linux/drivers/platform/x86/wmi.c
Andy Lutomirski 1686f54445 platform/x86: wmi: Incorporate acpi_install_notify_handler
As a platform driver, acpi_driver.notify will not be available,
so use acpi_install_notify_handler as we will be converting to a
platform driver.

This gives event drivers a simple way to handle events. It
also seems closer to what the Windows docs suggest that Windows
does: it sounds like, in Windows, the mapper is responsible for
called _WED before dispatching to the subdriver.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
[dvhart: merge two development commits and update commit message]
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Cc: Pali Rohár <pali.rohar@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: platform-driver-x86@vger.kernel.org
Cc: linux-acpi@vger.kernel.org
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
2017-06-06 10:15:19 -07:00

1215 lines
29 KiB
C

/*
* ACPI-WMI mapping driver
*
* Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
*
* GUID parsing code from ldm.c is:
* Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
* Copyright (c) 2001-2007 Anton Altaparmakov
* Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/acpi.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/wmi.h>
#include <linux/uuid.h>
ACPI_MODULE_NAME("wmi");
MODULE_AUTHOR("Carlos Corbacho");
MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
MODULE_LICENSE("GPL");
static LIST_HEAD(wmi_block_list);
struct guid_block {
char guid[16];
union {
char object_id[2];
struct {
unsigned char notify_id;
unsigned char reserved;
};
};
u8 instance_count;
u8 flags;
};
struct wmi_block {
struct wmi_device dev;
struct list_head list;
struct guid_block gblock;
struct acpi_device *acpi_device;
wmi_notify_handler handler;
void *handler_data;
bool read_takes_no_args; /* only defined if readable */
};
/*
* If the GUID data block is marked as expensive, we must enable and
* explicitily disable data collection.
*/
#define ACPI_WMI_EXPENSIVE 0x1
#define ACPI_WMI_METHOD 0x2 /* GUID is a method */
#define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
#define ACPI_WMI_EVENT 0x8 /* GUID is an event */
static bool debug_event;
module_param(debug_event, bool, 0444);
MODULE_PARM_DESC(debug_event,
"Log WMI Events [0/1]");
static bool debug_dump_wdg;
module_param(debug_dump_wdg, bool, 0444);
MODULE_PARM_DESC(debug_dump_wdg,
"Dump available WMI interfaces [0/1]");
static int acpi_wmi_remove(struct acpi_device *device);
static int acpi_wmi_add(struct acpi_device *device);
static const struct acpi_device_id wmi_device_ids[] = {
{"PNP0C14", 0},
{"pnp0c14", 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
static struct acpi_driver acpi_wmi_driver = {
.name = "acpi-wmi",
.owner = THIS_MODULE,
.ids = wmi_device_ids,
.ops = {
.add = acpi_wmi_add,
.remove = acpi_wmi_remove,
},
};
/*
* GUID parsing functions
*/
static bool find_guid(const char *guid_string, struct wmi_block **out)
{
uuid_le guid_input;
struct wmi_block *wblock;
struct guid_block *block;
struct list_head *p;
if (uuid_le_to_bin(guid_string, &guid_input))
return false;
list_for_each(p, &wmi_block_list) {
wblock = list_entry(p, struct wmi_block, list);
block = &wblock->gblock;
if (memcmp(block->guid, &guid_input, 16) == 0) {
if (out)
*out = wblock;
return true;
}
}
return false;
}
static int get_subobj_info(acpi_handle handle, const char *pathname,
struct acpi_device_info **info)
{
struct acpi_device_info *dummy_info, **info_ptr;
acpi_handle subobj_handle;
acpi_status status;
status = acpi_get_handle(handle, (char *)pathname, &subobj_handle);
if (status == AE_NOT_FOUND)
return -ENOENT;
else if (ACPI_FAILURE(status))
return -EIO;
info_ptr = info ? info : &dummy_info;
status = acpi_get_object_info(subobj_handle, info_ptr);
if (ACPI_FAILURE(status))
return -EIO;
if (!info)
kfree(dummy_info);
return 0;
}
static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
{
struct guid_block *block = NULL;
char method[5];
acpi_status status;
acpi_handle handle;
block = &wblock->gblock;
handle = wblock->acpi_device->handle;
snprintf(method, 5, "WE%02X", block->notify_id);
status = acpi_execute_simple_method(handle, method, enable);
if (status != AE_OK && status != AE_NOT_FOUND)
return status;
else
return AE_OK;
}
/*
* Exported WMI functions
*/
/**
* wmi_evaluate_method - Evaluate a WMI method
* @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
* @instance: Instance index
* @method_id: Method ID to call
* &in: Buffer containing input for the method call
* &out: Empty buffer to return the method results
*
* Call an ACPI-WMI method
*/
acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
{
struct guid_block *block = NULL;
struct wmi_block *wblock = NULL;
acpi_handle handle;
acpi_status status;
struct acpi_object_list input;
union acpi_object params[3];
char method[5] = "WM";
if (!find_guid(guid_string, &wblock))
return AE_ERROR;
block = &wblock->gblock;
handle = wblock->acpi_device->handle;
if (!(block->flags & ACPI_WMI_METHOD))
return AE_BAD_DATA;
if (block->instance_count < instance)
return AE_BAD_PARAMETER;
input.count = 2;
input.pointer = params;
params[0].type = ACPI_TYPE_INTEGER;
params[0].integer.value = instance;
params[1].type = ACPI_TYPE_INTEGER;
params[1].integer.value = method_id;
if (in) {
input.count = 3;
if (block->flags & ACPI_WMI_STRING) {
params[2].type = ACPI_TYPE_STRING;
} else {
params[2].type = ACPI_TYPE_BUFFER;
}
params[2].buffer.length = in->length;
params[2].buffer.pointer = in->pointer;
}
strncat(method, block->object_id, 2);
status = acpi_evaluate_object(handle, method, &input, out);
return status;
}
EXPORT_SYMBOL_GPL(wmi_evaluate_method);
/**
* wmi_query_block - Return contents of a WMI block
* @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
* @instance: Instance index
* &out: Empty buffer to return the contents of the data block to
*
* Return the contents of an ACPI-WMI data block to a buffer
*/
acpi_status wmi_query_block(const char *guid_string, u8 instance,
struct acpi_buffer *out)
{
struct guid_block *block = NULL;
struct wmi_block *wblock = NULL;
acpi_handle handle;
acpi_status status, wc_status = AE_ERROR;
struct acpi_object_list input;
union acpi_object wq_params[1];
char method[5];
char wc_method[5] = "WC";
if (!guid_string || !out)
return AE_BAD_PARAMETER;
if (!find_guid(guid_string, &wblock))
return AE_ERROR;
block = &wblock->gblock;
handle = wblock->acpi_device->handle;
if (block->instance_count < instance)
return AE_BAD_PARAMETER;
/* Check GUID is a data block */
if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
return AE_ERROR;
input.count = 1;
input.pointer = wq_params;
wq_params[0].type = ACPI_TYPE_INTEGER;
wq_params[0].integer.value = instance;
if (instance == 0 && wblock->read_takes_no_args)
input.count = 0;
/*
* If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
* enable collection.
*/
if (block->flags & ACPI_WMI_EXPENSIVE) {
strncat(wc_method, block->object_id, 2);
/*
* Some GUIDs break the specification by declaring themselves
* expensive, but have no corresponding WCxx method. So we
* should not fail if this happens.
*/
if (acpi_has_method(handle, wc_method))
wc_status = acpi_execute_simple_method(handle,
wc_method, 1);
}
strcpy(method, "WQ");
strncat(method, block->object_id, 2);
status = acpi_evaluate_object(handle, method, &input, out);
/*
* If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
* the WQxx method failed - we should disable collection anyway.
*/
if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
status = acpi_execute_simple_method(handle, wc_method, 0);
}
return status;
}
EXPORT_SYMBOL_GPL(wmi_query_block);
/**
* wmi_set_block - Write to a WMI block
* @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
* @instance: Instance index
* &in: Buffer containing new values for the data block
*
* Write the contents of the input buffer to an ACPI-WMI data block
*/
acpi_status wmi_set_block(const char *guid_string, u8 instance,
const struct acpi_buffer *in)
{
struct guid_block *block = NULL;
struct wmi_block *wblock = NULL;
acpi_handle handle;
struct acpi_object_list input;
union acpi_object params[2];
char method[5] = "WS";
if (!guid_string || !in)
return AE_BAD_DATA;
if (!find_guid(guid_string, &wblock))
return AE_ERROR;
block = &wblock->gblock;
handle = wblock->acpi_device->handle;
if (block->instance_count < instance)
return AE_BAD_PARAMETER;
/* Check GUID is a data block */
if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
return AE_ERROR;
input.count = 2;
input.pointer = params;
params[0].type = ACPI_TYPE_INTEGER;
params[0].integer.value = instance;
if (block->flags & ACPI_WMI_STRING) {
params[1].type = ACPI_TYPE_STRING;
} else {
params[1].type = ACPI_TYPE_BUFFER;
}
params[1].buffer.length = in->length;
params[1].buffer.pointer = in->pointer;
strncat(method, block->object_id, 2);
return acpi_evaluate_object(handle, method, &input, NULL);
}
EXPORT_SYMBOL_GPL(wmi_set_block);
static void wmi_dump_wdg(const struct guid_block *g)
{
pr_info("%pUL:\n", g->guid);
pr_info("\tobject_id: %c%c\n", g->object_id[0], g->object_id[1]);
pr_info("\tnotify_id: %02X\n", g->notify_id);
pr_info("\treserved: %02X\n", g->reserved);
pr_info("\tinstance_count: %d\n", g->instance_count);
pr_info("\tflags: %#x", g->flags);
if (g->flags) {
if (g->flags & ACPI_WMI_EXPENSIVE)
pr_cont(" ACPI_WMI_EXPENSIVE");
if (g->flags & ACPI_WMI_METHOD)
pr_cont(" ACPI_WMI_METHOD");
if (g->flags & ACPI_WMI_STRING)
pr_cont(" ACPI_WMI_STRING");
if (g->flags & ACPI_WMI_EVENT)
pr_cont(" ACPI_WMI_EVENT");
}
pr_cont("\n");
}
static void wmi_notify_debug(u32 value, void *context)
{
struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
acpi_status status;
status = wmi_get_event_data(value, &response);
if (status != AE_OK) {
pr_info("bad event status 0x%x\n", status);
return;
}
obj = (union acpi_object *)response.pointer;
if (!obj)
return;
pr_info("DEBUG Event ");
switch(obj->type) {
case ACPI_TYPE_BUFFER:
pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
break;
case ACPI_TYPE_STRING:
pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
break;
case ACPI_TYPE_INTEGER:
pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
break;
case ACPI_TYPE_PACKAGE:
pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
break;
default:
pr_cont("object type 0x%X\n", obj->type);
}
kfree(obj);
}
/**
* wmi_install_notify_handler - Register handler for WMI events
* @handler: Function to handle notifications
* @data: Data to be returned to handler when event is fired
*
* Register a handler for events sent to the ACPI-WMI mapper device.
*/
acpi_status wmi_install_notify_handler(const char *guid,
wmi_notify_handler handler, void *data)
{
struct wmi_block *block;
acpi_status status = AE_NOT_EXIST;
uuid_le guid_input;
struct list_head *p;
if (!guid || !handler)
return AE_BAD_PARAMETER;
if (uuid_le_to_bin(guid, &guid_input))
return AE_BAD_PARAMETER;
list_for_each(p, &wmi_block_list) {
acpi_status wmi_status;
block = list_entry(p, struct wmi_block, list);
if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
if (block->handler &&
block->handler != wmi_notify_debug)
return AE_ALREADY_ACQUIRED;
block->handler = handler;
block->handler_data = data;
wmi_status = wmi_method_enable(block, 1);
if ((wmi_status != AE_OK) ||
((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
status = wmi_status;
}
}
return status;
}
EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
/**
* wmi_uninstall_notify_handler - Unregister handler for WMI events
*
* Unregister handler for events sent to the ACPI-WMI mapper device.
*/
acpi_status wmi_remove_notify_handler(const char *guid)
{
struct wmi_block *block;
acpi_status status = AE_NOT_EXIST;
uuid_le guid_input;
struct list_head *p;
if (!guid)
return AE_BAD_PARAMETER;
if (uuid_le_to_bin(guid, &guid_input))
return AE_BAD_PARAMETER;
list_for_each(p, &wmi_block_list) {
acpi_status wmi_status;
block = list_entry(p, struct wmi_block, list);
if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
if (!block->handler ||
block->handler == wmi_notify_debug)
return AE_NULL_ENTRY;
if (debug_event) {
block->handler = wmi_notify_debug;
status = AE_OK;
} else {
wmi_status = wmi_method_enable(block, 0);
block->handler = NULL;
block->handler_data = NULL;
if ((wmi_status != AE_OK) ||
((wmi_status == AE_OK) &&
(status == AE_NOT_EXIST)))
status = wmi_status;
}
}
}
return status;
}
EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
/**
* wmi_get_event_data - Get WMI data associated with an event
*
* @event: Event to find
* @out: Buffer to hold event data. out->pointer should be freed with kfree()
*
* Returns extra data associated with an event in WMI.
*/
acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
{
struct acpi_object_list input;
union acpi_object params[1];
struct guid_block *gblock;
struct wmi_block *wblock;
struct list_head *p;
input.count = 1;
input.pointer = params;
params[0].type = ACPI_TYPE_INTEGER;
params[0].integer.value = event;
list_for_each(p, &wmi_block_list) {
wblock = list_entry(p, struct wmi_block, list);
gblock = &wblock->gblock;
if ((gblock->flags & ACPI_WMI_EVENT) &&
(gblock->notify_id == event))
return acpi_evaluate_object(wblock->acpi_device->handle,
"_WED", &input, out);
}
return AE_NOT_FOUND;
}
EXPORT_SYMBOL_GPL(wmi_get_event_data);
/**
* wmi_has_guid - Check if a GUID is available
* @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
*
* Check if a given GUID is defined by _WDG
*/
bool wmi_has_guid(const char *guid_string)
{
return find_guid(guid_string, NULL);
}
EXPORT_SYMBOL_GPL(wmi_has_guid);
static struct wmi_block *dev_to_wblock(struct device *dev)
{
return container_of(dev, struct wmi_block, dev.dev);
}
static struct wmi_device *dev_to_wdev(struct device *dev)
{
return container_of(dev, struct wmi_device, dev);
}
/*
* sysfs interface
*/
static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct wmi_block *wblock = dev_to_wblock(dev);
return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
}
static DEVICE_ATTR_RO(modalias);
static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct wmi_block *wblock = dev_to_wblock(dev);
return sprintf(buf, "%pUL\n", wblock->gblock.guid);
}
static DEVICE_ATTR_RO(guid);
static ssize_t instance_count_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct wmi_block *wblock = dev_to_wblock(dev);
return sprintf(buf, "%d\n", (int)wblock->gblock.instance_count);
}
static DEVICE_ATTR_RO(instance_count);
static ssize_t expensive_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct wmi_block *wblock = dev_to_wblock(dev);
return sprintf(buf, "%d\n",
(wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
}
static DEVICE_ATTR_RO(expensive);
static struct attribute *wmi_attrs[] = {
&dev_attr_modalias.attr,
&dev_attr_guid.attr,
&dev_attr_instance_count.attr,
&dev_attr_expensive.attr,
NULL,
};
ATTRIBUTE_GROUPS(wmi);
static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct wmi_block *wblock = dev_to_wblock(dev);
return sprintf(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
}
static DEVICE_ATTR_RO(notify_id);
static struct attribute *wmi_event_attrs[] = {
&dev_attr_notify_id.attr,
NULL,
};
ATTRIBUTE_GROUPS(wmi_event);
static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct wmi_block *wblock = dev_to_wblock(dev);
return sprintf(buf, "%c%c\n", wblock->gblock.object_id[0],
wblock->gblock.object_id[1]);
}
static DEVICE_ATTR_RO(object_id);
static ssize_t readable_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct wmi_device *wdev = dev_to_wdev(dev);
return sprintf(buf, "%d\n", (int)wdev->readable);
}
static DEVICE_ATTR_RO(readable);
static ssize_t writeable_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct wmi_device *wdev = dev_to_wdev(dev);
return sprintf(buf, "%d\n", (int)wdev->writeable);
}
static DEVICE_ATTR_RO(writeable);
static struct attribute *wmi_data_attrs[] = {
&dev_attr_object_id.attr,
&dev_attr_readable.attr,
&dev_attr_writeable.attr,
NULL,
};
ATTRIBUTE_GROUPS(wmi_data);
static struct attribute *wmi_method_attrs[] = {
&dev_attr_object_id.attr,
NULL,
};
ATTRIBUTE_GROUPS(wmi_method);
static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct wmi_block *wblock = dev_to_wblock(dev);
if (add_uevent_var(env, "MODALIAS=wmi:%pUL", wblock->gblock.guid))
return -ENOMEM;
if (add_uevent_var(env, "WMI_GUID=%pUL", wblock->gblock.guid))
return -ENOMEM;
return 0;
}
static void wmi_dev_release(struct device *dev)
{
struct wmi_block *wblock = dev_to_wblock(dev);
kfree(wblock);
}
static int wmi_dev_match(struct device *dev, struct device_driver *driver)
{
struct wmi_driver *wmi_driver =
container_of(driver, struct wmi_driver, driver);
struct wmi_block *wblock = dev_to_wblock(dev);
const struct wmi_device_id *id = wmi_driver->id_table;
while (id->guid_string) {
uuid_le driver_guid;
if (WARN_ON(uuid_le_to_bin(id->guid_string, &driver_guid)))
continue;
if (!memcmp(&driver_guid, wblock->gblock.guid, 16))
return 1;
id++;
}
return 0;
}
static int wmi_dev_probe(struct device *dev)
{
struct wmi_block *wblock = dev_to_wblock(dev);
struct wmi_driver *wdriver =
container_of(dev->driver, struct wmi_driver, driver);
int ret = 0;
if (ACPI_FAILURE(wmi_method_enable(wblock, 1)))
dev_warn(dev, "failed to enable device -- probing anyway\n");
if (wdriver->probe) {
ret = wdriver->probe(dev_to_wdev(dev));
if (ret != 0 && ACPI_FAILURE(wmi_method_enable(wblock, 0)))
dev_warn(dev, "failed to disable device\n");
}
return ret;
}
static int wmi_dev_remove(struct device *dev)
{
struct wmi_block *wblock = dev_to_wblock(dev);
struct wmi_driver *wdriver =
container_of(dev->driver, struct wmi_driver, driver);
int ret = 0;
if (wdriver->remove)
ret = wdriver->remove(dev_to_wdev(dev));
if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
dev_warn(dev, "failed to disable device\n");
return ret;
}
static struct class wmi_bus_class = {
.name = "wmi_bus",
};
static struct bus_type wmi_bus_type = {
.name = "wmi",
.dev_groups = wmi_groups,
.match = wmi_dev_match,
.uevent = wmi_dev_uevent,
.probe = wmi_dev_probe,
.remove = wmi_dev_remove,
};
static struct device_type wmi_type_event = {
.name = "event",
.groups = wmi_event_groups,
.release = wmi_dev_release,
};
static struct device_type wmi_type_method = {
.name = "method",
.groups = wmi_method_groups,
.release = wmi_dev_release,
};
static struct device_type wmi_type_data = {
.name = "data",
.groups = wmi_data_groups,
.release = wmi_dev_release,
};
static void wmi_create_device(struct device *wmi_bus_dev,
const struct guid_block *gblock,
struct wmi_block *wblock,
struct acpi_device *device)
{
wblock->dev.dev.bus = &wmi_bus_type;
wblock->dev.dev.parent = wmi_bus_dev;
dev_set_name(&wblock->dev.dev, "%pUL", gblock->guid);
if (gblock->flags & ACPI_WMI_EVENT) {
wblock->dev.dev.type = &wmi_type_event;
} else if (gblock->flags & ACPI_WMI_METHOD) {
wblock->dev.dev.type = &wmi_type_method;
} else {
struct acpi_device_info *info;
char method[5];
int result;
wblock->dev.dev.type = &wmi_type_data;
strcpy(method, "WQ");
strncat(method, wblock->gblock.object_id, 2);
result = get_subobj_info(device->handle, method, &info);
if (result == 0) {
wblock->dev.readable = true;
/*
* The Microsoft documentation specifically states:
*
* Data blocks registered with only a single instance
* can ignore the parameter.
*
* ACPICA will get mad at us if we call the method
* with the wrong number of arguments, so check what
* our method expects. (On some Dell laptops, WQxx
* may not be a method at all.)
*/
if (info->type != ACPI_TYPE_METHOD ||
info->param_count == 0)
wblock->read_takes_no_args = true;
kfree(info);
}
strcpy(method, "WS");
strncat(method, wblock->gblock.object_id, 2);
result = get_subobj_info(device->handle, method, NULL);
if (result == 0) {
wblock->dev.writeable = true;
}
}
device_initialize(&wblock->dev.dev);
}
static void wmi_free_devices(struct acpi_device *device)
{
struct wmi_block *wblock, *next;
/* Delete devices for all the GUIDs */
list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
if (wblock->acpi_device == device) {
list_del(&wblock->list);
device_unregister(&wblock->dev.dev);
}
}
}
static bool guid_already_parsed(struct acpi_device *device,
const u8 *guid)
{
struct wmi_block *wblock;
list_for_each_entry(wblock, &wmi_block_list, list) {
if (memcmp(wblock->gblock.guid, guid, 16) == 0) {
/*
* Because we historically didn't track the relationship
* between GUIDs and ACPI nodes, we don't know whether
* we need to suppress GUIDs that are unique on a
* given node but duplicated across nodes.
*/
dev_warn(&device->dev, "duplicate WMI GUID %pUL (first instance was on %s)\n",
guid, dev_name(&wblock->acpi_device->dev));
return true;
}
}
return false;
}
/*
* Parse the _WDG method for the GUID data blocks
*/
static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
{
struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
const struct guid_block *gblock;
struct wmi_block *wblock, *next;
union acpi_object *obj;
acpi_status status;
int retval = 0;
u32 i, total;
status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
if (ACPI_FAILURE(status))
return -ENXIO;
obj = (union acpi_object *) out.pointer;
if (!obj)
return -ENXIO;
if (obj->type != ACPI_TYPE_BUFFER) {
retval = -ENXIO;
goto out_free_pointer;
}
gblock = (const struct guid_block *)obj->buffer.pointer;
total = obj->buffer.length / sizeof(struct guid_block);
for (i = 0; i < total; i++) {
if (debug_dump_wdg)
wmi_dump_wdg(&gblock[i]);
/*
* Some WMI devices, like those for nVidia hooks, have a
* duplicate GUID. It's not clear what we should do in this
* case yet, so for now, we'll just ignore the duplicate
* for device creation.
*/
if (guid_already_parsed(device, gblock[i].guid))
continue;
wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
if (!wblock) {
retval = -ENOMEM;
break;
}
wblock->acpi_device = device;
wblock->gblock = gblock[i];
wmi_create_device(wmi_bus_dev, &gblock[i], wblock, device);
list_add_tail(&wblock->list, &wmi_block_list);
if (debug_event) {
wblock->handler = wmi_notify_debug;
wmi_method_enable(wblock, 1);
}
}
/*
* Now that all of the devices are created, add them to the
* device tree and probe subdrivers.
*/
list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
if (wblock->acpi_device != device)
continue;
retval = device_add(&wblock->dev.dev);
if (retval) {
dev_err(wmi_bus_dev, "failed to register %pULL\n",
wblock->gblock.guid);
if (debug_event)
wmi_method_enable(wblock, 0);
list_del(&wblock->list);
put_device(&wblock->dev.dev);
}
}
out_free_pointer:
kfree(out.pointer);
return retval;
}
/*
* WMI can have EmbeddedControl access regions. In which case, we just want to
* hand these off to the EC driver.
*/
static acpi_status
acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
u32 bits, u64 *value,
void *handler_context, void *region_context)
{
int result = 0, i = 0;
u8 temp = 0;
if ((address > 0xFF) || !value)
return AE_BAD_PARAMETER;
if (function != ACPI_READ && function != ACPI_WRITE)
return AE_BAD_PARAMETER;
if (bits != 8)
return AE_BAD_PARAMETER;
if (function == ACPI_READ) {
result = ec_read(address, &temp);
(*value) |= ((u64)temp) << i;
} else {
temp = 0xff & ((*value) >> i);
result = ec_write(address, temp);
}
switch (result) {
case -EINVAL:
return AE_BAD_PARAMETER;
break;
case -ENODEV:
return AE_NOT_FOUND;
break;
case -ETIME:
return AE_TIME;
break;
default:
return AE_OK;
}
}
static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
void *context)
{
struct guid_block *block;
struct wmi_block *wblock;
struct list_head *p;
bool found_it = false;
list_for_each(p, &wmi_block_list) {
wblock = list_entry(p, struct wmi_block, list);
block = &wblock->gblock;
if (wblock->acpi_device->handle == handle &&
(block->flags & ACPI_WMI_EVENT) &&
(block->notify_id == event))
{
found_it = true;
break;
}
}
if (!found_it)
return;
/* If a driver is bound, then notify the driver. */
if (wblock->dev.dev.driver) {
struct wmi_driver *driver;
struct acpi_object_list input;
union acpi_object params[1];
struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL };
acpi_status status;
driver = container_of(wblock->dev.dev.driver,
struct wmi_driver, driver);
input.count = 1;
input.pointer = params;
params[0].type = ACPI_TYPE_INTEGER;
params[0].integer.value = event;
status = acpi_evaluate_object(wblock->acpi_device->handle,
"_WED", &input, &evdata);
if (ACPI_FAILURE(status)) {
dev_warn(&wblock->dev.dev,
"failed to get event data\n");
return;
}
if (driver->notify)
driver->notify(&wblock->dev,
(union acpi_object *)evdata.pointer);
kfree(evdata.pointer);
} else if (wblock->handler) {
/* Legacy handler */
wblock->handler(event, wblock->handler_data);
}
if (debug_event) {
pr_info("DEBUG Event GUID: %pUL\n",
wblock->gblock.guid);
}
acpi_bus_generate_netlink_event(
wblock->acpi_device->pnp.device_class,
dev_name(&wblock->dev.dev),
event, 0);
}
static int acpi_wmi_remove(struct acpi_device *device)
{
acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
acpi_wmi_notify_handler);
acpi_remove_address_space_handler(device->handle,
ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
wmi_free_devices(device);
device_unregister((struct device *)acpi_driver_data(device));
device->driver_data = NULL;
return 0;
}
static int acpi_wmi_add(struct acpi_device *device)
{
struct device *wmi_bus_dev;
acpi_status status;
int error;
status = acpi_install_address_space_handler(device->handle,
ACPI_ADR_SPACE_EC,
&acpi_wmi_ec_space_handler,
NULL, NULL);
if (ACPI_FAILURE(status)) {
dev_err(&device->dev, "Error installing EC region handler\n");
return -ENODEV;
}
status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
acpi_wmi_notify_handler,
NULL);
if (ACPI_FAILURE(status)) {
dev_err(&device->dev, "Error installing notify handler\n");
error = -ENODEV;
goto err_remove_ec_handler;
}
wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0),
NULL, "wmi_bus-%s", dev_name(&device->dev));
if (IS_ERR(wmi_bus_dev)) {
error = PTR_ERR(wmi_bus_dev);
goto err_remove_notify_handler;
}
device->driver_data = wmi_bus_dev;
error = parse_wdg(wmi_bus_dev, device);
if (error) {
pr_err("Failed to parse WDG method\n");
goto err_remove_busdev;
}
return 0;
err_remove_busdev:
device_unregister(wmi_bus_dev);
err_remove_notify_handler:
acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
acpi_wmi_notify_handler);
err_remove_ec_handler:
acpi_remove_address_space_handler(device->handle,
ACPI_ADR_SPACE_EC,
&acpi_wmi_ec_space_handler);
return error;
}
int __must_check __wmi_driver_register(struct wmi_driver *driver,
struct module *owner)
{
driver->driver.owner = owner;
driver->driver.bus = &wmi_bus_type;
return driver_register(&driver->driver);
}
EXPORT_SYMBOL(__wmi_driver_register);
void wmi_driver_unregister(struct wmi_driver *driver)
{
driver_unregister(&driver->driver);
}
EXPORT_SYMBOL(wmi_driver_unregister);
static int __init acpi_wmi_init(void)
{
int error;
if (acpi_disabled)
return -ENODEV;
error = class_register(&wmi_bus_class);
if (error)
return error;
error = bus_register(&wmi_bus_type);
if (error)
goto err_unreg_class;
error = acpi_bus_register_driver(&acpi_wmi_driver);
if (error) {
pr_err("Error loading mapper\n");
goto err_unreg_bus;
}
return 0;
err_unreg_class:
class_unregister(&wmi_bus_class);
err_unreg_bus:
bus_unregister(&wmi_bus_type);
return error;
}
static void __exit acpi_wmi_exit(void)
{
acpi_bus_unregister_driver(&acpi_wmi_driver);
class_unregister(&wmi_bus_class);
bus_unregister(&wmi_bus_type);
}
subsys_initcall(acpi_wmi_init);
module_exit(acpi_wmi_exit);