| 1 | /* |
| 2 | * i8k.c -- Linux driver for accessing the SMM BIOS on Dell laptops. |
| 3 | * See http://www.debian.org/~dz/i8k/ for more information |
| 4 | * and for latest version of this driver. |
| 5 | * |
| 6 | * Copyright (C) 2001 Massimo Dal Zotto <dz@debian.org> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify it |
| 9 | * under the terms of the GNU General Public License as published by the |
| 10 | * Free Software Foundation; either version 2, or (at your option) any |
| 11 | * later version. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, but |
| 14 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | * General Public License for more details. |
| 17 | */ |
| 18 | |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/types.h> |
| 21 | #include <linux/init.h> |
| 22 | #include <linux/proc_fs.h> |
| 23 | #include <linux/seq_file.h> |
| 24 | #include <linux/dmi.h> |
| 25 | #include <asm/uaccess.h> |
| 26 | #include <asm/io.h> |
| 27 | |
| 28 | #include <linux/i8k.h> |
| 29 | |
| 30 | #define I8K_VERSION "1.14 21/02/2005" |
| 31 | |
| 32 | #define I8K_SMM_FN_STATUS 0x0025 |
| 33 | #define I8K_SMM_POWER_STATUS 0x0069 |
| 34 | #define I8K_SMM_SET_FAN 0x01a3 |
| 35 | #define I8K_SMM_GET_FAN 0x00a3 |
| 36 | #define I8K_SMM_GET_SPEED 0x02a3 |
| 37 | #define I8K_SMM_GET_TEMP 0x10a3 |
| 38 | #define I8K_SMM_GET_DELL_SIG1 0xfea3 |
| 39 | #define I8K_SMM_GET_DELL_SIG2 0xffa3 |
| 40 | #define I8K_SMM_BIOS_VERSION 0x00a6 |
| 41 | |
| 42 | #define I8K_FAN_MULT 30 |
| 43 | #define I8K_MAX_TEMP 127 |
| 44 | |
| 45 | #define I8K_FN_NONE 0x00 |
| 46 | #define I8K_FN_UP 0x01 |
| 47 | #define I8K_FN_DOWN 0x02 |
| 48 | #define I8K_FN_MUTE 0x04 |
| 49 | #define I8K_FN_MASK 0x07 |
| 50 | #define I8K_FN_SHIFT 8 |
| 51 | |
| 52 | #define I8K_POWER_AC 0x05 |
| 53 | #define I8K_POWER_BATTERY 0x01 |
| 54 | |
| 55 | #define I8K_TEMPERATURE_BUG 1 |
| 56 | |
| 57 | static char bios_version[4]; |
| 58 | |
| 59 | MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)"); |
| 60 | MODULE_DESCRIPTION("Driver for accessing SMM BIOS on Dell laptops"); |
| 61 | MODULE_LICENSE("GPL"); |
| 62 | |
| 63 | static int force; |
| 64 | module_param(force, bool, 0); |
| 65 | MODULE_PARM_DESC(force, "Force loading without checking for supported models"); |
| 66 | |
| 67 | static int ignore_dmi; |
| 68 | module_param(ignore_dmi, bool, 0); |
| 69 | MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match"); |
| 70 | |
| 71 | static int restricted; |
| 72 | module_param(restricted, bool, 0); |
| 73 | MODULE_PARM_DESC(restricted, "Allow fan control if SYS_ADMIN capability set"); |
| 74 | |
| 75 | static int power_status; |
| 76 | module_param(power_status, bool, 0600); |
| 77 | MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k"); |
| 78 | |
| 79 | static int i8k_open_fs(struct inode *inode, struct file *file); |
| 80 | static int i8k_ioctl(struct inode *, struct file *, unsigned int, |
| 81 | unsigned long); |
| 82 | |
| 83 | static struct file_operations i8k_fops = { |
| 84 | .open = i8k_open_fs, |
| 85 | .read = seq_read, |
| 86 | .llseek = seq_lseek, |
| 87 | .release = single_release, |
| 88 | .ioctl = i8k_ioctl, |
| 89 | }; |
| 90 | |
| 91 | struct smm_regs { |
| 92 | unsigned int eax; |
| 93 | unsigned int ebx __attribute__ ((packed)); |
| 94 | unsigned int ecx __attribute__ ((packed)); |
| 95 | unsigned int edx __attribute__ ((packed)); |
| 96 | unsigned int esi __attribute__ ((packed)); |
| 97 | unsigned int edi __attribute__ ((packed)); |
| 98 | }; |
| 99 | |
| 100 | static inline char *i8k_get_dmi_data(int field) |
| 101 | { |
| 102 | return dmi_get_system_info(field) ? : "N/A"; |
| 103 | } |
| 104 | |
| 105 | /* |
| 106 | * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard. |
| 107 | */ |
| 108 | static int i8k_smm(struct smm_regs *regs) |
| 109 | { |
| 110 | int rc; |
| 111 | int eax = regs->eax; |
| 112 | |
| 113 | asm("pushl %%eax\n\t" |
| 114 | "movl 0(%%eax),%%edx\n\t" |
| 115 | "push %%edx\n\t" |
| 116 | "movl 4(%%eax),%%ebx\n\t" |
| 117 | "movl 8(%%eax),%%ecx\n\t" |
| 118 | "movl 12(%%eax),%%edx\n\t" |
| 119 | "movl 16(%%eax),%%esi\n\t" |
| 120 | "movl 20(%%eax),%%edi\n\t" |
| 121 | "popl %%eax\n\t" |
| 122 | "out %%al,$0xb2\n\t" |
| 123 | "out %%al,$0x84\n\t" |
| 124 | "xchgl %%eax,(%%esp)\n\t" |
| 125 | "movl %%ebx,4(%%eax)\n\t" |
| 126 | "movl %%ecx,8(%%eax)\n\t" |
| 127 | "movl %%edx,12(%%eax)\n\t" |
| 128 | "movl %%esi,16(%%eax)\n\t" |
| 129 | "movl %%edi,20(%%eax)\n\t" |
| 130 | "popl %%edx\n\t" |
| 131 | "movl %%edx,0(%%eax)\n\t" |
| 132 | "lahf\n\t" |
| 133 | "shrl $8,%%eax\n\t" |
| 134 | "andl $1,%%eax\n":"=a"(rc) |
| 135 | : "a"(regs) |
| 136 | : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory"); |
| 137 | |
| 138 | if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax) |
| 139 | return -EINVAL; |
| 140 | |
| 141 | return 0; |
| 142 | } |
| 143 | |
| 144 | /* |
| 145 | * Read the bios version. Return the version as an integer corresponding |
| 146 | * to the ascii value, for example "A17" is returned as 0x00413137. |
| 147 | */ |
| 148 | static int i8k_get_bios_version(void) |
| 149 | { |
| 150 | struct smm_regs regs = { .eax = I8K_SMM_BIOS_VERSION, }; |
| 151 | |
| 152 | return i8k_smm(®s) ? : regs.eax; |
| 153 | } |
| 154 | |
| 155 | /* |
| 156 | * Read the Fn key status. |
| 157 | */ |
| 158 | static int i8k_get_fn_status(void) |
| 159 | { |
| 160 | struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, }; |
| 161 | int rc; |
| 162 | |
| 163 | if ((rc = i8k_smm(®s)) < 0) |
| 164 | return rc; |
| 165 | |
| 166 | switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) { |
| 167 | case I8K_FN_UP: |
| 168 | return I8K_VOL_UP; |
| 169 | case I8K_FN_DOWN: |
| 170 | return I8K_VOL_DOWN; |
| 171 | case I8K_FN_MUTE: |
| 172 | return I8K_VOL_MUTE; |
| 173 | default: |
| 174 | return 0; |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | /* |
| 179 | * Read the power status. |
| 180 | */ |
| 181 | static int i8k_get_power_status(void) |
| 182 | { |
| 183 | struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, }; |
| 184 | int rc; |
| 185 | |
| 186 | if ((rc = i8k_smm(®s)) < 0) |
| 187 | return rc; |
| 188 | |
| 189 | return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY; |
| 190 | } |
| 191 | |
| 192 | /* |
| 193 | * Read the fan status. |
| 194 | */ |
| 195 | static int i8k_get_fan_status(int fan) |
| 196 | { |
| 197 | struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, }; |
| 198 | |
| 199 | regs.ebx = fan & 0xff; |
| 200 | return i8k_smm(®s) ? : regs.eax & 0xff; |
| 201 | } |
| 202 | |
| 203 | /* |
| 204 | * Read the fan speed in RPM. |
| 205 | */ |
| 206 | static int i8k_get_fan_speed(int fan) |
| 207 | { |
| 208 | struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, }; |
| 209 | |
| 210 | regs.ebx = fan & 0xff; |
| 211 | return i8k_smm(®s) ? : (regs.eax & 0xffff) * I8K_FAN_MULT; |
| 212 | } |
| 213 | |
| 214 | /* |
| 215 | * Set the fan speed (off, low, high). Returns the new fan status. |
| 216 | */ |
| 217 | static int i8k_set_fan(int fan, int speed) |
| 218 | { |
| 219 | struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, }; |
| 220 | |
| 221 | speed = (speed < 0) ? 0 : ((speed > I8K_FAN_MAX) ? I8K_FAN_MAX : speed); |
| 222 | regs.ebx = (fan & 0xff) | (speed << 8); |
| 223 | |
| 224 | return i8k_smm(®s) ? : i8k_get_fan_status(fan); |
| 225 | } |
| 226 | |
| 227 | /* |
| 228 | * Read the cpu temperature. |
| 229 | */ |
| 230 | static int i8k_get_temp(int sensor) |
| 231 | { |
| 232 | struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP, }; |
| 233 | int rc; |
| 234 | int temp; |
| 235 | |
| 236 | #ifdef I8K_TEMPERATURE_BUG |
| 237 | static int prev; |
| 238 | #endif |
| 239 | regs.ebx = sensor & 0xff; |
| 240 | if ((rc = i8k_smm(®s)) < 0) |
| 241 | return rc; |
| 242 | |
| 243 | temp = regs.eax & 0xff; |
| 244 | |
| 245 | #ifdef I8K_TEMPERATURE_BUG |
| 246 | /* |
| 247 | * Sometimes the temperature sensor returns 0x99, which is out of range. |
| 248 | * In this case we return (once) the previous cached value. For example: |
| 249 | # 1003655137 00000058 00005a4b |
| 250 | # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees |
| 251 | # 1003655139 00000054 00005c52 |
| 252 | */ |
| 253 | if (temp > I8K_MAX_TEMP) { |
| 254 | temp = prev; |
| 255 | prev = I8K_MAX_TEMP; |
| 256 | } else { |
| 257 | prev = temp; |
| 258 | } |
| 259 | #endif |
| 260 | |
| 261 | return temp; |
| 262 | } |
| 263 | |
| 264 | static int i8k_get_dell_signature(int req_fn) |
| 265 | { |
| 266 | struct smm_regs regs = { .eax = req_fn, }; |
| 267 | int rc; |
| 268 | |
| 269 | if ((rc = i8k_smm(®s)) < 0) |
| 270 | return rc; |
| 271 | |
| 272 | return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1; |
| 273 | } |
| 274 | |
| 275 | static int i8k_ioctl(struct inode *ip, struct file *fp, unsigned int cmd, |
| 276 | unsigned long arg) |
| 277 | { |
| 278 | int val = 0; |
| 279 | int speed; |
| 280 | unsigned char buff[16]; |
| 281 | int __user *argp = (int __user *)arg; |
| 282 | |
| 283 | if (!argp) |
| 284 | return -EINVAL; |
| 285 | |
| 286 | switch (cmd) { |
| 287 | case I8K_BIOS_VERSION: |
| 288 | val = i8k_get_bios_version(); |
| 289 | break; |
| 290 | |
| 291 | case I8K_MACHINE_ID: |
| 292 | memset(buff, 0, 16); |
| 293 | strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL), sizeof(buff)); |
| 294 | break; |
| 295 | |
| 296 | case I8K_FN_STATUS: |
| 297 | val = i8k_get_fn_status(); |
| 298 | break; |
| 299 | |
| 300 | case I8K_POWER_STATUS: |
| 301 | val = i8k_get_power_status(); |
| 302 | break; |
| 303 | |
| 304 | case I8K_GET_TEMP: |
| 305 | val = i8k_get_temp(0); |
| 306 | break; |
| 307 | |
| 308 | case I8K_GET_SPEED: |
| 309 | if (copy_from_user(&val, argp, sizeof(int))) |
| 310 | return -EFAULT; |
| 311 | |
| 312 | val = i8k_get_fan_speed(val); |
| 313 | break; |
| 314 | |
| 315 | case I8K_GET_FAN: |
| 316 | if (copy_from_user(&val, argp, sizeof(int))) |
| 317 | return -EFAULT; |
| 318 | |
| 319 | val = i8k_get_fan_status(val); |
| 320 | break; |
| 321 | |
| 322 | case I8K_SET_FAN: |
| 323 | if (restricted && !capable(CAP_SYS_ADMIN)) |
| 324 | return -EPERM; |
| 325 | |
| 326 | if (copy_from_user(&val, argp, sizeof(int))) |
| 327 | return -EFAULT; |
| 328 | |
| 329 | if (copy_from_user(&speed, argp + 1, sizeof(int))) |
| 330 | return -EFAULT; |
| 331 | |
| 332 | val = i8k_set_fan(val, speed); |
| 333 | break; |
| 334 | |
| 335 | default: |
| 336 | return -EINVAL; |
| 337 | } |
| 338 | |
| 339 | if (val < 0) |
| 340 | return val; |
| 341 | |
| 342 | switch (cmd) { |
| 343 | case I8K_BIOS_VERSION: |
| 344 | if (copy_to_user(argp, &val, 4)) |
| 345 | return -EFAULT; |
| 346 | |
| 347 | break; |
| 348 | case I8K_MACHINE_ID: |
| 349 | if (copy_to_user(argp, buff, 16)) |
| 350 | return -EFAULT; |
| 351 | |
| 352 | break; |
| 353 | default: |
| 354 | if (copy_to_user(argp, &val, sizeof(int))) |
| 355 | return -EFAULT; |
| 356 | |
| 357 | break; |
| 358 | } |
| 359 | |
| 360 | return 0; |
| 361 | } |
| 362 | |
| 363 | /* |
| 364 | * Print the information for /proc/i8k. |
| 365 | */ |
| 366 | static int i8k_proc_show(struct seq_file *seq, void *offset) |
| 367 | { |
| 368 | int fn_key, cpu_temp, ac_power; |
| 369 | int left_fan, right_fan, left_speed, right_speed; |
| 370 | |