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 const 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 EXPORT_SYMBOL(tosh_smm);
 253
 254
 255 static int tosh_ioctl(struct inode *ip, struct file *fp, unsigned int cmd,
 256         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                         if (tosh_fan==1) {
 279                                 if (((ax==0xf300) || (ax==0xf400)) && (bx==0x0004)) {
 280                                         err = tosh_emulate_fan(&regs);
 281                                         break;
 282                                 }
 283                         }
 284                         err = tosh_smm(&regs);
 285                         break;
 286                 default:
 287                         return -EINVAL;
 288         }
 289
 290         if (copy_to_user(argp, &regs, sizeof(SMMRegisters)))
 291                 return -EFAULT;
 292
 293         return (err==0) ? 0:-EINVAL;
 294 }
 295
 296
 297 /*
 298  * Print the information for /proc/toshiba
 299  */
 300 #ifdef CONFIG_PROC_FS
 301 static int tosh_get_info(char *buffer, char **start, off_t fpos, int length)
 302 {
 303         char *temp;
 304         int key;
 305
 306         temp = buffer;
 307         key = tosh_fn_status();
 308
 309         /* Arguments
 310              0) Linux driver version (this will change if format changes)
 311              1) Machine ID
 312              2) SCI version
 313              3) BIOS version (major, minor)
 314              4) BIOS date (in SCI date format)
 315              5) Fn Key status
 316         */
 317
 318         temp += sprintf(temp, "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
 327         return temp-buffer;
 328 }
 329 #endif
 330
 331
 332 /*
 333  * Determine which port to use for the Fn key status
 334  */
 335 static void tosh_set_fn_port(void)
 336 {
 337         switch (tosh_id) {
 338                 case 0xfc02: case 0xfc04: case 0xfc09: case 0xfc0a: case 0xfc10:
 339                 case 0xfc11: case 0xfc13: case 0xfc15: case 0xfc1a: case 0xfc1b:
 340                 case 0xfc5a:
 341                         tosh_fn = 0x62;
 342                         break;
 343                 case 0xfc08: case 0xfc17: case 0xfc1d: case 0xfcd1: case 0xfce0:
 344                 case 0xfce2:
 345                         tosh_fn = 0x68;
 346                         break;
 347                 default:
 348                         tosh_fn = 0x00;
 349                         break;
 350         }
 351
 352         return;
 353 }
 354
 355
 356 /*
 357  * Get the machine identification number of the current model
 358  */
 359 static int tosh_get_machine_id(void __iomem *bios)
 360 {
 361         int id;
 362         SMMRegisters regs;
 363         unsigned short bx,cx;
 364         unsigned long address;
 365
 366         id = (0x100*(int) readb(bios+0xfffe))+((int) readb(bios+0xfffa));
 367
 368         /* do we have a SCTTable machine identication number on our hands */
 369
 370         if (id==0xfc2f) {
 371
 372                 /* start by getting a pointer into the BIOS */
 373
 374                 regs.eax = 0xc000;
 375                 regs.ebx = 0x0000;
 376                 regs.ecx = 0x0000;
 377                 tosh_smm(&regs);
 378                 bx = (unsigned short) (regs.ebx & 0xffff);
 379
 380                 /* At this point in the Toshiba routines under MS Windows
 381                    the bx register holds 0xe6f5. However my code is producing
 382                    a different value! For the time being I will just fudge the
 383                    value. This has been verified on a Satellite Pro 430CDT,
 384                    Tecra 750CDT, Tecra 780DVD and Satellite 310CDT. */
 385 #if TOSH_DEBUG
 386                 printk("toshiba: debugging ID ebx=0x%04x\n", regs.ebx);
 387 #endif
 388                 bx = 0xe6f5;
 389
 390                 /* now twiddle with our pointer a bit */
 391
 392                 address = bx;
 393                 cx = readw(bios + address);
 394                 address = 9+bx+cx;
 395                 cx = readw(bios + address);
 396                 address = 0xa+cx;
 397                 cx = readw(bios + address);
 398
 399                 /* now construct our machine identification number */
 400
 401                 id = ((cx & 0xff)<<8)+((cx & 0xff00)>>8);
 402         }
 403
 404         return id;
 405 }
 406
 407
 408 /*
 409  * Probe for the presence of a Toshiba laptop
 410  *
 411  *   returns and non-zero if unable to detect the presence of a Toshiba
 412  *   laptop, otherwise zero and determines the Machine ID, BIOS version and
 413  *   date, and SCI version.
 414  */
 415 static int tosh_probe(void)
 416 {
 417         int i,major,minor,day,year,month,flag;
 418         unsigned char signature[7] = { 0x54,0x4f,0x53,0x48,0x49,0x42,0x41 };
 419         SMMRegisters regs;
 420         void __iomem *bios = ioremap(0xf0000, 0x10000);
 421
 422         if (!bios)
 423                 return -ENOMEM;
 424
 425         /* extra sanity check for the string "TOSHIBA" in the BIOS because
 426            some machines that are not Toshiba's pass the next test */
 427
 428         for (i=0;i<7;i++) {
 429                 if (readb(bios+0xe010+i)!=signature[i]) {
 430                         printk("toshiba: not a supported Toshiba laptop\n");
 431                         iounmap(bios);
 432                         return -ENODEV;
 433                 }
 434         }
 435
 436         /* call the Toshiba SCI support check routine */
 437
 438         regs.eax = 0xf0f0;
 439         regs.ebx = 0x0000;
 440         regs.ecx = 0x0000;
 441         flag = tosh_smm(&regs);
 442
 443         /* if this is not a Toshiba laptop carry flag is set and ah=0x86 */
 444
 445         if ((flag==1) || ((regs.eax & 0xff00)==0x8600)) {
 446                 printk("toshiba: not a supported Toshiba laptop\n");
 447                 iounmap(bios);
 448                 return -ENODEV;
 449         }
 450
 451         /* if we get this far then we are running on a Toshiba (probably)! */
 452
 453         tosh_sci = regs.edx & 0xffff;
 454
 455         /* next get the machine ID of the current laptop */
 456
 457         tosh_id = tosh_get_machine_id(bios);
 458
 459         /* get the BIOS version */
 460
 461         major = readb(bios+0xe009)-'0';
 462         minor = ((readb(bios+0xe00b)-'0')*10)+(readb(bios+0xe00c)-'0');
 463         tosh_bios = (major*0x100)+minor;
 464
 465         /* get the BIOS date */
 466
 467         day = ((readb(bios+0xfff5)-'0')*10)+(readb(bios+0xfff6)-'0');
 468         month = ((readb(bios+0xfff8)-'0')*10)+(readb(bios+0xfff9)-'0');
 469         year = ((readb(bios+0xfffb)-'0')*10)+(readb(bios+0xfffc)-'0');
 470         tosh_date = (((year-90) & 0x1f)<<10) | ((month & 0xf)<<6)
 471                 | ((day & 0x1f)<<1);
 472
 473
 474         /* in theory we should check the ports we are going to use for the
 475            fn key detection (and the fan on the Portage 610/Tecra700), and
 476            then request them to stop other drivers using them. However as
 477            the keyboard driver grabs 0x60-0x6f and the pic driver grabs
 478            0xa0-0xbf we can't. We just have to live dangerously and use the
 479            ports anyway, oh boy! */
 480
 481         /* do we need to emulate the fan? */
 482
 483         if ((tosh_id==0xfccb) || (tosh_id==0xfccc))
 484                 tosh_fan = 1;
 485
 486         iounmap(bios);
 487
 488         return 0;
 489 }
 490
 491 static int __init toshiba_init(void)
 492 {
 493         int retval;
 494         /* are we running on a Toshiba laptop */
 495
 496         if (tosh_probe())
 497                 return -ENODEV;
 498
 499         printk(KERN_INFO "Toshiba System Managment Mode driver v" TOSH_VERSION "\n");
 500
 501         /* set the port to use for Fn status if not specified as a parameter */
 502         if (tosh_fn==0x00)
 503                 tosh_set_fn_port();
 504
 505         /* register the device file */
 506         retval = misc_register(&tosh_device);
 507         if (retval < 0)
 508                 return retval;
 509
 510 #ifdef CONFIG_PROC_FS
 511         /* register the proc entry */
 512         if (create_proc_info_entry("toshiba", 0, NULL, tosh_get_info) == NULL) {
 513                 misc_deregister(&tosh_device);
 514                 return -ENOMEM;
 515         }
 516 #endif
 517
 518         return 0;
 519 }
 520
 521 static void __exit toshiba_exit(void)
 522 {
 523         remove_proc_entry("toshiba", NULL);
 524         misc_deregister(&tosh_device);
 525 }
 526
 527 module_init(toshiba_init);
 528 module_exit(toshiba_exit);
 529