linux/drivers/acpi/scan.c
Linus Torvalds 58a0228707 ACPI updates for 4.20-rc1
- Fix ACPICA issues related to the handling of module-level AML
    and make the ACPI initialization code parse ECDT before loading
    the definition block tables (Erik Schmauss).
 
  - Update ACPICA to upstream revision 20181003 including fixes
    related to the ill-defined "generic serial bus" and the handling
    of the _REG object (Bob Moore).
 
  - Fix some issues with system-wide suspend/resume on Intel BYT/CHT
    related to the handling of I2C controllers in the ACPI LPSS driver
    for Intel SoCs (Hans de Goede).
 
  - Modify the ACPI namespace scanning code to enumerate INT33FE HID
    devices as platform devices with I2C resources to avoid device
    enumeration problems on boards with Dollar Cove or Whiskey Cove
    Intel PMICs (Hans de Goede).
 
  - Prevent ACPICA from using ktime_get() during early resume from
    system-wide suspend before resuming the timekeeping which generally
    is unsafe and triggers a warning from the timekeeping code (Bart
    Van Assche).
 
  - Add low-level real time clock support to the ACPI Time and Aalarm
    Device (TAD) driver (Rafael Wysocki).
 
  - Fix the ACPI SBS driver to avoid GPE storms on MacBook Pro and
    Oopses when removing modules (Ronald Tschalär).
 
  - Fix the ACPI PPTT parsing code to handle architecturally unknown
    cache types properly (Jeffrey Hugo).
 
  - Fix initialization issue in the ACPI processor driver (Dou Liyang).
 
  - Clean up the code in several places (Andy Shevchenko, Bartlomiej
    Zolnierkiewicz, David Arcari, zhong jiang).
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJbya1ZAAoJEILEb/54YlRxGxwQAKLDDN3lDvSJqKrFiFbgpvCz
 f8hSmVmWvHqJwiKmP0OllVvk31xr4BIf5BxdxMVSK/+OFAEv3WBv3ajZl5y4gxPx
 g+3u8fiBCX4OX2iQX5B4cfaEGrZfUk87S7yW3H/pfgDphQ4SqsEvKMhxB9LveHjL
 YZW4kEjQZskNL/17wbAyI2XG3udQhzbSMVezk4xzByly9b0TcRSdbx6qKjh5rmEK
 658nZxc7EM2JyCsGIunJhKuXvcsR2SrHbTpk8h0GW54NBuDkF5nRmsVI8MbdDRpi
 cnW62robM6rso2ev/sYFE1OQkm7tf8MLc558MTeib35NPa9ass7rPdfroxYLUv/r
 x3Jo7WzHLhGnDhPXdRCFTVuc5fp0huEM35JXhjmbTJtcugaDYrYnp6pxtaMG2CPi
 XzPGe4lK7QlW5ojCJ0fnpbOKqhryI4kPZHmZNLYiC0dOwKBTHnS7DWNlIxazMnaK
 iUxZjeF+mu5qIiL/+s618KgKNyRZNjbhTZZ637SOPeyxbDSKHs1Mm1Fu24+UPUVF
 9XWhPPHPDSKF7fGeJJbxdUF+FAbu3sJJBDZdvD41e642qCVy662dvog5PdVITrgt
 iB6Y/UHgpsHhxCT7NtPuIVLNvMxfMdZwnUlncmVqQg/VaRfGZ8STU9wrhcok1WU3
 l/9QhTkXxg0vPhcLAvCF
 =arbR
 -----END PGP SIGNATURE-----

Merge tag 'acpi-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "These fix ACPICA issues related to the handling of module-level AML,
  fix an ordering issue during ACPI initialization, update ACPICA to
  upstream revision 20181003 (including fixes mostly), fix issues with
  system-wide suspend/resume related to the ACPI driver for Intel SoCs
  (LPSS), fix device enumeration issues on boards with Dollar Cove or
  Whiskey Cove Intel PMICs, prevent ACPICA from calling ktime_get() in
  unsuitable conditions, update a few drivers and clean up some code in
  several places.

  Specifics:

   - Fix ACPICA issues related to the handling of module-level AML and
     make the ACPI initialization code parse ECDT before loading the
     definition block tables (Erik Schmauss).

   - Update ACPICA to upstream revision 20181003 including fixes related
     to the ill-defined "generic serial bus" and the handling of the
     _REG object (Bob Moore).

   - Fix some issues with system-wide suspend/resume on Intel BYT/CHT
     related to the handling of I2C controllers in the ACPI LPSS driver
     for Intel SoCs (Hans de Goede).

   - Modify the ACPI namespace scanning code to enumerate INT33FE HID
     devices as platform devices with I2C resources to avoid device
     enumeration problems on boards with Dollar Cove or Whiskey Cove
     Intel PMICs (Hans de Goede).

   - Prevent ACPICA from using ktime_get() during early resume from
     system-wide suspend before resuming the timekeeping which generally
     is unsafe and triggers a warning from the timekeeping code (Bart
     Van Assche).

   - Add low-level real time clock support to the ACPI Time and Aalarm
     Device (TAD) driver (Rafael Wysocki).

   - Fix the ACPI SBS driver to avoid GPE storms on MacBook Pro and
     Oopses when removing modules (Ronald Tschalär).

   - Fix the ACPI PPTT parsing code to handle architecturally unknown
     cache types properly (Jeffrey Hugo).

   - Fix initialization issue in the ACPI processor driver (Dou Liyang).

   - Clean up the code in several places (Andy Shevchenko, Bartlomiej
     Zolnierkiewicz, David Arcari, zhong jiang)"

* tag 'acpi-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (33 commits)
  ACPI / scan: Create platform device for INT33FE ACPI nodes
  ACPI / OSL: Use 'jiffies' as the time bassis for acpi_os_get_timer()
  ACPI: probe ECDT before loading AML tables regardless of module-level code flag
  ACPICA: Remove acpi_gbl_group_module_level_code and only use acpi_gbl_execute_tables_as_methods instead
  ACPICA: AML Parser: fix parse loop to correctly skip erroneous extended opcodes
  ACPICA: AML interpreter: add region addresses in global list during initialization
  ACPI: TAD: Add low-level support for real time capability
  ACPI: remove redundant 'default n' from Kconfig
  ACPI / SBS: Fix rare oops when removing modules
  ACPI / SBS: Fix GPE storm on recent MacBookPro's
  ACPI/PPTT: Handle architecturally unknown cache types
  drivers: base: cacheinfo: Do not populate sysfs for unknown cache types
  ACPICA: Update version to 20181003
  ACPICA: Never run _REG on system_memory and system_IO
  ACPICA: Split large interpreter file
  ACPICA: Update for field unit access
  ACPICA: Rename some of the Field Attribute defines
  ACPICA: Update for generic_serial_bus and attrib_raw_process_bytes protocol
  ACPI / processor: Fix the return value of acpi_processor_ids_walk()
  ACPI / LPSS: Resume BYT/CHT I2C controllers from resume_noirq
  ...
2018-10-23 10:33:16 +01:00

2325 lines
58 KiB
C

/*
* scan.c - support for transforming the ACPI namespace into individual objects
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/acpi.h>
#include <linux/acpi_iort.h>
#include <linux/signal.h>
#include <linux/kthread.h>
#include <linux/dmi.h>
#include <linux/nls.h>
#include <linux/dma-mapping.h>
#include <linux/platform_data/x86/apple.h>
#include <asm/pgtable.h>
#include "internal.h"
#define _COMPONENT ACPI_BUS_COMPONENT
ACPI_MODULE_NAME("scan");
extern struct acpi_device *acpi_root;
#define ACPI_BUS_CLASS "system_bus"
#define ACPI_BUS_HID "LNXSYBUS"
#define ACPI_BUS_DEVICE_NAME "System Bus"
#define ACPI_IS_ROOT_DEVICE(device) (!(device)->parent)
#define INVALID_ACPI_HANDLE ((acpi_handle)empty_zero_page)
static const char *dummy_hid = "device";
static LIST_HEAD(acpi_dep_list);
static DEFINE_MUTEX(acpi_dep_list_lock);
LIST_HEAD(acpi_bus_id_list);
static DEFINE_MUTEX(acpi_scan_lock);
static LIST_HEAD(acpi_scan_handlers_list);
DEFINE_MUTEX(acpi_device_lock);
LIST_HEAD(acpi_wakeup_device_list);
static DEFINE_MUTEX(acpi_hp_context_lock);
/*
* The UART device described by the SPCR table is the only object which needs
* special-casing. Everything else is covered by ACPI namespace paths in STAO
* table.
*/
static u64 spcr_uart_addr;
struct acpi_dep_data {
struct list_head node;
acpi_handle master;
acpi_handle slave;
};
void acpi_scan_lock_acquire(void)
{
mutex_lock(&acpi_scan_lock);
}
EXPORT_SYMBOL_GPL(acpi_scan_lock_acquire);
void acpi_scan_lock_release(void)
{
mutex_unlock(&acpi_scan_lock);
}
EXPORT_SYMBOL_GPL(acpi_scan_lock_release);
void acpi_lock_hp_context(void)
{
mutex_lock(&acpi_hp_context_lock);
}
void acpi_unlock_hp_context(void)
{
mutex_unlock(&acpi_hp_context_lock);
}
void acpi_initialize_hp_context(struct acpi_device *adev,
struct acpi_hotplug_context *hp,
int (*notify)(struct acpi_device *, u32),
void (*uevent)(struct acpi_device *, u32))
{
acpi_lock_hp_context();
hp->notify = notify;
hp->uevent = uevent;
acpi_set_hp_context(adev, hp);
acpi_unlock_hp_context();
}
EXPORT_SYMBOL_GPL(acpi_initialize_hp_context);
int acpi_scan_add_handler(struct acpi_scan_handler *handler)
{
if (!handler)
return -EINVAL;
list_add_tail(&handler->list_node, &acpi_scan_handlers_list);
return 0;
}
int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler,
const char *hotplug_profile_name)
{
int error;
error = acpi_scan_add_handler(handler);
if (error)
return error;
acpi_sysfs_add_hotplug_profile(&handler->hotplug, hotplug_profile_name);
return 0;
}
bool acpi_scan_is_offline(struct acpi_device *adev, bool uevent)
{
struct acpi_device_physical_node *pn;
bool offline = true;
char *envp[] = { "EVENT=offline", NULL };
/*
* acpi_container_offline() calls this for all of the container's
* children under the container's physical_node_lock lock.
*/
mutex_lock_nested(&adev->physical_node_lock, SINGLE_DEPTH_NESTING);
list_for_each_entry(pn, &adev->physical_node_list, node)
if (device_supports_offline(pn->dev) && !pn->dev->offline) {
if (uevent)
kobject_uevent_env(&pn->dev->kobj, KOBJ_CHANGE, envp);
offline = false;
break;
}
mutex_unlock(&adev->physical_node_lock);
return offline;
}
static acpi_status acpi_bus_offline(acpi_handle handle, u32 lvl, void *data,
void **ret_p)
{
struct acpi_device *device = NULL;
struct acpi_device_physical_node *pn;
bool second_pass = (bool)data;
acpi_status status = AE_OK;
if (acpi_bus_get_device(handle, &device))
return AE_OK;
if (device->handler && !device->handler->hotplug.enabled) {
*ret_p = &device->dev;
return AE_SUPPORT;
}
mutex_lock(&device->physical_node_lock);
list_for_each_entry(pn, &device->physical_node_list, node) {
int ret;
if (second_pass) {
/* Skip devices offlined by the first pass. */
if (pn->put_online)
continue;
} else {
pn->put_online = false;
}
ret = device_offline(pn->dev);
if (ret >= 0) {
pn->put_online = !ret;
} else {
*ret_p = pn->dev;
if (second_pass) {
status = AE_ERROR;
break;
}
}
}
mutex_unlock(&device->physical_node_lock);
return status;
}
static acpi_status acpi_bus_online(acpi_handle handle, u32 lvl, void *data,
void **ret_p)
{
struct acpi_device *device = NULL;
struct acpi_device_physical_node *pn;
if (acpi_bus_get_device(handle, &device))
return AE_OK;
mutex_lock(&device->physical_node_lock);
list_for_each_entry(pn, &device->physical_node_list, node)
if (pn->put_online) {
device_online(pn->dev);
pn->put_online = false;
}
mutex_unlock(&device->physical_node_lock);
return AE_OK;
}
static int acpi_scan_try_to_offline(struct acpi_device *device)
{
acpi_handle handle = device->handle;
struct device *errdev = NULL;
acpi_status status;
/*
* Carry out two passes here and ignore errors in the first pass,
* because if the devices in question are memory blocks and
* CONFIG_MEMCG is set, one of the blocks may hold data structures
* that the other blocks depend on, but it is not known in advance which
* block holds them.
*
* If the first pass is successful, the second one isn't needed, though.
*/
status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
NULL, acpi_bus_offline, (void *)false,
(void **)&errdev);
if (status == AE_SUPPORT) {
dev_warn(errdev, "Offline disabled.\n");
acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
acpi_bus_online, NULL, NULL, NULL);
return -EPERM;
}
acpi_bus_offline(handle, 0, (void *)false, (void **)&errdev);
if (errdev) {
errdev = NULL;
acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
NULL, acpi_bus_offline, (void *)true,
(void **)&errdev);
if (!errdev)
acpi_bus_offline(handle, 0, (void *)true,
(void **)&errdev);
if (errdev) {
dev_warn(errdev, "Offline failed.\n");
acpi_bus_online(handle, 0, NULL, NULL);
acpi_walk_namespace(ACPI_TYPE_ANY, handle,
ACPI_UINT32_MAX, acpi_bus_online,
NULL, NULL, NULL);
return -EBUSY;
}
}
return 0;
}
static int acpi_scan_hot_remove(struct acpi_device *device)
{
acpi_handle handle = device->handle;
unsigned long long sta;
acpi_status status;
if (device->handler && device->handler->hotplug.demand_offline) {
if (!acpi_scan_is_offline(device, true))
return -EBUSY;
} else {
int error = acpi_scan_try_to_offline(device);
if (error)
return error;
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Hot-removing device %s...\n", dev_name(&device->dev)));
acpi_bus_trim(device);
acpi_evaluate_lck(handle, 0);
/*
* TBD: _EJD support.
*/
status = acpi_evaluate_ej0(handle);
if (status == AE_NOT_FOUND)
return -ENODEV;
else if (ACPI_FAILURE(status))
return -EIO;
/*
* Verify if eject was indeed successful. If not, log an error
* message. No need to call _OST since _EJ0 call was made OK.
*/
status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
if (ACPI_FAILURE(status)) {
acpi_handle_warn(handle,
"Status check after eject failed (0x%x)\n", status);
} else if (sta & ACPI_STA_DEVICE_ENABLED) {
acpi_handle_warn(handle,
"Eject incomplete - status 0x%llx\n", sta);
}
return 0;
}
static int acpi_scan_device_not_present(struct acpi_device *adev)
{
if (!acpi_device_enumerated(adev)) {
dev_warn(&adev->dev, "Still not present\n");
return -EALREADY;
}
acpi_bus_trim(adev);
return 0;
}
static int acpi_scan_device_check(struct acpi_device *adev)
{
int error;
acpi_bus_get_status(adev);
if (adev->status.present || adev->status.functional) {
/*
* This function is only called for device objects for which
* matching scan handlers exist. The only situation in which
* the scan handler is not attached to this device object yet
* is when the device has just appeared (either it wasn't
* present at all before or it was removed and then added
* again).
*/
if (adev->handler) {
dev_warn(&adev->dev, "Already enumerated\n");
return -EALREADY;
}
error = acpi_bus_scan(adev->handle);
if (error) {
dev_warn(&adev->dev, "Namespace scan failure\n");
return error;
}
if (!adev->handler) {
dev_warn(&adev->dev, "Enumeration failure\n");
error = -ENODEV;
}
} else {
error = acpi_scan_device_not_present(adev);
}
return error;
}
static int acpi_scan_bus_check(struct acpi_device *adev)
{
struct acpi_scan_handler *handler = adev->handler;
struct acpi_device *child;
int error;
acpi_bus_get_status(adev);
if (!(adev->status.present || adev->status.functional)) {
acpi_scan_device_not_present(adev);
return 0;
}
if (handler && handler->hotplug.scan_dependent)
return handler->hotplug.scan_dependent(adev);
error = acpi_bus_scan(adev->handle);
if (error) {
dev_warn(&adev->dev, "Namespace scan failure\n");
return error;
}
list_for_each_entry(child, &adev->children, node) {
error = acpi_scan_bus_check(child);
if (error)
return error;
}
return 0;
}
static int acpi_generic_hotplug_event(struct acpi_device *adev, u32 type)
{
switch (type) {
case ACPI_NOTIFY_BUS_CHECK:
return acpi_scan_bus_check(adev);
case ACPI_NOTIFY_DEVICE_CHECK:
return acpi_scan_device_check(adev);
case ACPI_NOTIFY_EJECT_REQUEST:
case ACPI_OST_EC_OSPM_EJECT:
if (adev->handler && !adev->handler->hotplug.enabled) {
dev_info(&adev->dev, "Eject disabled\n");
return -EPERM;
}
acpi_evaluate_ost(adev->handle, ACPI_NOTIFY_EJECT_REQUEST,
ACPI_OST_SC_EJECT_IN_PROGRESS, NULL);
return acpi_scan_hot_remove(adev);
}
return -EINVAL;
}
void acpi_device_hotplug(struct acpi_device *adev, u32 src)
{
u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
int error = -ENODEV;
lock_device_hotplug();
mutex_lock(&acpi_scan_lock);
/*
* The device object's ACPI handle cannot become invalid as long as we
* are holding acpi_scan_lock, but it might have become invalid before
* that lock was acquired.
*/
if (adev->handle == INVALID_ACPI_HANDLE)
goto err_out;
if (adev->flags.is_dock_station) {
error = dock_notify(adev, src);
} else if (adev->flags.hotplug_notify) {
error = acpi_generic_hotplug_event(adev, src);
} else {
int (*notify)(struct acpi_device *, u32);
acpi_lock_hp_context();
notify = adev->hp ? adev->hp->notify : NULL;
acpi_unlock_hp_context();
/*
* There may be additional notify handlers for device objects
* without the .event() callback, so ignore them here.
*/
if (notify)
error = notify(adev, src);
else
goto out;
}
switch (error) {
case 0:
ost_code = ACPI_OST_SC_SUCCESS;
break;
case -EPERM:
ost_code = ACPI_OST_SC_EJECT_NOT_SUPPORTED;
break;
case -EBUSY:
ost_code = ACPI_OST_SC_DEVICE_BUSY;
break;
default:
ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
break;
}
err_out:
acpi_evaluate_ost(adev->handle, src, ost_code, NULL);
out:
acpi_bus_put_acpi_device(adev);
mutex_unlock(&acpi_scan_lock);
unlock_device_hotplug();
}
static void acpi_free_power_resources_lists(struct acpi_device *device)
{
int i;
if (device->wakeup.flags.valid)
acpi_power_resources_list_free(&device->wakeup.resources);
if (!device->power.flags.power_resources)
return;
for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
struct acpi_device_power_state *ps = &device->power.states[i];
acpi_power_resources_list_free(&ps->resources);
}
}
static void acpi_device_release(struct device *dev)
{
struct acpi_device *acpi_dev = to_acpi_device(dev);
acpi_free_properties(acpi_dev);
acpi_free_pnp_ids(&acpi_dev->pnp);
acpi_free_power_resources_lists(acpi_dev);
kfree(acpi_dev);
}
static void acpi_device_del(struct acpi_device *device)
{
struct acpi_device_bus_id *acpi_device_bus_id;
mutex_lock(&acpi_device_lock);
if (device->parent)
list_del(&device->node);
list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
if (!strcmp(acpi_device_bus_id->bus_id,
acpi_device_hid(device))) {
if (acpi_device_bus_id->instance_no > 0)
acpi_device_bus_id->instance_no--;
else {
list_del(&acpi_device_bus_id->node);
kfree(acpi_device_bus_id);
}
break;
}
list_del(&device->wakeup_list);
mutex_unlock(&acpi_device_lock);
acpi_power_add_remove_device(device, false);
acpi_device_remove_files(device);
if (device->remove)
device->remove(device);
device_del(&device->dev);
}
static BLOCKING_NOTIFIER_HEAD(acpi_reconfig_chain);
static LIST_HEAD(acpi_device_del_list);
static DEFINE_MUTEX(acpi_device_del_lock);
static void acpi_device_del_work_fn(struct work_struct *work_not_used)
{
for (;;) {
struct acpi_device *adev;
mutex_lock(&acpi_device_del_lock);
if (list_empty(&acpi_device_del_list)) {
mutex_unlock(&acpi_device_del_lock);
break;
}
adev = list_first_entry(&acpi_device_del_list,
struct acpi_device, del_list);
list_del(&adev->del_list);
mutex_unlock(&acpi_device_del_lock);
blocking_notifier_call_chain(&acpi_reconfig_chain,
ACPI_RECONFIG_DEVICE_REMOVE, adev);
acpi_device_del(adev);
/*
* Drop references to all power resources that might have been
* used by the device.
*/
acpi_power_transition(adev, ACPI_STATE_D3_COLD);
put_device(&adev->dev);
}
}
/**
* acpi_scan_drop_device - Drop an ACPI device object.
* @handle: Handle of an ACPI namespace node, not used.
* @context: Address of the ACPI device object to drop.
*
* This is invoked by acpi_ns_delete_node() during the removal of the ACPI
* namespace node the device object pointed to by @context is attached to.
*
* The unregistration is carried out asynchronously to avoid running
* acpi_device_del() under the ACPICA's namespace mutex and the list is used to
* ensure the correct ordering (the device objects must be unregistered in the
* same order in which the corresponding namespace nodes are deleted).
*/
static void acpi_scan_drop_device(acpi_handle handle, void *context)
{
static DECLARE_WORK(work, acpi_device_del_work_fn);
struct acpi_device *adev = context;
mutex_lock(&acpi_device_del_lock);
/*
* Use the ACPI hotplug workqueue which is ordered, so this work item
* won't run after any hotplug work items submitted subsequently. That
* prevents attempts to register device objects identical to those being
* deleted from happening concurrently (such attempts result from
* hotplug events handled via the ACPI hotplug workqueue). It also will
* run after all of the work items submitted previosuly, which helps
* those work items to ensure that they are not accessing stale device
* objects.
*/
if (list_empty(&acpi_device_del_list))
acpi_queue_hotplug_work(&work);
list_add_tail(&adev->del_list, &acpi_device_del_list);
/* Make acpi_ns_validate_handle() return NULL for this handle. */
adev->handle = INVALID_ACPI_HANDLE;
mutex_unlock(&acpi_device_del_lock);
}
static int acpi_get_device_data(acpi_handle handle, struct acpi_device **device,
void (*callback)(void *))
{
acpi_status status;
if (!device)
return -EINVAL;
status = acpi_get_data_full(handle, acpi_scan_drop_device,
(void **)device, callback);
if (ACPI_FAILURE(status) || !*device) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No context for object [%p]\n",
handle));
return -ENODEV;
}
return 0;
}
int acpi_bus_get_device(acpi_handle handle, struct acpi_device **device)
{
return acpi_get_device_data(handle, device, NULL);
}
EXPORT_SYMBOL(acpi_bus_get_device);
static void get_acpi_device(void *dev)
{
if (dev)
get_device(&((struct acpi_device *)dev)->dev);
}
struct acpi_device *acpi_bus_get_acpi_device(acpi_handle handle)
{
struct acpi_device *adev = NULL;
acpi_get_device_data(handle, &adev, get_acpi_device);
return adev;
}
void acpi_bus_put_acpi_device(struct acpi_device *adev)
{
put_device(&adev->dev);
}
int acpi_device_add(struct acpi_device *device,
void (*release)(struct device *))
{
int result;
struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
int found = 0;
if (device->handle) {
acpi_status status;
status = acpi_attach_data(device->handle, acpi_scan_drop_device,
device);
if (ACPI_FAILURE(status)) {
acpi_handle_err(device->handle,
"Unable to attach device data\n");
return -ENODEV;
}
}
/*
* Linkage
* -------
* Link this device to its parent and siblings.
*/
INIT_LIST_HEAD(&device->children);
INIT_LIST_HEAD(&device->node);
INIT_LIST_HEAD(&device->wakeup_list);
INIT_LIST_HEAD(&device->physical_node_list);
INIT_LIST_HEAD(&device->del_list);
mutex_init(&device->physical_node_lock);
new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
if (!new_bus_id) {
pr_err(PREFIX "Memory allocation error\n");
result = -ENOMEM;
goto err_detach;
}
mutex_lock(&acpi_device_lock);
/*
* Find suitable bus_id and instance number in acpi_bus_id_list
* If failed, create one and link it into acpi_bus_id_list
*/
list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
if (!strcmp(acpi_device_bus_id->bus_id,
acpi_device_hid(device))) {
acpi_device_bus_id->instance_no++;
found = 1;
kfree(new_bus_id);
break;
}
}
if (!found) {
acpi_device_bus_id = new_bus_id;
strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
acpi_device_bus_id->instance_no = 0;
list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
}
dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
if (device->parent)
list_add_tail(&device->node, &device->parent->children);
if (device->wakeup.flags.valid)
list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
mutex_unlock(&acpi_device_lock);
if (device->parent)
device->dev.parent = &device->parent->dev;
device->dev.bus = &acpi_bus_type;
device->dev.release = release;
result = device_add(&device->dev);
if (result) {
dev_err(&device->dev, "Error registering device\n");
goto err;
}
result = acpi_device_setup_files(device);
if (result)
printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
dev_name(&device->dev));
return 0;
err:
mutex_lock(&acpi_device_lock);
if (device->parent)
list_del(&device->node);
list_del(&device->wakeup_list);
mutex_unlock(&acpi_device_lock);
err_detach:
acpi_detach_data(device->handle, acpi_scan_drop_device);
return result;
}
/* --------------------------------------------------------------------------
Device Enumeration
-------------------------------------------------------------------------- */
static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
{
struct acpi_device *device = NULL;
acpi_status status;
/*
* Fixed hardware devices do not appear in the namespace and do not
* have handles, but we fabricate acpi_devices for them, so we have
* to deal with them specially.
*/
if (!handle)
return acpi_root;
do {
status = acpi_get_parent(handle, &handle);
if (ACPI_FAILURE(status))
return status == AE_NULL_ENTRY ? NULL : acpi_root;
} while (acpi_bus_get_device(handle, &device));
return device;
}
acpi_status
acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
{
acpi_status status;
acpi_handle tmp;
struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
union acpi_object *obj;
status = acpi_get_handle(handle, "_EJD", &tmp);
if (ACPI_FAILURE(status))
return status;
status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
if (ACPI_SUCCESS(status)) {
obj = buffer.pointer;
status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
ejd);
kfree(buffer.pointer);
}
return status;
}
EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
static int acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
struct acpi_device_wakeup *wakeup)
{
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *package = NULL;
union acpi_object *element = NULL;
acpi_status status;
int err = -ENODATA;
if (!wakeup)
return -EINVAL;
INIT_LIST_HEAD(&wakeup->resources);
/* _PRW */
status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
return err;
}
package = (union acpi_object *)buffer.pointer;
if (!package || package->package.count < 2)
goto out;
element = &(package->package.elements[0]);
if (!element)
goto out;
if (element->type == ACPI_TYPE_PACKAGE) {
if ((element->package.count < 2) ||
(element->package.elements[0].type !=
ACPI_TYPE_LOCAL_REFERENCE)
|| (element->package.elements[1].type != ACPI_TYPE_INTEGER))
goto out;
wakeup->gpe_device =
element->package.elements[0].reference.handle;
wakeup->gpe_number =
(u32) element->package.elements[1].integer.value;
} else if (element->type == ACPI_TYPE_INTEGER) {
wakeup->gpe_device = NULL;
wakeup->gpe_number = element->integer.value;
} else {
goto out;
}
element = &(package->package.elements[1]);
if (element->type != ACPI_TYPE_INTEGER)
goto out;
wakeup->sleep_state = element->integer.value;
err = acpi_extract_power_resources(package, 2, &wakeup->resources);
if (err)
goto out;
if (!list_empty(&wakeup->resources)) {
int sleep_state;
err = acpi_power_wakeup_list_init(&wakeup->resources,
&sleep_state);
if (err) {
acpi_handle_warn(handle, "Retrieving current states "
"of wakeup power resources failed\n");
acpi_power_resources_list_free(&wakeup->resources);
goto out;
}
if (sleep_state < wakeup->sleep_state) {
acpi_handle_warn(handle, "Overriding _PRW sleep state "
"(S%d) by S%d from power resources\n",
(int)wakeup->sleep_state, sleep_state);
wakeup->sleep_state = sleep_state;
}
}
out:
kfree(buffer.pointer);
return err;
}
static bool acpi_wakeup_gpe_init(struct acpi_device *device)
{
static const struct acpi_device_id button_device_ids[] = {
{"PNP0C0C", 0},
{"PNP0C0D", 0},
{"PNP0C0E", 0},
{"", 0},
};
struct acpi_device_wakeup *wakeup = &device->wakeup;
acpi_status status;
wakeup->flags.notifier_present = 0;
/* Power button, Lid switch always enable wakeup */
if (!acpi_match_device_ids(device, button_device_ids)) {
if (!acpi_match_device_ids(device, &button_device_ids[1])) {
/* Do not use Lid/sleep button for S5 wakeup */
if (wakeup->sleep_state == ACPI_STATE_S5)
wakeup->sleep_state = ACPI_STATE_S4;
}
acpi_mark_gpe_for_wake(wakeup->gpe_device, wakeup->gpe_number);
device_set_wakeup_capable(&device->dev, true);
return true;
}
status = acpi_setup_gpe_for_wake(device->handle, wakeup->gpe_device,
wakeup->gpe_number);
return ACPI_SUCCESS(status);
}
static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
{
int err;
/* Presence of _PRW indicates wake capable */
if (!acpi_has_method(device->handle, "_PRW"))
return;
err = acpi_bus_extract_wakeup_device_power_package(device->handle,
&device->wakeup);
if (err) {
dev_err(&device->dev, "_PRW evaluation error: %d\n", err);
return;
}
device->wakeup.flags.valid = acpi_wakeup_gpe_init(device);
device->wakeup.prepare_count = 0;
/*
* Call _PSW/_DSW object to disable its ability to wake the sleeping
* system for the ACPI device with the _PRW object.
* The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
* So it is necessary to call _DSW object first. Only when it is not
* present will the _PSW object used.
*/
err = acpi_device_sleep_wake(device, 0, 0, 0);
if (err)
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"error in _DSW or _PSW evaluation\n"));
}
static void acpi_bus_init_power_state(struct acpi_device *device, int state)
{
struct acpi_device_power_state *ps = &device->power.states[state];
char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
acpi_status status;
INIT_LIST_HEAD(&ps->resources);
/* Evaluate "_PRx" to get referenced power resources */
status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
if (ACPI_SUCCESS(status)) {
union acpi_object *package = buffer.pointer;
if (buffer.length && package
&& package->type == ACPI_TYPE_PACKAGE
&& package->package.count) {
int err = acpi_extract_power_resources(package, 0,
&ps->resources);
if (!err)
device->power.flags.power_resources = 1;
}
ACPI_FREE(buffer.pointer);
}
/* Evaluate "_PSx" to see if we can do explicit sets */
pathname[2] = 'S';
if (acpi_has_method(device->handle, pathname))
ps->flags.explicit_set = 1;
/* State is valid if there are means to put the device into it. */
if (!list_empty(&ps->resources) || ps->flags.explicit_set)
ps->flags.valid = 1;
ps->power = -1; /* Unknown - driver assigned */
ps->latency = -1; /* Unknown - driver assigned */
}
static void acpi_bus_get_power_flags(struct acpi_device *device)
{
u32 i;
/* Presence of _PS0|_PR0 indicates 'power manageable' */
if (!acpi_has_method(device->handle, "_PS0") &&
!acpi_has_method(device->handle, "_PR0"))
return;
device->flags.power_manageable = 1;
/*
* Power Management Flags
*/
if (acpi_has_method(device->handle, "_PSC"))
device->power.flags.explicit_get = 1;
if (acpi_has_method(device->handle, "_IRC"))
device->power.flags.inrush_current = 1;
if (acpi_has_method(device->handle, "_DSW"))
device->power.flags.dsw_present = 1;
/*
* Enumerate supported power management states
*/
for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++)
acpi_bus_init_power_state(device, i);
INIT_LIST_HEAD(&device->power.states[ACPI_STATE_D3_COLD].resources);
if (!list_empty(&device->power.states[ACPI_STATE_D3_HOT].resources))
device->power.states[ACPI_STATE_D3_COLD].flags.valid = 1;
/* Set defaults for D0 and D3hot states (always valid) */
device->power.states[ACPI_STATE_D0].flags.valid = 1;
device->power.states[ACPI_STATE_D0].power = 100;
device->power.states[ACPI_STATE_D3_HOT].flags.valid = 1;
if (acpi_bus_init_power(device))
device->flags.power_manageable = 0;
}
static void acpi_bus_get_flags(struct acpi_device *device)
{
/* Presence of _STA indicates 'dynamic_status' */
if (acpi_has_method(device->handle, "_STA"))
device->flags.dynamic_status = 1;
/* Presence of _RMV indicates 'removable' */
if (acpi_has_method(device->handle, "_RMV"))
device->flags.removable = 1;
/* Presence of _EJD|_EJ0 indicates 'ejectable' */
if (acpi_has_method(device->handle, "_EJD") ||
acpi_has_method(device->handle, "_EJ0"))
device->flags.ejectable = 1;
}
static void acpi_device_get_busid(struct acpi_device *device)
{
char bus_id[5] = { '?', 0 };
struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
int i = 0;
/*
* Bus ID
* ------
* The device's Bus ID is simply the object name.
* TBD: Shouldn't this value be unique (within the ACPI namespace)?
*/
if (ACPI_IS_ROOT_DEVICE(device)) {
strcpy(device->pnp.bus_id, "ACPI");
return;
}
switch (device->device_type) {
case ACPI_BUS_TYPE_POWER_BUTTON:
strcpy(device->pnp.bus_id, "PWRF");
break;
case ACPI_BUS_TYPE_SLEEP_BUTTON:
strcpy(device->pnp.bus_id, "SLPF");
break;
case ACPI_BUS_TYPE_ECDT_EC:
strcpy(device->pnp.bus_id, "ECDT");
break;
default:
acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
/* Clean up trailing underscores (if any) */
for (i = 3; i > 1; i--) {
if (bus_id[i] == '_')
bus_id[i] = '\0';
else
break;
}
strcpy(device->pnp.bus_id, bus_id);
break;
}
}
/*
* acpi_ata_match - see if an acpi object is an ATA device
*
* If an acpi object has one of the ACPI ATA methods defined,
* then we can safely call it an ATA device.
*/
bool acpi_ata_match(acpi_handle handle)
{
return acpi_has_method(handle, "_GTF") ||
acpi_has_method(handle, "_GTM") ||
acpi_has_method(handle, "_STM") ||
acpi_has_method(handle, "_SDD");
}
/*
* acpi_bay_match - see if an acpi object is an ejectable driver bay
*
* If an acpi object is ejectable and has one of the ACPI ATA methods defined,
* then we can safely call it an ejectable drive bay
*/
bool acpi_bay_match(acpi_handle handle)
{
acpi_handle phandle;
if (!acpi_has_method(handle, "_EJ0"))
return false;
if (acpi_ata_match(handle))
return true;
if (ACPI_FAILURE(acpi_get_parent(handle, &phandle)))
return false;
return acpi_ata_match(phandle);
}
bool acpi_device_is_battery(struct acpi_device *adev)
{
struct acpi_hardware_id *hwid;
list_for_each_entry(hwid, &adev->pnp.ids, list)
if (!strcmp("PNP0C0A", hwid->id))
return true;
return false;
}
static bool is_ejectable_bay(struct acpi_device *adev)
{
acpi_handle handle = adev->handle;
if (acpi_has_method(handle, "_EJ0") && acpi_device_is_battery(adev))
return true;
return acpi_bay_match(handle);
}
/*
* acpi_dock_match - see if an acpi object has a _DCK method
*/
bool acpi_dock_match(acpi_handle handle)
{
return acpi_has_method(handle, "_DCK");
}
static acpi_status
acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
void **return_value)
{
long *cap = context;
if (acpi_has_method(handle, "_BCM") &&
acpi_has_method(handle, "_BCL")) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
"support\n"));
*cap |= ACPI_VIDEO_BACKLIGHT;
/* We have backlight support, no need to scan further */
return AE_CTRL_TERMINATE;
}
return 0;
}
/* Returns true if the ACPI object is a video device which can be
* handled by video.ko.
* The device will get a Linux specific CID added in scan.c to
* identify the device as an ACPI graphics device
* Be aware that the graphics device may not be physically present
* Use acpi_video_get_capabilities() to detect general ACPI video
* capabilities of present cards
*/
long acpi_is_video_device(acpi_handle handle)
{
long video_caps = 0;
/* Is this device able to support video switching ? */
if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS"))
video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
/* Is this device able to retrieve a video ROM ? */
if (acpi_has_method(handle, "_ROM"))
video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
/* Is this device able to configure which video head to be POSTed ? */
if (acpi_has_method(handle, "_VPO") &&
acpi_has_method(handle, "_GPD") &&
acpi_has_method(handle, "_SPD"))
video_caps |= ACPI_VIDEO_DEVICE_POSTING;
/* Only check for backlight functionality if one of the above hit. */
if (video_caps)
acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
&video_caps, NULL);
return video_caps;
}
EXPORT_SYMBOL(acpi_is_video_device);
const char *acpi_device_hid(struct acpi_device *device)
{
struct acpi_hardware_id *hid;
if (list_empty(&device->pnp.ids))
return dummy_hid;
hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
return hid->id;
}
EXPORT_SYMBOL(acpi_device_hid);
static void acpi_add_id(struct acpi_device_pnp *pnp, const char *dev_id)
{
struct acpi_hardware_id *id;
id = kmalloc(sizeof(*id), GFP_KERNEL);
if (!id)
return;
id->id = kstrdup_const(dev_id, GFP_KERNEL);
if (!id->id) {
kfree(id);
return;
}
list_add_tail(&id->list, &pnp->ids);
pnp->type.hardware_id = 1;
}
/*
* Old IBM workstations have a DSDT bug wherein the SMBus object
* lacks the SMBUS01 HID and the methods do not have the necessary "_"
* prefix. Work around this.
*/
static bool acpi_ibm_smbus_match(acpi_handle handle)
{
char node_name[ACPI_PATH_SEGMENT_LENGTH];
struct acpi_buffer path = { sizeof(node_name), node_name };
if (!dmi_name_in_vendors("IBM"))
return false;
/* Look for SMBS object */
if (ACPI_FAILURE(acpi_get_name(handle, ACPI_SINGLE_NAME, &path)) ||
strcmp("SMBS", path.pointer))
return false;
/* Does it have the necessary (but misnamed) methods? */
if (acpi_has_method(handle, "SBI") &&
acpi_has_method(handle, "SBR") &&
acpi_has_method(handle, "SBW"))
return true;
return false;
}
static bool acpi_object_is_system_bus(acpi_handle handle)
{
acpi_handle tmp;
if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_SB", &tmp)) &&
tmp == handle)
return true;
if (ACPI_SUCCESS(acpi_get_handle(NULL, "\\_TZ", &tmp)) &&
tmp == handle)
return true;
return false;
}
static void acpi_set_pnp_ids(acpi_handle handle, struct acpi_device_pnp *pnp,
int device_type)
{
acpi_status status;
struct acpi_device_info *info;
struct acpi_pnp_device_id_list *cid_list;
int i;
switch (device_type) {
case ACPI_BUS_TYPE_DEVICE:
if (handle == ACPI_ROOT_OBJECT) {
acpi_add_id(pnp, ACPI_SYSTEM_HID);
break;
}
status = acpi_get_object_info(handle, &info);
if (ACPI_FAILURE(status)) {
pr_err(PREFIX "%s: Error reading device info\n",
__func__);
return;
}
if (info->valid & ACPI_VALID_HID) {
acpi_add_id(pnp, info->hardware_id.string);
pnp->type.platform_id = 1;
}
if (info->valid & ACPI_VALID_CID) {
cid_list = &info->compatible_id_list;
for (i = 0; i < cid_list->count; i++)
acpi_add_id(pnp, cid_list->ids[i].string);
}
if (info->valid & ACPI_VALID_ADR) {
pnp->bus_address = info->address;
pnp->type.bus_address = 1;
}
if (info->valid & ACPI_VALID_UID)
pnp->unique_id = kstrdup(info->unique_id.string,
GFP_KERNEL);
if (info->valid & ACPI_VALID_CLS)
acpi_add_id(pnp, info->class_code.string);
kfree(info);
/*
* Some devices don't reliably have _HIDs & _CIDs, so add
* synthetic HIDs to make sure drivers can find them.
*/
if (acpi_is_video_device(handle))
acpi_add_id(pnp, ACPI_VIDEO_HID);
else if (acpi_bay_match(handle))
acpi_add_id(pnp, ACPI_BAY_HID);
else if (acpi_dock_match(handle))
acpi_add_id(pnp, ACPI_DOCK_HID);
else if (acpi_ibm_smbus_match(handle))
acpi_add_id(pnp, ACPI_SMBUS_IBM_HID);
else if (list_empty(&pnp->ids) &&
acpi_object_is_system_bus(handle)) {
/* \_SB, \_TZ, LNXSYBUS */
acpi_add_id(pnp, ACPI_BUS_HID);
strcpy(pnp->device_name, ACPI_BUS_DEVICE_NAME);
strcpy(pnp->device_class, ACPI_BUS_CLASS);
}
break;
case ACPI_BUS_TYPE_POWER:
acpi_add_id(pnp, ACPI_POWER_HID);
break;
case ACPI_BUS_TYPE_PROCESSOR:
acpi_add_id(pnp, ACPI_PROCESSOR_OBJECT_HID);
break;
case ACPI_BUS_TYPE_THERMAL:
acpi_add_id(pnp, ACPI_THERMAL_HID);
break;
case ACPI_BUS_TYPE_POWER_BUTTON:
acpi_add_id(pnp, ACPI_BUTTON_HID_POWERF);
break;
case ACPI_BUS_TYPE_SLEEP_BUTTON:
acpi_add_id(pnp, ACPI_BUTTON_HID_SLEEPF);
break;
case ACPI_BUS_TYPE_ECDT_EC:
acpi_add_id(pnp, ACPI_ECDT_HID);
break;
}
}
void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
{
struct acpi_hardware_id *id, *tmp;
list_for_each_entry_safe(id, tmp, &pnp->ids, list) {
kfree_const(id->id);
kfree(id);
}
kfree(pnp->unique_id);
}
/**
* acpi_dma_supported - Check DMA support for the specified device.
* @adev: The pointer to acpi device
*
* Return false if DMA is not supported. Otherwise, return true
*/
bool acpi_dma_supported(struct acpi_device *adev)
{
if (!adev)
return false;
if (adev->flags.cca_seen)
return true;
/*
* Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent
* DMA on "Intel platforms". Presumably that includes all x86 and
* ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y.
*/
if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
return true;
return false;
}
/**
* acpi_get_dma_attr - Check the supported DMA attr for the specified device.
* @adev: The pointer to acpi device
*
* Return enum dev_dma_attr.
*/
enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
{
if (!acpi_dma_supported(adev))
return DEV_DMA_NOT_SUPPORTED;
if (adev->flags.coherent_dma)
return DEV_DMA_COHERENT;
else
return DEV_DMA_NON_COHERENT;
}
/**
* acpi_dma_get_range() - Get device DMA parameters.
*
* @dev: device to configure
* @dma_addr: pointer device DMA address result
* @offset: pointer to the DMA offset result
* @size: pointer to DMA range size result
*
* Evaluate DMA regions and return respectively DMA region start, offset
* and size in dma_addr, offset and size on parsing success; it does not
* update the passed in values on failure.
*
* Return 0 on success, < 0 on failure.
*/
int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
u64 *size)
{
struct acpi_device *adev;
LIST_HEAD(list);
struct resource_entry *rentry;
int ret;
struct device *dma_dev = dev;
u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
/*
* Walk the device tree chasing an ACPI companion with a _DMA
* object while we go. Stop if we find a device with an ACPI
* companion containing a _DMA method.
*/
do {
adev = ACPI_COMPANION(dma_dev);
if (adev && acpi_has_method(adev->handle, METHOD_NAME__DMA))
break;
dma_dev = dma_dev->parent;
} while (dma_dev);
if (!dma_dev)
return -ENODEV;
if (!acpi_has_method(adev->handle, METHOD_NAME__CRS)) {
acpi_handle_warn(adev->handle, "_DMA is valid only if _CRS is present\n");
return -EINVAL;
}
ret = acpi_dev_get_dma_resources(adev, &list);
if (ret > 0) {
list_for_each_entry(rentry, &list, node) {
if (dma_offset && rentry->offset != dma_offset) {
ret = -EINVAL;
dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
goto out;
}
dma_offset = rentry->offset;
/* Take lower and upper limits */
if (rentry->res->start < dma_start)
dma_start = rentry->res->start;
if (rentry->res->end > dma_end)
dma_end = rentry->res->end;
}
if (dma_start >= dma_end) {
ret = -EINVAL;
dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
goto out;
}
*dma_addr = dma_start - dma_offset;
len = dma_end - dma_start;
*size = max(len, len + 1);
*offset = dma_offset;
}
out:
acpi_dev_free_resource_list(&list);
return ret >= 0 ? 0 : ret;
}
/**
* acpi_dma_configure - Set-up DMA configuration for the device.
* @dev: The pointer to the device
* @attr: device dma attributes
*/
int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
{
const struct iommu_ops *iommu;
u64 dma_addr = 0, size = 0;
iort_dma_setup(dev, &dma_addr, &size);
iommu = iort_iommu_configure(dev);
if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER)
return -EPROBE_DEFER;
arch_setup_dma_ops(dev, dma_addr, size,
iommu, attr == DEV_DMA_COHERENT);
return 0;
}
EXPORT_SYMBOL_GPL(acpi_dma_configure);
static void acpi_init_coherency(struct acpi_device *adev)
{
unsigned long long cca = 0;
acpi_status status;
struct acpi_device *parent = adev->parent;
if (parent && parent->flags.cca_seen) {
/*
* From ACPI spec, OSPM will ignore _CCA if an ancestor
* already saw one.
*/
adev->flags.cca_seen = 1;
cca = parent->flags.coherent_dma;
} else {
status = acpi_evaluate_integer(adev->handle, "_CCA",
NULL, &cca);
if (ACPI_SUCCESS(status))
adev->flags.cca_seen = 1;
else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
/*
* If architecture does not specify that _CCA is
* required for DMA-able devices (e.g. x86),
* we default to _CCA=1.
*/
cca = 1;
else
acpi_handle_debug(adev->handle,
"ACPI device is missing _CCA.\n");
}
adev->flags.coherent_dma = cca;
}
static int acpi_check_serial_bus_slave(struct acpi_resource *ares, void *data)
{
bool *is_serial_bus_slave_p = data;
if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
return 1;
*is_serial_bus_slave_p = true;
/* no need to do more checking */
return -1;
}
static bool acpi_is_indirect_io_slave(struct acpi_device *device)
{
struct acpi_device *parent = device->parent;
static const struct acpi_device_id indirect_io_hosts[] = {
{"HISI0191", 0},
{}
};
return parent && !acpi_match_device_ids(parent, indirect_io_hosts);
}
static bool acpi_device_enumeration_by_parent(struct acpi_device *device)
{
struct list_head resource_list;
bool is_serial_bus_slave = false;
/*
* These devices have multiple I2cSerialBus resources and an i2c-client
* must be instantiated for each, each with its own i2c_device_id.
* Normally we only instantiate an i2c-client for the first resource,
* using the ACPI HID as id. These special cases are handled by the
* drivers/platform/x86/i2c-multi-instantiate.c driver, which knows
* which i2c_device_id to use for each resource.
*/
static const struct acpi_device_id i2c_multi_instantiate_ids[] = {
{"BSG1160", },
{"INT33FE", },
{}
};
if (acpi_is_indirect_io_slave(device))
return true;
/* Macs use device properties in lieu of _CRS resources */
if (x86_apple_machine &&
(fwnode_property_present(&device->fwnode, "spiSclkPeriod") ||
fwnode_property_present(&device->fwnode, "i2cAddress") ||
fwnode_property_present(&device->fwnode, "baud")))
return true;
/* Instantiate a pdev for the i2c-multi-instantiate drv to bind to */
if (!acpi_match_device_ids(device, i2c_multi_instantiate_ids))
return false;
INIT_LIST_HEAD(&resource_list);
acpi_dev_get_resources(device, &resource_list,
acpi_check_serial_bus_slave,
&is_serial_bus_slave);
acpi_dev_free_resource_list(&resource_list);
return is_serial_bus_slave;
}
void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
int type, unsigned long long sta)
{
INIT_LIST_HEAD(&device->pnp.ids);
device->device_type = type;
device->handle = handle;
device->parent = acpi_bus_get_parent(handle);
device->fwnode.ops = &acpi_device_fwnode_ops;
acpi_set_device_status(device, sta);
acpi_device_get_busid(device);
acpi_set_pnp_ids(handle, &device->pnp, type);
acpi_init_properties(device);
acpi_bus_get_flags(device);
device->flags.match_driver = false;
device->flags.initialized = true;
device->flags.enumeration_by_parent =
acpi_device_enumeration_by_parent(device);
acpi_device_clear_enumerated(device);
device_initialize(&device->dev);
dev_set_uevent_suppress(&device->dev, true);
acpi_init_coherency(device);
/* Assume there are unmet deps until acpi_device_dep_initialize() runs */
device->dep_unmet = 1;
}
void acpi_device_add_finalize(struct acpi_device *device)
{
dev_set_uevent_suppress(&device->dev, false);
kobject_uevent(&device->dev.kobj, KOBJ_ADD);
}
static int acpi_add_single_object(struct acpi_device **child,
acpi_handle handle, int type,
unsigned long long sta)
{
int result;
struct acpi_device *device;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
if (!device) {
printk(KERN_ERR PREFIX "Memory allocation error\n");
return -ENOMEM;
}
acpi_init_device_object(device, handle, type, sta);
/*
* For ACPI_BUS_TYPE_DEVICE getting the status is delayed till here so
* that we can call acpi_bus_get_status() and use its quirk handling.
* Note this must be done before the get power-/wakeup_dev-flags calls.
*/
if (type == ACPI_BUS_TYPE_DEVICE)
if (acpi_bus_get_status(device) < 0)
acpi_set_device_status(device, 0);
acpi_bus_get_power_flags(device);
acpi_bus_get_wakeup_device_flags(device);
result = acpi_device_add(device, acpi_device_release);
if (result) {
acpi_device_release(&device->dev);
return result;
}
acpi_power_add_remove_device(device, true);
acpi_device_add_finalize(device);
acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Added %s [%s] parent %s\n",
dev_name(&device->dev), (char *) buffer.pointer,
device->parent ? dev_name(&device->parent->dev) : "(null)"));
kfree(buffer.pointer);
*child = device;
return 0;
}
static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
void *context)
{
struct resource *res = context;
if (acpi_dev_resource_memory(ares, res))
return AE_CTRL_TERMINATE;
return AE_OK;
}
static bool acpi_device_should_be_hidden(acpi_handle handle)
{
acpi_status status;
struct resource res;
/* Check if it should ignore the UART device */
if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
return false;
/*
* The UART device described in SPCR table is assumed to have only one
* memory resource present. So we only look for the first one here.
*/
status = acpi_walk_resources(handle, METHOD_NAME__CRS,
acpi_get_resource_memory, &res);
if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
return false;
acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
&res.start);
return true;
}
static int acpi_bus_type_and_status(acpi_handle handle, int *type,
unsigned long long *sta)
{
acpi_status status;
acpi_object_type acpi_type;
status = acpi_get_type(handle, &acpi_type);
if (ACPI_FAILURE(status))
return -ENODEV;
switch (acpi_type) {
case ACPI_TYPE_ANY: /* for ACPI_ROOT_OBJECT */
case ACPI_TYPE_DEVICE:
if (acpi_device_should_be_hidden(handle))
return -ENODEV;
*type = ACPI_BUS_TYPE_DEVICE;
/*
* acpi_add_single_object updates this once we've an acpi_device
* so that acpi_bus_get_status' quirk handling can be used.
*/
*sta = ACPI_STA_DEFAULT;
break;
case ACPI_TYPE_PROCESSOR:
*type = ACPI_BUS_TYPE_PROCESSOR;
status = acpi_bus_get_status_handle(handle, sta);
if (ACPI_FAILURE(status))
return -ENODEV;
break;
case ACPI_TYPE_THERMAL:
*type = ACPI_BUS_TYPE_THERMAL;
*sta = ACPI_STA_DEFAULT;
break;
case ACPI_TYPE_POWER:
*type = ACPI_BUS_TYPE_POWER;
*sta = ACPI_STA_DEFAULT;
break;
default:
return -ENODEV;
}
return 0;
}
bool acpi_device_is_present(const struct acpi_device *adev)
{
return adev->status.present || adev->status.functional;
}
static bool acpi_scan_handler_matching(struct acpi_scan_handler *handler,
const char *idstr,
const struct acpi_device_id **matchid)
{
const struct acpi_device_id *devid;
if (handler->match)
return handler->match(idstr, matchid);
for (devid = handler->ids; devid->id[0]; devid++)
if (!strcmp((char *)devid->id, idstr)) {
if (matchid)
*matchid = devid;
return true;
}
return false;
}
static struct acpi_scan_handler *acpi_scan_match_handler(const char *idstr,
const struct acpi_device_id **matchid)
{
struct acpi_scan_handler *handler;
list_for_each_entry(handler, &acpi_scan_handlers_list, list_node)
if (acpi_scan_handler_matching(handler, idstr, matchid))
return handler;
return NULL;
}
void acpi_scan_hotplug_enabled(struct acpi_hotplug_profile *hotplug, bool val)
{
if (!!hotplug->enabled == !!val)
return;
mutex_lock(&acpi_scan_lock);
hotplug->enabled = val;
mutex_unlock(&acpi_scan_lock);
}
static void acpi_scan_init_hotplug(struct acpi_device *adev)
{
struct acpi_hardware_id *hwid;
if (acpi_dock_match(adev->handle) || is_ejectable_bay(adev)) {
acpi_dock_add(adev);
return;
}
list_for_each_entry(hwid, &adev->pnp.ids, list) {
struct acpi_scan_handler *handler;
handler = acpi_scan_match_handler(hwid->id, NULL);
if (handler) {
adev->flags.hotplug_notify = true;
break;
}
}
}
static void acpi_device_dep_initialize(struct acpi_device *adev)
{
struct acpi_dep_data *dep;
struct acpi_handle_list dep_devices;
acpi_status status;
int i;
adev->dep_unmet = 0;
if (!acpi_has_method(adev->handle, "_DEP"))
return;
status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
&dep_devices);
if (ACPI_FAILURE(status)) {
dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
return;
}
for (i = 0; i < dep_devices.count; i++) {
struct acpi_device_info *info;
int skip;
status = acpi_get_object_info(dep_devices.handles[i], &info);
if (ACPI_FAILURE(status)) {
dev_dbg(&adev->dev, "Error reading _DEP device info\n");
continue;
}
/*
* Skip the dependency of Windows System Power
* Management Controller
*/
skip = info->valid & ACPI_VALID_HID &&
!strcmp(info->hardware_id.string, "INT3396");
kfree(info);
if (skip)
continue;
dep = kzalloc(sizeof(struct acpi_dep_data), GFP_KERNEL);
if (!dep)
return;
dep->master = dep_devices.handles[i];
dep->slave = adev->handle;
adev->dep_unmet++;
mutex_lock(&acpi_dep_list_lock);
list_add_tail(&dep->node , &acpi_dep_list);
mutex_unlock(&acpi_dep_list_lock);
}
}
static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl_not_used,
void *not_used, void **return_value)
{
struct acpi_device *device = NULL;
int type;
unsigned long long sta;
int result;
acpi_bus_get_device(handle, &device);
if (device)
goto out;
result = acpi_bus_type_and_status(handle, &type, &sta);
if (result)
return AE_OK;
if (type == ACPI_BUS_TYPE_POWER) {
acpi_add_power_resource(handle);
return AE_OK;
}
acpi_add_single_object(&device, handle, type, sta);
if (!device)
return AE_CTRL_DEPTH;
acpi_scan_init_hotplug(device);
acpi_device_dep_initialize(device);
out:
if (!*return_value)
*return_value = device;
return AE_OK;
}
static void acpi_default_enumeration(struct acpi_device *device)
{
/*
* Do not enumerate devices with enumeration_by_parent flag set as
* they will be enumerated by their respective parents.
*/
if (!device->flags.enumeration_by_parent) {
acpi_create_platform_device(device, NULL);
acpi_device_set_enumerated(device);
} else {
blocking_notifier_call_chain(&acpi_reconfig_chain,
ACPI_RECONFIG_DEVICE_ADD, device);
}
}
static const struct acpi_device_id generic_device_ids[] = {
{ACPI_DT_NAMESPACE_HID, },
{"", },
};
static int acpi_generic_device_attach(struct acpi_device *adev,
const struct acpi_device_id *not_used)
{
/*
* Since ACPI_DT_NAMESPACE_HID is the only ID handled here, the test
* below can be unconditional.
*/
if (adev->data.of_compatible)
acpi_default_enumeration(adev);
return 1;
}
static struct acpi_scan_handler generic_device_handler = {
.ids = generic_device_ids,
.attach = acpi_generic_device_attach,
};
static int acpi_scan_attach_handler(struct acpi_device *device)
{
struct acpi_hardware_id *hwid;
int ret = 0;
list_for_each_entry(hwid, &device->pnp.ids, list) {
const struct acpi_device_id *devid;
struct acpi_scan_handler *handler;
handler = acpi_scan_match_handler(hwid->id, &devid);
if (handler) {
if (!handler->attach) {
device->pnp.type.platform_id = 0;
continue;
}
device->handler = handler;
ret = handler->attach(device, devid);
if (ret > 0)
break;
device->handler = NULL;
if (ret < 0)
break;
}
}
return ret;
}
static void acpi_bus_attach(struct acpi_device *device)
{
struct acpi_device *child;
acpi_handle ejd;
int ret;
if (ACPI_SUCCESS(acpi_bus_get_ejd(device->handle, &ejd)))
register_dock_dependent_device(device, ejd);
acpi_bus_get_status(device);
/* Skip devices that are not present. */
if (!acpi_device_is_present(device)) {
device->flags.initialized = false;
acpi_device_clear_enumerated(device);
device->flags.power_manageable = 0;
return;
}
if (device->handler)
goto ok;
if (!device->flags.initialized) {
device->flags.power_manageable =
device->power.states[ACPI_STATE_D0].flags.valid;
if (acpi_bus_init_power(device))
device->flags.power_manageable = 0;
device->flags.initialized = true;
} else if (device->flags.visited) {
goto ok;
}
ret = acpi_scan_attach_handler(device);
if (ret < 0)
return;
device->flags.match_driver = true;
if (ret > 0 && !device->flags.enumeration_by_parent) {
acpi_device_set_enumerated(device);
goto ok;
}
ret = device_attach(&device->dev);
if (ret < 0)
return;
if (device->pnp.type.platform_id || device->flags.enumeration_by_parent)
acpi_default_enumeration(device);
else
acpi_device_set_enumerated(device);
ok:
list_for_each_entry(child, &device->children, node)
acpi_bus_attach(child);
if (device->handler && device->handler->hotplug.notify_online)
device->handler->hotplug.notify_online(device);
}
void acpi_walk_dep_device_list(acpi_handle handle)
{
struct acpi_dep_data *dep, *tmp;
struct acpi_device *adev;
mutex_lock(&acpi_dep_list_lock);
list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
if (dep->master == handle) {
acpi_bus_get_device(dep->slave, &adev);
if (!adev)
continue;
adev->dep_unmet--;
if (!adev->dep_unmet)
acpi_bus_attach(adev);
list_del(&dep->node);
kfree(dep);
}
}
mutex_unlock(&acpi_dep_list_lock);
}
EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
/**
* acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
* @handle: Root of the namespace scope to scan.
*
* Scan a given ACPI tree (probably recently hot-plugged) and create and add
* found devices.
*
* If no devices were found, -ENODEV is returned, but it does not mean that
* there has been a real error. There just have been no suitable ACPI objects
* in the table trunk from which the kernel could create a device and add an
* appropriate driver.
*
* Must be called under acpi_scan_lock.
*/
int acpi_bus_scan(acpi_handle handle)
{
void *device = NULL;
if (ACPI_SUCCESS(acpi_bus_check_add(handle, 0, NULL, &device)))
acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
acpi_bus_check_add, NULL, NULL, &device);
if (device) {
acpi_bus_attach(device);
return 0;
}
return -ENODEV;
}
EXPORT_SYMBOL(acpi_bus_scan);
/**
* acpi_bus_trim - Detach scan handlers and drivers from ACPI device objects.
* @adev: Root of the ACPI namespace scope to walk.
*
* Must be called under acpi_scan_lock.
*/
void acpi_bus_trim(struct acpi_device *adev)
{
struct acpi_scan_handler *handler = adev->handler;
struct acpi_device *child;
list_for_each_entry_reverse(child, &adev->children, node)
acpi_bus_trim(child);
adev->flags.match_driver = false;
if (handler) {
if (handler->detach)
handler->detach(adev);
adev->handler = NULL;
} else {
device_release_driver(&adev->dev);
}
/*
* Most likely, the device is going away, so put it into D3cold before
* that.
*/
acpi_device_set_power(adev, ACPI_STATE_D3_COLD);
adev->flags.initialized = false;
acpi_device_clear_enumerated(adev);
}
EXPORT_SYMBOL_GPL(acpi_bus_trim);
int acpi_bus_register_early_device(int type)
{
struct acpi_device *device = NULL;
int result;
result = acpi_add_single_object(&device, NULL,
type, ACPI_STA_DEFAULT);
if (result)
return result;
device->flags.match_driver = true;
return device_attach(&device->dev);
}
EXPORT_SYMBOL_GPL(acpi_bus_register_early_device);
static int acpi_bus_scan_fixed(void)
{
int result = 0;
/*
* Enumerate all fixed-feature devices.
*/
if (!(acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON)) {
struct acpi_device *device = NULL;
result = acpi_add_single_object(&device, NULL,
ACPI_BUS_TYPE_POWER_BUTTON,
ACPI_STA_DEFAULT);
if (result)
return result;
device->flags.match_driver = true;
result = device_attach(&device->dev);
if (result < 0)
return result;
device_init_wakeup(&device->dev, true);
}
if (!(acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON)) {
struct acpi_device *device = NULL;
result = acpi_add_single_object(&device, NULL,
ACPI_BUS_TYPE_SLEEP_BUTTON,
ACPI_STA_DEFAULT);
if (result)
return result;
device->flags.match_driver = true;
result = device_attach(&device->dev);
}
return result < 0 ? result : 0;
}
static void __init acpi_get_spcr_uart_addr(void)
{
acpi_status status;
struct acpi_table_spcr *spcr_ptr;
status = acpi_get_table(ACPI_SIG_SPCR, 0,
(struct acpi_table_header **)&spcr_ptr);
if (ACPI_SUCCESS(status))
spcr_uart_addr = spcr_ptr->serial_port.address;
else
printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n");
}
static bool acpi_scan_initialized;
int __init acpi_scan_init(void)
{
int result;
acpi_status status;
struct acpi_table_stao *stao_ptr;
acpi_pci_root_init();
acpi_pci_link_init();
acpi_processor_init();
acpi_lpss_init();
acpi_apd_init();
acpi_cmos_rtc_init();
acpi_container_init();
acpi_memory_hotplug_init();
acpi_watchdog_init();
acpi_pnp_init();
acpi_int340x_thermal_init();
acpi_amba_init();
acpi_init_lpit();
acpi_scan_add_handler(&generic_device_handler);
/*
* If there is STAO table, check whether it needs to ignore the UART
* device in SPCR table.
*/
status = acpi_get_table(ACPI_SIG_STAO, 0,
(struct acpi_table_header **)&stao_ptr);
if (ACPI_SUCCESS(status)) {
if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
printk(KERN_INFO PREFIX "STAO Name List not yet supported.");
if (stao_ptr->ignore_uart)
acpi_get_spcr_uart_addr();
}
acpi_gpe_apply_masked_gpes();
acpi_update_all_gpes();
mutex_lock(&acpi_scan_lock);
/*
* Enumerate devices in the ACPI namespace.
*/
result = acpi_bus_scan(ACPI_ROOT_OBJECT);
if (result)
goto out;
result = acpi_bus_get_device(ACPI_ROOT_OBJECT, &acpi_root);
if (result)
goto out;
/* Fixed feature devices do not exist on HW-reduced platform */
if (!acpi_gbl_reduced_hardware) {
result = acpi_bus_scan_fixed();
if (result) {
acpi_detach_data(acpi_root->handle,
acpi_scan_drop_device);
acpi_device_del(acpi_root);
put_device(&acpi_root->dev);
goto out;
}
}
acpi_scan_initialized = true;
out:
mutex_unlock(&acpi_scan_lock);
return result;
}
static struct acpi_probe_entry *ape;
static int acpi_probe_count;
static DEFINE_MUTEX(acpi_probe_mutex);
static int __init acpi_match_madt(struct acpi_subtable_header *header,
const unsigned long end)
{
if (!ape->subtable_valid || ape->subtable_valid(header, ape))
if (!ape->probe_subtbl(header, end))
acpi_probe_count++;
return 0;
}
int __init __acpi_probe_device_table(struct acpi_probe_entry *ap_head, int nr)
{
int count = 0;
if (acpi_disabled)
return 0;
mutex_lock(&acpi_probe_mutex);
for (ape = ap_head; nr; ape++, nr--) {
if (ACPI_COMPARE_NAME(ACPI_SIG_MADT, ape->id)) {
acpi_probe_count = 0;
acpi_table_parse_madt(ape->type, acpi_match_madt, 0);
count += acpi_probe_count;
} else {
int res;
res = acpi_table_parse(ape->id, ape->probe_table);
if (!res)
count++;
}
}
mutex_unlock(&acpi_probe_mutex);
return count;
}
struct acpi_table_events_work {
struct work_struct work;
void *table;
u32 event;
};
static void acpi_table_events_fn(struct work_struct *work)
{
struct acpi_table_events_work *tew;
tew = container_of(work, struct acpi_table_events_work, work);
if (tew->event == ACPI_TABLE_EVENT_LOAD) {
acpi_scan_lock_acquire();
acpi_bus_scan(ACPI_ROOT_OBJECT);
acpi_scan_lock_release();
}
kfree(tew);
}
void acpi_scan_table_handler(u32 event, void *table, void *context)
{
struct acpi_table_events_work *tew;
if (!acpi_scan_initialized)
return;
if (event != ACPI_TABLE_EVENT_LOAD)
return;
tew = kmalloc(sizeof(*tew), GFP_KERNEL);
if (!tew)
return;
INIT_WORK(&tew->work, acpi_table_events_fn);
tew->table = table;
tew->event = event;
schedule_work(&tew->work);
}
int acpi_reconfig_notifier_register(struct notifier_block *nb)
{
return blocking_notifier_chain_register(&acpi_reconfig_chain, nb);
}
EXPORT_SYMBOL(acpi_reconfig_notifier_register);
int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
{
return blocking_notifier_chain_unregister(&acpi_reconfig_chain, nb);
}
EXPORT_SYMBOL(acpi_reconfig_notifier_unregister);