tegrakernel/kernel/kernel-4.9/drivers/platform/x86/wmi.c

853 lines
20 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/uuid.h>
ACPI_MODULE_NAME("wmi");
MODULE_AUTHOR("Carlos Corbacho");
MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
MODULE_LICENSE("GPL");
#define ACPI_WMI_CLASS "wmi"
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 list_head list;
struct guid_block gblock;
acpi_handle handle;
wmi_notify_handler handler;
void *handler_data;
struct device dev;
};
/*
* 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 void acpi_wmi_notify(struct acpi_device *device, u32 event);
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 = "wmi",
.class = ACPI_WMI_CLASS,
.ids = wmi_device_ids,
.ops = {
.add = acpi_wmi_add,
.remove = acpi_wmi_remove,
.notify = acpi_wmi_notify,
},
};
/*
* 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 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->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->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->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 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->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->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);
/*
* sysfs interface
*/
static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct wmi_block *wblock;
wblock = dev_get_drvdata(dev);
if (!wblock) {
strcat(buf, "\n");
return strlen(buf);
}
return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
}
static DEVICE_ATTR_RO(modalias);
static struct attribute *wmi_attrs[] = {
&dev_attr_modalias.attr,
NULL,
};
ATTRIBUTE_GROUPS(wmi);
static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
{
char guid_string[37];
struct wmi_block *wblock;
if (add_uevent_var(env, "MODALIAS="))
return -ENOMEM;
wblock = dev_get_drvdata(dev);
if (!wblock)
return -ENOMEM;
sprintf(guid_string, "%pUL", wblock->gblock.guid);
strcpy(&env->buf[env->buflen - 1], "wmi:");
memcpy(&env->buf[env->buflen - 1 + 4], guid_string, 36);
env->buflen += 40;
return 0;
}
static void wmi_dev_free(struct device *dev)
{
struct wmi_block *wmi_block = container_of(dev, struct wmi_block, dev);
kfree(wmi_block);
}
static struct class wmi_class = {
.name = "wmi",
.dev_release = wmi_dev_free,
.dev_uevent = wmi_dev_uevent,
.dev_groups = wmi_groups,
};
static int wmi_create_device(const struct guid_block *gblock,
struct wmi_block *wblock, acpi_handle handle)
{
wblock->dev.class = &wmi_class;
dev_set_name(&wblock->dev, "%pUL", gblock->guid);
dev_set_drvdata(&wblock->dev, wblock);
return device_register(&wblock->dev);
}
static void wmi_free_devices(void)
{
struct wmi_block *wblock, *next;
/* Delete devices for all the GUIDs */
list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
list_del(&wblock->list);
if (wblock->dev.class)
device_unregister(&wblock->dev);
else
kfree(wblock);
}
}
static bool guid_already_parsed(const char *guid_string)
{
struct wmi_block *wblock;
list_for_each_entry(wblock, &wmi_block_list, list)
if (memcmp(wblock->gblock.guid, guid_string, 16) == 0)
return true;
return false;
}
/*
* Parse the _WDG method for the GUID data blocks
*/
static int parse_wdg(acpi_handle handle)
{
struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
union acpi_object *obj;
const struct guid_block *gblock;
struct wmi_block *wblock;
acpi_status status;
int retval;
u32 i, total;
status = acpi_evaluate_object(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]);
wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
if (!wblock)
return -ENOMEM;
wblock->handle = handle;
wblock->gblock = 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(gblock[i].guid)) {
retval = wmi_create_device(&gblock[i], wblock, handle);
if (retval) {
wmi_free_devices();
goto out_free_pointer;
}
}
list_add_tail(&wblock->list, &wmi_block_list);
if (debug_event) {
wblock->handler = wmi_notify_debug;
wmi_method_enable(wblock, 1);
}
}
retval = 0;
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(struct acpi_device *device, u32 event)
{
struct guid_block *block;
struct wmi_block *wblock;
struct list_head *p;
list_for_each(p, &wmi_block_list) {
wblock = list_entry(p, struct wmi_block, list);
block = &wblock->gblock;
if ((block->flags & ACPI_WMI_EVENT) &&
(block->notify_id == event)) {
if (wblock->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(
device->pnp.device_class, dev_name(&device->dev),
event, 0);
break;
}
}
}
static int acpi_wmi_remove(struct acpi_device *device)
{
acpi_remove_address_space_handler(device->handle,
ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
wmi_free_devices();
return 0;
}
static int acpi_wmi_add(struct acpi_device *device)
{
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)) {
pr_err("Error installing EC region handler\n");
return -ENODEV;
}
error = parse_wdg(device->handle);
if (error) {
acpi_remove_address_space_handler(device->handle,
ACPI_ADR_SPACE_EC,
&acpi_wmi_ec_space_handler);
pr_err("Failed to parse WDG method\n");
return error;
}
return 0;
}
static int __init acpi_wmi_init(void)
{
int error;
if (acpi_disabled)
return -ENODEV;
error = class_register(&wmi_class);
if (error)
return error;
error = acpi_bus_register_driver(&acpi_wmi_driver);
if (error) {
pr_err("Error loading mapper\n");
class_unregister(&wmi_class);
return error;
}
pr_info("Mapper loaded\n");
return 0;
}
static void __exit acpi_wmi_exit(void)
{
acpi_bus_unregister_driver(&acpi_wmi_driver);
class_unregister(&wmi_class);
pr_info("Mapper unloaded\n");
}
subsys_initcall_sync(acpi_wmi_init);
module_exit(acpi_wmi_exit);