279 lines
6.7 KiB
C
279 lines
6.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* WMI methods for use with dell-smbios
|
|
*
|
|
* Copyright (c) 2017 Dell Inc.
|
|
*/
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/dmi.h>
|
|
#include <linux/list.h>
|
|
#include <linux/module.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/uaccess.h>
|
|
#include <linux/wmi.h>
|
|
#include "dell-smbios.h"
|
|
#include "dell-wmi-descriptor.h"
|
|
|
|
static DEFINE_MUTEX(call_mutex);
|
|
static DEFINE_MUTEX(list_mutex);
|
|
static int wmi_supported;
|
|
|
|
struct misc_bios_flags_structure {
|
|
struct dmi_header header;
|
|
u16 flags0;
|
|
} __packed;
|
|
#define FLAG_HAS_ACPI_WMI 0x02
|
|
|
|
#define DELL_WMI_SMBIOS_GUID "A80593CE-A997-11DA-B012-B622A1EF5492"
|
|
|
|
struct wmi_smbios_priv {
|
|
struct dell_wmi_smbios_buffer *buf;
|
|
struct list_head list;
|
|
struct wmi_device *wdev;
|
|
struct device *child;
|
|
u32 req_buf_size;
|
|
};
|
|
static LIST_HEAD(wmi_list);
|
|
|
|
static inline struct wmi_smbios_priv *get_first_smbios_priv(void)
|
|
{
|
|
return list_first_entry_or_null(&wmi_list,
|
|
struct wmi_smbios_priv,
|
|
list);
|
|
}
|
|
|
|
static int run_smbios_call(struct wmi_device *wdev)
|
|
{
|
|
struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
|
|
struct wmi_smbios_priv *priv;
|
|
struct acpi_buffer input;
|
|
union acpi_object *obj;
|
|
acpi_status status;
|
|
|
|
priv = dev_get_drvdata(&wdev->dev);
|
|
input.length = priv->req_buf_size - sizeof(u64);
|
|
input.pointer = &priv->buf->std;
|
|
|
|
dev_dbg(&wdev->dev, "evaluating: %u/%u [%x,%x,%x,%x]\n",
|
|
priv->buf->std.cmd_class, priv->buf->std.cmd_select,
|
|
priv->buf->std.input[0], priv->buf->std.input[1],
|
|
priv->buf->std.input[2], priv->buf->std.input[3]);
|
|
|
|
status = wmidev_evaluate_method(wdev, 0, 1, &input, &output);
|
|
if (ACPI_FAILURE(status))
|
|
return -EIO;
|
|
obj = (union acpi_object *)output.pointer;
|
|
if (obj->type != ACPI_TYPE_BUFFER) {
|
|
dev_dbg(&wdev->dev, "received type: %d\n", obj->type);
|
|
if (obj->type == ACPI_TYPE_INTEGER)
|
|
dev_dbg(&wdev->dev, "SMBIOS call failed: %llu\n",
|
|
obj->integer.value);
|
|
kfree(output.pointer);
|
|
return -EIO;
|
|
}
|
|
memcpy(input.pointer, obj->buffer.pointer, obj->buffer.length);
|
|
dev_dbg(&wdev->dev, "result: [%08x,%08x,%08x,%08x]\n",
|
|
priv->buf->std.output[0], priv->buf->std.output[1],
|
|
priv->buf->std.output[2], priv->buf->std.output[3]);
|
|
kfree(output.pointer);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dell_smbios_wmi_call(struct calling_interface_buffer *buffer)
|
|
{
|
|
struct wmi_smbios_priv *priv;
|
|
size_t difference;
|
|
size_t size;
|
|
int ret;
|
|
|
|
mutex_lock(&call_mutex);
|
|
priv = get_first_smbios_priv();
|
|
if (!priv) {
|
|
ret = -ENODEV;
|
|
goto out_wmi_call;
|
|
}
|
|
|
|
size = sizeof(struct calling_interface_buffer);
|
|
difference = priv->req_buf_size - sizeof(u64) - size;
|
|
|
|
memset(&priv->buf->ext, 0, difference);
|
|
memcpy(&priv->buf->std, buffer, size);
|
|
ret = run_smbios_call(priv->wdev);
|
|
memcpy(buffer, &priv->buf->std, size);
|
|
out_wmi_call:
|
|
mutex_unlock(&call_mutex);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static long dell_smbios_wmi_filter(struct wmi_device *wdev, unsigned int cmd,
|
|
struct wmi_ioctl_buffer *arg)
|
|
{
|
|
struct wmi_smbios_priv *priv;
|
|
int ret = 0;
|
|
|
|
switch (cmd) {
|
|
case DELL_WMI_SMBIOS_CMD:
|
|
mutex_lock(&call_mutex);
|
|
priv = dev_get_drvdata(&wdev->dev);
|
|
if (!priv) {
|
|
ret = -ENODEV;
|
|
goto fail_smbios_cmd;
|
|
}
|
|
memcpy(priv->buf, arg, priv->req_buf_size);
|
|
if (dell_smbios_call_filter(&wdev->dev, &priv->buf->std)) {
|
|
dev_err(&wdev->dev, "Invalid call %d/%d:%8x\n",
|
|
priv->buf->std.cmd_class,
|
|
priv->buf->std.cmd_select,
|
|
priv->buf->std.input[0]);
|
|
ret = -EFAULT;
|
|
goto fail_smbios_cmd;
|
|
}
|
|
ret = run_smbios_call(priv->wdev);
|
|
if (ret)
|
|
goto fail_smbios_cmd;
|
|
memcpy(arg, priv->buf, priv->req_buf_size);
|
|
fail_smbios_cmd:
|
|
mutex_unlock(&call_mutex);
|
|
break;
|
|
default:
|
|
ret = -ENOIOCTLCMD;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int dell_smbios_wmi_probe(struct wmi_device *wdev, const void *context)
|
|
{
|
|
struct wmi_driver *wdriver =
|
|
container_of(wdev->dev.driver, struct wmi_driver, driver);
|
|
struct wmi_smbios_priv *priv;
|
|
u32 hotfix;
|
|
int count;
|
|
int ret;
|
|
|
|
ret = dell_wmi_get_descriptor_valid();
|
|
if (ret)
|
|
return ret;
|
|
|
|
priv = devm_kzalloc(&wdev->dev, sizeof(struct wmi_smbios_priv),
|
|
GFP_KERNEL);
|
|
if (!priv)
|
|
return -ENOMEM;
|
|
|
|
/* WMI buffer size will be either 4k or 32k depending on machine */
|
|
if (!dell_wmi_get_size(&priv->req_buf_size))
|
|
return -EPROBE_DEFER;
|
|
|
|
/* some SMBIOS calls fail unless BIOS contains hotfix */
|
|
if (!dell_wmi_get_hotfix(&hotfix))
|
|
return -EPROBE_DEFER;
|
|
if (!hotfix) {
|
|
dev_warn(&wdev->dev,
|
|
"WMI SMBIOS userspace interface not supported(%u), try upgrading to a newer BIOS\n",
|
|
hotfix);
|
|
wdriver->filter_callback = NULL;
|
|
}
|
|
|
|
/* add in the length object we will use internally with ioctl */
|
|
priv->req_buf_size += sizeof(u64);
|
|
ret = set_required_buffer_size(wdev, priv->req_buf_size);
|
|
if (ret)
|
|
return ret;
|
|
|
|
count = get_order(priv->req_buf_size);
|
|
priv->buf = (void *)__get_free_pages(GFP_KERNEL, count);
|
|
if (!priv->buf)
|
|
return -ENOMEM;
|
|
|
|
/* ID is used by dell-smbios to set priority of drivers */
|
|
wdev->dev.id = 1;
|
|
ret = dell_smbios_register_device(&wdev->dev, &dell_smbios_wmi_call);
|
|
if (ret)
|
|
goto fail_register;
|
|
|
|
priv->wdev = wdev;
|
|
dev_set_drvdata(&wdev->dev, priv);
|
|
mutex_lock(&list_mutex);
|
|
list_add_tail(&priv->list, &wmi_list);
|
|
mutex_unlock(&list_mutex);
|
|
|
|
return 0;
|
|
|
|
fail_register:
|
|
free_pages((unsigned long)priv->buf, count);
|
|
return ret;
|
|
}
|
|
|
|
static void dell_smbios_wmi_remove(struct wmi_device *wdev)
|
|
{
|
|
struct wmi_smbios_priv *priv = dev_get_drvdata(&wdev->dev);
|
|
int count;
|
|
|
|
mutex_lock(&call_mutex);
|
|
mutex_lock(&list_mutex);
|
|
list_del(&priv->list);
|
|
mutex_unlock(&list_mutex);
|
|
dell_smbios_unregister_device(&wdev->dev);
|
|
count = get_order(priv->req_buf_size);
|
|
free_pages((unsigned long)priv->buf, count);
|
|
mutex_unlock(&call_mutex);
|
|
}
|
|
|
|
static const struct wmi_device_id dell_smbios_wmi_id_table[] = {
|
|
{ .guid_string = DELL_WMI_SMBIOS_GUID },
|
|
{ },
|
|
};
|
|
|
|
static void parse_b1_table(const struct dmi_header *dm)
|
|
{
|
|
struct misc_bios_flags_structure *flags =
|
|
container_of(dm, struct misc_bios_flags_structure, header);
|
|
|
|
/* 4 bytes header, 8 bytes flags */
|
|
if (dm->length < 12)
|
|
return;
|
|
if (dm->handle != 0xb100)
|
|
return;
|
|
if ((flags->flags0 & FLAG_HAS_ACPI_WMI))
|
|
wmi_supported = 1;
|
|
}
|
|
|
|
static void find_b1(const struct dmi_header *dm, void *dummy)
|
|
{
|
|
switch (dm->type) {
|
|
case 0xb1: /* misc bios flags */
|
|
parse_b1_table(dm);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static struct wmi_driver dell_smbios_wmi_driver = {
|
|
.driver = {
|
|
.name = "dell-smbios",
|
|
},
|
|
.probe = dell_smbios_wmi_probe,
|
|
.remove = dell_smbios_wmi_remove,
|
|
.id_table = dell_smbios_wmi_id_table,
|
|
.filter_callback = dell_smbios_wmi_filter,
|
|
};
|
|
|
|
int init_dell_smbios_wmi(void)
|
|
{
|
|
dmi_walk(find_b1, NULL);
|
|
|
|
if (!wmi_supported)
|
|
return -ENODEV;
|
|
|
|
return wmi_driver_register(&dell_smbios_wmi_driver);
|
|
}
|
|
|
|
void exit_dell_smbios_wmi(void)
|
|
{
|
|
if (wmi_supported)
|
|
wmi_driver_unregister(&dell_smbios_wmi_driver);
|
|
}
|
|
|
|
MODULE_DEVICE_TABLE(wmi, dell_smbios_wmi_id_table);
|