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/types.h>
  62 #include <linux/fcntl.h>
  63 #include <linux/miscdevice.h>
  64 #include <linux/ioport.h>
  65 #include <asm/io.h>
  66 #include <asm/uaccess.h>
  67 #include <linux/init.h>
  68 #include <linux/stat.h>
  69 #include <linux/proc_fs.h>
  70 #include <linux/seq_file.h>
  71 #include <linux/mutex.h>
  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 DEFINE_MUTEX(tosh_mutex);
  82 static int tosh_fn;
  83 module_param_named(fn, tosh_fn, int, 0);
  84 MODULE_PARM_DESC(fn, "User specified Fn key detection port");
  85
  86 static int tosh_id;
  87 static int tosh_bios;
  88 static int tosh_date;
  89 static int tosh_sci;
  90 static int tosh_fan;
  91
  92 static long tosh_ioctl(struct file *, unsigned int,
  93         unsigned long);
  94
  95
  96 static const struct file_operations tosh_fops = {
  97         .owner          = THIS_MODULE,
  98         .unlocked_ioctl = tosh_ioctl,
  99 };
 100
 101 static struct miscdevice tosh_device = {
 102         TOSH_MINOR_DEV,
 103         "toshiba",
 104         &tosh_fops
 105 };
 106
 107 /*
 108  * Read the Fn key status
 109  */
 110 #ifdef CONFIG_PROC_FS
 111 static int tosh_fn_status(void)
 112 {
 113         unsigned char scan;
 114         unsigned long flags;
 115
 116         if (tosh_fn!=0) {
 117                 scan = inb(tosh_fn);
 118         } else {
 119                 local_irq_save(flags);
 120                 outb(0x8e, 0xe4);
 121                 scan = inb(0xe5);
 122                 local_irq_restore(flags);
 123         }
 124
 125         return (int) scan;
 126 }
 127 #endif
 128
 129
 130 /*
 131  * For the Portage 610CT and the Tecra 700CS/700CDT emulate the HCI fan function
 132  */
 133 static int tosh_emulate_fan(SMMRegisters *regs)
 134 {
 135         unsigned long eax,ecx,flags;
 136         unsigned char al;
 137
 138         eax = regs->eax & 0xff00;
 139         ecx = regs->ecx & 0xffff;
 140
 141         /* Portage 610CT */
 142
 143         if (tosh_id==0xfccb) {
 144                 if (eax==0xfe00) {
 145                         /* fan status */
 146                         local_irq_save(flags);
 147                         outb(0xbe, 0xe4);
 148                         al = inb(0xe5);
 149                         local_irq_restore(flags);
 150                         regs->eax = 0x00;
 151                         regs->ecx = (unsigned int) (al & 0x01);
 152                 }
 153                 if ((eax==0xff00) && (ecx==0x0000)) {
 154                         /* fan off */
 155                         local_irq_save(flags);
 156                         outb(0xbe, 0xe4);
 157                         al = inb(0xe5);
 158                         outb(0xbe, 0xe4);
 159                         outb (al | 0x01, 0xe5);
 160                         local_irq_restore(flags);
 161                         regs->eax = 0x00;
 162                         regs->ecx = 0x00;
 163                 }
 164                 if ((eax==0xff00) && (ecx==0x0001)) {
 165                         /* fan on */
 166                         local_irq_save(flags);
 167                         outb(0xbe, 0xe4);
 168                         al = inb(0xe5);
 169                         outb(0xbe, 0xe4);
 170                         outb(al & 0xfe, 0xe5);
 171                         local_irq_restore(flags);
 172                         regs->eax = 0x00;
 173                         regs->ecx = 0x01;
 174                 }
 175         }
 176
 177         /* Tecra 700CS/CDT */
 178
 179         if (tosh_id==0xfccc) {
 180                 if (eax==0xfe00) {
 181                         /* fan status */
 182                         local_irq_save(flags);
 183                         outb(0xe0, 0xe4);
 184                         al = inb(0xe5);
 185                         local_irq_restore(flags);
 186                         regs->eax = 0x00;
 187                         regs->ecx = al & 0x01;
 188                 }
 189                 if ((eax==0xff00) && (ecx==0x0000)) {
 190                         /* fan off */
 191                         local_irq_save(flags);
 192                         outb(0xe0, 0xe4);
 193                         al = inb(0xe5);
 194                         outw(0xe0 | ((al & 0xfe) << 8), 0xe4);
 195                         local_irq_restore(flags);
 196                         regs->eax = 0x00;
 197                         regs->ecx = 0x00;
 198                 }
 199                 if ((eax==0xff00) && (ecx==0x0001)) {
 200                         /* fan on */
 201                         local_irq_save(flags);
 202                         outb(0xe0, 0xe4);
 203                         al = inb(0xe5);
 204                         outw(0xe0 | ((al | 0x01) << 8), 0xe4);
 205                         local_irq_restore(flags);
 206                         regs->eax = 0x00;
 207                         regs->ecx = 0x01;
 208                 }
 209         }
 210
 211         return 0;
 212 }
 213
 214
 215 /*
 216  * Put the laptop into System Management Mode
 217  */
 218 int tosh_smm(SMMRegisters *regs)
 219 {
 220         int eax;
 221
 222         asm ("# load the values into the registers\n\t" \
 223                 "pushl %%eax\n\t" \
 224                 "movl 0(%%eax),%%edx\n\t" \
 225                 "push %%edx\n\t" \
 226                 "movl 4(%%eax),%%ebx\n\t" \
 227                 "movl 8(%%eax),%%ecx\n\t" \
 228                 "movl 12(%%eax),%%edx\n\t" \
 229                 "movl 16(%%eax),%%esi\n\t" \
 230                 "movl 20(%%eax),%%edi\n\t" \
 231                 "popl %%eax\n\t" \
 232                 "# call the System Management mode\n\t" \
 233                 "inb $0xb2,%%al\n\t"
 234                 "# fill out the memory with the values in the registers\n\t" \
 235                 "xchgl %%eax,(%%esp)\n\t"
 236                 "movl %%ebx,4(%%eax)\n\t" \
 237                 "movl %%ecx,8(%%eax)\n\t" \
 238                 "movl %%edx,12(%%eax)\n\t" \
 239                 "movl %%esi,16(%%eax)\n\t" \
 240                 "movl %%edi,20(%%eax)\n\t" \
 241                 "popl %%edx\n\t" \
 242                 "movl %%edx,0(%%eax)\n\t" \
 243                 "# setup the return value to the carry flag\n\t" \
 244                 "lahf\n\t" \
 245                 "shrl $8,%%eax\n\t" \
 246                 "andl $1,%%eax\n" \
 247                 : "=a" (eax)
 248                 : "a" (regs)
 249                 : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
 250
 251         return eax;
 252 }
 253 EXPORT_SYMBOL(tosh_smm);
 254
 255
 256 static long tosh_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
 257 {
 258         SMMRegisters regs;
 259         SMMRegisters __user *argp = (SMMRegisters __user *)arg;
 260         unsigned short ax,bx;
 261         int err;
 262
 263         if (!argp)
 264                 return -EINVAL;
 265
 266         if (copy_from_user(&regs, argp, sizeof(SMMRegisters)))
 267                 return -EFAULT;
 268
 269         switch (cmd) {
 270                 case TOSH_SMM:
 271                         ax = regs.eax & 0xff00;
 272                         bx = regs.ebx & 0xffff;
 273                         /* block HCI calls to read/write memory & PCI devices */
 274                         if (((ax==0xff00) || (ax==0xfe00)) && (bx>0x0069))
 275                                 return -EINVAL;
 276
 277                         /* do we need to emulate the fan ? */
 278                         mutex_lock(&tosh_mutex);
 279                         if (tosh_fan==1) {
 280                                 if (((ax==0xf300) || (ax==0xf400)) && (bx==0x0004)) {
 281                                         err = tosh_emulate_fan(&regs);
 282                                         mutex_unlock(&tosh_mutex);
 283                                         break;
 284                                 }
 285                         }
 286                         err = tosh_smm(&regs);
 287                         mutex_unlock(&tosh_mutex);
 288                         break;
 289                 default:
 290                         return -EINVAL;
 291         }
 292
 293         if (copy_to_user(argp, &regs, sizeof(SMMRegisters)))
 294                 return -EFAULT;
 295
 296         return (err==0) ? 0:-EINVAL;
 297 }
 298
 299
 300 /*
 301  * Print the information for /proc/toshiba
 302  */
 303 #ifdef CONFIG_PROC_FS
 304 static int proc_toshiba_show(struct seq_file *m, void *v)
 305 {
 306         int key;
 307
 308         key = tosh_fn_status();
 309
 310         /* Arguments
 311              0) Linux driver version (this will change if format changes)
 312              1) Machine ID
 313              2) SCI version
 314              3) BIOS version (major, minor)
 315              4) BIOS date (in SCI date format)
 316              5) Fn Key status
 317         */
 318         seq_printf(m, "1.1 0x%04x %d.%d %d.%d 0x%04x 0x%02x\n",
 319                 tosh_id,
 320                 (tosh_sci & 0xff00)>>8,
 321                 tosh_sci & 0xff,
 322                 (tosh_bios & 0xff00)>>8,
 323                 tosh_bios & 0xff,
 324                 tosh_date,
 325                 key);
 326         return 0;
 327 }
 328
 329 static int proc_toshiba_open(struct inode *inode, struct file *file)
 330 {
 331         return single_open(file, proc_toshiba_show, NULL);
 332 }
 333
 334 static const struct file_operations proc_toshiba_fops = {
 335         .owner          = THIS_MODULE,
 336         .open           = proc_toshiba_open,
 337         .read           = seq_read,
 338         .llseek         = seq_lseek,
 339         .release        = single_release,
 340 };
 341 #endif
 342
 343
 344 /*
 345  * Determine which port to use for the Fn key status
 346  */
 347 static void tosh_set_fn_port(void)
 348 {
 349         switch (tosh_id) {
 350                 case 0xfc02: case 0xfc04: case 0xfc09: case 0xfc0a: case 0xfc10:
 351                 case 0xfc11: case 0xfc13: case 0xfc15: case 0xfc1a: case 0xfc1b:
 352                 case 0xfc5a:
 353                         tosh_fn = 0x62;
 354                         break;
 355                 case 0xfc08: case 0xfc17: case 0xfc1d: case 0xfcd1: case 0xfce0:
 356                 case 0xfce2:
 357                         tosh_fn = 0x68;
 358                         break;
 359                 default:
 360                         tosh_fn = 0x00;
 361                         break;
 362         }
 363
 364         return;
 365 }
 366
 367
 368 /*
 369  * Get the machine identification number of the current model
 370  */
 371 static int tosh_get_machine_id(void __iomem *bios)
 372 {
 373         int id;
 374         SMMRegisters regs;
 375         unsigned short bx,cx;
 376         unsigned long address;
 377
 378         id = (0x100*(int) readb(bios+0xfffe))+((int) readb(bios+0xfffa));
 379
 380         /* do we have a SCTTable machine identication number on our hands */
 381
 382         if (id==0xfc2f) {
 383
 384                 /* start by getting a pointer into the BIOS */
 385
 386                 regs.eax = 0xc000;
 387                 regs.ebx = 0x0000;
 388                 regs.ecx = 0x0000;
 389                 tosh_smm(&regs);
 390                 bx = (unsigned short) (regs.ebx & 0xffff);
 391
 392                 /* At this point in the Toshiba routines under MS Windows
 393                    the bx register holds 0xe6f5. However my code is producing
 394                    a different value! For the time being I will just fudge the
 395                    value. This has been verified on a Satellite Pro 430CDT,
 396                    Tecra 750CDT, Tecra 780DVD and Satellite 310CDT. */
 397 #if TOSH_DEBUG
 398                 printk("toshiba: debugging ID ebx=0x%04x\n", regs.ebx);
 399 #endif
 400                 bx = 0xe6f5;
 401
 402                 /* now twiddle with our pointer a bit */
 403
 404                 address = bx;
 405                 cx = readw(bios + address);
 406                 address = 9+bx+cx;
 407                 cx = readw(bios + address);
 408                 address = 0xa+cx;
 409                 cx = readw(bios + address);
 410
 411                 /* now construct our machine identification number */
 412
 413                 id = ((cx & 0xff)<<8)+((cx & 0xff00)>>8);
 414         }
 415
 416         return id;
 417 }
 418
 419
 420 /*
 421  * Probe for the presence of a Toshiba laptop
 422  *
 423  *   returns and non-zero if unable to detect the presence of a Toshiba
 424  *   laptop, otherwise zero and determines the Machine ID, BIOS version and
 425  *   date, and SCI version.
 426  */
 427 static int tosh_probe(void)
 428 {
 429         int i,major,minor,day,year,month,flag;
 430         unsigned char signature[7] = { 0x54,0x4f,0x53,0x48,0x49,0x42,0x41 };
 431         SMMRegisters regs;
 432         void __iomem *bios = ioremap_cache(0xf0000, 0x10000);
 433
 434         if (!bios)
 435                 return -ENOMEM;
 436
 437         /* extra sanity check for the string "TOSHIBA" in the BIOS because
 438            some machines that are not Toshiba's pass the next test */
 439
 440         for (i=0;i<7;i++) {
 441                 if (readb(bios+0xe010+i)!=signature[i]) {
 442                         printk("toshiba: not a supported Toshiba laptop\n");
 443                         iounmap(bios);
 444                         return -ENODEV;
 445                 }
 446         }
 447
 448         /* call the Toshiba SCI support check routine */
 449
 450         regs.eax = 0xf0f0;
 451         regs.ebx = 0x0000;
 452         regs.ecx = 0x0000;
 453         flag = tosh_smm(&regs);
 454
 455         /* if this is not a Toshiba laptop carry flag is set and ah=0x86 */
 456
 457         if ((flag==1) || ((regs.eax & 0xff00)==0x8600)) {
 458                 printk("toshiba: not a supported Toshiba laptop\n");
 459                 iounmap(bios);
 460                 return -ENODEV;
 461         }
 462
 463         /* if we get this far then we are running on a Toshiba (probably)! */
 464
 465         tosh_sci = regs.edx & 0xffff;
 466
 467         /* next get the machine ID of the current laptop */
 468
 469         tosh_id = tosh_get_machine_id(bios);
 470
 471         /* get the BIOS version */
 472
 473         major = readb(bios+0xe009)-'0';
 474         minor = ((readb(bios+0xe00b)-'0')*10)+(readb(bios+0xe00c)-'0');
 475         tosh_bios = (major*0x100)+minor;
 476
 477         /* get the BIOS date */
 478
 479         day = ((readb(bios+0xfff5)-'0')*10)+(readb(bios+0xfff6)-'0');
 480         month = ((readb(bios+0xfff8)-'0')*10)+(readb(bios+0xfff9)-'0');
 481         year = ((readb(bios+0xfffb)-'0')*10)+(readb(bios+0xfffc)-'0');
 482         tosh_date = (((year-90) & 0x1f)<<10) | ((month & 0xf)<<6)
 483                 | ((day & 0x1f)<<1);
 484
 485
 486         /* in theory we should check the ports we are going to use for the
 487            fn key detection (and the fan on the Portage 610/Tecra700), and
 488            then request them to stop other drivers using them. However as
 489            the keyboard driver grabs 0x60-0x6f and the pic driver grabs
 490            0xa0-0xbf we can't. We just have to live dangerously and use the
 491            ports anyway, oh boy! */
 492
 493         /* do we need to emulate the fan? */
 494
 495         if ((tosh_id==0xfccb) || (tosh_id==0xfccc))
 496                 tosh_fan = 1;
 497
 498         iounmap(bios);
 499
 500         return 0;
 501 }
 502
 503 static int __init toshiba_init(void)
 504 {
 505         int retval;
 506         /* are we running on a Toshiba laptop */
 507
 508         if (tosh_probe())
 509                 return -ENODEV;
 510
 511         printk(KERN_INFO "Toshiba System Management Mode driver v" TOSH_VERSION "\n");
 512
 513         /* set the port to use for Fn status if not specified as a parameter */
 514         if (tosh_fn==0x00)
 515                 tosh_set_fn_port();
 516
 517         /* register the device file */
 518         retval = misc_register(&tosh_device);
 519         if (retval < 0)
 520                 return retval;
 521
 522 #ifdef CONFIG_PROC_FS
 523         {
 524                 struct proc_dir_entry *pde;
 525
 526                 pde = proc_create("toshiba", 0, NULL, &proc_toshiba_fops);
 527                 if (!pde) {
 528                         misc_deregister(&tosh_device);
 529                         return -ENOMEM;
 530                 }
 531         }
 532 #endif
 533
 534         return 0;
 535 }
 536
 537 static void __exit toshiba_exit(void)
 538 {
 539         remove_proc_entry("toshiba", NULL);
 540         misc_deregister(&tosh_device);
 541 }
 542
 543 module_init(toshiba_init);
 544 module_exit(toshiba_exit);
 545