Merge tag 'drm/tegra/for-3.16-rc1' of git://anongit.freedesktop.org/tegra/linux into...
[firefly-linux-kernel-4.4.55.git] / drivers / acpi / bus.c
1 /*
2  *  acpi_bus.c - ACPI Bus Driver ($Revision: 80 $)
3  *
4  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
5  *
6  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2 of the License, or (at
11  *  your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful, but
14  *  WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  *  General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License along
19  *  with this program; if not, write to the Free Software Foundation, Inc.,
20  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
21  *
22  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23  */
24
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/ioport.h>
28 #include <linux/kernel.h>
29 #include <linux/list.h>
30 #include <linux/sched.h>
31 #include <linux/pm.h>
32 #include <linux/device.h>
33 #include <linux/proc_fs.h>
34 #include <linux/acpi.h>
35 #include <linux/slab.h>
36 #include <linux/regulator/machine.h>
37 #ifdef CONFIG_X86
38 #include <asm/mpspec.h>
39 #endif
40 #include <linux/pci.h>
41 #include <acpi/apei.h>
42 #include <linux/dmi.h>
43 #include <linux/suspend.h>
44
45 #include "internal.h"
46
47 #define _COMPONENT              ACPI_BUS_COMPONENT
48 ACPI_MODULE_NAME("bus");
49
50 struct acpi_device *acpi_root;
51 struct proc_dir_entry *acpi_root_dir;
52 EXPORT_SYMBOL(acpi_root_dir);
53
54 #ifdef CONFIG_X86
55 static int set_copy_dsdt(const struct dmi_system_id *id)
56 {
57         printk(KERN_NOTICE "%s detected - "
58                 "force copy of DSDT to local memory\n", id->ident);
59         acpi_gbl_copy_dsdt_locally = 1;
60         return 0;
61 }
62
63 static struct dmi_system_id dsdt_dmi_table[] __initdata = {
64         /*
65          * Invoke DSDT corruption work-around on all Toshiba Satellite.
66          * https://bugzilla.kernel.org/show_bug.cgi?id=14679
67          */
68         {
69          .callback = set_copy_dsdt,
70          .ident = "TOSHIBA Satellite",
71          .matches = {
72                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
73                 DMI_MATCH(DMI_PRODUCT_NAME, "Satellite"),
74                 },
75         },
76         {}
77 };
78 #else
79 static struct dmi_system_id dsdt_dmi_table[] __initdata = {
80         {}
81 };
82 #endif
83
84 /* --------------------------------------------------------------------------
85                                 Device Management
86    -------------------------------------------------------------------------- */
87
88 acpi_status acpi_bus_get_status_handle(acpi_handle handle,
89                                        unsigned long long *sta)
90 {
91         acpi_status status;
92
93         status = acpi_evaluate_integer(handle, "_STA", NULL, sta);
94         if (ACPI_SUCCESS(status))
95                 return AE_OK;
96
97         if (status == AE_NOT_FOUND) {
98                 *sta = ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
99                        ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING;
100                 return AE_OK;
101         }
102         return status;
103 }
104
105 int acpi_bus_get_status(struct acpi_device *device)
106 {
107         acpi_status status;
108         unsigned long long sta;
109
110         status = acpi_bus_get_status_handle(device->handle, &sta);
111         if (ACPI_FAILURE(status))
112                 return -ENODEV;
113
114         acpi_set_device_status(device, sta);
115
116         if (device->status.functional && !device->status.present) {
117                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]: "
118                        "functional but not present;\n",
119                         device->pnp.bus_id, (u32)sta));
120         }
121
122         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n",
123                           device->pnp.bus_id, (u32)sta));
124         return 0;
125 }
126 EXPORT_SYMBOL(acpi_bus_get_status);
127
128 void acpi_bus_private_data_handler(acpi_handle handle,
129                                    void *context)
130 {
131         return;
132 }
133 EXPORT_SYMBOL(acpi_bus_private_data_handler);
134
135 int acpi_bus_get_private_data(acpi_handle handle, void **data)
136 {
137         acpi_status status;
138
139         if (!*data)
140                 return -EINVAL;
141
142         status = acpi_get_data(handle, acpi_bus_private_data_handler, data);
143         if (ACPI_FAILURE(status) || !*data) {
144                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
145                                 handle));
146                 return -ENODEV;
147         }
148
149         return 0;
150 }
151 EXPORT_SYMBOL(acpi_bus_get_private_data);
152
153 void acpi_bus_no_hotplug(acpi_handle handle)
154 {
155         struct acpi_device *adev = NULL;
156
157         acpi_bus_get_device(handle, &adev);
158         if (adev)
159                 adev->flags.no_hotplug = true;
160 }
161 EXPORT_SYMBOL_GPL(acpi_bus_no_hotplug);
162
163 static void acpi_print_osc_error(acpi_handle handle,
164         struct acpi_osc_context *context, char *error)
165 {
166         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER};
167         int i;
168
169         if (ACPI_FAILURE(acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer)))
170                 printk(KERN_DEBUG "%s\n", error);
171         else {
172                 printk(KERN_DEBUG "%s:%s\n", (char *)buffer.pointer, error);
173                 kfree(buffer.pointer);
174         }
175         printk(KERN_DEBUG"_OSC request data:");
176         for (i = 0; i < context->cap.length; i += sizeof(u32))
177                 printk("%x ", *((u32 *)(context->cap.pointer + i)));
178         printk("\n");
179 }
180
181 acpi_status acpi_str_to_uuid(char *str, u8 *uuid)
182 {
183         int i;
184         static int opc_map_to_uuid[16] = {6, 4, 2, 0, 11, 9, 16, 14, 19, 21,
185                 24, 26, 28, 30, 32, 34};
186
187         if (strlen(str) != 36)
188                 return AE_BAD_PARAMETER;
189         for (i = 0; i < 36; i++) {
190                 if (i == 8 || i == 13 || i == 18 || i == 23) {
191                         if (str[i] != '-')
192                                 return AE_BAD_PARAMETER;
193                 } else if (!isxdigit(str[i]))
194                         return AE_BAD_PARAMETER;
195         }
196         for (i = 0; i < 16; i++) {
197                 uuid[i] = hex_to_bin(str[opc_map_to_uuid[i]]) << 4;
198                 uuid[i] |= hex_to_bin(str[opc_map_to_uuid[i] + 1]);
199         }
200         return AE_OK;
201 }
202 EXPORT_SYMBOL_GPL(acpi_str_to_uuid);
203
204 acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context)
205 {
206         acpi_status status;
207         struct acpi_object_list input;
208         union acpi_object in_params[4];
209         union acpi_object *out_obj;
210         u8 uuid[16];
211         u32 errors;
212         struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
213
214         if (!context)
215                 return AE_ERROR;
216         if (ACPI_FAILURE(acpi_str_to_uuid(context->uuid_str, uuid)))
217                 return AE_ERROR;
218         context->ret.length = ACPI_ALLOCATE_BUFFER;
219         context->ret.pointer = NULL;
220
221         /* Setting up input parameters */
222         input.count = 4;
223         input.pointer = in_params;
224         in_params[0].type               = ACPI_TYPE_BUFFER;
225         in_params[0].buffer.length      = 16;
226         in_params[0].buffer.pointer     = uuid;
227         in_params[1].type               = ACPI_TYPE_INTEGER;
228         in_params[1].integer.value      = context->rev;
229         in_params[2].type               = ACPI_TYPE_INTEGER;
230         in_params[2].integer.value      = context->cap.length/sizeof(u32);
231         in_params[3].type               = ACPI_TYPE_BUFFER;
232         in_params[3].buffer.length      = context->cap.length;
233         in_params[3].buffer.pointer     = context->cap.pointer;
234
235         status = acpi_evaluate_object(handle, "_OSC", &input, &output);
236         if (ACPI_FAILURE(status))
237                 return status;
238
239         if (!output.length)
240                 return AE_NULL_OBJECT;
241
242         out_obj = output.pointer;
243         if (out_obj->type != ACPI_TYPE_BUFFER
244                 || out_obj->buffer.length != context->cap.length) {
245                 acpi_print_osc_error(handle, context,
246                         "_OSC evaluation returned wrong type");
247                 status = AE_TYPE;
248                 goto out_kfree;
249         }
250         /* Need to ignore the bit0 in result code */
251         errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
252         if (errors) {
253                 if (errors & OSC_REQUEST_ERROR)
254                         acpi_print_osc_error(handle, context,
255                                 "_OSC request failed");
256                 if (errors & OSC_INVALID_UUID_ERROR)
257                         acpi_print_osc_error(handle, context,
258                                 "_OSC invalid UUID");
259                 if (errors & OSC_INVALID_REVISION_ERROR)
260                         acpi_print_osc_error(handle, context,
261                                 "_OSC invalid revision");
262                 if (errors & OSC_CAPABILITIES_MASK_ERROR) {
263                         if (((u32 *)context->cap.pointer)[OSC_QUERY_DWORD]
264                             & OSC_QUERY_ENABLE)
265                                 goto out_success;
266                         status = AE_SUPPORT;
267                         goto out_kfree;
268                 }
269                 status = AE_ERROR;
270                 goto out_kfree;
271         }
272 out_success:
273         context->ret.length = out_obj->buffer.length;
274         context->ret.pointer = kmemdup(out_obj->buffer.pointer,
275                                        context->ret.length, GFP_KERNEL);
276         if (!context->ret.pointer) {
277                 status =  AE_NO_MEMORY;
278                 goto out_kfree;
279         }
280         status =  AE_OK;
281
282 out_kfree:
283         kfree(output.pointer);
284         if (status != AE_OK)
285                 context->ret.pointer = NULL;
286         return status;
287 }
288 EXPORT_SYMBOL(acpi_run_osc);
289
290 bool osc_sb_apei_support_acked;
291 static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
292 static void acpi_bus_osc_support(void)
293 {
294         u32 capbuf[2];
295         struct acpi_osc_context context = {
296                 .uuid_str = sb_uuid_str,
297                 .rev = 1,
298                 .cap.length = 8,
299                 .cap.pointer = capbuf,
300         };
301         acpi_handle handle;
302
303         capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
304         capbuf[OSC_SUPPORT_DWORD] = OSC_SB_PR3_SUPPORT; /* _PR3 is in use */
305 #if defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR) ||\
306                         defined(CONFIG_ACPI_PROCESSOR_AGGREGATOR_MODULE)
307         capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PAD_SUPPORT;
308 #endif
309
310 #if defined(CONFIG_ACPI_PROCESSOR) || defined(CONFIG_ACPI_PROCESSOR_MODULE)
311         capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PPC_OST_SUPPORT;
312 #endif
313
314         capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_HOTPLUG_OST_SUPPORT;
315
316         if (!ghes_disable)
317                 capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_APEI_SUPPORT;
318         if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
319                 return;
320         if (ACPI_SUCCESS(acpi_run_osc(handle, &context))) {
321                 u32 *capbuf_ret = context.ret.pointer;
322                 if (context.ret.length > OSC_SUPPORT_DWORD)
323                         osc_sb_apei_support_acked =
324                                 capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
325                 kfree(context.ret.pointer);
326         }
327         /* do we need to check other returned cap? Sounds no */
328 }
329
330 /* --------------------------------------------------------------------------
331                              Notification Handling
332    -------------------------------------------------------------------------- */
333
334 /**
335  * acpi_bus_notify
336  * ---------------
337  * Callback for all 'system-level' device notifications (values 0x00-0x7F).
338  */
339 static void acpi_bus_notify(acpi_handle handle, u32 type, void *data)
340 {
341         struct acpi_device *adev;
342         struct acpi_driver *driver;
343         acpi_status status;
344         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
345
346         switch (type) {
347         case ACPI_NOTIFY_BUS_CHECK:
348                 acpi_handle_debug(handle, "ACPI_NOTIFY_BUS_CHECK event\n");
349                 break;
350
351         case ACPI_NOTIFY_DEVICE_CHECK:
352                 acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK event\n");
353                 break;
354
355         case ACPI_NOTIFY_DEVICE_WAKE:
356                 acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_WAKE event\n");
357                 break;
358
359         case ACPI_NOTIFY_EJECT_REQUEST:
360                 acpi_handle_debug(handle, "ACPI_NOTIFY_EJECT_REQUEST event\n");
361                 break;
362
363         case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
364                 acpi_handle_debug(handle, "ACPI_NOTIFY_DEVICE_CHECK_LIGHT event\n");
365                 /* TBD: Exactly what does 'light' mean? */
366                 break;
367
368         case ACPI_NOTIFY_FREQUENCY_MISMATCH:
369                 acpi_handle_err(handle, "Device cannot be configured due "
370                                 "to a frequency mismatch\n");
371                 break;
372
373         case ACPI_NOTIFY_BUS_MODE_MISMATCH:
374                 acpi_handle_err(handle, "Device cannot be configured due "
375                                 "to a bus mode mismatch\n");
376                 break;
377
378         case ACPI_NOTIFY_POWER_FAULT:
379                 acpi_handle_err(handle, "Device has suffered a power fault\n");
380                 break;
381
382         default:
383                 acpi_handle_debug(handle, "Unknown event type 0x%x\n", type);
384                 break;
385         }
386
387         adev = acpi_bus_get_acpi_device(handle);
388         if (!adev)
389                 goto err;
390
391         driver = adev->driver;
392         if (driver && driver->ops.notify &&
393             (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
394                 driver->ops.notify(adev, type);
395
396         switch (type) {
397         case ACPI_NOTIFY_BUS_CHECK:
398         case ACPI_NOTIFY_DEVICE_CHECK:
399         case ACPI_NOTIFY_EJECT_REQUEST:
400                 status = acpi_hotplug_schedule(adev, type);
401                 if (ACPI_SUCCESS(status))
402                         return;
403         default:
404                 break;
405         }
406         acpi_bus_put_acpi_device(adev);
407         return;
408
409  err:
410         acpi_evaluate_ost(handle, type, ost_code, NULL);
411 }
412
413 /* --------------------------------------------------------------------------
414                              Initialization/Cleanup
415    -------------------------------------------------------------------------- */
416
417 static int __init acpi_bus_init_irq(void)
418 {
419         acpi_status status;
420         char *message = NULL;
421
422
423         /*
424          * Let the system know what interrupt model we are using by
425          * evaluating the \_PIC object, if exists.
426          */
427
428         switch (acpi_irq_model) {
429         case ACPI_IRQ_MODEL_PIC:
430                 message = "PIC";
431                 break;
432         case ACPI_IRQ_MODEL_IOAPIC:
433                 message = "IOAPIC";
434                 break;
435         case ACPI_IRQ_MODEL_IOSAPIC:
436                 message = "IOSAPIC";
437                 break;
438         case ACPI_IRQ_MODEL_PLATFORM:
439                 message = "platform specific model";
440                 break;
441         default:
442                 printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
443                 return -ENODEV;
444         }
445
446         printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
447
448         status = acpi_execute_simple_method(NULL, "\\_PIC", acpi_irq_model);
449         if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
450                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PIC"));
451                 return -ENODEV;
452         }
453
454         return 0;
455 }
456
457 u8 acpi_gbl_permanent_mmap;
458
459
460 void __init acpi_early_init(void)
461 {
462         acpi_status status;
463
464         if (acpi_disabled)
465                 return;
466
467         printk(KERN_INFO PREFIX "Core revision %08x\n", ACPI_CA_VERSION);
468
469         /* enable workarounds, unless strict ACPI spec. compliance */
470         if (!acpi_strict)
471                 acpi_gbl_enable_interpreter_slack = TRUE;
472
473         acpi_gbl_permanent_mmap = 1;
474
475         /*
476          * If the machine falls into the DMI check table,
477          * DSDT will be copied to memory
478          */
479         dmi_check_system(dsdt_dmi_table);
480
481         status = acpi_reallocate_root_table();
482         if (ACPI_FAILURE(status)) {
483                 printk(KERN_ERR PREFIX
484                        "Unable to reallocate ACPI tables\n");
485                 goto error0;
486         }
487
488         status = acpi_initialize_subsystem();
489         if (ACPI_FAILURE(status)) {
490                 printk(KERN_ERR PREFIX
491                        "Unable to initialize the ACPI Interpreter\n");
492                 goto error0;
493         }
494
495         status = acpi_load_tables();
496         if (ACPI_FAILURE(status)) {
497                 printk(KERN_ERR PREFIX
498                        "Unable to load the System Description Tables\n");
499                 goto error0;
500         }
501
502 #ifdef CONFIG_X86
503         if (!acpi_ioapic) {
504                 /* compatible (0) means level (3) */
505                 if (!(acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)) {
506                         acpi_sci_flags &= ~ACPI_MADT_TRIGGER_MASK;
507                         acpi_sci_flags |= ACPI_MADT_TRIGGER_LEVEL;
508                 }
509                 /* Set PIC-mode SCI trigger type */
510                 acpi_pic_sci_set_trigger(acpi_gbl_FADT.sci_interrupt,
511                                          (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
512         } else {
513                 /*
514                  * now that acpi_gbl_FADT is initialized,
515                  * update it with result from INT_SRC_OVR parsing
516                  */
517                 acpi_gbl_FADT.sci_interrupt = acpi_sci_override_gsi;
518         }
519 #endif
520
521         status = acpi_enable_subsystem(~ACPI_NO_ACPI_ENABLE);
522         if (ACPI_FAILURE(status)) {
523                 printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
524                 goto error0;
525         }
526
527         /*
528          * If the system is using ACPI then we can be reasonably
529          * confident that any regulators are managed by the firmware
530          * so tell the regulator core it has everything it needs to
531          * know.
532          */
533         regulator_has_full_constraints();
534
535         return;
536
537       error0:
538         disable_acpi();
539         return;
540 }
541
542 static int __init acpi_bus_init(void)
543 {
544         int result;
545         acpi_status status;
546
547         acpi_os_initialize1();
548
549         status = acpi_enable_subsystem(ACPI_NO_ACPI_ENABLE);
550         if (ACPI_FAILURE(status)) {
551                 printk(KERN_ERR PREFIX
552                        "Unable to start the ACPI Interpreter\n");
553                 goto error1;
554         }
555
556         /*
557          * ACPI 2.0 requires the EC driver to be loaded and work before
558          * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
559          * is called).
560          *
561          * This is accomplished by looking for the ECDT table, and getting
562          * the EC parameters out of that.
563          */
564         status = acpi_ec_ecdt_probe();
565         /* Ignore result. Not having an ECDT is not fatal. */
566
567         status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
568         if (ACPI_FAILURE(status)) {
569                 printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
570                 goto error1;
571         }
572
573         /*
574          * _OSC method may exist in module level code,
575          * so it must be run after ACPI_FULL_INITIALIZATION
576          */
577         acpi_bus_osc_support();
578
579         /*
580          * _PDC control method may load dynamic SSDT tables,
581          * and we need to install the table handler before that.
582          */
583         acpi_sysfs_init();
584
585         acpi_early_processor_set_pdc();
586
587         /*
588          * Maybe EC region is required at bus_scan/acpi_get_devices. So it
589          * is necessary to enable it as early as possible.
590          */
591         acpi_boot_ec_enable();
592
593         printk(KERN_INFO PREFIX "Interpreter enabled\n");
594
595         /* Initialize sleep structures */
596         acpi_sleep_init();
597
598         /*
599          * Get the system interrupt model and evaluate \_PIC.
600          */
601         result = acpi_bus_init_irq();
602         if (result)
603                 goto error1;
604
605         /*
606          * Register the for all standard device notifications.
607          */
608         status =
609             acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY,
610                                         &acpi_bus_notify, NULL);
611         if (ACPI_FAILURE(status)) {
612                 printk(KERN_ERR PREFIX
613                        "Unable to register for device notifications\n");
614                 goto error1;
615         }
616
617         /*
618          * Create the top ACPI proc directory
619          */
620         acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
621
622         return 0;
623
624         /* Mimic structured exception handling */
625       error1:
626         acpi_terminate();
627         return -ENODEV;
628 }
629
630 struct kobject *acpi_kobj;
631 EXPORT_SYMBOL_GPL(acpi_kobj);
632
633 static int __init acpi_init(void)
634 {
635         int result;
636
637         if (acpi_disabled) {
638                 printk(KERN_INFO PREFIX "Interpreter disabled.\n");
639                 return -ENODEV;
640         }
641
642         acpi_kobj = kobject_create_and_add("acpi", firmware_kobj);
643         if (!acpi_kobj) {
644                 printk(KERN_WARNING "%s: kset create error\n", __func__);
645                 acpi_kobj = NULL;
646         }
647
648         init_acpi_device_notify();
649         result = acpi_bus_init();
650         if (result) {
651                 disable_acpi();
652                 return result;
653         }
654
655         pci_mmcfg_late_init();
656         acpi_scan_init();
657         acpi_ec_init();
658         acpi_debugfs_init();
659         acpi_sleep_proc_init();
660         acpi_wakeup_device_init();
661         return 0;
662 }
663
664 subsys_initcall(acpi_init);