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         .llseek         = noop_llseek,
 100 };
 101
 102 static struct miscdevice tosh_device = {
 103         TOSH_MINOR_DEV,
 104         "toshiba",
 105         &tosh_fops
 106 };
 107
 108 /*
 109  * Read the Fn key status
 110  */
 111 #ifdef CONFIG_PROC_FS
 112 static int tosh_fn_status(void)
 113 {
 114         unsigned char scan;
 115         unsigned long flags;
 116
 117         if (tosh_fn!=0) {
 118                 scan = inb(tosh_fn);
 119         } else {
 120                 local_irq_save(flags);
 121                 outb(0x8e, 0xe4);
 122                 scan = inb(0xe5);
 123                 local_irq_restore(flags);
 124         }
 125
 126         return (int) scan;
 127 }
 128 #endif
 129
 130
 131 /*
 132  * For the Portage 610CT and the Tecra 700CS/700CDT emulate the HCI fan function
 133  */
 134 static int tosh_emulate_fan(SMMRegisters *regs)
 135 {
 136         unsigned long eax,ecx,flags;
 137         unsigned char al;
 138
 139         eax = regs->eax & 0xff00;
 140         ecx = regs->ecx & 0xffff;
 141
 142         /* Portage 610CT */
 143
 144         if (tosh_id==0xfccb) {
 145                 if (eax==0xfe00) {
 146                         /* fan status */
 147                         local_irq_save(flags);
 148                         outb(0xbe, 0xe4);
 149                         al = inb(0xe5);
 150                         local_irq_restore(flags);
 151                         regs->eax = 0x00;
 152                         regs->ecx = (unsigned int) (al & 0x01);
 153                 }
 154                 if ((eax==0xff00) && (ecx==0x0000)) {
 155                         /* fan off */
 156                         local_irq_save(flags);
 157                         outb(0xbe, 0xe4);
 158                         al = inb(0xe5);
 159                         outb(0xbe, 0xe4);
 160                         outb (al | 0x01, 0xe5);
 161                         local_irq_restore(flags);
 162                         regs->eax = 0x00;
 163                         regs->ecx = 0x00;
 164                 }
 165                 if ((eax==0xff00) && (ecx==0x0001)) {
 166                         /* fan on */
 167                         local_irq_save(flags);
 168                         outb(0xbe, 0xe4);
 169                         al = inb(0xe5);
 170                         outb(0xbe, 0xe4);
 171                         outb(al & 0xfe, 0xe5);
 172                         local_irq_restore(flags);
 173                         regs->eax = 0x00;
 174                         regs->ecx = 0x01;
 175                 }
 176         }
 177
 178         /* Tecra 700CS/CDT */
 179
 180         if (tosh_id==0xfccc) {
 181                 if (eax==0xfe00) {
 182                         /* fan status */
 183                         local_irq_save(flags);
 184                         outb(0xe0, 0xe4);
 185                         al = inb(0xe5);
 186                         local_irq_restore(flags);
 187                         regs->eax = 0x00;
 188                         regs->ecx = al & 0x01;
 189                 }
 190                 if ((eax==0xff00) && (ecx==0x0000)) {
 191                         /* fan off */
 192                         local_irq_save(flags);
 193                         outb(0xe0, 0xe4);
 194                         al = inb(0xe5);
 195                         outw(0xe0 | ((al & 0xfe) << 8), 0xe4);
 196                         local_irq_restore(flags);
 197                         regs->eax = 0x00;
 198                         regs->ecx = 0x00;
 199                 }
 200                 if ((eax==0xff00) && (ecx==0x0001)) {
 201                         /* fan on */
 202                         local_irq_save(flags);
 203                         outb(0xe0, 0xe4);
 204                         al = inb(0xe5);
 205                         outw(0xe0 | ((al | 0x01) << 8), 0xe4);
 206                         local_irq_restore(flags);
 207                         regs->eax = 0x00;
 208                         regs->ecx = 0x01;
 209                 }
 210         }
 211
 212         return 0;
 213 }
 214
 215
 216 /*
 217  * Put the laptop into System Management Mode
 218  */
 219 int tosh_smm(SMMRegisters *regs)
 220 {
 221         int eax;
 222
 223         asm ("# load the values into the registers\n\t" \
 224                 "pushl %%eax\n\t" \
 225                 "movl 0(%%eax),%%edx\n\t" \
 226                 "push %%edx\n\t" \
 227                 "movl 4(%%eax),%%ebx\n\t" \
 228                 "movl 8(%%eax),%%ecx\n\t" \
 229                 "movl 12(%%eax),%%edx\n\t" \
 230                 "movl 16(%%eax),%%esi\n\t" \
 231                 "movl 20(%%eax),%%edi\n\t" \
 232                 "popl %%eax\n\t" \
 233                 "# call the System Management mode\n\t" \
 234                 "inb $0xb2,%%al\n\t"
 235                 "# fill out the memory with the values in the registers\n\t" \
 236                 "xchgl %%eax,(%%esp)\n\t"
 237                 "movl %%ebx,4(%%eax)\n\t" \
 238                 "movl %%ecx,8(%%eax)\n\t" \
 239                 "movl %%edx,12(%%eax)\n\t" \
 240                 "movl %%esi,16(%%eax)\n\t" \
 241                 "movl %%edi,20(%%eax)\n\t" \
 242                 "popl %%edx\n\t" \
 243                 "movl %%edx,0(%%eax)\n\t" \
 244                 "# setup the return value to the carry flag\n\t" \
 245                 "lahf\n\t" \
 246                 "shrl $8,%%eax\n\t" \
 247                 "andl $1,%%eax\n" \
 248                 : "=a" (eax)
 249                 : "a" (regs)
 250                 : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
 251
 252         return eax;
 253 }
 254 EXPORT_SYMBOL(tosh_smm);
 255
 256
 257 static long tosh_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
 258 {
 259         SMMRegisters regs;
 260         SMMRegisters __user *argp = (SMMRegisters __user *)arg;
 261         unsigned short ax,bx;
 262         int err;
 263
 264         if (!argp)
 265                 return -EINVAL;
 266
 267         if (copy_from_user(&regs, argp, sizeof(SMMRegisters)))
 268                 return -EFAULT;
 269
 270         switch (cmd) {
 271                 case TOSH_SMM:
 272                         ax = regs.eax & 0xff00;
 273                         bx = regs.ebx & 0xffff;
 274                         /* block HCI calls to read/write memory & PCI devices */
 275                         if (((ax==0xff00) || (ax==0xfe00)) && (bx>0x0069))
 276                                 return -EINVAL;
 277
 278                         /* do we need to emulate the fan ? */
 279                         mutex_lock(&tosh_mutex);
 280                         if (tosh_fan==1) {
 281                                 if (((ax==0xf300) || (ax==0xf400)) && (bx==0x0004)) {
 282                                         err = tosh_emulate_fan(&regs);
 283                                         mutex_unlock(&tosh_mutex);
 284                                         break;
 285                                 }
 286                         }
 287                         err = tosh_smm(&regs);
 288                         mutex_unlock(&tosh_mutex);
 289                         break;
 290                 default:
 291                         return -EINVAL;
 292         }
 293
 294         if (copy_to_user(argp, &regs, sizeof(SMMRegisters)))
 295                 return -EFAULT;
 296
 297         return (err==0) ? 0:-EINVAL;
 298 }
 299
 300
 301 /*
 302  * Print the information for /proc/toshiba
 303  */
 304 #ifdef CONFIG_PROC_FS
 305 static int proc_toshiba_show(struct seq_file *m, void *v)
 306 {
 307         int key;
 308
 309         key = tosh_fn_status();
 310
 311         /* Arguments
 312              0) Linux driver version (this will change if format changes)
 313              1) Machine ID
 314              2) SCI version
 315              3) BIOS version (major, minor)
 316              4) BIOS date (in SCI date format)
 317              5) Fn Key status
 318         */
 319         seq_printf(m, "1.1 0x%04x %d.%d %d.%d 0x%04x 0x%02x\n",
 320                 tosh_id,
 321                 (tosh_sci & 0xff00)>>8,
 322                 tosh_sci & 0xff,
 323                 (tosh_bios & 0xff00)>>8,
 324                 tosh_bios & 0xff,
 325                 tosh_date,
 326                 key);
 327         return 0;
 328 }
 329
 330 static int proc_toshiba_open(struct inode *inode, struct file *file)
 331 {
 332         return single_open(file, proc_toshiba_show, NULL);
 333 }
 334
 335 static const struct file_operations proc_toshiba_fops = {
 336         .owner          = THIS_MODULE,
 337         .open           = proc_toshiba_open,
 338         .read           = seq_read,
 339         .llseek         = seq_lseek,
 340         .release        = single_release,
 341 };
 342 #endif
 343
 344
 345 /*
 346  * Determine which port to use for the Fn key status
 347  */
 348 static void tosh_set_fn_port(void)
 349 {
 350         switch (tosh_id) {
 351                 case 0xfc02: case 0xfc04: case 0xfc09: case 0xfc0a: case 0xfc10:
 352                 case 0xfc11: case 0xfc13: case 0xfc15: case 0xfc1a: case 0xfc1b:
 353                 case 0xfc5a:
 354                         tosh_fn = 0x62;
 355                         break;
 356                 case 0xfc08: case 0xfc17: case 0xfc1d: case 0xfcd1: case 0xfce0:
 357                 case 0xfce2:
 358                         tosh_fn = 0x68;
 359                         break;
 360                 default:
 361                         tosh_fn = 0x00;
 362                         break;
 363         }
 364
 365         return;
 366 }
 367
 368
 369 /*
 370  * Get the machine identification number of the current model
 371  */
 372 static int tosh_get_machine_id(void __iomem *bios)
 373 {
 374         int id;
 375         SMMRegisters regs;
 376         unsigned short bx,cx;
 377         unsigned long address;
 378
 379         id = (0x100*(int) readb(bios+0xfffe))+((int) readb(bios+0xfffa));
 380
 381         /* do we have a SCTTable machine identication number on our hands */
 382
 383         if (id==0xfc2f) {
 384
 385                 /* start by getting a pointer into the BIOS */
 386
 387                 regs.eax = 0xc000;
 388                 regs.ebx = 0x0000;
 389                 regs.ecx = 0x0000;
 390                 tosh_smm(&regs);
 391                 bx = (unsigned short) (regs.ebx & 0xffff);
 392
 393                 /* At this point in the Toshiba routines under MS Windows
 394                    the bx register holds 0xe6f5. However my code is producing
 395                    a different value! For the time being I will just fudge the
 396                    value. This has been verified on a Satellite Pro 430CDT,
 397                    Tecra 750CDT, Tecra 780DVD and Satellite 310CDT. */
 398 #if TOSH_DEBUG
 399                 printk("toshiba: debugging ID ebx=0x%04x\n", regs.ebx);
 400 #endif
 401                 bx = 0xe6f5;
 402
 403                 /* now twiddle with our pointer a bit */
 404
 405                 address = bx;
 406                 cx = readw(bios + address);
 407                 address = 9+bx+cx;
 408                 cx = readw(bios + address);
 409                 address = 0xa+cx;
 410                 cx = readw(bios + address);
 411
 412                 /* now construct our machine identification number */
 413
 414                 id = ((cx & 0xff)<<8)+((cx & 0xff00)>>8);
 415         }
 416
 417         return id;
 418 }
 419
 420
 421 /*
 422  * Probe for the presence of a Toshiba laptop
 423  *
 424  *   returns and non-zero if unable to detect the presence of a Toshiba
 425  *   laptop, otherwise zero and determines the Machine ID, BIOS version and
 426  *   date, and SCI version.
 427  */
 428 static int tosh_probe(void)
 429 {
 430         int i,major,minor,day,year,month,flag;
 431         unsigned char signature[7] = { 0x54,0x4f,0x53,0x48,0x49,0x42,0x41 };
 432         SMMRegisters regs;
 433         void __iomem *bios = ioremap_cache(0xf0000, 0x10000);
 434
 435         if (!bios)
 436                 return -ENOMEM;
 437
 438         /* extra sanity check for the string "TOSHIBA" in the BIOS because
 439            some machines that are not Toshiba's pass the next test */
 440
 441         for (i=0;i<7;i++) {
 442                 if (readb(bios+0xe010+i)!=signature[i]) {
 443                         printk("toshiba: not a supported Toshiba laptop\n");
 444                         iounmap(bios);
 445                         return -ENODEV;
 446                 }
 447         }
 448
 449         /* call the Toshiba SCI support check routine */
 450
 451         regs.eax = 0xf0f0;
 452         regs.ebx = 0x0000;
 453         regs.ecx = 0x0000;
 454         flag = tosh_smm(&regs);
 455
 456         /* if this is not a Toshiba laptop carry flag is set and ah=0x86 */
 457
 458         if ((flag==1) || ((regs.eax & 0xff00)==0x8600)) {
 459                 printk("toshiba: not a supported Toshiba laptop\n");
 460                 iounmap(bios);
 461                 return -ENODEV;
 462         }
 463
 464         /* if we get this far then we are running on a Toshiba (probably)! */
 465
 466         tosh_sci = regs.edx & 0xffff;
 467
 468         /* next get the machine ID of the current laptop */
 469
 470         tosh_id = tosh_get_machine_id(bios);
 471
 472         /* get the BIOS version */
 473
 474         major = readb(bios+0xe009)-'0';
 475         minor = ((readb(bios+0xe00b)-'0')*10)+(readb(bios+0xe00c)-'0');
 476         tosh_bios = (major*0x100)+minor;
 477
 478         /* get the BIOS date */
 479
 480         day = ((readb(bios+0xfff5)-'0')*10)+(readb(bios+0xfff6)-'0');
 481         month = ((readb(bios+0xfff8)-'0')*10)+(readb(bios+0xfff9)-'0');
 482         year = ((readb(bios+0xfffb)-'0')*10)+(readb(bios+0xfffc)-'0');
 483         tosh_date = (((year-90) & 0x1f)<<10) | ((month & 0xf)<<6)
 484                 | ((day & 0x1f)<<1);
 485
 486
 487         /* in theory we should check the ports we are going to use for the
 488            fn key detection (and the fan on the Portage 610/Tecra700), and
 489            then request them to stop other drivers using them. However as
 490            the keyboard driver grabs 0x60-0x6f and the pic driver grabs
 491            0xa0-0xbf we can't. We just have to live dangerously and use the
 492            ports anyway, oh boy! */
 493
 494         /* do we need to emulate the fan? */
 495
 496         if ((tosh_id==0xfccb) || (tosh_id==0xfccc))
 497                 tosh_fan = 1;
 498
 499         iounmap(bios);
 500
 501         return 0;
 502 }
 503
 504 static int __init toshiba_init(void)
 505 {
 506         int retval;
 507         /* are we running on a Toshiba laptop */
 508
 509         if (tosh_probe())
 510                 return -ENODEV;
 511
 512         printk(KERN_INFO "Toshiba System Management Mode driver v" TOSH_VERSION "\n");
 513
 514         /* set the port to use for Fn status if not specified as a parameter */
 515         if (tosh_fn==0x00)
 516                 tosh_set_fn_port();
 517
 518         /* register the device file */
 519         retval = misc_register(&tosh_device);
 520         if (retval < 0)
 521                 return retval;
 522
 523 #ifdef CONFIG_PROC_FS
 524         {
 525                 struct proc_dir_entry *pde;
 526
 527                 pde = proc_create("toshiba", 0, NULL, &proc_toshiba_fops);
 528                 if (!pde) {
 529                         misc_deregister(&tosh_device);
 530                         return -ENOMEM;
 531                 }
 532         }
 533 #endif
 534
 535         return 0;
 536 }
 537
 538 static void __exit toshiba_exit(void)
 539 {
 540         remove_proc_entry("toshiba", NULL);
 541         misc_deregister(&tosh_device);
 542 }
 543
 544 module_init(toshiba_init);
 545 module_exit(toshiba_exit);
 546