi_os_free(void *ptr)
149 {
150         kfree(ptr);
151 }
152
153 EXPORT_SYMBOL(acpi_os_free);
154
155 acpi_status acpi_os_get_root_pointer(u32 flags, struct acpi_pointer *addr)
156 {
157         if (efi_enabled) {
158                 addr->pointer_type = ACPI_PHYSICAL_POINTER;
159                 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
160                         addr->pointer.physical = efi.acpi20;
161                 else if (efi.acpi != EFI_INVALID_TABLE_ADDR)
162                         addr->pointer.physical = efi.acpi;
163                 else {
164                         printk(KERN_ERR PREFIX
165                                "System description tables not found\n");
166                         return AE_NOT_FOUND;
167                 }
168         } else {
169                 if (ACPI_FAILURE(acpi_find_root_pointer(flags, addr))) {
170                         printk(KERN_ERR PREFIX
171                                "System description tables not found\n");
172                         return AE_NOT_FOUND;
173                 }
174         }
175
176         return AE_OK;
177 }
178
179 acpi_status
180 acpi_os_map_memory(acpi_physical_address phys, acpi_size size,
181                    void __iomem ** virt)
182 {
183         if (phys > ULONG_MAX) {
184                 printk(KERN_ERR PREFIX "Cannot map memory that high\n");
185                 return AE_BAD_PARAMETER;
186         }
187         /*
188          * ioremap checks to ensure this is in reserved space
189          */
190         *virt = ioremap((unsigned long)phys, size);
191
192         if (!*virt)
193                 return AE_NO_MEMORY;
194
195         return AE_OK;
196 }
197 EXPORT_SYMBOL_GPL(acpi_os_map_memory);
198
199 void acpi_os_unmap_memory(void __iomem * virt, acpi_size size)
200 {
201         iounmap(virt);
202 }
203 EXPORT_SYMBOL_GPL(acpi_os_unmap_memory);
204
205 #ifdef ACPI_FUTURE_USAGE
206 acpi_status
207 acpi_os_get_physical_address(void *virt, acpi_physical_address * phys)
208 {
209         if (!phys || !virt)
210                 return AE_BAD_PARAMETER;
211
212         *phys = virt_to_phys(virt);
213
214         return AE_OK;
215 }
216 #endif
217
218 #define ACPI_MAX_OVERRIDE_LEN 100
219
220 static char acpi_os_name[ACPI_MAX_OVERRIDE_LEN];
221
222 acpi_status
223 acpi_os_predefined_override(const struct acpi_predefined_names *init_val,
224                             acpi_string * new_val)
225 {
226         if (!init_val || !new_val)
227                 return AE_BAD_PARAMETER;
228
229         *new_val = NULL;
230         if (!memcmp(init_val->name, "_OS_", 4) && strlen(acpi_os_name)) {
231                 printk(KERN_INFO PREFIX "Overriding _OS definition to '%s'\n",
232                        acpi_os_name);
233                 *new_val = acpi_os_name;
234         }
235
236         return AE_OK;
237 }
238
239 acpi_status
240 acpi_os_table_override(struct acpi_table_header * existing_table,
241                        struct acpi_table_header ** new_table)
242 {
243         if (!existing_table || !new_table)
244                 return AE_BAD_PARAMETER;
245
246 #ifdef CONFIG_ACPI_CUSTOM_DSDT
247         if (strncmp(existing_table->signature, "DSDT", 4) == 0)
248                 *new_table = (struct acpi_table_header *)AmlCode;
249         else
250                 *new_table = NULL;
251 #else
252         *new_table = NULL;
253 #endif
254         return AE_OK;
255 }
256
257 static irqreturn_t acpi_irq(int irq, void *dev_id, struct pt_regs *regs)
258 {
259         return (*acpi_irq_handler) (acpi_irq_context) ? IRQ_HANDLED : IRQ_NONE;
260 }
261
262 acpi_status
263 acpi_os_install_interrupt_handler(u32 gsi, acpi_osd_handler handler,
264                                   void *context)
265 {
266         unsigned int irq;
267
268         /*
269          * Ignore the GSI from the core, and use the value in our copy of the
270          * FADT. It may not be the same if an interrupt source override exists
271          * for the SCI.
272          */
273         gsi = acpi_fadt.sci_int;
274         if (acpi_gsi_to_irq(gsi, &irq) < 0) {
275                 printk(KERN_ERR PREFIX "SCI (ACPI GSI %d) not registered\n",
276                        gsi);
277                 return AE_OK;
278         }
279
280         acpi_irq_handler = handler;
281         acpi_irq_context = context;
282         if (request_irq(irq, acpi_irq, SA_SHIRQ, "acpi", acpi_irq)) {
283                 printk(KERN_ERR PREFIX "SCI (IRQ%d) allocation failed\n", irq);
284                 return AE_NOT_ACQUIRED;
285         }
286         acpi_irq_irq = irq;
287
288         return AE_OK;
289 }
290
291 acpi_status acpi_os_remove_interrupt_handler(u32 irq, acpi_osd_handler handler)
292 {
293         if (irq) {
294                 free_irq(irq, acpi_irq);
295                 acpi_irq_handler = NULL;
296                 acpi_irq_irq = 0;
297         }
298
299         return AE_OK;
300 }
301
302 /*
303  * Running in interpreter thread context, safe to sleep
304  */
305
306 void acpi_os_sleep(acpi_integer ms)
307 {
308         schedule_timeout_interruptible(msecs_to_jiffies(ms));
309 }
310
311 EXPORT_SYMBOL(acpi_os_sleep);
312
313 void acpi_os_stall(u32 us)
314 {
315         while (us) {
316                 u32 delay = 1000;
317
318                 if (delay > us)
319                         delay = us;
320                 udelay(delay);
321                 touch_nmi_watchdog();
322                 us -= delay;
323         }
324 }
325
326 EXPORT_SYMBOL(acpi_os_stall);
327
328 /*
329  * Support ACPI 3.0 AML Timer operand
330  * Returns 64-bit free-running, monotonically increasing timer
331  * with 100ns granularity
332  */
333 u64 acpi_os_get_timer(void)
334 {
335         static u64 t;
336
337 #ifdef  CONFIG_HPET
338         /* TBD: use HPET if available */
339 #endif
340
341 #ifdef  CONFIG_X86_PM_TIMER
342         /* TBD: default to PM timer if HPET was not available */
343 #endif
344         if (!t)
345                 printk(KERN_ERR PREFIX "acpi_os_get_timer() TBD\n");
346
347         return ++t;
348 }
349
350 acpi_status acpi_os_read_port(acpi_io_address port, u32 * value, u32 width)
351 {
352         u32 dummy;
353
354         if (!value)
355                 value = &dummy;
356
357         switch (width) {
358         case 8:
359                 *(u8 *) value = inb(port);
360                 break;
361         case 16:
362                 *(u16 *) value = inw(port);
363                 break;
364         case 32:
365                 *(u32 *) value = inl(port);
366                 break;
367         default:
368                 BUG();
369         }
370
371         return AE_OK;
372 }
373
374 EXPORT_SYMBOL(acpi_os_read_port);
375
376 acpi_status acpi_os_write_port(acpi_io_address port, u32 value, u32 width)
377 {
378         switch (width) {
379         case 8:
380                 outb(value, port);
381                 break;
382         case 16:
383                 outw(value, port);
384                 break;
385         case 32:
386                 outl(value, port);
387                 break;
388         default:
389                 BUG();
390         }
391
392         return AE_OK;
393 }
394
395 EXPORT_SYMBOL(acpi_os_write_port);
396
397 acpi_status
398 acpi_os_read_memory(acpi_physical_address phys_addr, u32 * value, u32 width)
399 {
400         u32 dummy;
401         void __iomem *virt_addr;
402
403         virt_addr = ioremap(phys_addr, width);
404         if (!value)
405                 value = &dummy;
406
407         switch (width) {
408         case 8:
409                 *(u8 *) value = readb(virt_addr);
410                 break;
411         case 16:
412                 *(u16 *) value = readw(virt_addr);
413                 break;
414         case 32:
415                 *(u32 *) value = readl(virt_addr);
416                 break;
417         default:
418                 BUG();
419         }
420
421         iounmap(virt_addr);
422
423         return AE_OK;
424 }
425
426 acpi_status
427 acpi_os_write_memory(acpi_physical_address phys_addr, u32 value, u32 width)
428 {
429         void __iomem *virt_addr;
430
431         virt_addr = ioremap(phys_addr, width);
432
433         switch (width) {
434         case 8:
435                 writeb(value, virt_addr);
436                 break;
437         case 16:
438                 writew(value, virt_addr);
439                 break;
440         case 32:
441                 writel(value, virt_addr);
442                 break;
443         default:
444                 BUG();
445         }
446
447         iounmap(virt_addr);
448
449         return AE_OK;
450 }
451
452 acpi_status
453 acpi_os_read_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
454                                void *value, u32 width)
455 {
456         int result, size;
457
458         if (!value)
459                 return AE_BAD_PARAMETER;
460
461         switch (width) {
462         case 8:
463                 size = 1;
464                 break;
465         case 16:
466                 size = 2;
467                 break;
468         case 32:
469                 size = 4;
470                 break;
471         default:
472                 return AE_ERROR;
473         }
474
475         BUG_ON(!raw_pci_ops);
476
477         result = raw_pci_ops->read(pci_id->segment, pci_id->bus,
478                                    PCI_DEVFN(pci_id->device, pci_id->function),
479                                    reg, size, value);
480
481         return (result ? AE_ERROR : AE_OK);
482 }
483
484 EXPORT_SYMBOL(acpi_os_read_pci_configuration);
485
486 acpi_status
487 acpi_os_write_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
488                                 acpi_integer value, u32 width)
489 {
490         int result, size;
491
492         switch (width) {
493         case 8:
494                 size = 1;
495                 break;
496         case 16:
497                 size = 2;
498                 break;
499         case 32:
500                 size = 4;
501                 break;
502         default:
503                 return AE_ERROR;
504         }
505
506         BUG_ON(!raw_pci_ops);
507
508         result = raw_pci_ops->write(pci_id->segment, pci_id->bus,
509                                     PCI_DEVFN(pci_id->device, pci_id->function),
510                                     reg, size, value);
511
512         return (result ? AE_ERROR : AE_OK);
513 }
514
515 /* TODO: Change code to take advantage of driver model more */
516 static void acpi_os_derive_pci_id_2(acpi_handle rhandle,        /* upper bound  */
517                                     acpi_handle chandle,        /* current node */
518                                     struct acpi_pci_id **id,
519                                     int *is_bridge, u8 * bus_number)
520 {
521         acpi_handle handle;
522         struct acpi_pci_id *pci_id = *id;
523         acpi_status status;
524         unsigned long temp;
525         acpi_object_type type;
526         u8 tu8;
527
528         acpi_get_parent(chandle, &handle);
529         if (handle != rhandle) {
530                 acpi_os_derive_pci_id_2(rhandle, handle, &pci_id, is_bridge,
531                                         bus_number);
532
533                 status = acpi_get_type(handle, &type);
534                 if ((ACPI_FAILURE(status)) || (type != ACPI_TYPE_DEVICE))
535                         return;
536
537                 status =
538                     acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL,
539                                           &temp);
540                 if (ACPI_SUCCESS(status)) {
541                         pci_id->device = ACPI_HIWORD(ACPI_LODWORD(temp));
542                         pci_id->function = ACPI_LOWORD(ACPI_LODWORD(temp));
543
544                         if (*is_bridge)
545                                 pci_id->bus = *bus_number;
546
547                         /* any nicer way to get bus number of bridge ? */
548                         status =
549                             acpi_os_read_pci_configuration(pci_id, 0x0e, &tu8,
550                                                            8);
551                         if (ACPI_SUCCESS(status)
552                             && ((tu8 & 0x7f) == 1 || (tu8 & 0x7f) == 2)) {
553                                 status =
554                                     acpi_os_read_pci_configuration(pci_id, 0x18,
555                                                                    &tu8, 8);
556                                 if (!ACPI_SUCCESS(status)) {
557                                         /* Certainly broken...  FIX ME */
558                                         return;
559                                 }
560                                 *is_bridge = 1;
561                                 pci_id->bus = tu8;
562                                 status =
563                                     acpi_os_read_pci_configuration(pci_id, 0x19,
564                                                                    &tu8, 8);
565                                 if (ACPI_SUCCESS(status)) {
566                                         *bus_number = tu8;
567                                 }
568                         } else
569                                 *is_bridge = 0;
570                 }
571         }
572 }
573
574 void acpi_os_derive_pci_id(acpi_handle rhandle, /* upper bound  */
575                            acpi_handle chandle, /* current node */
576                            struct acpi_pci_id **id)
577 {
578         int is_bridge = 1;
579         u8 bus_number = (*id)->bus;
580
581         acpi_os_derive_pci_id_2(rhandle, chandle, id, &is_bridge, &bus_number);
582 }
583
584 static void acpi_os_execute_deferred(void *context)
585 {
586         struct acpi_os_dpc *dpc = NULL;
587
588         ACPI_FUNCTION_TRACE("os_execute_deferred");
589
590         dpc = (struct acpi_os_dpc *)context;
591         if (!dpc) {
592                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid (NULL) context.\n"));
593                 return_VOID;
594         }
595
596         dpc->function(dpc->context);
597
598         kfree(dpc);
599
600         return_VOID;
601 }
602
603 acpi_status
604 acpi_os_queue_for_execution(u32 priority,
605                             acpi_osd_exec_callback function, void *context)
606 {
607         acpi_status status = AE_OK;
608         struct acpi_os_dpc *dpc;
609         struct work_struct *task;
610
611         ACPI_FUNCTION_TRACE("os_queue_for_execution");
612
613         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
614                           "Scheduling function [%p(%p)] for deferred execution.\n",
615                           function, context));
616
617         if (!function)
618                 return_ACPI_STATUS(AE_BAD_PARAMETER);
619
620         /*
621          * Allocate/initialize DPC structure.  Note that this memory will be
622          * freed by the callee.  The kernel handles the tq_struct list  in a
623          * way that allows us to also free its memory inside the callee.
624          * Because we may want to schedule several tasks with different
625          * parameters we can't use the approach some kernel code uses of
626          * having a static tq_struct.
627          * We can save time and code by allocating the DPC and tq_structs
628          * from the same memory.
629          */
630
631         dpc =
632             kmalloc(sizeof(struct acpi_os_dpc) + sizeof(struct work_struct),
633                     GFP_ATOMIC);
634         if (!dpc)
635                 return_ACPI_STATUS(AE_NO_MEMORY);
636
637         dpc->function = function;
638         dpc->context = context;
639
640         task = (void *)(dpc + 1);
641         INIT_WORK(task, acpi_os_execute_deferred, (void *)dpc);
642
643         if (!queue_work(kacpid_wq, task)) {
644                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
645                                   "Call to queue_work() failed.\n"));
646                 kfree(dpc);
647                 status = AE_ERROR;
648         }
649
650         return_ACPI_STATUS(status);
651 }
652
653 EXPORT_SYMBOL(acpi_os_queue_for_execution);
654
655 void acpi_os_wait_events_complete(void *context)
656 {
657         flush_workqueue(kacpid_wq);
658 }
659
660 EXPORT_SYMBOL(acpi_os_wait_events_complete);
661
662 /*
663  * Allocate the memory for a spinlock and initialize it.
664  */
665 acpi_status acpi_os_create_lock(acpi_handle * out_handle)
666 {
667         spinlock_t *lock_ptr;
668
669         ACPI_FUNCTION_TRACE("os_create_lock");
670
671         lock_ptr = acpi_os_allocate(sizeof(spinlock_t));
672
673         spin_lock_init(lock_ptr);
674
675         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Creating spinlock[%p].\n", lock_ptr));
676
677         *out_handle = lock_ptr;
678
679         return_ACPI_STATUS(AE_OK);
680 }
681
682 /*
683  * Deallocate the memory for a spinlock.
684  */
685 void acpi_os_delete_lock(acpi_handle handle)
686 {
687         ACPI_FUNCTION_TRACE("os_create_lock");
688
689         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting spinlock[%p].\n", handle));
690
691         acpi_os_free(handle);
692
693         return_VOID;
694 }
695
696 acpi_status
697 acpi_os_create_semaphore(u32 max_units, u32 initial_units, acpi_handle * handle)
698 {
699         struct semaphore *sem = NULL;
700
701         ACPI_FUNCTION_TRACE("os_create_semaphore");
702
703         sem = acpi_os_allocate(sizeof(struct semaphore));
704         if (!sem)
705                 return_ACPI_STATUS(AE_NO_MEMORY);
706         memset(sem, 0, sizeof(struct semaphore));
707
708         sema_init(sem, initial_units);
709
710         *handle = (acpi_handle *) sem;
711
712         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Creating semaphore[%p|%d].\n",
713                           *handle, initial_units));
714
715         return_ACPI_STATUS(AE_OK);
716 }
717
718 EXPORT_SYMBOL(acpi_os_create_semaphore);
719
720 /*
721  * TODO: A better way to delete semaphores?  Linux doesn't have a
722  * 'delete_semaphore()' function -- may result in an invalid
723  * pointer dereference for non-synchronized consumers.  Should
724  * we at least check for blocked threads and signal/cancel them?
725  */
726
727 acpi_status acpi_os_delete_semaphore(acpi_handle handle)
728 {
729         struct semaphore *sem = (struct semaphore *)handle;
730
731         ACPI_FUNCTION_TRACE("os_delete_semaphore");
732
733         if (!sem)
734                 return_ACPI_STATUS(AE_BAD_PARAMETER);
735
736         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting semaphore[%p].\n", handle));
737
738         acpi_os_free(sem);
739         sem = NULL;
740
741         return_ACPI_STATUS(AE_OK);
742 }
743
744 EXPORT_SYMBOL(acpi_os_delete_semaphore);
745
746 /*
747  * TODO: The kernel doesn't have a 'down_timeout' function -- had to
748  * improvise.  The process is to sleep for one scheduler quantum
749  * until the semaphore becomes available.  Downside is that this
750  * may result in starvation for timeout-based waits when there's
751  * lots of semaphore activity.
752  *
753  * TODO: Support for units > 1?
754  */
755 acpi_status acpi_os_wait_semaphore(acpi_handle handle, u32 units, u16 timeout)
756 {
757         acpi_status status = AE_OK;
758         struct semaphore *sem = (struct semaphore *)handle;
759         int ret = 0;
760
761         ACPI_FUNCTION_TRACE("os_wait_semaphore");
762
763         if (!sem || (units < 1))
764                 return_ACPI_STATUS(AE_BAD_PARAMETER);
765
766         if (units > 1)
767                 return_ACPI_STATUS(AE_SUPPORT);
768
769         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Waiting for semaphore[%p|%d|%d]\n",
770                           handle, units, timeout));
771
772         if (in_atomic())
773                 timeout = 0;
774
775         switch (timeout) {
776                 /*
777                  * No Wait:
778                  * --------
779                  * A zero timeout value indicates that we shouldn't wait - just
780                  * acquire the semaphore if available otherwise return AE_TIME
781                  * (a.k.a. 'would block').
782                  */
783         case 0:
784                 if (down_trylock(sem))
785                         status = AE_TIME;
786                 break;
787
788                 /*
789                  * Wait Indefinitely:
790                  * ------------------
791                  */
792         case ACPI_WAIT_FOREVER:
793                 down(sem);
794                 break;
795
796                 /*
797                  * Wait w/ Timeout:
798                  * ----------------
799                  */
800         default:
801                 // TODO: A better timeout algorithm?
802                 {
803                         int i = 0;
804                         static const int quantum_ms = 1000 / HZ;
805
806                         ret = down_trylock(sem);
807                         for (i = timeout; (i > 0 && ret != 0); i -= quantum_ms) {
808                                 schedule_timeout_interruptible(1);
809                                 ret = down_trylock(sem);
810                         }
811
812                         if (ret != 0)
813                                 status = AE_TIME;
814                 }
815                 break;
816         }
817
818         if (ACPI_FAILURE(status)) {
819                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
820                                   "Failed to acquire semaphore[%p|%d|%d], %s\n",
821                                   handle, units, timeout,
822                                   acpi_format_exception(status)));
823         } else {
824                 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
825                                   "Acquired semaphore[%p|%d|%d]\n", handle,
826                                   units, timeout));
827         }
828
829         return_ACPI_STATUS(status);
830 }
831
832 EXPORT_SYMBOL(acpi_os_wait_semaphore);
833
834 /*
835  * TODO: Support for units > 1?
836  */
837 acpi_status acpi_os_signal_semaphore(acpi_handle handle, u32 units)
838 {
839         struct semaphore *sem = (struct semaphore *)handle;
840
841         ACPI_FUNCTION_TRACE("os_signal_semaphore");
842
843         if (!sem || (units < 1))
844                 return_ACPI_STATUS(AE_BAD_PARAMETER);
845
846         if (units > 1)
847                 return_ACPI_STATUS(AE_SUPPORT);
848
849         ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Signaling semaphore[%p|%d]\n", handle,
850                           units));
851
852         up(sem);
853
854         return_ACPI_STATUS(AE_OK);
855 }
856
857 EXPORT_SYMBOL(acpi_os_signal_semaphore);
858
859 #ifdef ACPI_FUTURE_USAGE
860 u32 acpi_os_get_line(char *buffer)
861 {
862
863 #ifdef ENABLE_DEBUGGER
864         if (acpi_in_debugger) {
865                 u32 chars;
866
867                 kdb_read(buffer, sizeof(line_buf));
868
869                 /* remove the CR kdb includes */
870                 chars = strlen(buffer) - 1;
871                 buffer[chars] = '\0';
872         }
873 #endif
874
875         return 0;
876 }
877 #endif                          /*  ACPI_FUTURE_USAGE  */
878
879 /* Assumes no unreadable holes inbetween */
880 u8 acpi_os_readable(void *ptr, acpi_size len)
881 {
882 #if defined(__i386__) || defined(__x86_64__)
883         char tmp;
884         return !__get_user(tmp, (char __user *)ptr)
885             && !__get_user(tmp, (char __user *)ptr + len - 1);
886 #endif
887         return 1;
888 }
889
890 #ifdef ACPI_FUTURE_USAGE
891 u8 acpi_os_writable(void *ptr, acpi_size len)
892 {
893         /* could do dummy write (racy) or a kernel page table lookup.
894            The later may be difficult at early boot when kmap doesn't work yet. */
895         return 1;
896 }
897 #endif
898
899 u32 acpi_os_get_thread_id(void)
900 {
901         if (!in_atomic())
902                 return current->pid;
903
904         return 0;
905 }
906
907 acpi_status acpi_os_signal(u32 function, void *info)
908 {
909         switch (function) {
910         case ACPI_SIGNAL_FATAL:
911                 printk(KERN_ERR PREFIX "Fatal opcode executed\n");
912                 break;
913         case ACPI_SIGNAL_BREAKPOINT:
914                 /*
915                  * AML Breakpoint
916                  * ACPI spec. says to treat it as a NOP unless
917                  * you are debugging.  So if/when we integrate
918                  * AML debugger into the kernel debugger its
919                  * hook will go here.  But until then it is
920                  * not useful to print anything on breakpoints.
921                  */
922                 break;
923         default:
924                 break;
925         }
926
927         return AE_OK;
928 }
929
930 EXPORT_SYMBOL(acpi_os_signal);
931
932 static int __init acpi_os_name_setup(char *str)
933 {
934         char *p = acpi_os_name;
935         int count = ACPI_MAX_OVERRIDE_LEN - 1;
936
937         if (!str || !*str)
938                 return 0;
939
940         for (; count-- && str && *str; str++) {
941                 if (isalnum(*str) || *str == ' ' || *str == ':')
942                         *p++ = *str;
943                 else if (*str == '\'' || *str == '"')
944                         continue;
945                 else
946                         break;
947         }
948         *p = 0;
949
950         return 1;
951
952 }
953
954 __setup("acpi_os_name=", acpi_os_name_setup);
955
956 /*
957  * _OSI control
958  * empty string disables _OSI
959  * TBD additional string adds to _OSI
960  */
961 static int __init acpi_osi_setup(char *str)
962 {
963         if (str == NULL || *str == '\0') {
964                 printk(KERN_INFO PREFIX "_OSI method disabled\n");
965                 acpi_gbl_create_osi_method = FALSE;
966         } else {
967                 /* TBD */
968                 printk(KERN_ERR PREFIX "_OSI additional string ignored -- %s\n",
969                        str);
970         }
971
972         return 1;
973 }
974
975 __setup("acpi_osi=", acpi_osi_setup);
976
977 /* enable serialization to combat AE_ALREADY_EXISTS errors */
978 static int __init acpi_serialize_setup(char *str)
979 {
980         printk(KERN_INFO PREFIX "serialize enabled\n");
981
982         acpi_gbl_all_methods_serialized = TRUE;
983
984         return 1;
985 }
986
987 __setup("acpi_serialize", acpi_serialize_setup);
988
989 /*
990  * Wake and Run-Time GPES are expected to be separate.
991  * We disable wake-GPEs at run-time to prevent spurious
992  * interrupts.
993  *
994  * However, if a system exists that shares Wake and
995  * Run-time events on the same GPE this flag is available
996  * to tell Linux to keep the wake-time GPEs enabled at run-time.
997  */
998 static int __init acpi_wake_gpes_always_on_setup(char *str)
999 {
1000         printk(KERN_INFO PREFIX "wake GPEs not disabled\n");
1001
1002         acpi_gbl_leave_wake_gpes_disabled = FALSE;
1003
1004         return 1;
1005 }
1006
1007 __setup("acpi_wake_gpes_always_on", acpi_wake_gpes_always_on_setup);
1008
1009 static int __init acpi_hotkey_setup(char *str)
1010 {
1011         acpi_specific_hotkey_enabled = FALSE;
1012         return 1;
1013 }
1014
1015 __setup("acpi_generic_hotkey", acpi_hotkey_setup);
1016
1017 /*
1018  * max_cstate is defined in the base kernel so modules can
1019  * change it w/o depending on the state of the processor module.
1020  */
1021 unsigned int max_cstate = ACPI_PROCESSOR_MAX_POWER;
1022
1023 EXPORT_SYMBOL(max_cstate);
1024
1025 /*
1026  * Acquire a spinlock.
1027  *
1028  * handle is a pointer to the spinlock_t.
1029  */
1030
1031 acpi_cpu_flags acpi_os_acquire_lock(acpi_handle handle)
1032 {
1033         acpi_cpu_flags flags;
1034         spin_lock_irqsave((spinlock_t *) handle, flags);
1035         return flags;
1036 }
1037
1038 /*
1039  * Release a spinlock. See above.
1040  */
1041
1042 void acpi_os_release_lock(acpi_handle handle, acpi_cpu_flags flags)
1043 {
1044         spin_unlock_irqrestore((spinlock_t *) handle, flags);
1045 }
1046
1047 #ifndef ACPI_USE_LOCAL_CACHE
1048
1049 /*******************************************************************************
1050  *
1051  * FUNCTION:    acpi_os_create_cache
1052  *
1053  * PARAMETERS:  CacheName       - Ascii name for the cache
1054  *              ObjectSize      - Size of each cached object
1055  *              MaxDepth        - Maximum depth of the cache (in objects)
1056  *              ReturnCache     - Where the new cache object is returned
1057  *
1058  * RETURN:      Status
1059  *
1060  * DESCRIPTION: Create a cache object
1061  *
1062  ******************************************************************************/
1063
1064 acpi_status
1065 acpi_os_create_cache(char *name, u16 size, u16 depth, acpi_cache_t ** cache)
1066 {
1067         *cache = kmem_cache_create(name, size, 0, 0, NULL, NULL);
1068         return AE_OK;
1069 }
1070
1071 /*******************************************************************************
1072  *
1073  * FUNCTION:    acpi_os_purge_cache
1074  *
1075  * PARAMETERS:  Cache           - Handle to cache object
1076  *
1077  * RETURN:      Status
1078  *
1079  * DESCRIPTION: Free all objects within the requested cache.
1080  *
1081  ******************************************************************************/
1082
1083 acpi_status acpi_os_purge_cache(acpi_cache_t * cache)
1084 {
1085         (void)kmem_cache_shrink(cache);
1086         return (AE_OK);
1087 }
1088
1089 /*******************************************************************************
1090  *
1091  * FUNCTION:    acpi_os_delete_cache
1092  *
1093  * PARAMETERS:  Cache           - Handle to cache object
1094  *
1095  * RETURN:      Status
1096  *
1097  * DESCRIPTION: Free all objects within the requested cache and delete the
1098  *              cache object.
1099  *
1100  ******************************************************************************/
1101
1102 acpi_status acpi_os_delete_cache(acpi_cache_t * cache)
1103 {
1104         (void)kmem_cache_destroy(cache);
1105         return (AE_OK);
1106 }
1107
1108 /*******************************************************************************
1109  *
1110  * FUNCTION:    acpi_os_release_object
1111  *
1112  * PARAMETERS:  Cache       - Handle to cache object
1113  *              Object      - The object to be released
1114  *
1115  * RETURN:      None
1116  *
1117  * DESCRIPTION: Release an object to the specified cache.  If cache is full,
1118  *              the object is deleted.
1119  *
1120  ******************************************************************************/
1121
1122 acpi_status acpi_os_release_object(acpi_cache_t * cache, void *object)
1123 {
1124         kmem_cache_free(cache, object);
1125         return (AE_OK);
1126 }
1127
1128 /*******************************************************************************
1129  *
1130  * FUNCTION:    acpi_os_acquire_object
1131  *
1132  * PARAMETERS:  Cache           - Handle to cache object
1133  *              ReturnObject    - Where the object is returned
1134  *
1135  * RETURN:      Status
1136  *
1137  * DESCRIPTION: Get an object from the specified cache.  If cache is empty,
1138  *              the object is allocated.
1139  *
1140  ******************************************************************************/
1141
1142 void *acpi_os_acquire_object(acpi_cache_t * cache)
1143 {
1144         void *object = kmem_cache_alloc(cache, GFP_KERNEL);
1145         WARN_ON(!object);
1146         return object;
1147 }
1148
1149 #endif