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android-kvm / linux / 91d1dfae464987aaf6c79ff51d8674880fb3be77 / . / drivers / hwmon / dell-smm-hwmon.c
blob: 0362a13f6525547896a9f70926118a9bbbf72b37 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* dell-smm-hwmon.c -- Linux driver for accessing the SMM BIOS on Dell laptops.
*
* Copyright (C) 2001 Massimo Dal Zotto <dz@debian.org>
*
* Hwmon integration:
* Copyright (C) 2011 Jean Delvare <jdelvare@suse.de>
* Copyright (C) 2013, 2014 Guenter Roeck <linux@roeck-us.net>
* Copyright (C) 2014, 2015 Pali Rohár <pali@kernel.org>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/acpi.h>
#include <linux/capability.h>
#include <linux/cpu.h>
#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/dmi.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/hwmon.h>
#include <linux/init.h>
#include <linux/kconfig.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/string.h>
#include <linux/thermal.h>
#include <linux/types.h>
#include <linux/uaccess.h>
#include <linux/wmi.h>
#include <linux/i8k.h>
#include <asm/unaligned.h>
#define I8K_SMM_FN_STATUS 0x0025
#define I8K_SMM_POWER_STATUS 0x0069
#define I8K_SMM_SET_FAN 0x01a3
#define I8K_SMM_GET_FAN 0x00a3
#define I8K_SMM_GET_SPEED 0x02a3
#define I8K_SMM_GET_FAN_TYPE 0x03a3
#define I8K_SMM_GET_NOM_SPEED 0x04a3
#define I8K_SMM_GET_TEMP 0x10a3
#define I8K_SMM_GET_TEMP_TYPE 0x11a3
#define I8K_SMM_GET_DELL_SIG1 0xfea3
#define I8K_SMM_GET_DELL_SIG2 0xffa3
/* in usecs */
#define DELL_SMM_MAX_DURATION 250000
#define I8K_FAN_MULT 30
#define I8K_FAN_RPM_THRESHOLD 1000
#define I8K_MAX_TEMP 127
#define I8K_FN_NONE 0x00
#define I8K_FN_UP 0x01
#define I8K_FN_DOWN 0x02
#define I8K_FN_MUTE 0x04
#define I8K_FN_MASK 0x07
#define I8K_FN_SHIFT 8
#define I8K_POWER_AC 0x05
#define I8K_POWER_BATTERY 0x01
#define DELL_SMM_WMI_GUID "F1DDEE52-063C-4784-A11E-8A06684B9B01"
#define DELL_SMM_LEGACY_EXECUTE 0x1
#define DELL_SMM_NO_TEMP 10
#define DELL_SMM_NO_FANS 3
struct smm_regs {
unsigned int eax;
unsigned int ebx;
unsigned int ecx;
unsigned int edx;
unsigned int esi;
unsigned int edi;
};
struct dell_smm_ops {
struct device *smm_dev;
int (*smm_call)(struct device *smm_dev, struct smm_regs *regs);
};
struct dell_smm_data {
struct mutex i8k_mutex; /* lock for sensors writes */
char bios_version[4];
char bios_machineid[16];
uint i8k_fan_mult;
uint i8k_pwm_mult;
uint i8k_fan_max;
int temp_type[DELL_SMM_NO_TEMP];
bool fan[DELL_SMM_NO_FANS];
int fan_type[DELL_SMM_NO_FANS];
int *fan_nominal_speed[DELL_SMM_NO_FANS];
const struct dell_smm_ops *ops;
};
struct dell_smm_cooling_data {
u8 fan_num;
struct dell_smm_data *data;
};
MODULE_AUTHOR("Massimo Dal Zotto <dz@debian.org>");
MODULE_AUTHOR("Pali Rohár <pali@kernel.org>");
MODULE_DESCRIPTION("Dell laptop SMM BIOS hwmon driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("i8k");
static bool force;
module_param_unsafe(force, bool, 0);
MODULE_PARM_DESC(force, "Force loading without checking for supported models and features");
static bool ignore_dmi;
module_param(ignore_dmi, bool, 0);
MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
#if IS_ENABLED(CONFIG_I8K)
static bool restricted = true;
module_param(restricted, bool, 0);
MODULE_PARM_DESC(restricted, "Restrict fan control and serial number to CAP_SYS_ADMIN (default: 1)");
static bool power_status;
module_param(power_status, bool, 0600);
MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k (default: 0)");
#endif
static uint fan_mult;
module_param(fan_mult, uint, 0);
MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with (default: autodetect)");
static uint fan_max;
module_param(fan_max, uint, 0);
MODULE_PARM_DESC(fan_max, "Maximum configurable fan speed (default: autodetect)");
static bool disallow_fan_type_call, disallow_fan_support;
static unsigned int manual_fan, auto_fan;
static const char * const temp_labels[] = {
"CPU",
"GPU",
"SODIMM",
"Other",
"Ambient",
"Other",
};
static const char * const fan_labels[] = {
"Processor Fan",
"Motherboard Fan",
"Video Fan",
"Power Supply Fan",
"Chipset Fan",
"Other Fan",
};
static const char * const docking_labels[] = {
"Docking Processor Fan",
"Docking Motherboard Fan",
"Docking Video Fan",
"Docking Power Supply Fan",
"Docking Chipset Fan",
"Docking Other Fan",
};
static inline const char __init *i8k_get_dmi_data(int field)
{
const char *dmi_data = dmi_get_system_info(field);
return dmi_data && *dmi_data ? dmi_data : "?";
}
/*
* Call the System Management Mode BIOS. Code provided by Jonathan Buzzard.
*/
static int i8k_smm_func(void *par)
{
struct smm_regs *regs = par;
unsigned char carry;
/* SMM requires CPU 0 */
if (smp_processor_id() != 0)
return -EBUSY;
asm volatile("out %%al,$0xb2\n\t"
"out %%al,$0x84\n\t"
"setc %0\n"
: "=mr" (carry),
"+a" (regs->eax),
"+b" (regs->ebx),
"+c" (regs->ecx),
"+d" (regs->edx),
"+S" (regs->esi),
"+D" (regs->edi));
if (carry)
return -EINVAL;
return 0;
}
/*
* Call the System Management Mode BIOS.
*/
static int i8k_smm_call(struct device *dummy, struct smm_regs *regs)
{
int ret;
cpus_read_lock();
ret = smp_call_on_cpu(0, i8k_smm_func, regs, true);
cpus_read_unlock();
return ret;
}
static const struct dell_smm_ops i8k_smm_ops = {
.smm_call = i8k_smm_call,
};
/*
* Call the System Management Mode BIOS over WMI.
*/
static ssize_t wmi_parse_register(u8 *buffer, u32 length, unsigned int *reg)
{
__le32 value;
u32 reg_size;
if (length <= sizeof(reg_size))
return -ENODATA;
reg_size = get_unaligned_le32(buffer);
if (!reg_size || reg_size > sizeof(value))
return -ENOMSG;
if (length < sizeof(reg_size) + reg_size)
return -ENODATA;
memcpy_and_pad(&value, sizeof(value), buffer + sizeof(reg_size), reg_size, 0);
*reg = le32_to_cpu(value);
return reg_size + sizeof(reg_size);
}
static int wmi_parse_response(u8 *buffer, u32 length, struct smm_regs *regs)
{
unsigned int *registers[] = {
&regs->eax,
&regs->ebx,
&regs->ecx,
&regs->edx
};
u32 offset = 0;
ssize_t ret;
int i;
for (i = 0; i < ARRAY_SIZE(registers); i++) {
if (offset >= length)
return -ENODATA;
ret = wmi_parse_register(buffer + offset, length - offset, registers[i]);
if (ret < 0)
return ret;
offset += ret;
}
if (offset != length)
return -ENOMSG;
return 0;
}
static int wmi_smm_call(struct device *dev, struct smm_regs *regs)
{
struct wmi_device *wdev = container_of(dev, struct wmi_device, dev);
struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
u32 wmi_payload[] = {
sizeof(regs->eax),
regs->eax,
sizeof(regs->ebx),
regs->ebx,
sizeof(regs->ecx),
regs->ecx,
sizeof(regs->edx),
regs->edx
};
const struct acpi_buffer in = {
.length = sizeof(wmi_payload),
.pointer = &wmi_payload,
};
union acpi_object *obj;
acpi_status status;
int ret;
status = wmidev_evaluate_method(wdev, 0x0, DELL_SMM_LEGACY_EXECUTE, &in, &out);
if (ACPI_FAILURE(status))
return -EIO;
obj = out.pointer;
if (!obj)
return -ENODATA;
if (obj->type != ACPI_TYPE_BUFFER) {
ret = -ENOMSG;
goto err_free;
}
ret = wmi_parse_response(obj->buffer.pointer, obj->buffer.length, regs);
err_free:
kfree(obj);
return ret;
}
static int dell_smm_call(const struct dell_smm_ops *ops, struct smm_regs *regs)
{
unsigned int eax = regs->eax;
unsigned int ebx = regs->ebx;
long long duration;
ktime_t calltime;
int ret;
calltime = ktime_get();
ret = ops->smm_call(ops->smm_dev, regs);
duration = ktime_us_delta(ktime_get(), calltime);
pr_debug("SMM(0x%.4x 0x%.4x) = 0x%.4x status: %d (took %7lld usecs)\n",
eax, ebx, regs->eax & 0xffff, ret, duration);
if (duration > DELL_SMM_MAX_DURATION)
pr_warn_once("SMM call took %lld usecs!\n", duration);
if (ret < 0)
return ret;
if ((regs->eax & 0xffff) == 0xffff || regs->eax == eax)
return -EINVAL;
return 0;
}
/*
* Read the fan status.
*/
static int i8k_get_fan_status(const struct dell_smm_data *data, u8 fan)
{
struct smm_regs regs = {
.eax = I8K_SMM_GET_FAN,
.ebx = fan,
};
if (disallow_fan_support)
return -EINVAL;
return dell_smm_call(data->ops, &regs) ? : regs.eax & 0xff;
}
/*
* Read the fan speed in RPM.
*/
static int i8k_get_fan_speed(const struct dell_smm_data *data, u8 fan)
{
struct smm_regs regs = {
.eax = I8K_SMM_GET_SPEED,
.ebx = fan,
};
if (disallow_fan_support)
return -EINVAL;
return dell_smm_call(data->ops, &regs) ? : (regs.eax & 0xffff) * data->i8k_fan_mult;
}
/*
* Read the fan type.
*/
static int _i8k_get_fan_type(const struct dell_smm_data *data, u8 fan)
{
struct smm_regs regs = {
.eax = I8K_SMM_GET_FAN_TYPE,
.ebx = fan,
};
if (disallow_fan_support || disallow_fan_type_call)
return -EINVAL;
return dell_smm_call(data->ops, &regs) ? : regs.eax & 0xff;
}
static int i8k_get_fan_type(struct dell_smm_data *data, u8 fan)
{
/* I8K_SMM_GET_FAN_TYPE SMM call is expensive, so cache values */
if (data->fan_type[fan] == INT_MIN)
data->fan_type[fan] = _i8k_get_fan_type(data, fan);
return data->fan_type[fan];
}
/*
* Read the fan nominal rpm for specific fan speed.
*/
static int i8k_get_fan_nominal_speed(const struct dell_smm_data *data, u8 fan, int speed)
{
struct smm_regs regs = {
.eax = I8K_SMM_GET_NOM_SPEED,
.ebx = fan | (speed << 8),
};
if (disallow_fan_support)
return -EINVAL;
return dell_smm_call(data->ops, &regs) ? : (regs.eax & 0xffff);
}
/*
* Enable or disable automatic BIOS fan control support
*/
static int i8k_enable_fan_auto_mode(const struct dell_smm_data *data, bool enable)
{
struct smm_regs regs = { };
if (disallow_fan_support)
return -EINVAL;
regs.eax = enable ? auto_fan : manual_fan;
return dell_smm_call(data->ops, &regs);
}
/*
* Set the fan speed (off, low, high, ...).
*/
static int i8k_set_fan(const struct dell_smm_data *data, u8 fan, int speed)
{
struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
if (disallow_fan_support)
return -EINVAL;
speed = (speed < 0) ? 0 : ((speed > data->i8k_fan_max) ? data->i8k_fan_max : speed);
regs.ebx = fan | (speed << 8);
return dell_smm_call(data->ops, &regs);
}
static int i8k_get_temp_type(const struct dell_smm_data *data, u8 sensor)
{
struct smm_regs regs = {
.eax = I8K_SMM_GET_TEMP_TYPE,
.ebx = sensor,
};
return dell_smm_call(data->ops, &regs) ? : regs.eax & 0xff;
}
/*
* Read the cpu temperature.
*/
static int _i8k_get_temp(const struct dell_smm_data *data, u8 sensor)
{
struct smm_regs regs = {
.eax = I8K_SMM_GET_TEMP,
.ebx = sensor,
};
return dell_smm_call(data->ops, &regs) ? : regs.eax & 0xff;
}
static int i8k_get_temp(const struct dell_smm_data *data, u8 sensor)
{
int temp = _i8k_get_temp(data, sensor);
/*
* Sometimes the temperature sensor returns 0x99, which is out of range.
* In this case we retry (once) before returning an error.
# 1003655137 00000058 00005a4b
# 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
# 1003655139 00000054 00005c52
*/
if (temp == 0x99) {
msleep(100);
temp = _i8k_get_temp(data, sensor);
}
/*
* Return -ENODATA for all invalid temperatures.
*
* Known instances are the 0x99 value as seen above as well as
* 0xc1 (193), which may be returned when trying to read the GPU
* temperature if the system supports a GPU and it is currently
* turned off.
*/
if (temp > I8K_MAX_TEMP)
return -ENODATA;
return temp;
}
static int dell_smm_get_signature(const struct dell_smm_ops *ops, int req_fn)
{
struct smm_regs regs = { .eax = req_fn, };
int rc;
rc = dell_smm_call(ops, &regs);
if (rc < 0)
return rc;
return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
}
#if IS_ENABLED(CONFIG_I8K)
/*
* Read the Fn key status.
*/
static int i8k_get_fn_status(const struct dell_smm_data *data)
{
struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, };
int rc;
rc = dell_smm_call(data->ops, &regs);
if (rc < 0)
return rc;
switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) {
case I8K_FN_UP:
return I8K_VOL_UP;
case I8K_FN_DOWN:
return I8K_VOL_DOWN;
case I8K_FN_MUTE:
return I8K_VOL_MUTE;
default:
return 0;
}
}
/*
* Read the power status.
*/
static int i8k_get_power_status(const struct dell_smm_data *data)
{
struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, };
int rc;
rc = dell_smm_call(data->ops, &regs);
if (rc < 0)
return rc;
return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY;
}
/*
* Procfs interface
*/
static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
{
struct dell_smm_data *data = pde_data(file_inode(fp));
int __user *argp = (int __user *)arg;
int speed, err;
int val = 0;
if (!argp)
return -EINVAL;
switch (cmd) {
case I8K_BIOS_VERSION:
if (!isdigit(data->bios_version[0]) || !isdigit(data->bios_version[1]) ||
!isdigit(data->bios_version[2]))
return -EINVAL;
val = (data->bios_version[0] << 16) |
(data->bios_version[1] << 8) | data->bios_version[2];
if (copy_to_user(argp, &val, sizeof(val)))
return -EFAULT;
return 0;
case I8K_MACHINE_ID:
if (restricted && !capable(CAP_SYS_ADMIN))
return -EPERM;
if (copy_to_user(argp, data->bios_machineid, sizeof(data->bios_machineid)))
return -EFAULT;
return 0;
case I8K_FN_STATUS:
val = i8k_get_fn_status(data);
break;
case I8K_POWER_STATUS:
val = i8k_get_power_status(data);
break;
case I8K_GET_TEMP:
val = i8k_get_temp(data, 0);
break;
case I8K_GET_SPEED:
if (copy_from_user(&val, argp, sizeof(int)))
return -EFAULT;
if (val > U8_MAX || val < 0)
return -EINVAL;
val = i8k_get_fan_speed(data, val);
break;
case I8K_GET_FAN:
if (copy_from_user(&val, argp, sizeof(int)))
return -EFAULT;
if (val > U8_MAX || val < 0)
return -EINVAL;
val = i8k_get_fan_status(data, val);
break;
case I8K_SET_FAN:
if (restricted && !capable(CAP_SYS_ADMIN))
return -EPERM;
if (copy_from_user(&val, argp, sizeof(int)))
return -EFAULT;
if (val > U8_MAX || val < 0)
return -EINVAL;
if (copy_from_user(&speed, argp + 1, sizeof(int)))
return -EFAULT;
mutex_lock(&data->i8k_mutex);
err = i8k_set_fan(data, val, speed);
if (err < 0)
val = err;
else
val = i8k_get_fan_status(data, val);
mutex_unlock(&data->i8k_mutex);
break;
default:
return -ENOIOCTLCMD;
}
if (val < 0)
return val;
if (copy_to_user(argp, &val, sizeof(int)))
return -EFAULT;
return 0;
}
/*
* Print the information for /proc/i8k.
*/
static int i8k_proc_show(struct seq_file *seq, void *offset)
{
struct dell_smm_data *data = seq->private;
int fn_key, cpu_temp, ac_power;
int left_fan, right_fan, left_speed, right_speed;
cpu_temp = i8k_get_temp(data, 0); /* 11100 µs */
left_fan = i8k_get_fan_status(data, I8K_FAN_LEFT); /* 580 µs */
right_fan = i8k_get_fan_status(data, I8K_FAN_RIGHT); /* 580 µs */
left_speed = i8k_get_fan_speed(data, I8K_FAN_LEFT); /* 580 µs */
right_speed = i8k_get_fan_speed(data, I8K_FAN_RIGHT); /* 580 µs */
fn_key = i8k_get_fn_status(data); /* 750 µs */
if (power_status)
ac_power = i8k_get_power_status(data); /* 14700 µs */
else
ac_power = -1;
/*
* Info:
*
* 1) Format version (this will change if format changes)
* 2) BIOS version
* 3) BIOS machine ID
* 4) Cpu temperature
* 5) Left fan status
* 6) Right fan status
* 7) Left fan speed
* 8) Right fan speed
* 9) AC power
* 10) Fn Key status
*/
seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
I8K_PROC_FMT,
data->bios_version,
(restricted && !capable(CAP_SYS_ADMIN)) ? "-1" : data->bios_machineid,
cpu_temp,
left_fan, right_fan, left_speed, right_speed,
ac_power, fn_key);
return 0;
}
static int i8k_open_fs(struct inode *inode, struct file *file)
{
return single_open(file, i8k_proc_show, pde_data(inode));
}
static const struct proc_ops i8k_proc_ops = {
.proc_open = i8k_open_fs,
.proc_read = seq_read,
.proc_lseek = seq_lseek,
.proc_release = single_release,
.proc_ioctl = i8k_ioctl,
};
static void i8k_exit_procfs(void *param)
{
remove_proc_entry("i8k", NULL);
}
static void __init i8k_init_procfs(struct device *dev)
{
struct dell_smm_data *data = dev_get_drvdata(dev);
strscpy(data->bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION),
sizeof(data->bios_version));
strscpy(data->bios_machineid, i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
sizeof(data->bios_machineid));
/* Only register exit function if creation was successful */
if (proc_create_data("i8k", 0, NULL, &i8k_proc_ops, data))
devm_add_action_or_reset(dev, i8k_exit_procfs, NULL);
}
#else
static void __init i8k_init_procfs(struct device *dev)
{
}
#endif
static int dell_smm_get_max_state(struct thermal_cooling_device *dev, unsigned long *state)
{
struct dell_smm_cooling_data *cdata = dev->devdata;
*state = cdata->data->i8k_fan_max;
return 0;
}
static int dell_smm_get_cur_state(struct thermal_cooling_device *dev, unsigned long *state)
{
struct dell_smm_cooling_data *cdata = dev->devdata;
int ret;
ret = i8k_get_fan_status(cdata->data, cdata->fan_num);
if (ret < 0)
return ret;
*state = ret;
return 0;
}
static int dell_smm_set_cur_state(struct thermal_cooling_device *dev, unsigned long state)
{
struct dell_smm_cooling_data *cdata = dev->devdata;
struct dell_smm_data *data = cdata->data;
int ret;
if (state > data->i8k_fan_max)
return -EINVAL;
mutex_lock(&data->i8k_mutex);
ret = i8k_set_fan(data, cdata->fan_num, (int)state);
mutex_unlock(&data->i8k_mutex);
return ret;
}
static const struct thermal_cooling_device_ops dell_smm_cooling_ops = {
.get_max_state = dell_smm_get_max_state,
.get_cur_state = dell_smm_get_cur_state,
.set_cur_state = dell_smm_set_cur_state,
};
static umode_t dell_smm_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
int channel)
{
const struct dell_smm_data *data = drvdata;
switch (type) {
case hwmon_temp:
switch (attr) {
case hwmon_temp_input:
/* _i8k_get_temp() is fine since we do not care about the actual value */
if (data->temp_type[channel] >= 0 || _i8k_get_temp(data, channel) >= 0)
return 0444;
break;
case hwmon_temp_label:
if (data->temp_type[channel] >= 0)
return 0444;
break;
default:
break;
}
break;
case hwmon_fan:
if (disallow_fan_support)
break;
switch (attr) {
case hwmon_fan_input:
if (data->fan[channel])
return 0444;
break;
case hwmon_fan_label:
if (data->fan[channel] && !disallow_fan_type_call)
return 0444;
break;
case hwmon_fan_min:
case hwmon_fan_max:
case hwmon_fan_target:
if (data->fan_nominal_speed[channel])
return 0444;
break;
default:
break;
}
break;
case hwmon_pwm:
if (disallow_fan_support)
break;
switch (attr) {
case hwmon_pwm_input:
if (data->fan[channel])
return 0644;
break;
case hwmon_pwm_enable:
if (auto_fan)
/*
* There is no command for retrieve the current status
* from BIOS, and userspace/firmware itself can change
* it.
* Thus we can only provide write-only access for now.
*/
return 0200;
break;
default:
break;
}
break;
default:
break;
}
return 0;
}
static int dell_smm_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
long *val)
{
struct dell_smm_data *data = dev_get_drvdata(dev);
int mult = data->i8k_fan_mult;
int ret;
switch (type) {
case hwmon_temp:
switch (attr) {
case hwmon_temp_input:
ret = i8k_get_temp(data, channel);
if (ret < 0)
return ret;
*val = ret * 1000;
return 0;
default:
break;
}
break;
case hwmon_fan:
switch (attr) {
case hwmon_fan_input:
ret = i8k_get_fan_speed(data, channel);
if (ret < 0)
return ret;
*val = ret;
return 0;
case hwmon_fan_min:
*val = data->fan_nominal_speed[channel][0] * mult;
return 0;
case hwmon_fan_max:
*val = data->fan_nominal_speed[channel][data->i8k_fan_max] * mult;
return 0;
case hwmon_fan_target:
ret = i8k_get_fan_status(data, channel);
if (ret < 0)
return ret;
if (ret > data->i8k_fan_max)
ret = data->i8k_fan_max;
*val = data->fan_nominal_speed[channel][ret] * mult;
return 0;
default:
break;
}
break;
case hwmon_pwm:
switch (attr) {
case hwmon_pwm_input:
ret = i8k_get_fan_status(data, channel);
if (ret < 0)
return ret;
*val = clamp_val(ret * data->i8k_pwm_mult, 0, 255);
return 0;
default:
break;
}
break;
default:
break;
}
return -EOPNOTSUPP;
}
static const char *dell_smm_fan_label(struct dell_smm_data *data, int channel)
{
bool dock = false;
int type = i8k_get_fan_type(data, channel);
if (type < 0)
return ERR_PTR(type);
if (type & 0x10) {
dock = true;
type &= 0x0F;
}
if (type >= ARRAY_SIZE(fan_labels))
type = ARRAY_SIZE(fan_labels) - 1;
return dock ? docking_labels[type] : fan_labels[type];
}
static int dell_smm_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr,
int channel, const char **str)
{
struct dell_smm_data *data = dev_get_drvdata(dev);
switch (type) {
case hwmon_temp:
switch (attr) {
case hwmon_temp_label:
*str = temp_labels[data->temp_type[channel]];
return 0;
default:
break;
}
break;
case hwmon_fan:
switch (attr) {
case hwmon_fan_label:
*str = dell_smm_fan_label(data, channel);
return PTR_ERR_OR_ZERO(*str);
default:
break;
}
break;
default:
break;
}
return -EOPNOTSUPP;
}
static int dell_smm_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
long val)
{
struct dell_smm_data *data = dev_get_drvdata(dev);
unsigned long pwm;
bool enable;
int err;
switch (type) {
case hwmon_pwm:
switch (attr) {
case hwmon_pwm_input:
pwm = clamp_val(DIV_ROUND_CLOSEST(val, data->i8k_pwm_mult), 0,
data->i8k_fan_max);
mutex_lock(&data->i8k_mutex);
err = i8k_set_fan(data, channel, pwm);
mutex_unlock(&data->i8k_mutex);
if (err < 0)
return err;
return 0;
case hwmon_pwm_enable:
if (!val)
return -EINVAL;
if (val == 1)
enable = false;
else
enable = true;
mutex_lock(&data->i8k_mutex);
err = i8k_enable_fan_auto_mode(data, enable);
mutex_unlock(&data->i8k_mutex);
if (err < 0)
return err;
return 0;
default:
break;
}
break;
default:
break;
}
return -EOPNOTSUPP;
}
static const struct hwmon_ops dell_smm_ops = {
.is_visible = dell_smm_is_visible,
.read = dell_smm_read,
.read_string = dell_smm_read_string,
.write = dell_smm_write,
};
static const struct hwmon_channel_info * const dell_smm_info[] = {
HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
HWMON_CHANNEL_INFO(temp,
HWMON_T_INPUT | HWMON_T_LABEL,
HWMON_T_INPUT | HWMON_T_LABEL,
HWMON_T_INPUT | HWMON_T_LABEL,
HWMON_T_INPUT | HWMON_T_LABEL,
HWMON_T_INPUT | HWMON_T_LABEL,
HWMON_T_INPUT | HWMON_T_LABEL,
HWMON_T_INPUT | HWMON_T_LABEL,
HWMON_T_INPUT | HWMON_T_LABEL,
HWMON_T_INPUT | HWMON_T_LABEL,
HWMON_T_INPUT | HWMON_T_LABEL
),
HWMON_CHANNEL_INFO(fan,
HWMON_F_INPUT | HWMON_F_LABEL | HWMON_F_MIN | HWMON_F_MAX |
HWMON_F_TARGET,
HWMON_F_INPUT | HWMON_F_LABEL | HWMON_F_MIN | HWMON_F_MAX |
HWMON_F_TARGET,
HWMON_F_INPUT | HWMON_F_LABEL | HWMON_F_MIN | HWMON_F_MAX |
HWMON_F_TARGET
),
HWMON_CHANNEL_INFO(pwm,
HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
HWMON_PWM_INPUT,
HWMON_PWM_INPUT
),
NULL
};
static const struct hwmon_chip_info dell_smm_chip_info = {
.ops = &dell_smm_ops,
.info = dell_smm_info,
};
static int dell_smm_init_cdev(struct device *dev, u8 fan_num)
{
struct dell_smm_data *data = dev_get_drvdata(dev);
struct thermal_cooling_device *cdev;
struct dell_smm_cooling_data *cdata;
int ret = 0;
char *name;
name = kasprintf(GFP_KERNEL, "dell-smm-fan%u", fan_num + 1);
if (!name)
return -ENOMEM;
cdata = devm_kmalloc(dev, sizeof(*cdata), GFP_KERNEL);
if (cdata) {
cdata->fan_num = fan_num;
cdata->data = data;
cdev = devm_thermal_of_cooling_device_register(dev, NULL, name, cdata,
&dell_smm_cooling_ops);
if (IS_ERR(cdev)) {
devm_kfree(dev, cdata);
ret = PTR_ERR(cdev);
}
} else {
ret = -ENOMEM;
}
kfree(name);
return ret;
}
static int dell_smm_init_hwmon(struct device *dev)
{
struct dell_smm_data *data = dev_get_drvdata(dev);
struct device *dell_smm_hwmon_dev;
int state, err;
u8 i;
for (i = 0; i < DELL_SMM_NO_TEMP; i++) {
data->temp_type[i] = i8k_get_temp_type(data, i);
if (data->temp_type[i] < 0)
continue;
if (data->temp_type[i] >= ARRAY_SIZE(temp_labels))
data->temp_type[i] = ARRAY_SIZE(temp_labels) - 1;
}
for (i = 0; i < DELL_SMM_NO_FANS; i++) {
data->fan_type[i] = INT_MIN;
err = i8k_get_fan_status(data, i);
if (err < 0)
err = i8k_get_fan_type(data, i);
if (err < 0)
continue;
data->fan[i] = true;
/* the cooling device is not critical, ignore failures */
if (IS_REACHABLE(CONFIG_THERMAL)) {
err = dell_smm_init_cdev(dev, i);
if (err < 0)
dev_warn(dev, "Failed to register cooling device for fan %u\n",
i + 1);
}
data->fan_nominal_speed[i] = devm_kmalloc_array(dev, data->i8k_fan_max + 1,
sizeof(*data->fan_nominal_speed[i]),
GFP_KERNEL);
if (!data->fan_nominal_speed[i])
continue;
for (state = 0; state <= data->i8k_fan_max; state++) {
err = i8k_get_fan_nominal_speed(data, i, state);
if (err < 0) {
/* Mark nominal speed table as invalid in case of error */
devm_kfree(dev, data->fan_nominal_speed[i]);
data->fan_nominal_speed[i] = NULL;
break;
}
data->fan_nominal_speed[i][state] = err;
/*
* Autodetect fan multiplier based on nominal rpm if multiplier
* was not specified as module param or in DMI. If fan reports
* rpm value too high then set multiplier to 1.
*/
if (!fan_mult && err > I8K_FAN_RPM_THRESHOLD)
data->i8k_fan_mult = 1;
}
}
dell_smm_hwmon_dev = devm_hwmon_device_register_with_info(dev, "dell_smm", data,
&dell_smm_chip_info, NULL);
return PTR_ERR_OR_ZERO(dell_smm_hwmon_dev);
}
static int dell_smm_init_data(struct device *dev, const struct dell_smm_ops *ops)
{
struct dell_smm_data *data;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
mutex_init(&data->i8k_mutex);
dev_set_drvdata(dev, data);
data->ops = ops;
/* All options must not be 0 */
data->i8k_fan_mult = fan_mult ? : I8K_FAN_MULT;
data->i8k_fan_max = fan_max ? : I8K_FAN_HIGH;
data->i8k_pwm_mult = DIV_ROUND_UP(255, data->i8k_fan_max);
return 0;
}
static const struct dmi_system_id i8k_dmi_table[] __initconst = {
{
.ident = "Dell G5 5590",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "G5 5590"),
},
},
{
.ident = "Dell G5 5505",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "G5 5505"),
},
},
{
.ident = "Dell Inspiron",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
},
},
{
.ident = "Dell Latitude",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
},
},
{
.ident = "Dell Inspiron 2",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
},
},
{
.ident = "Dell Latitude 2",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
},
},
{ /* UK Inspiron 6400 */
.ident = "Dell Inspiron 3",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MM061"),
},
},
{
.ident = "Dell Inspiron 3",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MP061"),
},
},
{
.ident = "Dell OptiPlex 7060",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "OptiPlex 7060"),
},
},
{
.ident = "Dell Precision",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Precision"),
},
},
{
.ident = "Dell Vostro",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"),
},
},
{
.ident = "Dell Studio",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Studio"),
},
},
{
.ident = "Dell XPS M140",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MXC051"),
},
},
{
.ident = "Dell XPS",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "XPS"),
},
},
{ }
};
MODULE_DEVICE_TABLE(dmi, i8k_dmi_table);
/*
* Only use for machines which need some special configuration
* in order to work correctly (e.g. if autoconfig fails on this machines).
*/
struct i8k_config_data {
uint fan_mult;
uint fan_max;
};
enum i8k_configs {
DELL_LATITUDE_D520,
DELL_PRECISION_490,
DELL_STUDIO,
DELL_XPS,
};
static const struct i8k_config_data i8k_config_data[] __initconst = {
[DELL_LATITUDE_D520] = {
.fan_mult = 1,
.fan_max = I8K_FAN_TURBO,
},
[DELL_PRECISION_490] = {
.fan_mult = 1,
.fan_max = I8K_FAN_TURBO,
},
[DELL_STUDIO] = {
.fan_mult = 1,
.fan_max = I8K_FAN_HIGH,
},
[DELL_XPS] = {
.fan_mult = 1,
.fan_max = I8K_FAN_HIGH,
},
};
static const struct dmi_system_id i8k_config_dmi_table[] __initconst = {
{
.ident = "Dell Latitude D520",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Latitude D520"),
},
.driver_data = (void *)&i8k_config_data[DELL_LATITUDE_D520],
},
{
.ident = "Dell Precision 490",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME,
"Precision WorkStation 490"),
},
.driver_data = (void *)&i8k_config_data[DELL_PRECISION_490],
},
{
.ident = "Dell Studio",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Studio"),
},
.driver_data = (void *)&i8k_config_data[DELL_STUDIO],
},
{
.ident = "Dell XPS M140",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MXC051"),
},
.driver_data = (void *)&i8k_config_data[DELL_XPS],
},
{ }
};
/*
* On some machines once I8K_SMM_GET_FAN_TYPE is issued then CPU fan speed
* randomly going up and down due to bug in Dell SMM or BIOS. Here is blacklist
* of affected Dell machines for which we disallow I8K_SMM_GET_FAN_TYPE call.
* See bug: https://bugzilla.kernel.org/show_bug.cgi?id=100121
*/
static const struct dmi_system_id i8k_blacklist_fan_type_dmi_table[] __initconst = {
{
.ident = "Dell Studio XPS 8000",
.matches = {
DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Studio XPS 8000"),
},
},
{
.ident = "Dell Studio XPS 8100",
.matches = {
DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Studio XPS 8100"),
},
},
{
.ident = "Dell Inspiron 580",
.matches = {
DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Inspiron 580 "),
},
},
{
.ident = "Dell Inspiron 3505",
.matches = {
DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Inspiron 3505"),
},
},
{ }
};
/*
* On some machines all fan related SMM functions implemented by Dell BIOS
* firmware freeze kernel for about 500ms. Until Dell fixes these problems fan
* support for affected blacklisted Dell machines stay disabled.
* See bug: https://bugzilla.kernel.org/show_bug.cgi?id=195751
*/
static const struct dmi_system_id i8k_blacklist_fan_support_dmi_table[] __initconst = {
{
.ident = "Dell Inspiron 7720",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Inspiron 7720"),
},
},
{
.ident = "Dell Vostro 3360",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Vostro 3360"),
},
},
{
.ident = "Dell XPS13 9333",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "XPS13 9333"),
},
},
{
.ident = "Dell XPS 15 L502X",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L502X"),
},
},
{ }
};
struct i8k_fan_control_data {
unsigned int manual_fan;
unsigned int auto_fan;
};
enum i8k_fan_controls {
I8K_FAN_30A3_31A3,
I8K_FAN_34A3_35A3,
};
static const struct i8k_fan_control_data i8k_fan_control_data[] __initconst = {
[I8K_FAN_30A3_31A3] = {
.manual_fan = 0x30a3,
.auto_fan = 0x31a3,
},
[I8K_FAN_34A3_35A3] = {
.manual_fan = 0x34a3,
.auto_fan = 0x35a3,
},
};
static const struct dmi_system_id i8k_whitelist_fan_control[] __initconst = {
{
.ident = "Dell Latitude 5480",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude 5480"),
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
},
{
.ident = "Dell Latitude E6440",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude E6440"),
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
},
{
.ident = "Dell Latitude E7440",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Latitude E7440"),
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
},
{
.ident = "Dell Precision 5530",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Precision 5530"),
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
},
{
.ident = "Dell Precision 7510",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Precision 7510"),
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
},
{
.ident = "Dell Precision 7540",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Precision 7540"),
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
},
{
.ident = "Dell XPS 13 7390",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "XPS 13 7390"),
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
},
{
.ident = "Dell Optiplex 7000",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "OptiPlex 7000"),
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_34A3_35A3],
},
{
.ident = "Dell XPS 9315",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "XPS 9315"),
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_30A3_31A3],
},
{
.ident = "Dell G15 5511",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Dell G15 5511"),
},
.driver_data = (void *)&i8k_fan_control_data[I8K_FAN_30A3_31A3],
},
{ }
};
/*
* Legacy SMM backend driver.
*/
static int __init dell_smm_probe(struct platform_device *pdev)
{
int ret;
ret = dell_smm_init_data(&pdev->dev, &i8k_smm_ops);
if (ret < 0)
return ret;
ret = dell_smm_init_hwmon(&pdev->dev);
if (ret)
return ret;
i8k_init_procfs(&pdev->dev);
return 0;
}
static struct platform_driver dell_smm_driver = {
.driver = {
.name = KBUILD_MODNAME,
},
};
static struct platform_device *dell_smm_device;
/*
* WMI SMM backend driver.
*/
static int dell_smm_wmi_probe(struct wmi_device *wdev, const void *context)
{
struct dell_smm_ops *ops;
int ret;
ops = devm_kzalloc(&wdev->dev, sizeof(*ops), GFP_KERNEL);
if (!ops)
return -ENOMEM;
ops->smm_call = wmi_smm_call;
ops->smm_dev = &wdev->dev;
if (dell_smm_get_signature(ops, I8K_SMM_GET_DELL_SIG1) &&
dell_smm_get_signature(ops, I8K_SMM_GET_DELL_SIG2))
return -ENODEV;
ret = dell_smm_init_data(&wdev->dev, ops);
if (ret < 0)
return ret;
return dell_smm_init_hwmon(&wdev->dev);
}
static const struct wmi_device_id dell_smm_wmi_id_table[] = {
{ DELL_SMM_WMI_GUID, NULL },
{ }
};
MODULE_DEVICE_TABLE(wmi, dell_smm_wmi_id_table);
static struct wmi_driver dell_smm_wmi_driver = {
.driver = {
.name = KBUILD_MODNAME,
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
.id_table = dell_smm_wmi_id_table,
.probe = dell_smm_wmi_probe,
.no_singleton = true,
};
/*
* Probe for the presence of a supported laptop.
*/
static void __init dell_smm_init_dmi(void)
{
struct i8k_fan_control_data *control;
struct i8k_config_data *config;
const struct dmi_system_id *id;
if (dmi_check_system(i8k_blacklist_fan_support_dmi_table)) {
if (!force) {
pr_notice("Disabling fan support due to BIOS bugs\n");
disallow_fan_support = true;
} else {
pr_warn("Enabling fan support despite BIOS bugs\n");
}
}
if (dmi_check_system(i8k_blacklist_fan_type_dmi_table)) {
if (!force) {
pr_notice("Disabling fan type call due to BIOS bugs\n");
disallow_fan_type_call = true;
} else {
pr_warn("Enabling fan type call despite BIOS bugs\n");
}
}
/*
* Set fan multiplier and maximal fan speed from DMI config.
* Values specified in module parameters override values from DMI.
*/
id = dmi_first_match(i8k_config_dmi_table);
if (id && id->driver_data) {
config = id->driver_data;
if (!fan_mult && config->fan_mult)
fan_mult = config->fan_mult;
if (!fan_max && config->fan_max)
fan_max = config->fan_max;
}
id = dmi_first_match(i8k_whitelist_fan_control);
if (id && id->driver_data) {
control = id->driver_data;
manual_fan = control->manual_fan;
auto_fan = control->auto_fan;
pr_info("Enabling support for setting automatic/manual fan control\n");
}
}
static int __init dell_smm_legacy_check(void)
{
if (!dmi_check_system(i8k_dmi_table)) {
if (!ignore_dmi && !force)
return -ENODEV;
pr_info("Probing for legacy SMM handler on unsupported machine\n");
pr_info("vendor=%s, model=%s, version=%s\n",
i8k_get_dmi_data(DMI_SYS_VENDOR),
i8k_get_dmi_data(DMI_PRODUCT_NAME),
i8k_get_dmi_data(DMI_BIOS_VERSION));
}
if (dell_smm_get_signature(&i8k_smm_ops, I8K_SMM_GET_DELL_SIG1) &&
dell_smm_get_signature(&i8k_smm_ops, I8K_SMM_GET_DELL_SIG2)) {
if (!force)
return -ENODEV;
pr_warn("Forcing legacy SMM calls on a possibly incompatible machine\n");
}
return 0;
}
static int __init i8k_init(void)
{
int ret;
dell_smm_init_dmi();
ret = dell_smm_legacy_check();
if (ret < 0) {
/*
* On modern machines, SMM communication happens over WMI, meaning
* the SMM handler might not react to legacy SMM calls.
*/
return wmi_driver_register(&dell_smm_wmi_driver);
}
dell_smm_device = platform_create_bundle(&dell_smm_driver, dell_smm_probe, NULL, 0, NULL,
0);
return PTR_ERR_OR_ZERO(dell_smm_device);
}
static void __exit i8k_exit(void)
{
if (dell_smm_device) {
platform_device_unregister(dell_smm_device);
platform_driver_unregister(&dell_smm_driver);
} else {
wmi_driver_unregister(&dell_smm_wmi_driver);
}
}
module_init(i8k_init);
module_exit(i8k_exit);