xref: /openbmc/linux/drivers/char/toshiba.c (revision e3d786a3)
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 <linux/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 #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 Management 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 	{
512 		struct proc_dir_entry *pde;
513 
514 		pde = proc_create_single("toshiba", 0, NULL, proc_toshiba_show);
515 		if (!pde) {
516 			misc_deregister(&tosh_device);
517 			return -ENOMEM;
518 		}
519 	}
520 #endif
521 
522 	return 0;
523 }
524 
525 static void __exit toshiba_exit(void)
526 {
527 	remove_proc_entry("toshiba", NULL);
528 	misc_deregister(&tosh_device);
529 }
530 
531 module_init(toshiba_init);
532 module_exit(toshiba_exit);
533 
534