// SPDX-License-Identifier: GPL-2.0-or-later
/*
* acpi_utils.c - ACPI Utility Functions ($Revision: 10 $)
*
* Copyright (C) 2001, 2002 Andy Grover <[email protected]>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
*/
#define pr_fmt(fmt) "ACPI: utils: " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/hardirq.h>
#include <linux/acpi.h>
#include <linux/dynamic_debug.h>
#include "internal.h"
#include "sleep.h"
/* --------------------------------------------------------------------------
Object Evaluation Helpers
-------------------------------------------------------------------------- */
static void acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
{
acpi_handle_debug(h, "Evaluate [%s]: %s\n", p, acpi_format_exception(s));
}
acpi_status
acpi_extract_package(union acpi_object *package,
struct acpi_buffer *format, struct acpi_buffer *buffer)
{
u32 size_required = 0;
u32 tail_offset = 0;
char *format_string = NULL;
u32 format_count = 0;
u32 i = 0;
u8 *head = NULL;
u8 *tail = NULL;
if (!package || (package->type != ACPI_TYPE_PACKAGE)
|| (package->package.count < 1)) {
pr_debug("Invalid package argument\n");
return AE_BAD_PARAMETER;
}
if (!format || !format->pointer || (format->length < 1)) {
pr_debug("Invalid format argument\n");
return AE_BAD_PARAMETER;
}
if (!buffer) {
pr_debug("Invalid buffer argument\n");
return AE_BAD_PARAMETER;
}
format_count = (format->length / sizeof(char)) - 1;
if (format_count > package->package.count) {
pr_debug("Format specifies more objects [%d] than present [%d]\n",
format_count, package->package.count);
return AE_BAD_DATA;
}
format_string = format->pointer;
/*
* Calculate size_required.
*/
for (i = 0; i < format_count; i++) {
union acpi_object *element = &(package->package.elements[i]);
switch (element->type) {
case ACPI_TYPE_INTEGER:
switch (format_string[i]) {
case 'N':
size_required += sizeof(u64);
tail_offset += sizeof(u64);
break;
case 'S':
size_required +=
sizeof(char *) + sizeof(u64) +
sizeof(char);
tail_offset += sizeof(char *);
break;
default:
pr_debug("Invalid package element [%d]: got number, expected [%c]\n",
i, format_string[i]);
return AE_BAD_DATA;
}
break;
case ACPI_TYPE_STRING:
case ACPI_TYPE_BUFFER:
switch (format_string[i]) {
case 'S':
size_required +=
sizeof(char *) +
(element->string.length * sizeof(char)) +
sizeof(char);
tail_offset += sizeof(char *);
break;
case 'B':
size_required +=
sizeof(u8 *) + element->buffer.length;
tail_offset += sizeof(u8 *);
break;
default:
pr_debug("Invalid package element [%d] got string/buffer, expected [%c]\n",
i, format_string[i]);
return AE_BAD_DATA;
}
break;
case ACPI_TYPE_LOCAL_REFERENCE:
switch (format_string[i]) {
case 'R':
size_required += sizeof(void *);
tail_offset += sizeof(void *);
break;
default:
pr_debug("Invalid package element [%d] got reference, expected [%c]\n",
i, format_string[i]);
return AE_BAD_DATA;
}
break;
case ACPI_TYPE_PACKAGE:
default:
pr_debug("Unsupported element at index=%d\n", i);
/* TBD: handle nested packages... */
return AE_SUPPORT;
}
}
/*
* Validate output buffer.
*/
if (buffer->length == ACPI_ALLOCATE_BUFFER) {
buffer->pointer = ACPI_ALLOCATE_ZEROED(size_required);
if (!buffer->pointer)
return AE_NO_MEMORY;
buffer->length = size_required;
} else {
if (buffer->length < size_required) {
buffer->length = size_required;
return AE_BUFFER_OVERFLOW;
} else if (buffer->length != size_required ||
!buffer->pointer) {
return AE_BAD_PARAMETER;
}
}
head = buffer->pointer;
tail = buffer->pointer + tail_offset;
/*
* Extract package data.
*/
for (i = 0; i < format_count; i++) {
u8 **pointer = NULL;
union acpi_object *element = &(package->package.elements[i]);
switch (element->type) {
case ACPI_TYPE_INTEGER:
switch (format_string[i]) {
case 'N':
*((u64 *) head) =
element->integer.value;
head += sizeof(u64);
break;
case 'S':
pointer = (u8 **) head;
*pointer = tail;
*((u64 *) tail) =
element->integer.value;
head += sizeof(u64 *);
tail += sizeof(u64);
/* NULL terminate string */
*tail = (char)0;
tail += sizeof(char);
break;
default:
/* Should never get here */
break;
}
break;
case ACPI_TYPE_STRING:
case ACPI_TYPE_BUFFER:
switch (format_string[i]) {
case 'S':
pointer = (u8 **) head;
*pointer = tail;
memcpy(tail, element->string.pointer,
element->string.length);
head += sizeof(char *);
tail += element->string.length * sizeof(char);
/* NULL terminate string */
*tail = (char)0;
tail += sizeof(char);
break;
case 'B':
pointer = (u8 **) head;
*pointer = tail;
memcpy(tail, element->buffer.pointer,
element->buffer.length);
head += sizeof(u8 *);
tail += element->buffer.length;
break;
default:
/* Should never get here */
break;
}
break;
case ACPI_TYPE_LOCAL_REFERENCE:
switch (format_string[i]) {
case 'R':
*(void **)head =
(void *)element->reference.handle;
head += sizeof(void *);
break;
default:
/* Should never get here */
break;
}
break;
case ACPI_TYPE_PACKAGE:
/* TBD: handle nested packages... */
default:
/* Should never get here */
break;
}
}
return AE_OK;
}
EXPORT_SYMBOL(acpi_extract_package);
acpi_status
acpi_evaluate_integer(acpi_handle handle,
acpi_string pathname,
struct acpi_object_list *arguments, unsigned long long *data)
{
acpi_status status = AE_OK;
union acpi_object element;
struct acpi_buffer buffer = { 0, NULL };
if (!data)
return AE_BAD_PARAMETER;
buffer.length = sizeof(union acpi_object);
buffer.pointer = &element;
status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
if (ACPI_FAILURE(status)) {
acpi_util_eval_error(handle, pathname, status);
return status;
}
if (element.type != ACPI_TYPE_INTEGER) {
acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
return AE_BAD_DATA;
}
*data = element.integer.value;
acpi_handle_debug(handle, "Return value [%llu]\n", *data);
return AE_OK;
}
EXPORT_SYMBOL(acpi_evaluate_integer);
int acpi_get_local_u64_address(acpi_handle handle, u64 *addr)
{
acpi_status status;
status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, addr);
if (ACPI_FAILURE(status))
return -ENODATA;
return 0;
}
EXPORT_SYMBOL(acpi_get_local_u64_address);
int acpi_get_local_address(acpi_handle handle, u32 *addr)
{
u64 adr;
int ret;
ret = acpi_get_local_u64_address(handle, &adr);
if (ret < 0)
return ret;
*addr = (u32)adr;
return 0;
}
EXPORT_SYMBOL(acpi_get_local_address);
#define ACPI_MAX_SUB_BUF_SIZE 9
const char *acpi_get_subsystem_id(acpi_handle handle)
{
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
acpi_status status;
const char *sub;
size_t len;
status = acpi_evaluate_object(handle, METHOD_NAME__SUB, NULL, &buffer);
if (ACPI_FAILURE(status)) {
acpi_handle_debug(handle, "Reading ACPI _SUB failed: %#x\n", status);
return ERR_PTR(-ENODATA);
}
obj = buffer.pointer;
if (obj->type == ACPI_TYPE_STRING) {
len = strlen(obj->string.pointer);
if (len < ACPI_MAX_SUB_BUF_SIZE && len > 0) {
sub = kstrdup(obj->string.pointer, GFP_KERNEL);
if (!sub)
sub = ERR_PTR(-ENOMEM);
} else {
acpi_handle_err(handle, "ACPI _SUB Length %zu is Invalid\n", len);
sub = ERR_PTR(-ENODATA);
}
} else {
acpi_handle_warn(handle, "Warning ACPI _SUB did not return a string\n");
sub = ERR_PTR(-ENODATA);
}
acpi_os_free(buffer.pointer);
return sub;
}
EXPORT_SYMBOL_GPL(acpi_get_subsystem_id);
bool acpi_evaluate_reference(acpi_handle handle, acpi_string pathname,
struct acpi_object_list *arguments,
struct acpi_handle_list *list)
{
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *package;
acpi_status status;
bool ret = false;
u32 i;
if (!list)
return false;
/* Evaluate object. */
status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
if (ACPI_FAILURE(status))
goto end;
package = buffer.pointer;
if (buffer.length == 0 || !package ||
package->type != ACPI_TYPE_PACKAGE || !package->package.count)
goto err;
list->count = package->package.count;
list->handles = kcalloc(list->count, sizeof(*list->handles), GFP_KERNEL);
if (!list->handles)
goto err_clear;
/* Extract package data. */
for (i = 0; i < list->count; i++) {
union acpi_object *element = &(package->package.elements[i]);
if (element->type != ACPI_TYPE_LOCAL_REFERENCE ||
!element->reference.handle)
goto err_free;
/* Get the acpi_handle. */
list->handles[i] = element->reference.handle;
acpi_handle_debug(list->handles[i], "Found in reference list\n");
}
ret = true;
end:
kfree(buffer.pointer);
return ret;
err_free:
kfree(list->handles);
list->handles = NULL;
err_clear:
list->count = 0;
err:
acpi_util_eval_error(handle, pathname, status);
goto end;
}
EXPORT_SYMBOL(acpi_evaluate_reference);
/**
* acpi_handle_list_equal - Check if two ACPI handle lists are the same
* @list1: First list to compare.
* @list2: Second list to compare.
*
* Return true if the given ACPI handle lists are of the same size and
* contain the same ACPI handles in the same order. Otherwise, return false.
*/
bool acpi_handle_list_equal(struct acpi_handle_list *list1,
struct acpi_handle_list *list2)
{
return list1->count == list2->count &&
!memcmp(list1->handles, list2->handles,
list1->count * sizeof(*list1->handles));
}
EXPORT_SYMBOL_GPL(acpi_handle_list_equal);
/**
* acpi_handle_list_replace - Replace one ACPI handle list with another
* @dst: ACPI handle list to replace.
* @src: Source ACPI handle list.
*
* Free the handles table in @dst, move the handles table from @src to @dst,
* copy count from @src to @dst and clear @src.
*/
void acpi_handle_list_replace(struct acpi_handle_list *dst,
struct acpi_handle_list *src)
{
if (dst->count)
kfree(dst->handles);
dst->count = src->count;
dst->handles = src->handles;
src->handles = NULL;
src->count = 0;
}
EXPORT_SYMBOL_GPL(acpi_handle_list_replace);
/**
* acpi_handle_list_free - Free the handles table in an ACPI handle list
* @list: ACPI handle list to free.
*
* Free the handles table in @list and clear its count field.
*/
void acpi_handle_list_free(struct acpi_handle_list *list)
{
if (!list->count)
return;
kfree(list->handles);
list->count = 0;
}
EXPORT_SYMBOL_GPL(acpi_handle_list_free);
/**
* acpi_device_dep - Check ACPI device dependency
* @target: ACPI handle of the target ACPI device.
* @match: ACPI handle to look up in the target's _DEP list.
*
* Return true if @match is present in the list returned by _DEP for
* @target or false otherwise.
*/
bool acpi_device_dep(acpi_handle target, acpi_handle match)
{
struct acpi_handle_list dep_devices;
bool ret = false;
int i;
if (!acpi_has_method(target, "_DEP"))
return false;
if (!acpi_evaluate_reference(target, "_DEP", NULL, &dep_devices)) {
acpi_handle_debug(target, "Failed to evaluate _DEP.\n");
return false;
}
for (i = 0; i < dep_devices.count; i++) {
if (dep_devices.handles[i] == match) {
ret = true;
break;
}
}
acpi_handle_list_free(&dep_devices);
return ret;
}
EXPORT_SYMBOL_GPL(acpi_device_dep);
acpi_status
acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
{
acpi_status status;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *output;
status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
if (ACPI_FAILURE(status))
return status;
output = buffer.pointer;
if (!output || output->type != ACPI_TYPE_PACKAGE
|| !output->package.count
|| output->package.elements[0].type != ACPI_TYPE_BUFFER
|| output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
status = AE_TYPE;
goto out;
}
status = acpi_decode_pld_buffer(
output->package.elements[0].buffer.pointer,
output->package.elements[0].buffer.length,
pld);
out:
kfree(buffer.pointer);
return status;
}
EXPORT_SYMBOL(acpi_get_physical_device_location);
/**
* acpi_evaluate_ost: Evaluate _OST for hotplug operations
* @handle: ACPI device handle
* @source_event: source event code
* @status_code: status code
* @status_buf: optional detailed information (NULL if none)
*
* Evaluate _OST for hotplug operations. All ACPI hotplug handlers
* must call this function when evaluating _OST for hotplug operations.
* When the platform does not support _OST, this function has no effect.
*/
acpi_status
acpi_evaluate_ost(acpi_handle handle, u32 source_event, u32 status_code,
struct acpi_buffer *status_buf)
{
union acpi_object params[3] = {
{.type = ACPI_TYPE_INTEGER,},
{.type = ACPI_TYPE_INTEGER,},
{.type = ACPI_TYPE_BUFFER,}
};
struct acpi_object_list arg_list = {3, params};
params[0].integer.value = source_event;
params[1].integer.value = status_code;
if (status_buf != NULL) {
params[2].buffer.pointer = status_buf->pointer;
params[2].buffer.length = status_buf->length;
} else {
params[2].buffer.pointer = NULL;
params[2].buffer.length = 0;
}
return acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
}
EXPORT_SYMBOL(acpi_evaluate_ost);
/**
* acpi_handle_path: Return the object path of handle
* @handle: ACPI device handle
*
* Caller must free the returned buffer
*/
char *acpi_handle_path(acpi_handle handle)
{
struct acpi_buffer buffer = {
.length = ACPI_ALLOCATE_BUFFER,
.pointer = NULL
};
if (in_interrupt() ||
acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
return NULL;
return buffer.pointer;
}
/**
* acpi_handle_printk: Print message with ACPI prefix and object path
* @level: log level
* @handle: ACPI device handle
* @fmt: format string
*
* This function is called through acpi_handle_<level> macros and prints
* a message with ACPI prefix and object path. This function acquires
* the global namespace mutex to obtain an object path. In interrupt
* context, it shows the object path as <n/a>.
*/
void
acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
{
struct va_format vaf;
va_list args;
const char *path;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
path = acpi_handle_path(handle);
printk("%sACPI: %s: %pV", level, path ? path : "<n/a>", &vaf);
va_end(args);
kfree(path);
}
EXPORT_SYMBOL(acpi_handle_printk);
#if defined(CONFIG_DYNAMIC_DEBUG)
/**
* __acpi_handle_debug: pr_debug with ACPI prefix and object path
* @descriptor: Dynamic Debug descriptor
* @handle: ACPI device handle
* @fmt: format string
*
* This function is called through acpi_handle_debug macro and debug
* prints a message with ACPI prefix and object path. This function
* acquires the global namespace mutex to obtain an object path. In
* interrupt context, it shows the object path as <n/a>.
*/
void
__acpi_handle_debug(struct _ddebug *descriptor, acpi_handle handle,
const char *fmt, ...)
{
struct va_format vaf;
va_list args;
const char *path;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
path = acpi_handle_path(handle);
__dynamic_pr_debug(descriptor, "ACPI: %s: %pV", path ? path : "<n/a>", &vaf);
va_end(args);
kfree(path);
}
EXPORT_SYMBOL(__acpi_handle_debug);
#endif
/**
* acpi_evaluation_failure_warn - Log evaluation failure warning.
* @handle: Parent object handle.
* @name: Name of the object whose evaluation has failed.
* @status: Status value returned by the failing object evaluation.
*/
void acpi_evaluation_failure_warn(acpi_handle handle, const char *name,
acpi_status status)
{
acpi_handle_warn(handle, "%s evaluation failed: %s\n", name,
acpi_format_exception(status));
}
EXPORT_SYMBOL_GPL(acpi_evaluation_failure_warn);
/**
* acpi_has_method: Check whether @handle has a method named @name
* @handle: ACPI device handle
* @name: name of object or method
*
* Check whether @handle has a method named @name.
*/
bool acpi_has_method(acpi_handle handle, char *name)
{
acpi_handle tmp;
return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
}
EXPORT_SYMBOL(acpi_has_method);
acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
u64 arg)
{
union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
obj.integer.value = arg;
return acpi_evaluate_object(handle, method, &arg_list, NULL);
}
EXPORT_SYMBOL(acpi_execute_simple_method);
/**
* acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
* @handle: ACPI device handle
*
* Evaluate device's _EJ0 method for hotplug operations.
*/
acpi_status acpi_evaluate_ej0(acpi_handle handle)
{
acpi_status status;
status = acpi_execute_simple_method(handle, "_EJ0", 1);
if (status == AE_NOT_FOUND)
acpi_handle_warn(handle, "No _EJ0 support for device\n");
else if (ACPI_FAILURE(status))
acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
return status;
}
/**
* acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
* @handle: ACPI device handle
* @lock: lock device if non-zero, otherwise unlock device
*
* Evaluate device's _LCK method if present to lock/unlock device
*/
acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
{
acpi_status status;
status = acpi_execute_simple_method(handle, "_LCK", !!lock);
if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
if (lock)
acpi_handle_warn(handle,
"Locking device failed (0x%x)\n", status);
else
acpi_handle_warn(handle,
"Unlocking device failed (0x%x)\n", status);
}
return status;
}
/**
* acpi_evaluate_reg: Evaluate _REG method to register OpRegion presence
* @handle: ACPI device handle
* @space_id: ACPI address space id to register OpRegion presence for
* @function: Parameter to pass to _REG one of ACPI_REG_CONNECT or
* ACPI_REG_DISCONNECT
*
* Evaluate device's _REG method to register OpRegion presence.
*/
acpi_status acpi_evaluate_reg(acpi_handle handle, u8 space_id, u32 function)
{
struct acpi_object_list arg_list;
union acpi_object params[2];
params[0].type = ACPI_TYPE_INTEGER;
params[0].integer.value = space_id;
params[1].type = ACPI_TYPE_INTEGER;
params[1].integer.value = function;
arg_list.count = 2;
arg_list.pointer = params;
return acpi_evaluate_object(handle, "_REG", &arg_list, NULL);
}
EXPORT_SYMBOL(acpi_evaluate_reg);
/**
* acpi_evaluate_dsm - evaluate device's _DSM method
* @handle: ACPI device handle
* @guid: GUID of requested functions, should be 16 bytes
* @rev: revision number of requested function
* @func: requested function number
* @argv4: the function specific parameter
*
* Evaluate device's _DSM method with specified GUID, revision id and
* function number. Caller needs to free the returned object.
*
* Though ACPI defines the fourth parameter for _DSM should be a package,
* some old BIOSes do expect a buffer or an integer etc.
*/
union acpi_object *
acpi_evaluate_dsm(acpi_handle handle, const guid_t *guid, u64 rev, u64 func,
union acpi_object *argv4)
{
acpi_status ret;
struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
union acpi_object params[4];
struct acpi_object_list input = {
.count = 4,
.pointer = params,
};
params[0].type = ACPI_TYPE_BUFFER;
params[0].buffer.length = 16;
params[0].buffer.pointer = (u8 *)guid;
params[1].type = ACPI_TYPE_INTEGER;
params[1].integer.value = rev;
params[2].type = ACPI_TYPE_INTEGER;
params[2].integer.value = func;
if (argv4) {
params[3] = *argv4;
} else {
params[3].type = ACPI_TYPE_PACKAGE;
params[3].package.count = 0;
params[3].package.elements = NULL;
}
ret = acpi_evaluate_object(handle, "_DSM", &input, &buf);
if (ACPI_SUCCESS(ret))
return (union acpi_object *)buf.pointer;
if (ret != AE_NOT_FOUND)
acpi_handle_warn(handle,
"failed to evaluate _DSM %pUb rev:%lld func:%lld (0x%x)\n",
guid, rev, func, ret);
return NULL;
}
EXPORT_SYMBOL(acpi_evaluate_dsm);
/**
* acpi_check_dsm - check if _DSM method supports requested functions.
* @handle: ACPI device handle
* @guid: GUID of requested functions, should be 16 bytes at least
* @rev: revision number of requested functions
* @funcs: bitmap of requested functions
*
* Evaluate device's _DSM method to check whether it supports requested
* functions. Currently only support 64 functions at maximum, should be
* enough for now.
*/
bool acpi_check_dsm(acpi_handle handle, const guid_t *guid, u64 rev, u64 funcs)
{
int i;
u64 mask = 0;
union acpi_object *obj;
if (funcs == 0)
return false;
obj = acpi_evaluate_dsm(handle, guid, rev, 0, NULL);
if (!obj)
return false;
/* For compatibility, old BIOSes may return an integer */
if (obj->type == ACPI_TYPE_INTEGER)
mask = obj->integer.value;
else if (obj->type == ACPI_TYPE_BUFFER)
for (i = 0; i < obj->buffer.length && i < 8; i++)
mask |= (((u64)obj->buffer.pointer[i]) << (i * 8));
ACPI_FREE(obj);
/*
* Bit 0 indicates whether there's support for any functions other than
* function 0 for the specified GUID and revision.
*/
if ((mask & 0x1) && (mask & funcs) == funcs)
return true;
return false;
}
EXPORT_SYMBOL(acpi_check_dsm);
/**
* acpi_dev_uid_to_integer - treat ACPI device _UID as integer
* @adev: ACPI device to get _UID from
* @integer: output buffer for integer
*
* Considers _UID as integer and converts it to @integer.
*
* Returns 0 on success, or negative error code otherwise.
*/
int acpi_dev_uid_to_integer(struct acpi_device *adev, u64 *integer)
{
const char *uid;
if (!adev)
return -ENODEV;
uid = acpi_device_uid(adev);
if (!uid)
return -ENODATA;
return kstrtou64(uid, 0, integer);
}
EXPORT_SYMBOL(acpi_dev_uid_to_integer);
/**
* acpi_dev_found - Detect presence of a given ACPI device in the namespace.
* @hid: Hardware ID of the device.
*
* Return %true if the device was present at the moment of invocation.
* Note that if the device is pluggable, it may since have disappeared.
*
* For this function to work, acpi_bus_scan() must have been executed
* which happens in the subsys_initcall() subsection. Hence, do not
* call from a subsys_initcall() or earlier (use acpi_get_devices()
* instead). Calling from module_init() is fine (which is synonymous
* with device_initcall()).
*/
bool acpi_dev_found(const char *hid)
{
struct acpi_device_bus_id *acpi_device_bus_id;
bool found = false;
mutex_lock(&acpi_device_lock);
list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node)
if (!strcmp(acpi_device_bus_id->bus_id, hid)) {
found = true;
break;
}
mutex_unlock(&acpi_device_lock);
return found;
}
EXPORT_SYMBOL(acpi_dev_found);
struct acpi_dev_match_info {
struct acpi_device_id hid[2];
const char *uid;
s64 hrv;
};
static int acpi_dev_match_cb(struct device *dev, const void *data)
{
struct acpi_device *adev = to_acpi_device(dev);
const struct acpi_dev_match_info *match = data;
unsigned long long hrv;
acpi_status status;
if (acpi_match_device_ids(adev, match->hid))
return 0;
if (match->uid && !acpi_dev_uid_match(adev, match->uid))
return 0;
if (match->hrv == -1)
return 1;
status = acpi_evaluate_integer(adev->handle, "_HRV", NULL, &hrv);
if (ACPI_FAILURE(status))
return 0;
return hrv == match->hrv;
}
/**
* acpi_dev_present - Detect that a given ACPI device is present
* @hid: Hardware ID of the device.
* @uid: Unique ID of the device, pass NULL to not check _UID
* @hrv: Hardware Revision of the device, pass -1 to not check _HRV
*
* Return %true if a matching device was present at the moment of invocation.
* Note that if the device is pluggable, it may since have disappeared.
*
* Note that unlike acpi_dev_found() this function checks the status
* of the device. So for devices which are present in the DSDT, but
* which are disabled (their _STA callback returns 0) this function
* will return false.
*
* For this function to work, acpi_bus_scan() must have been executed
* which happens in the subsys_initcall() subsection. Hence, do not
* call from a subsys_initcall() or earlier (use acpi_get_devices()
* instead). Calling from module_init() is fine (which is synonymous
* with device_initcall()).
*/
bool acpi_dev_present(const char *hid, const char *uid, s64 hrv)
{
struct acpi_dev_match_info match = {};
struct device *dev;
strscpy(match.hid[0].id, hid, sizeof(match.hid[0].id));
match.uid = uid;
match.hrv = hrv;
dev = bus_find_device(&acpi_bus_type, NULL, &match, acpi_dev_match_cb);
put_device(dev);
return !!dev;
}
EXPORT_SYMBOL(acpi_dev_present);
/**
* acpi_dev_get_next_match_dev - Return the next match of ACPI device
* @adev: Pointer to the previous ACPI device matching this @hid, @uid and @hrv
* @hid: Hardware ID of the device.
* @uid: Unique ID of the device, pass NULL to not check _UID
* @hrv: Hardware Revision of the device, pass -1 to not check _HRV
*
* Return the next match of ACPI device if another matching device was present
* at the moment of invocation, or NULL otherwise.
*
* The caller is responsible for invoking acpi_dev_put() on the returned device.
* On the other hand the function invokes acpi_dev_put() on the given @adev
* assuming that its reference counter had been increased beforehand.
*
* See additional information in acpi_dev_present() as well.
*/
struct acpi_device *
acpi_dev_get_next_match_dev(struct acpi_device *adev, const char *hid, const char *uid, s64 hrv)
{
struct device *start = adev ? &adev->dev : NULL;
struct acpi_dev_match_info match = {};
struct device *dev;
strscpy(match.hid[0].id, hid, sizeof(match.hid[0].id));
match.uid = uid;
match.hrv = hrv;
dev = bus_find_device(&acpi_bus_type, start, &match, acpi_dev_match_cb);
acpi_dev_put(adev);
return dev ? to_acpi_device(dev) : NULL;
}
EXPORT_SYMBOL(acpi_dev_get_next_match_dev);
/**
* acpi_dev_get_first_match_dev - Return the first match of ACPI device
* @hid: Hardware ID of the device.
* @uid: Unique ID of the device, pass NULL to not check _UID
* @hrv: Hardware Revision of the device, pass -1 to not check _HRV
*
* Return the first match of ACPI device if a matching device was present
* at the moment of invocation, or NULL otherwise.
*
* The caller is responsible for invoking acpi_dev_put() on the returned device.
*
* See additional information in acpi_dev_present() as well.
*/
struct acpi_device *
acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv)
{
return acpi_dev_get_next_match_dev(NULL, hid, uid, hrv);
}
EXPORT_SYMBOL(acpi_dev_get_first_match_dev);
/**
* acpi_reduced_hardware - Return if this is an ACPI-reduced-hw machine
*
* Return true when running on an ACPI-reduced-hw machine, false otherwise.
*/
bool acpi_reduced_hardware(void)
{
return acpi_gbl_reduced_hardware;
}
EXPORT_SYMBOL_GPL(acpi_reduced_hardware);
/*
* acpi_backlight= handling, this is done here rather then in video_detect.c
* because __setup cannot be used in modules.
*/
char acpi_video_backlight_string[16];
EXPORT_SYMBOL(acpi_video_backlight_string);
static int __init acpi_backlight(char *str)
{
strscpy(acpi_video_backlight_string, str,
sizeof(acpi_video_backlight_string));
return 1;
}
__setup("acpi_backlight=", acpi_backlight);
/**
* acpi_match_platform_list - Check if the system matches with a given list
* @plat: pointer to acpi_platform_list table terminated by a NULL entry
*
* Return the matched index if the system is found in the platform list.
* Otherwise, return a negative error code.
*/
int acpi_match_platform_list(const struct acpi_platform_list *plat)
{
struct acpi_table_header hdr;
int idx = 0;
if (acpi_disabled)
return -ENODEV;
for (; plat->oem_id[0]; plat++, idx++) {
if (ACPI_FAILURE(acpi_get_table_header(plat->table, 0, &hdr)))
continue;
if (strncmp(plat->oem_id, hdr.oem_id, ACPI_OEM_ID_SIZE))
continue;
if (strncmp(plat->oem_table_id, hdr.oem_table_id, ACPI_OEM_TABLE_ID_SIZE))
continue;
if ((plat->pred == all_versions) ||
(plat->pred == less_than_or_equal && hdr.oem_revision <= plat->oem_revision) ||
(plat->pred == greater_than_or_equal && hdr.oem_revision >= plat->oem_revision) ||
(plat->pred == equal && hdr.oem_revision == plat->oem_revision))
return idx;
}
return -ENODEV;
}
EXPORT_SYMBOL(acpi_match_platform_list);
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