/*
* i8k.c -- Linux driver for accessing the SMM BIOS on Dell laptops.
* See http://www.debian.org/~dz/i8k/ for more information
* and for latest version of this driver.
*
* Copyright (C) 2001 Massimo Dal Zotto <dz@debian.org>
*
* 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, 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.
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/dmi.h>
#include <linux/capability.h>
#include <linux/mutex.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <linux/i8k.h>
#define I8K_VERSION "1.14 21/02/2005"
#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_TEMP 0x10a3
#define I8K_SMM_GET_DELL_SIG1 0xfea3
#define I8K_SMM_GET_DELL_SIG2 0xffa3
#define I8K_SMM_BIOS_VERSION 0x00a6
#define I8K_FAN_MULT 30
#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 I8K_TEMPERATURE_BUG 1
static DEFINE_MUTEX(i8k_mutex);
static char bios_version[4];
MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
MODULE_DESCRIPTION("Driver for accessing SMM BIOS on Dell laptops");
MODULE_LICENSE("GPL");
static int force;
module_param(force, bool, 0);
MODULE_PARM_DESC(force, "Force loading without checking for supported models");
static int ignore_dmi;
module_param(ignore_dmi, bool, 0);
MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
static int restricted;
module_param(restricted, bool, 0);
MODULE_PARM_DESC(restricted, "Allow fan control if SYS_ADMIN capability set");
static int power_status;
module_param(power_status, bool, 0600);
MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k");
static int fan_mult = I8K_FAN_MULT;
module_param(fan_mult, int, 0);
MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with");
static int i8k_open_fs(struct inode *inode, struct file *file);
static long i8k_ioctl(struct file *, unsigned int, unsigned long);
static const struct file_operations i8k_fops = {
.owner = THIS_MODULE,
.open = i8k_open_fs,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
.unlocked_ioctl = i8k_ioctl,
};
struct smm_regs {
unsigned int eax;
unsigned int ebx __attribute__ ((packed));
unsigned int ecx __attribute__ ((packed));
unsigned int edx __attribute__ ((packed));
unsigned int esi __attribute__ ((packed));
unsigned int edi __attribute__ ((packed));
};
static inline const char *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(struct smm_regs *regs)
{
int rc;
int eax = regs->eax;
#if defined(CONFIG_X86_64)
asm volatile("pushq %%rax\n\t"
"movl 0(%%rax),%%edx\n\t"
"pushq %%rdx\n\t"
"movl 4(%%rax),%%ebx\n\t"
"movl 8(%%rax),%%ecx\n\t"
"movl 12(%%rax),%%edx\n\t"
"movl 16(%%rax),%%esi\n\t"
"movl 20(%%rax),%%edi\n\t"
"popq %%rax\n\t"
"out %%al,$0xb2\n\t"
"out %%al,$0x84\n\t"
"xchgq %%rax,(%%rsp)\n\t"
"movl %%ebx,4(%%rax)\n\t"
"movl %%ecx,8(%%rax)\n\t"
"movl %%edx,12(%%rax)\n\t"
"movl %%esi,16(%%rax)\n\t"
"movl %%edi,20(%%rax)\n\t"
"popq %%rdx\n\t"
"movl %%edx,0(%%rax)\n\t"
"pushfq\n\t"
"popq %%rax\n\t"
"andl $1,%%eax\n"
:"=a"(rc)
: "a"(regs)
: "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
#else
asm volatile("pushl %%eax\n\t"
"movl 0(%%eax),%%edx\n\t"
"push %%edx\n\t"
"movl 4(%%eax),%%ebx\n\t"
"movl 8(%%eax),%%ecx\n\t"
"movl 12(%%eax),%%edx\n\t"
"movl 16(%%eax),%%esi\n\t"
"movl 20(%%eax),%%edi\n\t"
"popl %%eax\n\t"
"out %%al,$0xb2\n\t"
"out %%al,$0x84\n\t"
"xchgl %%eax,(%%esp)\n\t"
"movl %%ebx,4(%%eax)\n\t"
"movl %%ecx,8(%%eax)\n\t"
"movl %%edx,12(%%eax)\n\t"
"movl %%esi,16(%%eax)\n\t"
"movl %%edi,20(%%eax)\n\t"
"popl %%edx\n\t"
"movl %%edx,0(%%eax)\n\t"
"lahf\n\t"
"shrl $8,%%eax\n\t"
"andl $1,%%eax\n"
:"=a"(rc)
: "a"(regs)
: "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
#endif
if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
return -EINVAL;
return 0;
}
/*
* Read the bios version. Return the version as an integer corresponding
* to the ascii value, for example "A17" is returned as 0x00413137.
*/
static int i8k_get_bios_version(void)
{
struct smm_regs regs = { .eax = I8K_SMM_BIOS_VERSION, };
return i8k_smm(®s) ? : regs.eax;
}
/*
* Read the Fn key status.
*/
static int i8k_get_fn_status(void)
{
struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, };
int rc;
if ((rc = i8k_smm(®s)) < 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(void)
{
struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, };
int rc;
if ((rc = i8k_smm(®s)) < 0)
return rc;
return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY;
}
/*
* Read the fan status.
*/
static int i8k_get_fan_status(int fan)
{
struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, };
regs.ebx = fan & 0xff;
return i8k_smm(®s) ? : regs.eax & 0xff;
}
/*
* Read the fan speed in RPM.
*/
static int i8k_get_fan_speed(int fan)
{
struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, };
regs.ebx = fan & 0xff;
return i8k_smm(®s) ? : (regs.eax & 0xffff) * fan_mult;
}
/*
* Set the fan speed (off, low, high). Returns the new fan status.
*/
static int i8k_set_fan(int fan, int speed)
{
struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
speed = (speed < 0) ? 0 : ((speed > I8K_FAN_MAX) ? I8K_FAN_MAX : speed);
regs.ebx = (fan & 0xff) | (speed << 8);
return i8k_smm(®s) ? : i8k_get_fan_status(fan);
}
/*
* Read the cpu temperature.
*/
static int i8k_get_temp(int sensor)
{
struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP, };
int rc;
int temp;
#ifdef I8K_TEMPERATURE_BUG
static int prev;
#endif
regs.ebx = sensor & 0xff;
if ((rc = i8k_smm(®s)) < 0)
return rc;
temp = regs.eax & 0xff;
#ifdef I8K_TEMPERATURE_BUG
/*
* Sometimes the temperature sensor returns 0x99, which is out of range.
* In this case we return (once) the previous cached value. For example:
# 1003655137 00000058 00005a4b
# 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
# 1003655139 00000054 00005c52
*/
if (temp > I8K_MAX_TEMP) {
temp = prev;
prev = I8K_MAX_TEMP;
} else {
prev = temp;
}
#endif
return temp;
}
static int i8k_get_dell_signature(int req_fn)
{
struct smm_regs regs = { .eax = req_fn, };
int rc;
if ((rc = i8k_smm(®s)) < 0)
return rc;
return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
}
static int
i8k_ioctl_unlocked(struct file *fp, unsigned int cmd, unsigned long arg)
{
int val = 0;
int speed;
unsigned char buff[16];
int __user *argp = (int __user *)arg;
if (!argp)
return -EINVAL;
switch (cmd) {
case I8K_BIOS_VERSION:
val = i8k_get_bios_version();
break;
case I8K_MACHINE_ID:
memset(buff, 0, 16);
strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL), sizeof(buff));
break;
case I8K_FN_STATUS:
val = i8k_get_fn_status();
break;
case I8K_POWER_STATUS:
val = i8k_get_power_status();
break;
case I8K_GET_TEMP:
val = i8k_get_temp(0);
break;
case I8K_GET_SPEED:
if (copy_from_user(&val, argp, sizeof(int)))
return -EFAULT;
val = i8k_get_fan_speed(val);
break;
case I8K_GET_FAN:
if (copy_from_user(&val, argp, sizeof(int)))
return -EFAULT;
val = i8k_get_fan_status(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 (copy_from_user(&speed, argp + 1, sizeof(int)))
return -EFAULT;
val = i8k_set_fan(val, speed);
break;
default:
return -EINVAL;
}
if (val < 0)
return val;
switch (cmd) {
case I8K_BIOS_VERSION:
if (copy_to_user(argp, &val, 4))
return -EFAULT;
break;
case I8K_MACHINE_ID:
if (copy_to_user(argp, buff, 16))
return -EFAULT;
break;
default:
if (copy_to_user(argp, &val, sizeof(int)))
return -EFAULT;
break;
}
return 0;
}
static long i8k_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
{
long ret;
mutex_lock(&i8k_mutex);
ret = i8k_ioctl_unlocked(fp, cmd, arg);
mutex_unlock(&i8k_mutex);
return ret;
}
/*
* Print the information for /proc/i8k.
*/
static int i8k_proc_show(struct seq_file *seq, void *offset)
{
int fn_key, cpu_temp, ac_power;
int left_fan, right_fan, left_speed, right_speed;
cpu_temp = i8k_get_temp(0); /* 11100 µs */
left_fan = i8k_get_fan_status(I8K_FAN_LEFT); /* 580 µs */
right_fan = i8k_get_fan_status(I8K_FAN_RIGHT); /* 580 µs */
left_speed = i8k_get_fan_speed(I8K_FAN_LEFT); /* 580 µs */
right_speed = i8k_get_fan_speed(I8K_FAN_RIGHT); /* 580 µs */
fn_key = i8k_get_fn_status(); /* 750 µs */
if (power_status)
ac_power = i8k_get_power_status(); /* 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
*/
return seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
I8K_PROC_FMT,
bios_version,
i8k_get_dmi_data(DMI_PRODUCT_SERIAL),
cpu_temp,
left_fan, right_fan, left_speed, right_speed,
ac_power, fn_key);
}
static int i8k_open_fs(struct inode *inode, struct file *file)
{
return single_open(file, i8k_proc_show, NULL);
}
static struct dmi_system_id __initdata i8k_dmi_table[] = {
{
.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 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"),
},
},
{ }
};
/*
* Probe for the presence of a supported laptop.
*/
static int __init i8k_probe(void)
{
char buff[4];
int version;
/*
* Get DMI information
*/
if (!dmi_check_system(i8k_dmi_table)) {
if (!ignore_dmi && !force)
return -ENODEV;
printk(KERN_INFO "i8k: not running on a supported Dell system.\n");
printk(KERN_INFO "i8k: 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));
}
strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION), sizeof(bios_version));
/*
* Get SMM Dell signature
*/
if (i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG1) &&
i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) {
printk(KERN_ERR "i8k: unable to get SMM Dell signature\n");
if (!force)
return -ENODEV;
}
/*
* Get SMM BIOS version.
*/
version = i8k_get_bios_version();
if (version <= 0) {
printk(KERN_WARNING "i8k: unable to get SMM BIOS version\n");
} else {
buff[0] = (version >> 16) & 0xff;
buff[1] = (version >> 8) & 0xff;
buff[2] = (version) & 0xff;
buff[3] = '\0';
/*
* If DMI BIOS version is unknown use SMM BIOS version.
*/
if (!dmi_get_system_info(DMI_BIOS_VERSION))
strlcpy(bios_version, buff, sizeof(bios_version));
/*
* Check if the two versions match.
*/
if (strncmp(buff, bios_version, sizeof(bios_version)) != 0)
printk(KERN_WARNING "i8k: BIOS version mismatch: %s != %s\n",
buff, bios_version);
}
return 0;
}
static int __init i8k_init(void)
{
struct proc_dir_entry *proc_i8k;
/* Are we running on an supported laptop? */
if (i8k_probe())
return -ENODEV;
/* Register the proc entry */
proc_i8k = proc_create("i8k", 0, NULL, &i8k_fops);
if (!proc_i8k)
return -ENOENT;
printk(KERN_INFO
"Dell laptop SMM driver v%s Massimo Dal Zotto (dz@debian.org)\n",
I8K_VERSION);
return 0;
}
static void __exit i8k_exit(void)
{
remove_proc_entry("i8k", NULL);
}
module_init(i8k_init);
module_exit(i8k_exit);