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 MODULE_LICENSE("GPL");
65 MODULE_AUTHOR("Jonathan Buzzard <jonathan@buzzard.org.uk>");
66 MODULE_DESCRIPTION("Toshiba laptop SMM driver");
67
68 static DEFINE_MUTEX(tosh_mutex);
69 static int tosh_fn;
70 module_param_named(fn, tosh_fn, int, 0);
71 MODULE_PARM_DESC(fn, "User specified Fn key detection port");
72
73 static int tosh_id;
74 static int tosh_bios;
75 static int tosh_date;
76 static int tosh_sci;
77 static int tosh_fan;
78
79 static long tosh_ioctl(struct file *, unsigned int,
80 unsigned long);
81
82
83 static const struct file_operations tosh_fops = {
84 .owner = THIS_MODULE,
85 .unlocked_ioctl = tosh_ioctl,
86 .llseek = noop_llseek,
87 };
88
89 static struct miscdevice tosh_device = {
90 TOSH_MINOR_DEV,
91 "toshiba",
92 &tosh_fops
93 };
94
95 /*
96 * Read the Fn key status
97 */
98 #ifdef CONFIG_PROC_FS
tosh_fn_status(void)99 static int tosh_fn_status(void)
100 {
101 unsigned char scan;
102 unsigned long flags;
103
104 if (tosh_fn!=0) {
105 scan = inb(tosh_fn);
106 } else {
107 local_irq_save(flags);
108 outb(0x8e, 0xe4);
109 scan = inb(0xe5);
110 local_irq_restore(flags);
111 }
112
113 return (int) scan;
114 }
115 #endif
116
117
118 /*
119 * For the Portage 610CT and the Tecra 700CS/700CDT emulate the HCI fan function
120 */
tosh_emulate_fan(SMMRegisters * regs)121 static int tosh_emulate_fan(SMMRegisters *regs)
122 {
123 unsigned long eax,ecx,flags;
124 unsigned char al;
125
126 eax = regs->eax & 0xff00;
127 ecx = regs->ecx & 0xffff;
128
129 /* Portage 610CT */
130
131 if (tosh_id==0xfccb) {
132 if (eax==0xfe00) {
133 /* fan status */
134 local_irq_save(flags);
135 outb(0xbe, 0xe4);
136 al = inb(0xe5);
137 local_irq_restore(flags);
138 regs->eax = 0x00;
139 regs->ecx = (unsigned int) (al & 0x01);
140 }
141 if ((eax==0xff00) && (ecx==0x0000)) {
142 /* fan off */
143 local_irq_save(flags);
144 outb(0xbe, 0xe4);
145 al = inb(0xe5);
146 outb(0xbe, 0xe4);
147 outb (al | 0x01, 0xe5);
148 local_irq_restore(flags);
149 regs->eax = 0x00;
150 regs->ecx = 0x00;
151 }
152 if ((eax==0xff00) && (ecx==0x0001)) {
153 /* fan on */
154 local_irq_save(flags);
155 outb(0xbe, 0xe4);
156 al = inb(0xe5);
157 outb(0xbe, 0xe4);
158 outb(al & 0xfe, 0xe5);
159 local_irq_restore(flags);
160 regs->eax = 0x00;
161 regs->ecx = 0x01;
162 }
163 }
164
165 /* Tecra 700CS/CDT */
166
167 if (tosh_id==0xfccc) {
168 if (eax==0xfe00) {
169 /* fan status */
170 local_irq_save(flags);
171 outb(0xe0, 0xe4);
172 al = inb(0xe5);
173 local_irq_restore(flags);
174 regs->eax = 0x00;
175 regs->ecx = al & 0x01;
176 }
177 if ((eax==0xff00) && (ecx==0x0000)) {
178 /* fan off */
179 local_irq_save(flags);
180 outb(0xe0, 0xe4);
181 al = inb(0xe5);
182 outw(0xe0 | ((al & 0xfe) << 8), 0xe4);
183 local_irq_restore(flags);
184 regs->eax = 0x00;
185 regs->ecx = 0x00;
186 }
187 if ((eax==0xff00) && (ecx==0x0001)) {
188 /* fan on */
189 local_irq_save(flags);
190 outb(0xe0, 0xe4);
191 al = inb(0xe5);
192 outw(0xe0 | ((al | 0x01) << 8), 0xe4);
193 local_irq_restore(flags);
194 regs->eax = 0x00;
195 regs->ecx = 0x01;
196 }
197 }
198
199 return 0;
200 }
201
202
203 /*
204 * Put the laptop into System Management Mode
205 */
tosh_smm(SMMRegisters * regs)206 int tosh_smm(SMMRegisters *regs)
207 {
208 int eax;
209
210 asm ("# load the values into the registers\n\t" \
211 "pushl %%eax\n\t" \
212 "movl 0(%%eax),%%edx\n\t" \
213 "push %%edx\n\t" \
214 "movl 4(%%eax),%%ebx\n\t" \
215 "movl 8(%%eax),%%ecx\n\t" \
216 "movl 12(%%eax),%%edx\n\t" \
217 "movl 16(%%eax),%%esi\n\t" \
218 "movl 20(%%eax),%%edi\n\t" \
219 "popl %%eax\n\t" \
220 "# call the System Management mode\n\t" \
221 "inb $0xb2,%%al\n\t"
222 "# fill out the memory with the values in the registers\n\t" \
223 "xchgl %%eax,(%%esp)\n\t"
224 "movl %%ebx,4(%%eax)\n\t" \
225 "movl %%ecx,8(%%eax)\n\t" \
226 "movl %%edx,12(%%eax)\n\t" \
227 "movl %%esi,16(%%eax)\n\t" \
228 "movl %%edi,20(%%eax)\n\t" \
229 "popl %%edx\n\t" \
230 "movl %%edx,0(%%eax)\n\t" \
231 "# setup the return value to the carry flag\n\t" \
232 "lahf\n\t" \
233 "shrl $8,%%eax\n\t" \
234 "andl $1,%%eax\n" \
235 : "=a" (eax)
236 : "a" (regs)
237 : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
238
239 return eax;
240 }
241 EXPORT_SYMBOL(tosh_smm);
242
243
tosh_ioctl(struct file * fp,unsigned int cmd,unsigned long arg)244 static long tosh_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
245 {
246 SMMRegisters regs;
247 SMMRegisters __user *argp = (SMMRegisters __user *)arg;
248 unsigned short ax,bx;
249 int err;
250
251 if (!argp)
252 return -EINVAL;
253
254 if (copy_from_user(®s, argp, sizeof(SMMRegisters)))
255 return -EFAULT;
256
257 switch (cmd) {
258 case TOSH_SMM:
259 ax = regs.eax & 0xff00;
260 bx = regs.ebx & 0xffff;
261 /* block HCI calls to read/write memory & PCI devices */
262 if (((ax==0xff00) || (ax==0xfe00)) && (bx>0x0069))
263 return -EINVAL;
264
265 /* do we need to emulate the fan ? */
266 mutex_lock(&tosh_mutex);
267 if (tosh_fan==1) {
268 if (((ax==0xf300) || (ax==0xf400)) && (bx==0x0004)) {
269 err = tosh_emulate_fan(®s);
270 mutex_unlock(&tosh_mutex);
271 break;
272 }
273 }
274 err = tosh_smm(®s);
275 mutex_unlock(&tosh_mutex);
276 break;
277 default:
278 return -EINVAL;
279 }
280
281 if (copy_to_user(argp, ®s, sizeof(SMMRegisters)))
282 return -EFAULT;
283
284 return (err==0) ? 0:-EINVAL;
285 }
286
287
288 /*
289 * Print the information for /proc/toshiba
290 */
291 #ifdef CONFIG_PROC_FS
proc_toshiba_show(struct seq_file * m,void * v)292 static int proc_toshiba_show(struct seq_file *m, void *v)
293 {
294 int key;
295
296 key = tosh_fn_status();
297
298 /* Arguments
299 0) Linux driver version (this will change if format changes)
300 1) Machine ID
301 2) SCI version
302 3) BIOS version (major, minor)
303 4) BIOS date (in SCI date format)
304 5) Fn Key status
305 */
306 seq_printf(m, "1.1 0x%04x %d.%d %d.%d 0x%04x 0x%02x\n",
307 tosh_id,
308 (tosh_sci & 0xff00)>>8,
309 tosh_sci & 0xff,
310 (tosh_bios & 0xff00)>>8,
311 tosh_bios & 0xff,
312 tosh_date,
313 key);
314 return 0;
315 }
316 #endif
317
318
319 /*
320 * Determine which port to use for the Fn key status
321 */
tosh_set_fn_port(void)322 static void tosh_set_fn_port(void)
323 {
324 switch (tosh_id) {
325 case 0xfc02: case 0xfc04: case 0xfc09: case 0xfc0a: case 0xfc10:
326 case 0xfc11: case 0xfc13: case 0xfc15: case 0xfc1a: case 0xfc1b:
327 case 0xfc5a:
328 tosh_fn = 0x62;
329 break;
330 case 0xfc08: case 0xfc17: case 0xfc1d: case 0xfcd1: case 0xfce0:
331 case 0xfce2:
332 tosh_fn = 0x68;
333 break;
334 default:
335 tosh_fn = 0x00;
336 break;
337 }
338
339 return;
340 }
341
342
343 /*
344 * Get the machine identification number of the current model
345 */
tosh_get_machine_id(void __iomem * bios)346 static int tosh_get_machine_id(void __iomem *bios)
347 {
348 int id;
349 SMMRegisters regs;
350 unsigned short bx,cx;
351 unsigned long address;
352
353 id = (0x100*(int) readb(bios+0xfffe))+((int) readb(bios+0xfffa));
354
355 /* do we have a SCTTable machine identication number on our hands */
356
357 if (id==0xfc2f) {
358
359 /* start by getting a pointer into the BIOS */
360
361 regs.eax = 0xc000;
362 regs.ebx = 0x0000;
363 regs.ecx = 0x0000;
364 tosh_smm(®s);
365 bx = (unsigned short) (regs.ebx & 0xffff);
366
367 /* At this point in the Toshiba routines under MS Windows
368 the bx register holds 0xe6f5. However my code is producing
369 a different value! For the time being I will just fudge the
370 value. This has been verified on a Satellite Pro 430CDT,
371 Tecra 750CDT, Tecra 780DVD and Satellite 310CDT. */
372 #if TOSH_DEBUG
373 pr_debug("toshiba: debugging ID ebx=0x%04x\n", regs.ebx);
374 #endif
375 bx = 0xe6f5;
376
377 /* now twiddle with our pointer a bit */
378
379 address = bx;
380 cx = readw(bios + address);
381 address = 9+bx+cx;
382 cx = readw(bios + address);
383 address = 0xa+cx;
384 cx = readw(bios + address);
385
386 /* now construct our machine identification number */
387
388 id = ((cx & 0xff)<<8)+((cx & 0xff00)>>8);
389 }
390
391 return id;
392 }
393
394
395 /*
396 * Probe for the presence of a Toshiba laptop
397 *
398 * returns and non-zero if unable to detect the presence of a Toshiba
399 * laptop, otherwise zero and determines the Machine ID, BIOS version and
400 * date, and SCI version.
401 */
tosh_probe(void)402 static int tosh_probe(void)
403 {
404 int i,major,minor,day,year,month,flag;
405 unsigned char signature[7] = { 0x54,0x4f,0x53,0x48,0x49,0x42,0x41 };
406 SMMRegisters regs;
407 void __iomem *bios = ioremap(0xf0000, 0x10000);
408
409 if (!bios)
410 return -ENOMEM;
411
412 /* extra sanity check for the string "TOSHIBA" in the BIOS because
413 some machines that are not Toshiba's pass the next test */
414
415 for (i=0;i<7;i++) {
416 if (readb(bios+0xe010+i)!=signature[i]) {
417 pr_err("toshiba: not a supported Toshiba laptop\n");
418 iounmap(bios);
419 return -ENODEV;
420 }
421 }
422
423 /* call the Toshiba SCI support check routine */
424
425 regs.eax = 0xf0f0;
426 regs.ebx = 0x0000;
427 regs.ecx = 0x0000;
428 flag = tosh_smm(®s);
429
430 /* if this is not a Toshiba laptop carry flag is set and ah=0x86 */
431
432 if ((flag==1) || ((regs.eax & 0xff00)==0x8600)) {
433 pr_err("toshiba: not a supported Toshiba laptop\n");
434 iounmap(bios);
435 return -ENODEV;
436 }
437
438 /* if we get this far then we are running on a Toshiba (probably)! */
439
440 tosh_sci = regs.edx & 0xffff;
441
442 /* next get the machine ID of the current laptop */
443
444 tosh_id = tosh_get_machine_id(bios);
445
446 /* get the BIOS version */
447
448 major = readb(bios+0xe009)-'0';
449 minor = ((readb(bios+0xe00b)-'0')*10)+(readb(bios+0xe00c)-'0');
450 tosh_bios = (major*0x100)+minor;
451
452 /* get the BIOS date */
453
454 day = ((readb(bios+0xfff5)-'0')*10)+(readb(bios+0xfff6)-'0');
455 month = ((readb(bios+0xfff8)-'0')*10)+(readb(bios+0xfff9)-'0');
456 year = ((readb(bios+0xfffb)-'0')*10)+(readb(bios+0xfffc)-'0');
457 tosh_date = (((year-90) & 0x1f)<<10) | ((month & 0xf)<<6)
458 | ((day & 0x1f)<<1);
459
460
461 /* in theory we should check the ports we are going to use for the
462 fn key detection (and the fan on the Portage 610/Tecra700), and
463 then request them to stop other drivers using them. However as
464 the keyboard driver grabs 0x60-0x6f and the pic driver grabs
465 0xa0-0xbf we can't. We just have to live dangerously and use the
466 ports anyway, oh boy! */
467
468 /* do we need to emulate the fan? */
469
470 if ((tosh_id==0xfccb) || (tosh_id==0xfccc))
471 tosh_fan = 1;
472
473 iounmap(bios);
474
475 return 0;
476 }
477
toshiba_init(void)478 static int __init toshiba_init(void)
479 {
480 int retval;
481 /* are we running on a Toshiba laptop */
482
483 if (tosh_probe())
484 return -ENODEV;
485
486 pr_info("Toshiba System Management Mode driver v" TOSH_VERSION "\n");
487
488 /* set the port to use for Fn status if not specified as a parameter */
489 if (tosh_fn==0x00)
490 tosh_set_fn_port();
491
492 /* register the device file */
493 retval = misc_register(&tosh_device);
494 if (retval < 0)
495 return retval;
496
497 #ifdef CONFIG_PROC_FS
498 {
499 struct proc_dir_entry *pde;
500
501 pde = proc_create_single("toshiba", 0, NULL, proc_toshiba_show);
502 if (!pde) {
503 misc_deregister(&tosh_device);
504 return -ENOMEM;
505 }
506 }
507 #endif
508
509 return 0;
510 }
511
toshiba_exit(void)512 static void __exit toshiba_exit(void)
513 {
514 remove_proc_entry("toshiba", NULL);
515 misc_deregister(&tosh_device);
516 }
517
518 module_init(toshiba_init);
519 module_exit(toshiba_exit);
520
521