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-rw-r--r--drivers/acpi/wmi.c710
1 files changed, 710 insertions, 0 deletions
diff --git a/drivers/acpi/wmi.c b/drivers/acpi/wmi.c
new file mode 100644
index 0000000..36b84ab
--- /dev/null
+++ b/drivers/acpi/wmi.c
@@ -0,0 +1,710 @@
+/*
+ * 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.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/acpi.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+
+ACPI_MODULE_NAME("wmi");
+MODULE_AUTHOR("Carlos Corbacho");
+MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
+MODULE_LICENSE("GPL");
+
+#define ACPI_WMI_CLASS "wmi"
+
+#undef PREFIX
+#define PREFIX "ACPI: WMI: "
+
+static DEFINE_MUTEX(wmi_data_lock);
+
+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;
+};
+
+static struct wmi_block wmi_blocks;
+
+/*
+ * 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 int acpi_wmi_remove(struct acpi_device *device, int type);
+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 = "wmi",
+ .class = ACPI_WMI_CLASS,
+ .ids = wmi_device_ids,
+ .ops = {
+ .add = acpi_wmi_add,
+ .remove = acpi_wmi_remove,
+ },
+};
+
+/*
+ * GUID parsing functions
+ */
+
+/**
+ * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
+ * @src: Pointer to at least 2 characters to convert.
+ *
+ * Convert a two character ASCII hex string to a number.
+ *
+ * Return: 0-255 Success, the byte was parsed correctly
+ * -1 Error, an invalid character was supplied
+ */
+static int wmi_parse_hexbyte(const u8 *src)
+{
+ unsigned int x; /* For correct wrapping */
+ int h;
+
+ /* high part */
+ x = src[0];
+ if (x - '0' <= '9' - '0') {
+ h = x - '0';
+ } else if (x - 'a' <= 'f' - 'a') {
+ h = x - 'a' + 10;
+ } else if (x - 'A' <= 'F' - 'A') {
+ h = x - 'A' + 10;
+ } else {
+ return -1;
+ }
+ h <<= 4;
+
+ /* low part */
+ x = src[1];
+ if (x - '0' <= '9' - '0')
+ return h | (x - '0');
+ if (x - 'a' <= 'f' - 'a')
+ return h | (x - 'a' + 10);
+ if (x - 'A' <= 'F' - 'A')
+ return h | (x - 'A' + 10);
+ return -1;
+}
+
+/**
+ * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
+ * @src: Memory block holding binary GUID (16 bytes)
+ * @dest: Memory block to hold byte swapped binary GUID (16 bytes)
+ *
+ * Byte swap a binary GUID to match it's real GUID value
+ */
+static void wmi_swap_bytes(u8 *src, u8 *dest)
+{
+ int i;
+
+ for (i = 0; i <= 3; i++)
+ memcpy(dest + i, src + (3 - i), 1);
+
+ for (i = 0; i <= 1; i++)
+ memcpy(dest + 4 + i, src + (5 - i), 1);
+
+ for (i = 0; i <= 1; i++)
+ memcpy(dest + 6 + i, src + (7 - i), 1);
+
+ memcpy(dest + 8, src + 8, 8);
+}
+
+/**
+ * wmi_parse_guid - Convert GUID from ASCII to binary
+ * @src: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @dest: Memory block to hold binary GUID (16 bytes)
+ *
+ * N.B. The GUID need not be NULL terminated.
+ *
+ * Return: 'true' @dest contains binary GUID
+ * 'false' @dest contents are undefined
+ */
+static bool wmi_parse_guid(const u8 *src, u8 *dest)
+{
+ static const int size[] = { 4, 2, 2, 2, 6 };
+ int i, j, v;
+
+ if (src[8] != '-' || src[13] != '-' ||
+ src[18] != '-' || src[23] != '-')
+ return false;
+
+ for (j = 0; j < 5; j++, src++) {
+ for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
+ v = wmi_parse_hexbyte(src);
+ if (v < 0)
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static bool find_guid(const char *guid_string, struct wmi_block **out)
+{
+ char tmp[16], guid_input[16];
+ struct wmi_block *wblock;
+ struct guid_block *block;
+ struct list_head *p;
+
+ wmi_parse_guid(guid_string, tmp);
+ wmi_swap_bytes(tmp, guid_input);
+
+ list_for_each(p, &wmi_blocks.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 1;
+ }
+ }
+ return 0;
+}
+
+/*
+ * 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[4] = "WM";
+
+ if (!find_guid(guid_string, &wblock))
+ return AE_BAD_ADDRESS;
+
+ 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, wc_input;
+ union acpi_object wc_params[1], wq_params[1];
+ char method[4];
+ char wc_method[4] = "WC";
+
+ if (!guid_string || !out)
+ return AE_BAD_PARAMETER;
+
+ if (!find_guid(guid_string, &wblock))
+ return AE_BAD_ADDRESS;
+
+ 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_BAD_ADDRESS;
+
+ 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) {
+ wc_input.count = 1;
+ wc_input.pointer = wc_params;
+ wc_params[0].type = ACPI_TYPE_INTEGER;
+ wc_params[0].integer.value = 1;
+
+ 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.
+ */
+ wc_status = acpi_evaluate_object(handle, wc_method,
+ &wc_input, NULL);
+ }
+
+ strcpy(method, "WQ");
+ strncat(method, block->object_id, 2);
+
+ status = acpi_evaluate_object(handle, method, NULL, 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) && wc_status) {
+ wc_params[0].integer.value = 0;
+ status = acpi_evaluate_object(handle,
+ wc_method, &wc_input, NULL);
+ }
+
+ 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[4] = "WS";
+
+ if (!guid_string || !in)
+ return AE_BAD_DATA;
+
+ if (!find_guid(guid_string, &wblock))
+ return AE_BAD_ADDRESS;
+
+ 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_BAD_ADDRESS;
+
+ 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);
+
+/**
+ * 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;
+
+ if (!guid || !handler)
+ return AE_BAD_PARAMETER;
+
+ find_guid(guid, &block);
+ if (!block)
+ return AE_NOT_EXIST;
+
+ if (block->handler)
+ return AE_ALREADY_ACQUIRED;
+
+ block->handler = handler;
+ block->handler_data = data;
+
+ return AE_OK;
+}
+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;
+
+ if (!guid)
+ return AE_BAD_PARAMETER;
+
+ find_guid(guid, &block);
+ if (!block)
+ return AE_NOT_EXIST;
+
+ if (!block->handler)
+ return AE_NULL_ENTRY;
+
+ block->handler = NULL;
+ block->handler_data = NULL;
+
+ return AE_OK;
+}
+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
+ *
+ * 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_blocks.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);
+
+/*
+ * Parse the _WDG method for the GUID data blocks
+ */
+static __init acpi_status parse_wdg(acpi_handle handle)
+{
+ struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
+ union acpi_object *obj;
+ struct guid_block *gblock;
+ struct wmi_block *wblock;
+ acpi_status status;
+ u32 i, total;
+
+ status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
+
+ if (ACPI_FAILURE(status))
+ return status;
+
+ obj = (union acpi_object *) out.pointer;
+
+ if (obj->type != ACPI_TYPE_BUFFER)
+ return AE_ERROR;
+
+ total = obj->buffer.length / sizeof(struct guid_block);
+
+ gblock = kzalloc(obj->buffer.length, GFP_KERNEL);
+ if (!gblock)
+ return AE_NO_MEMORY;
+
+ memcpy(gblock, obj->buffer.pointer, obj->buffer.length);
+
+ for (i = 0; i < total; i++) {
+ wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
+ if (!wblock)
+ return AE_NO_MEMORY;
+
+ wblock->gblock = gblock[i];
+ wblock->handle = handle;
+ list_add_tail(&wblock->list, &wmi_blocks.list);
+ }
+
+ kfree(out.pointer);
+ kfree(gblock);
+
+ return status;
+}
+
+/*
+ * 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, acpi_integer * 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) |= ((acpi_integer)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(acpi_handle handle, u32 event, void *data)
+{
+ struct guid_block *block;
+ struct wmi_block *wblock;
+ struct list_head *p;
+ struct acpi_device *device = data;
+
+ list_for_each(p, &wmi_blocks.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);
+
+ acpi_bus_generate_netlink_event(
+ device->pnp.device_class, device->dev.bus_id,
+ event, 0);
+ break;
+ }
+ }
+}
+
+static int acpi_wmi_remove(struct acpi_device *device, int type)
+{
+ acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+ acpi_wmi_notify);
+
+ acpi_remove_address_space_handler(device->handle,
+ ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
+
+ return 0;
+}
+
+static int __init acpi_wmi_add(struct acpi_device *device)
+{
+ acpi_status status;
+ int result = 0;
+
+ status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+ acpi_wmi_notify, device);
+ if (ACPI_FAILURE(status)) {
+ printk(KERN_ERR PREFIX "Error installing notify handler\n");
+ return -ENODEV;
+ }
+
+ status = acpi_install_address_space_handler(device->handle,
+ ACPI_ADR_SPACE_EC,
+ &acpi_wmi_ec_space_handler,
+ NULL, NULL);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ status = parse_wdg(device->handle);
+ if (ACPI_FAILURE(status)) {
+ printk(KERN_ERR PREFIX "Error installing EC region handler\n");
+ return -ENODEV;
+ }
+
+ return result;
+}
+
+static int __init acpi_wmi_init(void)
+{
+ acpi_status result;
+
+ if (acpi_disabled)
+ return -ENODEV;
+
+ INIT_LIST_HEAD(&wmi_blocks.list);
+
+ result = acpi_bus_register_driver(&acpi_wmi_driver);
+
+ if (result < 0) {
+ printk(KERN_INFO PREFIX "Error loading mapper\n");
+ } else {
+ printk(KERN_INFO PREFIX "Mapper loaded\n");
+ }
+
+ return result;
+}
+
+static void __exit acpi_wmi_exit(void)
+{
+ struct list_head *p, *tmp;
+ struct wmi_block *wblock;
+
+ acpi_bus_unregister_driver(&acpi_wmi_driver);
+
+ list_for_each_safe(p, tmp, &wmi_blocks.list) {
+ wblock = list_entry(p, struct wmi_block, list);
+
+ list_del(p);
+ kfree(wblock);
+ }
+
+ printk(KERN_INFO PREFIX "Mapper unloaded\n");
+}
+
+subsys_initcall(acpi_wmi_init);
+module_exit(acpi_wmi_exit);
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