xref: /openbmc/linux/drivers/char/toshiba.c (revision a09d2831)
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/smp_lock.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 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 long tosh_ioctl(struct file *, unsigned int,
92 	unsigned long);
93 
94 
95 static const struct file_operations tosh_fops = {
96 	.owner		= THIS_MODULE,
97 	.unlocked_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 long tosh_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
256 {
257 	SMMRegisters regs;
258 	SMMRegisters __user *argp = (SMMRegisters __user *)arg;
259 	unsigned short ax,bx;
260 	int err;
261 
262 	if (!argp)
263 		return -EINVAL;
264 
265 	if (copy_from_user(&regs, argp, sizeof(SMMRegisters)))
266 		return -EFAULT;
267 
268 	switch (cmd) {
269 		case TOSH_SMM:
270 			ax = regs.eax & 0xff00;
271 			bx = regs.ebx & 0xffff;
272 			/* block HCI calls to read/write memory & PCI devices */
273 			if (((ax==0xff00) || (ax==0xfe00)) && (bx>0x0069))
274 				return -EINVAL;
275 
276 			/* do we need to emulate the fan ? */
277 			lock_kernel();
278 			if (tosh_fan==1) {
279 				if (((ax==0xf300) || (ax==0xf400)) && (bx==0x0004)) {
280 					err = tosh_emulate_fan(&regs);
281 					unlock_kernel();
282 					break;
283 				}
284 			}
285 			err = tosh_smm(&regs);
286 			unlock_kernel();
287 			break;
288 		default:
289 			return -EINVAL;
290 	}
291 
292         if (copy_to_user(argp, &regs, sizeof(SMMRegisters)))
293         	return -EFAULT;
294 
295 	return (err==0) ? 0:-EINVAL;
296 }
297 
298 
299 /*
300  * Print the information for /proc/toshiba
301  */
302 #ifdef CONFIG_PROC_FS
303 static int proc_toshiba_show(struct seq_file *m, void *v)
304 {
305 	int key;
306 
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 	seq_printf(m, "1.1 0x%04x %d.%d %d.%d 0x%04x 0x%02x\n",
318 		tosh_id,
319 		(tosh_sci & 0xff00)>>8,
320 		tosh_sci & 0xff,
321 		(tosh_bios & 0xff00)>>8,
322 		tosh_bios & 0xff,
323 		tosh_date,
324 		key);
325 	return 0;
326 }
327 
328 static int proc_toshiba_open(struct inode *inode, struct file *file)
329 {
330 	return single_open(file, proc_toshiba_show, NULL);
331 }
332 
333 static const struct file_operations proc_toshiba_fops = {
334 	.owner		= THIS_MODULE,
335 	.open		= proc_toshiba_open,
336 	.read		= seq_read,
337 	.llseek		= seq_lseek,
338 	.release	= single_release,
339 };
340 #endif
341 
342 
343 /*
344  * Determine which port to use for the Fn key status
345  */
346 static void tosh_set_fn_port(void)
347 {
348 	switch (tosh_id) {
349 		case 0xfc02: case 0xfc04: case 0xfc09: case 0xfc0a: case 0xfc10:
350 		case 0xfc11: case 0xfc13: case 0xfc15: case 0xfc1a: case 0xfc1b:
351 		case 0xfc5a:
352 			tosh_fn = 0x62;
353 			break;
354 		case 0xfc08: case 0xfc17: case 0xfc1d: case 0xfcd1: case 0xfce0:
355 		case 0xfce2:
356 			tosh_fn = 0x68;
357 			break;
358 		default:
359 			tosh_fn = 0x00;
360 			break;
361 	}
362 
363 	return;
364 }
365 
366 
367 /*
368  * Get the machine identification number of the current model
369  */
370 static int tosh_get_machine_id(void __iomem *bios)
371 {
372 	int id;
373 	SMMRegisters regs;
374 	unsigned short bx,cx;
375 	unsigned long address;
376 
377 	id = (0x100*(int) readb(bios+0xfffe))+((int) readb(bios+0xfffa));
378 
379 	/* do we have a SCTTable machine identication number on our hands */
380 
381 	if (id==0xfc2f) {
382 
383 		/* start by getting a pointer into the BIOS */
384 
385 		regs.eax = 0xc000;
386 		regs.ebx = 0x0000;
387 		regs.ecx = 0x0000;
388 		tosh_smm(&regs);
389 		bx = (unsigned short) (regs.ebx & 0xffff);
390 
391 		/* At this point in the Toshiba routines under MS Windows
392 		   the bx register holds 0xe6f5. However my code is producing
393 		   a different value! For the time being I will just fudge the
394 		   value. This has been verified on a Satellite Pro 430CDT,
395 		   Tecra 750CDT, Tecra 780DVD and Satellite 310CDT. */
396 #if TOSH_DEBUG
397 		printk("toshiba: debugging ID ebx=0x%04x\n", regs.ebx);
398 #endif
399 		bx = 0xe6f5;
400 
401 		/* now twiddle with our pointer a bit */
402 
403 		address = bx;
404 		cx = readw(bios + address);
405 		address = 9+bx+cx;
406 		cx = readw(bios + address);
407 		address = 0xa+cx;
408 		cx = readw(bios + address);
409 
410 		/* now construct our machine identification number */
411 
412 		id = ((cx & 0xff)<<8)+((cx & 0xff00)>>8);
413 	}
414 
415 	return id;
416 }
417 
418 
419 /*
420  * Probe for the presence of a Toshiba laptop
421  *
422  *   returns and non-zero if unable to detect the presence of a Toshiba
423  *   laptop, otherwise zero and determines the Machine ID, BIOS version and
424  *   date, and SCI version.
425  */
426 static int tosh_probe(void)
427 {
428 	int i,major,minor,day,year,month,flag;
429 	unsigned char signature[7] = { 0x54,0x4f,0x53,0x48,0x49,0x42,0x41 };
430 	SMMRegisters regs;
431 	void __iomem *bios = ioremap_cache(0xf0000, 0x10000);
432 
433 	if (!bios)
434 		return -ENOMEM;
435 
436 	/* extra sanity check for the string "TOSHIBA" in the BIOS because
437 	   some machines that are not Toshiba's pass the next test */
438 
439 	for (i=0;i<7;i++) {
440 		if (readb(bios+0xe010+i)!=signature[i]) {
441 			printk("toshiba: not a supported Toshiba laptop\n");
442 			iounmap(bios);
443 			return -ENODEV;
444 		}
445 	}
446 
447 	/* call the Toshiba SCI support check routine */
448 
449 	regs.eax = 0xf0f0;
450 	regs.ebx = 0x0000;
451 	regs.ecx = 0x0000;
452 	flag = tosh_smm(&regs);
453 
454 	/* if this is not a Toshiba laptop carry flag is set and ah=0x86 */
455 
456 	if ((flag==1) || ((regs.eax & 0xff00)==0x8600)) {
457 		printk("toshiba: not a supported Toshiba laptop\n");
458 		iounmap(bios);
459 		return -ENODEV;
460 	}
461 
462 	/* if we get this far then we are running on a Toshiba (probably)! */
463 
464 	tosh_sci = regs.edx & 0xffff;
465 
466 	/* next get the machine ID of the current laptop */
467 
468 	tosh_id = tosh_get_machine_id(bios);
469 
470 	/* get the BIOS version */
471 
472 	major = readb(bios+0xe009)-'0';
473 	minor = ((readb(bios+0xe00b)-'0')*10)+(readb(bios+0xe00c)-'0');
474 	tosh_bios = (major*0x100)+minor;
475 
476 	/* get the BIOS date */
477 
478 	day = ((readb(bios+0xfff5)-'0')*10)+(readb(bios+0xfff6)-'0');
479 	month = ((readb(bios+0xfff8)-'0')*10)+(readb(bios+0xfff9)-'0');
480 	year = ((readb(bios+0xfffb)-'0')*10)+(readb(bios+0xfffc)-'0');
481 	tosh_date = (((year-90) & 0x1f)<<10) | ((month & 0xf)<<6)
482 		| ((day & 0x1f)<<1);
483 
484 
485 	/* in theory we should check the ports we are going to use for the
486 	   fn key detection (and the fan on the Portage 610/Tecra700), and
487 	   then request them to stop other drivers using them. However as
488 	   the keyboard driver grabs 0x60-0x6f and the pic driver grabs
489 	   0xa0-0xbf we can't. We just have to live dangerously and use the
490 	   ports anyway, oh boy! */
491 
492 	/* do we need to emulate the fan? */
493 
494 	if ((tosh_id==0xfccb) || (tosh_id==0xfccc))
495 		tosh_fan = 1;
496 
497 	iounmap(bios);
498 
499 	return 0;
500 }
501 
502 static int __init toshiba_init(void)
503 {
504 	int retval;
505 	/* are we running on a Toshiba laptop */
506 
507 	if (tosh_probe())
508 		return -ENODEV;
509 
510 	printk(KERN_INFO "Toshiba System Management Mode driver v" TOSH_VERSION "\n");
511 
512 	/* set the port to use for Fn status if not specified as a parameter */
513 	if (tosh_fn==0x00)
514 		tosh_set_fn_port();
515 
516 	/* register the device file */
517 	retval = misc_register(&tosh_device);
518 	if (retval < 0)
519 		return retval;
520 
521 #ifdef CONFIG_PROC_FS
522 	{
523 		struct proc_dir_entry *pde;
524 
525 		pde = proc_create("toshiba", 0, NULL, &proc_toshiba_fops);
526 		if (!pde) {
527 			misc_deregister(&tosh_device);
528 			return -ENOMEM;
529 		}
530 	}
531 #endif
532 
533 	return 0;
534 }
535 
536 static void __exit toshiba_exit(void)
537 {
538 	remove_proc_entry("toshiba", NULL);
539 	misc_deregister(&tosh_device);
540 }
541 
542 module_init(toshiba_init);
543 module_exit(toshiba_exit);
544 
545