/* * 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 * * 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 #include #include #include #include #include #include #include #include #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 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 i8k_open_fs(struct inode *inode, struct file *file); static int i8k_ioctl(struct inode *, struct file *, unsigned int, unsigned long); static const struct file_operations i8k_fops = { .open = i8k_open_fs, .read = seq_read, .llseek = seq_lseek, .release = single_release, .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 char *i8k_get_dmi_data(int field) { 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; asm("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"); 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) * I8K_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(struct inode *ip, 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; } /* * 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"), }, }, { } }; /* * 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 = create_proc_entry("i8k", 0, NULL); if (!proc_i8k) return -ENOENT; proc_i8k->proc_fops = &i8k_fops; proc_i8k->owner = THIS_MODULE; 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);