drivers/char/toshiba.c

   1 /* toshiba.c -- Linux driver for accessing the SMM on Toshiba laptops
   2  *
   3  * Copyright (c) 1996-2001  Jonathan A. Buzzard (jonathan@buzzard.org.uk)
   4  *
   5  * Valuable assistance and patches from:
   6  *     Tom May <tom@you-bastards.com>
   7  *     Rob Napier <rnapier@employees.org>
   8  *
   9  * Fn status port numbers for machine ID's courtesy of
  10  *     0xfc02: Scott Eisert <scott.e@sky-eye.com>
  11  *     0xfc04: Steve VanDevender <stevev@efn.org>
  12  *     0xfc08: Garth Berry <garth@itsbruce.net>
  13  *     0xfc0a: Egbert Eich <eich@xfree86.org>
  14  *     0xfc10: Andrew Lofthouse <Andrew.Lofthouse@robins.af.mil>
  15  *     0xfc11: Spencer Olson <solson@novell.com>
  16  *     0xfc13: Claudius Frankewitz <kryp@gmx.de>
  17  *     0xfc15: Tom May <tom@you-bastards.com>
  18  *     0xfc17: Dave Konrad <konrad@xenia.it>
  19  *     0xfc1a: George Betzos <betzos@engr.colostate.edu>
  20  *     0xfc1b: Munemasa Wada <munemasa@jnovel.co.jp>
  21  *     0xfc1d: Arthur Liu <armie@slap.mine.nu>
  22  *     0xfc5a: Jacques L'helgoualc'h <lhh@free.fr>
  23  *     0xfcd1: Mr. Dave Konrad <konrad@xenia.it>
  24  *
  25  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
  26  *
  27  *   This code is covered by the GNU GPL and you are free to make any
  28  *   changes you wish to it under the terms of the license. However the
  29  *   code has the potential to render your computer and/or someone else's
  30  *   unusable. Please proceed with care when modifying the code.
  31  *
  32  * Note: Unfortunately the laptop hardware can close the System Configuration
  33  *       Interface on it's own accord. It is therefore necessary for *all*
  34  *       programs using this driver to be aware that *any* SCI call can fail at
  35  *       *any* time. It is up to any program to be aware of this eventuality
  36  *       and take appropriate steps.
  37  *
  38  * This program is free software; you can redistribute it and/or modify it
  39  * under the terms of the GNU General Public License as published by the
  40  * Free Software Foundation; either version 2, or (at your option) any
  41  * later version.
  42  *
  43  * This program is distributed in the hope that it will be useful, but
  44  * WITHOUT ANY WARRANTY; without even the implied warranty of
  45  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  46  * General Public License for more details.
  47  *
  48  * The information used to write this driver has been obtained by reverse
  49  * engineering the software supplied by Toshiba for their portable computers in
  50  * strict accordance with the European Council Directive 92/250/EEC on the legal
  51  * protection of computer programs, and it's implementation into English Law by
  52  * the Copyright (Computer Programs) Regulations 1992 (S.I. 1992 No.3233).
  53  *
  54  */
  55
  56 #define TOSH_VERSION "1.11 26/9/2001"
  57 #define TOSH_DEBUG 0
  58
  59 #include <linux/module.h>
  60 #include <linux/kernel.h>
  61 #include <linux/sched.h>
  62 #include <linux/types.h>
  63 #include <linux/fcntl.h>
  64 #include <linux/miscdevice.h>
  65 #include <linux/ioport.h>
  66 #include <asm/io.h>
  67 #include <asm/uaccess.h>
  68 #include <linux/init.h>
  69 #include <linux/stat.h>
  70 #include <linux/proc_fs.h>
  71
  72 #include <linux/toshiba.h>
  73
  74 #define TOSH_MINOR_DEV 181
  75
  76 MODULE_LICENSE("GPL");
  77 MODULE_AUTHOR("Jonathan Buzzard <jonathan@buzzard.org.uk>");
  78 MODULE_DESCRIPTION("Toshiba laptop SMM driver");
  79 MODULE_SUPPORTED_DEVICE("toshiba");
  80
  81 static int tosh_fn;
  82 module_param_named(fn, tosh_fn, int, 0);
  83 MODULE_PARM_DESC(fn, "User specified Fn key detection port");
  84
  85 static int tosh_id;
  86 static int tosh_bios;
  87 static int tosh_date;
  88 static int tosh_sci;
  89 static int tosh_fan;
  90
  91 static int tosh_ioctl(struct inode *, struct file *, unsigned int,
  92         unsigned long);
  93
  94
  95 static struct file_operations tosh_fops = {
  96         .owner          = THIS_MODULE,
  97         .ioctl          = tosh_ioctl,
  98 };
  99
 100 static struct miscdevice tosh_device = {
 101         TOSH_MINOR_DEV,
 102         "toshiba",
 103         &tosh_fops
 104 };
 105
 106 /*
 107  * Read the Fn key status
 108  */
 109 #ifdef CONFIG_PROC_FS
 110 static int tosh_fn_status(void)
 111 {
 112         unsigned char scan;
 113         unsigned long flags;
 114
 115         if (tosh_fn!=0) {
 116                 scan = inb(tosh_fn);
 117         } else {
 118                 local_irq_save(flags);
 119                 outb(0x8e, 0xe4);
 120                 scan = inb(0xe5);
 121                 local_irq_restore(flags);
 122         }
 123
 124         return (int) scan;
 125 }
 126 #endif
 127
 128
 129 /*
 130  * For the Portage 610CT and the Tecra 700CS/700CDT emulate the HCI fan function
 131  */
 132 static int tosh_emulate_fan(SMMRegisters *regs)
 133 {
 134         unsigned long eax,ecx,flags;
 135         unsigned char al;
 136
 137         eax = regs->eax & 0xff00;
 138         ecx = regs->ecx & 0xffff;
 139
 140         /* Portage 610CT */
 141
 142         if (tosh_id==0xfccb) {
 143                 if (eax==0xfe00) {
 144                         /* fan status */
 145                         local_irq_save(flags);
 146                         outb(0xbe, 0xe4);
 147                         al = inb(0xe5);
 148                         local_irq_restore(flags);
 149                         regs->eax = 0x00;
 150                         regs->ecx = (unsigned int) (al & 0x01);
 151                 }
 152                 if ((eax==0xff00) && (ecx==0x0000)) {
 153                         /* fan off */
 154                         local_irq_save(flags);
 155                         outb(0xbe, 0xe4);
 156                         al = inb(0xe5);
 157                         outb(0xbe, 0xe4);
 158                         outb (al | 0x01, 0xe5);
 159                         local_irq_restore(flags);
 160                         regs->eax = 0x00;
 161                         regs->ecx = 0x00;
 162                 }
 163                 if ((eax==0xff00) && (ecx==0x0001)) {
 164                         /* fan on */
 165                         local_irq_save(flags);
 166                         outb(0xbe, 0xe4);
 167                         al = inb(0xe5);
 168                         outb(0xbe, 0xe4);
 169                         outb(al & 0xfe, 0xe5);
 170                         local_irq_restore(flags);
 171                         regs->eax = 0x00;
 172                         regs->ecx = 0x01;
 173                 }
 174         }
 175
 176         /* Tecra 700CS/CDT */
 177
 178         if (tosh_id==0xfccc) {
 179                 if (eax==0xfe00) {
 180                         /* fan status */
 181                         local_irq_save(flags);
 182                         outb(0xe0, 0xe4);
 183                         al = inb(0xe5);
 184                         local_irq_restore(flags);
 185                         regs->eax = 0x00;
 186                         regs->ecx = al & 0x01;
 187                 }
 188                 if ((eax==0xff00) && (ecx==0x0000)) {
 189                         /* fan off */
 190                         local_irq_save(flags);
 191                         outb(0xe0, 0xe4);
 192                         al = inb(0xe5);
 193                         outw(0xe0 | ((al & 0xfe) << 8), 0xe4);
 194                         local_irq_restore(flags);
 195                         regs->eax = 0x00;
 196                         regs->ecx = 0x00;
 197                 }
 198                 if ((eax==0xff00) && (ecx==0x0001)) {
 199                         /* fan on */
 200                         local_irq_save(flags);
 201                         outb(0xe0, 0xe4);
 202                         al = inb(0xe5);
 203                         outw(0xe0 | ((al | 0x01) << 8), 0xe4);
 204                         local_irq_restore(flags);
 205                         regs->eax = 0x00;
 206                         regs->ecx = 0x01;
 207                 }
 208         }
 209
 210         return 0;
 211 }
 212
 213
 214 /*
 215  * Put the laptop into System Management Mode
 216  */
 217 int tosh_smm(SMMRegisters *regs)
 218 {
 219         int eax;
 220
 221         asm ("# load the values into the registers\n\t" \
 222                 "pushl %%eax\n\t" \
 223                 "movl 0(%%eax),%%edx\n\t" \
 224                 "push %%edx\n\t" \
 225                 "movl 4(%%eax),%%ebx\n\t" \
 226                 "movl 8(%%eax),%%ecx\n\t" \
 227                 "movl 12(%%eax),%%edx\n\t" \
 228                 "movl 16(%%eax),%%esi\n\t" \
 229                 "movl 20(%%eax),%%edi\n\t" \
 230                 "popl %%eax\n\t" \
 231                 "# call the System Management mode\n\t" \
 232                 "inb $0xb2,%%al\n\t"
 233                 "# fill out the memory with the values in the registers\n\t" \
 234                 "xchgl %%eax,(%%esp)\n\t"
 235                 "movl %%ebx,4(%%eax)\n\t" \
 236                 "movl %%ecx,8(%%eax)\n\t" \
 237                 "movl %%edx,12(%%eax)\n\t" \
 238                 "movl %%esi,16(%%eax)\n\t" \
 239                 "movl %%edi,20(%%eax)\n\t" \
 240                 "popl %%edx\n\t" \
 241                 "movl %%edx,0(%%eax)\n\t" \
 242                 "# setup the return value to the carry flag\n\t" \
 243                 "lahf\n\t" \
 244                 "shrl $8,%%eax\n\t" \
 245                 "andl $1,%%eax\n" \
 246                 : "=a" (eax)
 247                 : "a" (regs)
 248                 : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
 249
 250         return eax;
 251 }
 252
 253
 254 static int tosh_ioctl(struct inode *ip, struct file *fp, unsigned int cmd,
 255         unsigned long arg)
 256 {
 257         SMMRegisters regs;
 258         SMMRegisters __user *argp = (SMMRegisters __user *)arg;
 259         unsigned short ax,bx;
 260         int err;
 261
 262         if (!argp)
 263                 return -EINVAL;
 264
 265         if (copy_from_user(&regs, argp, sizeof(SMMRegisters)))
 266                 return -EFAULT;
 267
 268         switch (cmd) {
 269                 case TOSH_SMM:
 270                         ax = regs.eax & 0xff00;
 271                         bx = regs.ebx & 0xffff;
 272                         /* block HCI calls to read/write memory & PCI devices */
 273                         if (((ax==0xff00) || (ax==0xfe00)) && (bx>0x0069))
 274                                 return -EINVAL;
 275
 276                         /* do we need to emulate the fan ? */
 277                         if (tosh_fan==1) {
 278                                 if (((ax==0xf300) || (ax==0xf400)) && (bx==0x0004)) {
 279                                         err = tosh_emulate_fan(&regs);
 280                                         break;
 281                                 }
 282                         }
 283                         err = tosh_smm(&regs);
 284                         break;
 285                 default:
 286                         return -EINVAL;
 287         }
 288
 289         if (copy_to_user(argp, &regs, sizeof(SMMRegisters)))
 290                 return -EFAULT;
 291
 292         return (err==0) ? 0:-EINVAL;
 293 }
 294
 295
 296 /*
 297  * Print the information for /proc/toshiba
 298  */
 299 #ifdef CONFIG_PROC_FS
 300 static int tosh_get_info(char *buffer, char **start, off_t fpos, int length)
 301 {
 302         char *temp;
 303         int key;
 304
 305         temp = buffer;
 306         key = tosh_fn_status();
 307
 308         /* Arguments
 309              0) Linux driver version (this will change if format changes)
 310              1) Machine ID
 311              2) SCI version
 312              3) BIOS version (major, minor)
 313              4) BIOS date (in SCI date format)
 314              5) Fn Key status
 315         */
 316
 317         temp += sprintf(temp, "1.1 0x%04x %d.%d %d.%d 0x%04x 0x%02x\n",
 318                 tosh_id,
 319                 (tosh_sci & 0xff00)>>8,
 320                 tosh_sci & 0xff,
 321                 (tosh_bios & 0xff00)>>8,
 322                 tosh_bios & 0xff,
 323                 tosh_date,
 324                 key);
 325
 326         return temp-buffer;
 327 }
 328 #endif
 329
 330
 331 /*
 332  * Determine which port to use for the Fn key status
 333  */
 334 static void tosh_set_fn_port(void)
 335 {
 336         switch (tosh_id) {
 337                 case 0xfc02: case 0xfc04: case 0xfc09: case 0xfc0a: case 0xfc10:
 338                 case 0xfc11: case 0xfc13: case 0xfc15: case 0xfc1a: case 0xfc1b:
 339                 case 0xfc5a:
 340                         tosh_fn = 0x62;
 341                         break;
 342                 case 0xfc08: case 0xfc17: case 0xfc1d: case 0xfcd1: case 0xfce0:
 343                 case 0xfce2:
 344                         tosh_fn = 0x68;
 345                         break;
 346                 default:
 347                         tosh_fn = 0x00;
 348                         break;
 349         }
 350
 351         return;
 352 }
 353
 354
 355 /*
 356  * Get the machine identification number of the current model
 357  */
 358 static int tosh_get_machine_id(void __iomem *bios)
 359 {
 360         int id;
 361         SMMRegisters regs;
 362         unsigned short bx,cx;
 363         unsigned long address;
 364
 365         id = (0x100*(int) readb(bios+0xfffe))+((int) readb(bios+0xfffa));
 366
 367         /* do we have a SCTTable machine identication number on our hands */
 368
 369         if (id==0xfc2f) {
 370
 371                 /* start by getting a pointer into the BIOS */
 372
 373                 regs.eax = 0xc000;
 374                 regs.ebx = 0x0000;
 375                 regs.ecx = 0x0000;
 376                 tosh_smm(&regs);
 377                 bx = (unsigned short) (regs.ebx & 0xffff);
 378
 379                 /* At this point in the Toshiba routines under MS Windows
 380                    the bx register holds 0xe6f5. However my code is producing
 381                    a different value! For the time being I will just fudge the
 382                    value. This has been verified on a Satellite Pro 430CDT,
 383                    Tecra 750CDT, Tecra 780DVD and Satellite 310CDT. */
 384 #if TOSH_DEBUG
 385                 printk("toshiba: debugging ID ebx=0x%04x\n", regs.ebx);
 386 #endif
 387                 bx = 0xe6f5;
 388
 389                 /* now twiddle with our pointer a bit */
 390
 391                 address = bx;
 392                 cx = readw(bios + address);
 393                 address = 9+bx+cx;
 394                 cx = readw(bios + address);
 395                 address = 0xa+cx;
 396                 cx = readw(bios + address);
 397
 398                 /* now construct our machine identification number */
 399
 400                 id = ((cx & 0xff)<<8)+((cx & 0xff00)>>8);
 401         }
 402
 403         return id;
 404 }
 405
 406
 407 /*
 408  * Probe for the presence of a Toshiba laptop
 409  *
 410  *   returns and non-zero if unable to detect the presence of a Toshiba
 411  *   laptop, otherwise zero and determines the Machine ID, BIOS version and
 412  *   date, and SCI version.
 413  */
 414 static int tosh_probe(void)
 415 {
 416         int i,major,minor,day,year,month,flag;
 417         unsigned char signature[7] = { 0x54,0x4f,0x53,0x48,0x49,0x42,0x41 };
 418         SMMRegisters regs;
 419         void __iomem *bios = ioremap(0xf0000, 0x10000);
 420
 421         if (!bios)
 422                 return -ENOMEM;
 423
 424         /* extra sanity check for the string "TOSHIBA" in the BIOS because
 425            some machines that are not Toshiba's pass the next test */
 426
 427         for (i=0;i<7;i++) {
 428                 if (readb(bios+0xe010+i)!=signature[i]) {
 429                         printk("toshiba: not a supported Toshiba laptop\n");
 430                         iounmap(bios);
 431                         return -ENODEV;
 432                 }
 433         }
 434
 435         /* call the Toshiba SCI support check routine */
 436
 437         regs.eax = 0xf0f0;
 438         regs.ebx = 0x0000;
 439         regs.ecx = 0x0000;
 440         flag = tosh_smm(&regs);
 441
 442         /* if this is not a Toshiba laptop carry flag is set and ah=0x86 */
 443
 444         if ((flag==1) || ((regs.eax & 0xff00)==0x8600)) {
 445                 printk("toshiba: not a supported Toshiba laptop\n");
 446                 iounmap(bios);
 447                 return -ENODEV;
 448         }
 449
 450         /* if we get this far then we are running on a Toshiba (probably)! */
 451
 452         tosh_sci = regs.edx & 0xffff;
 453
 454         /* next get the machine ID of the current laptop */
 455
 456         tosh_id = tosh_get_machine_id(bios);
 457
 458         /* get the BIOS version */
 459
 460         major = readb(bios+0xe009)-'0';
 461         minor = ((readb(bios+0xe00b)-'0')*10)+(readb(bios+0xe00c)-'0');
 462         tosh_bios = (major*0x100)+minor;
 463
 464         /* get the BIOS date */
 465
 466         day = ((readb(bios+0xfff5)-'0')*10)+(readb(bios+0xfff6)-'0');
 467         month = ((readb(bios+0xfff8)-'0')*10)+(readb(bios+0xfff9)-'0');
 468         year = ((readb(bios+0xfffb)-'0')*10)+(readb(bios+0xfffc)-'0');
 469         tosh_date = (((year-90) & 0x1f)<<10) | ((month & 0xf)<<6)
 470                 | ((day & 0x1f)<<1);
 471
 472
 473         /* in theory we should check the ports we are going to use for the
 474            fn key detection (and the fan on the Portage 610/Tecra700), and
 475            then request them to stop other drivers using them. However as
 476            the keyboard driver grabs 0x60-0x6f and the pic driver grabs
 477            0xa0-0xbf we can't. We just have to live dangerously and use the
 478            ports anyway, oh boy! */
 479
 480         /* do we need to emulate the fan? */
 481
 482         if ((tosh_id==0xfccb) || (tosh_id==0xfccc))
 483                 tosh_fan = 1;
 484
 485         iounmap(bios);
 486
 487         return 0;
 488 }
 489
 490 static int __init toshiba_init(void)
 491 {
 492         int retval;
 493         /* are we running on a Toshiba laptop */
 494
 495         if (tosh_probe())
 496                 return -ENODEV;
 497
 498         printk(KERN_INFO "Toshiba System Managment Mode driver v" TOSH_VERSION "\n");
 499
 500         /* set the port to use for Fn status if not specified as a parameter */
 501         if (tosh_fn==0x00)
 502                 tosh_set_fn_port();
 503
 504         /* register the device file */
 505         retval = misc_register(&tosh_device);
 506         if (retval < 0)
 507                 return retval;
 508
 509 #ifdef CONFIG_PROC_FS
 510         /* register the proc entry */
 511         if (create_proc_info_entry("toshiba", 0, NULL, tosh_get_info) == NULL) {
 512                 misc_deregister(&tosh_device);
 513                 return -ENOMEM;
 514         }
 515 #endif
 516
 517         return 0;
 518 }
 519
 520 static void __exit toshiba_exit(void)
 521 {
 522         remove_proc_entry("toshiba", NULL);
 523         misc_deregister(&tosh_device);
 524 }
 525
 526 module_init(toshiba_init);
 527 module_exit(toshiba_exit);
 528