1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* toshiba.c -- Linux driver for accessing the SMM on Toshiba laptops
3 *
4 * Copyright (c) 1996-2001 Jonathan A. Buzzard (jonathan@buzzard.org.uk)
5 *
6 * Valuable assistance and patches from:
7 * Tom May <tom@you-bastards.com>
8 * Rob Napier <rnapier@employees.org>
9 *
10 * Fn status port numbers for machine ID's courtesy of
11 * 0xfc02: Scott Eisert <scott.e@sky-eye.com>
12 * 0xfc04: Steve VanDevender <stevev@efn.org>
13 * 0xfc08: Garth Berry <garth@itsbruce.net>
14 * 0xfc0a: Egbert Eich <eich@xfree86.org>
15 * 0xfc10: Andrew Lofthouse <Andrew.Lofthouse@robins.af.mil>
16 * 0xfc11: Spencer Olson <solson@novell.com>
17 * 0xfc13: Claudius Frankewitz <kryp@gmx.de>
18 * 0xfc15: Tom May <tom@you-bastards.com>
19 * 0xfc17: Dave Konrad <konrad@xenia.it>
20 * 0xfc1a: George Betzos <betzos@engr.colostate.edu>
21 * 0xfc1b: Munemasa Wada <munemasa@jnovel.co.jp>
22 * 0xfc1d: Arthur Liu <armie@slap.mine.nu>
23 * 0xfc5a: Jacques L'helgoualc'h <lhh@free.fr>
24 * 0xfcd1: Mr. Dave Konrad <konrad@xenia.it>
25 *
26 * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
27 *
28 * This code is covered by the GNU GPL and you are free to make any
29 * changes you wish to it under the terms of the license. However the
30 * code has the potential to render your computer and/or someone else's
31 * unusable. Please proceed with care when modifying the code.
32 *
33 * Note: Unfortunately the laptop hardware can close the System Configuration
34 * Interface on it's own accord. It is therefore necessary for *all*
35 * programs using this driver to be aware that *any* SCI call can fail at
36 * *any* time. It is up to any program to be aware of this eventuality
37 * and take appropriate steps.
38 *
39 * The information used to write this driver has been obtained by reverse
40 * engineering the software supplied by Toshiba for their portable computers in
41 * strict accordance with the European Council Directive 92/250/EEC on the legal
42 * protection of computer programs, and it's implementation into English Law by
43 * the Copyright (Computer Programs) Regulations 1992 (S.I. 1992 No.3233).
44 */
45
46 #define TOSH_VERSION "1.11 26/9/2001"
47 #define TOSH_DEBUG 0
48
49 #include <linux/module.h>
50 #include <linux/kernel.h>
51 #include <linux/types.h>
52 #include <linux/fcntl.h>
53 #include <linux/miscdevice.h>
54 #include <linux/ioport.h>
55 #include <asm/io.h>
56 #include <linux/uaccess.h>
57 #include <linux/init.h>
58 #include <linux/stat.h>
59 #include <linux/proc_fs.h>
60 #include <linux/seq_file.h>
61 #include <linux/mutex.h>
62 #include <linux/toshiba.h>
63
64 #define TOSH_MINOR_DEV 181
65
66 MODULE_LICENSE("GPL");
67 MODULE_AUTHOR("Jonathan Buzzard <jonathan@buzzard.org.uk>");
68 MODULE_DESCRIPTION("Toshiba laptop SMM driver");
69 MODULE_SUPPORTED_DEVICE("toshiba");
70
71 static DEFINE_MUTEX(tosh_mutex);
72 static int tosh_fn;
73 module_param_named(fn, tosh_fn, int, 0);
74 MODULE_PARM_DESC(fn, "User specified Fn key detection port");
75
76 static int tosh_id;
77 static int tosh_bios;
78 static int tosh_date;
79 static int tosh_sci;
80 static int tosh_fan;
81
82 static long tosh_ioctl(struct file *, unsigned int,
83 unsigned long);
84
85
86 static const struct file_operations tosh_fops = {
87 .owner = THIS_MODULE,
88 .unlocked_ioctl = tosh_ioctl,
89 .llseek = noop_llseek,
90 };
91
92 static struct miscdevice tosh_device = {
93 TOSH_MINOR_DEV,
94 "toshiba",
95 &tosh_fops
96 };
97
98 /*
99 * Read the Fn key status
100 */
101 #ifdef CONFIG_PROC_FS
102 static int tosh_fn_status(void)
103 {
104 unsigned char scan;
105 unsigned long flags;
106
107 if (tosh_fn!=0) {
108 scan = inb(tosh_fn);
109 } else {
110 local_irq_save(flags);
111 outb(0x8e, 0xe4);
112 scan = inb(0xe5);
113 local_irq_restore(flags);
114 }
115
116 return (int) scan;
117 }
118 #endif
119
120
121 /*
122 * For the Portage 610CT and the Tecra 700CS/700CDT emulate the HCI fan function
123 */
124 static int tosh_emulate_fan(SMMRegisters *regs)
125 {
126 unsigned long eax,ecx,flags;
127 unsigned char al;
128
129 eax = regs->eax & 0xff00;
130 ecx = regs->ecx & 0xffff;
131
132 /* Portage 610CT */
133
134 if (tosh_id==0xfccb) {
135 if (eax==0xfe00) {
136 /* fan status */
137 local_irq_save(flags);
138 outb(0xbe, 0xe4);
139 al = inb(0xe5);
140 local_irq_restore(flags);
141 regs->eax = 0x00;
142 regs->ecx = (unsigned int) (al & 0x01);
143 }
144 if ((eax==0xff00) && (ecx==0x0000)) {
145 /* fan off */
146 local_irq_save(flags);
147 outb(0xbe, 0xe4);
148 al = inb(0xe5);
149 outb(0xbe, 0xe4);
150 outb (al | 0x01, 0xe5);
151 local_irq_restore(flags);
152 regs->eax = 0x00;
153 regs->ecx = 0x00;
154 }
155 if ((eax==0xff00) && (ecx==0x0001)) {
156 /* fan on */
157 local_irq_save(flags);
158 outb(0xbe, 0xe4);
159 al = inb(0xe5);
160 outb(0xbe, 0xe4);
161 outb(al & 0xfe, 0xe5);
162 local_irq_restore(flags);
163 regs->eax = 0x00;
164 regs->ecx = 0x01;
165 }
166 }
167
168 /* Tecra 700CS/CDT */
169
170 if (tosh_id==0xfccc) {
171 if (eax==0xfe00) {
172 /* fan status */
173 local_irq_save(flags);
174 outb(0xe0, 0xe4);
175 al = inb(0xe5);
176 local_irq_restore(flags);
177 regs->eax = 0x00;
178 regs->ecx = al & 0x01;
179 }
180 if ((eax==0xff00) && (ecx==0x0000)) {
181 /* fan off */
182 local_irq_save(flags);
183 outb(0xe0, 0xe4);
184 al = inb(0xe5);
185 outw(0xe0 | ((al & 0xfe) << 8), 0xe4);
186 local_irq_restore(flags);
187 regs->eax = 0x00;
188 regs->ecx = 0x00;
189 }
190 if ((eax==0xff00) && (ecx==0x0001)) {
191 /* fan on */
192 local_irq_save(flags);
193 outb(0xe0, 0xe4);
194 al = inb(0xe5);
195 outw(0xe0 | ((al | 0x01) << 8), 0xe4);
196 local_irq_restore(flags);
197 regs->eax = 0x00;
198 regs->ecx = 0x01;
199 }
200 }
201
202 return 0;
203 }
204
205
206 /*
207 * Put the laptop into System Management Mode
208 */
209 int tosh_smm(SMMRegisters *regs)
210 {
211 int eax;
212
213 asm ("# load the values into the registers\n\t" \
214 "pushl %%eax\n\t" \
215 "movl 0(%%eax),%%edx\n\t" \
216 "push %%edx\n\t" \
217 "movl 4(%%eax),%%ebx\n\t" \
218 "movl 8(%%eax),%%ecx\n\t" \
219 "movl 12(%%eax),%%edx\n\t" \
220 "movl 16(%%eax),%%esi\n\t" \
221 "movl 20(%%eax),%%edi\n\t" \
222 "popl %%eax\n\t" \
223 "# call the System Management mode\n\t" \
224 "inb $0xb2,%%al\n\t"
225 "# fill out the memory with the values in the registers\n\t" \
226 "xchgl %%eax,(%%esp)\n\t"
227 "movl %%ebx,4(%%eax)\n\t" \
228 "movl %%ecx,8(%%eax)\n\t" \
229 "movl %%edx,12(%%eax)\n\t" \
230 "movl %%esi,16(%%eax)\n\t" \
231 "movl %%edi,20(%%eax)\n\t" \
232 "popl %%edx\n\t" \
233 "movl %%edx,0(%%eax)\n\t" \
234 "# setup the return value to the carry flag\n\t" \
235 "lahf\n\t" \
236 "shrl $8,%%eax\n\t" \
237 "andl $1,%%eax\n" \
238 : "=a" (eax)
239 : "a" (regs)
240 : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
241
242 return eax;
243 }
244 EXPORT_SYMBOL(tosh_smm);
245
246
247 static long tosh_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
248 {
249 SMMRegisters regs;
250 SMMRegisters __user *argp = (SMMRegisters __user *)arg;
251 unsigned short ax,bx;
252 int err;
253
254 if (!argp)
255 return -EINVAL;
256
257 if (copy_from_user(®s, argp, sizeof(SMMRegisters)))
258 return -EFAULT;
259
260 switch (cmd) {
261 case TOSH_SMM:
262 ax = regs.eax & 0xff00;
263 bx = regs.ebx & 0xffff;
264 /* block HCI calls to read/write memory & PCI devices */
265 if (((ax==0xff00) || (ax==0xfe00)) && (bx>0x0069))
266 return -EINVAL;
267
268 /* do we need to emulate the fan ? */
269 mutex_lock(&tosh_mutex);
270 if (tosh_fan==1) {
271 if (((ax==0xf300) || (ax==0xf400)) && (bx==0x0004)) {
272 err = tosh_emulate_fan(®s);
273 mutex_unlock(&tosh_mutex);
274 break;
275 }
276 }
277 err = tosh_smm(®s);
278 mutex_unlock(&tosh_mutex);
279 break;
280 default:
281 return -EINVAL;
282 }
283
284 if (copy_to_user(argp, ®s, sizeof(SMMRegisters)))
285 return -EFAULT;
286
287 return (err==0) ? 0:-EINVAL;
288 }
289
290
291 /*
292 * Print the information for /proc/toshiba
293 */
294 #ifdef CONFIG_PROC_FS
295 static int proc_toshiba_show(struct seq_file *m, void *v)
296 {
297 int key;
298
299 key = tosh_fn_status();
300
301 /* Arguments
302 0) Linux driver version (this will change if format changes)
303 1) Machine ID
304 2) SCI version
305 3) BIOS version (major, minor)
306 4) BIOS date (in SCI date format)
307 5) Fn Key status
308 */
309 seq_printf(m, "1.1 0x%04x %d.%d %d.%d 0x%04x 0x%02x\n",
310 tosh_id,
311 (tosh_sci & 0xff00)>>8,
312 tosh_sci & 0xff,
313 (tosh_bios & 0xff00)>>8,
314 tosh_bios & 0xff,
315 tosh_date,
316 key);
317 return 0;
318 }
319 #endif
320
321
322 /*
323 * Determine which port to use for the Fn key status
324 */
325 static void tosh_set_fn_port(void)
326 {
327 switch (tosh_id) {
328 case 0xfc02: case 0xfc04: case 0xfc09: case 0xfc0a: case 0xfc10:
329 case 0xfc11: case 0xfc13: case 0xfc15: case 0xfc1a: case 0xfc1b:
330 case 0xfc5a:
331 tosh_fn = 0x62;
332 break;
333 case 0xfc08: case 0xfc17: case 0xfc1d: case 0xfcd1: case 0xfce0:
334 case 0xfce2:
335 tosh_fn = 0x68;
336 break;
337 default:
338 tosh_fn = 0x00;
339 break;
340 }
341
342 return;
343 }
344
345
346 /*
347 * Get the machine identification number of the current model
348 */
349 static int tosh_get_machine_id(void __iomem *bios)
350 {
351 int id;
352 SMMRegisters regs;
353 unsigned short bx,cx;
354 unsigned long address;
355
356 id = (0x100*(int) readb(bios+0xfffe))+((int) readb(bios+0xfffa));
357
358 /* do we have a SCTTable machine identication number on our hands */
359
360 if (id==0xfc2f) {
361
362 /* start by getting a pointer into the BIOS */
363
364 regs.eax = 0xc000;
365 regs.ebx = 0x0000;
366 regs.ecx = 0x0000;
367 tosh_smm(®s);
368 bx = (unsigned short) (regs.ebx & 0xffff);
369
370 /* At this point in the Toshiba routines under MS Windows
371 the bx register holds 0xe6f5. However my code is producing
372 a different value! For the time being I will just fudge the
373 value. This has been verified on a Satellite Pro 430CDT,
374 Tecra 750CDT, Tecra 780DVD and Satellite 310CDT. */
375 #if TOSH_DEBUG
376 pr_debug("toshiba: debugging ID ebx=0x%04x\n", regs.ebx);
377 #endif
378 bx = 0xe6f5;
379
380 /* now twiddle with our pointer a bit */
381
382 address = bx;
383 cx = readw(bios + address);
384 address = 9+bx+cx;
385 cx = readw(bios + address);
386 address = 0xa+cx;
387 cx = readw(bios + address);
388
389 /* now construct our machine identification number */
390
391 id = ((cx & 0xff)<<8)+((cx & 0xff00)>>8);
392 }
393
394 return id;
395 }
396
397
398 /*
399 * Probe for the presence of a Toshiba laptop
400 *
401 * returns and non-zero if unable to detect the presence of a Toshiba
402 * laptop, otherwise zero and determines the Machine ID, BIOS version and
403 * date, and SCI version.
404 */
405 static int tosh_probe(void)
406 {
407 int i,major,minor,day,year,month,flag;
408 unsigned char signature[7] = { 0x54,0x4f,0x53,0x48,0x49,0x42,0x41 };
409 SMMRegisters regs;
410 void __iomem *bios = ioremap(0xf0000, 0x10000);
411
412 if (!bios)
413 return -ENOMEM;
414
415 /* extra sanity check for the string "TOSHIBA" in the BIOS because
416 some machines that are not Toshiba's pass the next test */
417
418 for (i=0;i<7;i++) {
419 if (readb(bios+0xe010+i)!=signature[i]) {
420 pr_err("toshiba: not a supported Toshiba laptop\n");
421 iounmap(bios);
422 return -ENODEV;
423 }
424 }
425
426 /* call the Toshiba SCI support check routine */
427
428 regs.eax = 0xf0f0;
429 regs.ebx = 0x0000;
430 regs.ecx = 0x0000;
431 flag = tosh_smm(®s);
432
433 /* if this is not a Toshiba laptop carry flag is set and ah=0x86 */
434
435 if ((flag==1) || ((regs.eax & 0xff00)==0x8600)) {
436 pr_err("toshiba: not a supported Toshiba laptop\n");
437 iounmap(bios);
438 return -ENODEV;
439 }
440
441 /* if we get this far then we are running on a Toshiba (probably)! */
442
443 tosh_sci = regs.edx & 0xffff;
444
445 /* next get the machine ID of the current laptop */
446
447 tosh_id = tosh_get_machine_id(bios);
448
449 /* get the BIOS version */
450
451 major = readb(bios+0xe009)-'0';
452 minor = ((readb(bios+0xe00b)-'0')*10)+(readb(bios+0xe00c)-'0');
453 tosh_bios = (major*0x100)+minor;
454
455 /* get the BIOS date */
456
457 day = ((readb(bios+0xfff5)-'0')*10)+(readb(bios+0xfff6)-'0');
458 month = ((readb(bios+0xfff8)-'0')*10)+(readb(bios+0xfff9)-'0');
459 year = ((readb(bios+0xfffb)-'0')*10)+(readb(bios+0xfffc)-'0');
460 tosh_date = (((year-90) & 0x1f)<<10) | ((month & 0xf)<<6)
461 | ((day & 0x1f)<<1);
462
463
464 /* in theory we should check the ports we are going to use for the
465 fn key detection (and the fan on the Portage 610/Tecra700), and
466 then request them to stop other drivers using them. However as
467 the keyboard driver grabs 0x60-0x6f and the pic driver grabs
468 0xa0-0xbf we can't. We just have to live dangerously and use the
469 ports anyway, oh boy! */
470
471 /* do we need to emulate the fan? */
472
473 if ((tosh_id==0xfccb) || (tosh_id==0xfccc))
474 tosh_fan = 1;
475
476 iounmap(bios);
477
478 return 0;
479 }
480
481 static int __init toshiba_init(void)
482 {
483 int retval;
484 /* are we running on a Toshiba laptop */
485
486 if (tosh_probe())
487 return -ENODEV;
488
489 pr_info("Toshiba System Management Mode driver v" TOSH_VERSION "\n");
490
491 /* set the port to use for Fn status if not specified as a parameter */
492 if (tosh_fn==0x00)
493 tosh_set_fn_port();
494
495 /* register the device file */
496 retval = misc_register(&tosh_device);
497 if (retval < 0)
498 return retval;
499
500 #ifdef CONFIG_PROC_FS
501 {
502 struct proc_dir_entry *pde;
503
504 pde = proc_create_single("toshiba", 0, NULL, proc_toshiba_show);
505 if (!pde) {
506 misc_deregister(&tosh_device);
507 return -ENOMEM;
508 }
509 }
510 #endif
511
512 return 0;
513 }
514
515 static void __exit toshiba_exit(void)
516 {
517 remove_proc_entry("toshiba", NULL);
518 misc_deregister(&tosh_device);
519 }
520
521 module_init(toshiba_init);
522 module_exit(toshiba_exit);
523