xref: /openbmc/linux/drivers/pnp/isapnp/core.c (revision a1e58bbd)
1 /*
2  *  ISA Plug & Play support
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19  *
20  *  Changelog:
21  *  2000-01-01	Added quirks handling for buggy hardware
22  *		Peter Denison <peterd@pnd-pc.demon.co.uk>
23  *  2000-06-14	Added isapnp_probe_devs() and isapnp_activate_dev()
24  *		Christoph Hellwig <hch@infradead.org>
25  *  2001-06-03  Added release_region calls to correspond with
26  *		request_region calls when a failure occurs.  Also
27  *		added KERN_* constants to printk() calls.
28  *  2001-11-07  Added isapnp_{,un}register_driver calls along the lines
29  *              of the pci driver interface
30  *              Kai Germaschewski <kai.germaschewski@gmx.de>
31  *  2002-06-06  Made the use of dma channel 0 configurable
32  *              Gerald Teschl <gerald.teschl@univie.ac.at>
33  *  2002-10-06  Ported to PnP Layer - Adam Belay <ambx1@neo.rr.com>
34  *  2003-08-11	Resource Management Updates - Adam Belay <ambx1@neo.rr.com>
35  */
36 
37 #include <linux/module.h>
38 #include <linux/kernel.h>
39 #include <linux/errno.h>
40 #include <linux/slab.h>
41 #include <linux/delay.h>
42 #include <linux/init.h>
43 #include <linux/isapnp.h>
44 #include <linux/mutex.h>
45 #include <asm/io.h>
46 
47 #if 0
48 #define ISAPNP_REGION_OK
49 #endif
50 
51 int isapnp_disable;		/* Disable ISA PnP */
52 static int isapnp_rdp;		/* Read Data Port */
53 static int isapnp_reset = 1;	/* reset all PnP cards (deactivate) */
54 static int isapnp_verbose = 1;	/* verbose mode */
55 
56 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
57 MODULE_DESCRIPTION("Generic ISA Plug & Play support");
58 module_param(isapnp_disable, int, 0);
59 MODULE_PARM_DESC(isapnp_disable, "ISA Plug & Play disable");
60 module_param(isapnp_rdp, int, 0);
61 MODULE_PARM_DESC(isapnp_rdp, "ISA Plug & Play read data port");
62 module_param(isapnp_reset, int, 0);
63 MODULE_PARM_DESC(isapnp_reset, "ISA Plug & Play reset all cards");
64 module_param(isapnp_verbose, int, 0);
65 MODULE_PARM_DESC(isapnp_verbose, "ISA Plug & Play verbose mode");
66 MODULE_LICENSE("GPL");
67 
68 #define _PIDXR		0x279
69 #define _PNPWRP		0xa79
70 
71 /* short tags */
72 #define _STAG_PNPVERNO		0x01
73 #define _STAG_LOGDEVID		0x02
74 #define _STAG_COMPATDEVID	0x03
75 #define _STAG_IRQ		0x04
76 #define _STAG_DMA		0x05
77 #define _STAG_STARTDEP		0x06
78 #define _STAG_ENDDEP		0x07
79 #define _STAG_IOPORT		0x08
80 #define _STAG_FIXEDIO		0x09
81 #define _STAG_VENDOR		0x0e
82 #define _STAG_END		0x0f
83 /* long tags */
84 #define _LTAG_MEMRANGE		0x81
85 #define _LTAG_ANSISTR		0x82
86 #define _LTAG_UNICODESTR	0x83
87 #define _LTAG_VENDOR		0x84
88 #define _LTAG_MEM32RANGE	0x85
89 #define _LTAG_FIXEDMEM32RANGE	0x86
90 
91 /*
92  * Sizes of ISAPNP logical device configuration register sets.
93  * See PNP-ISA-v1.0a.pdf, Appendix A.
94  */
95 #define ISAPNP_MAX_MEM		4
96 #define ISAPNP_MAX_PORT		8
97 #define ISAPNP_MAX_IRQ		2
98 #define ISAPNP_MAX_DMA		2
99 
100 static unsigned char isapnp_checksum_value;
101 static DEFINE_MUTEX(isapnp_cfg_mutex);
102 static int isapnp_csn_count;
103 
104 /* some prototypes */
105 
106 static inline void write_data(unsigned char x)
107 {
108 	outb(x, _PNPWRP);
109 }
110 
111 static inline void write_address(unsigned char x)
112 {
113 	outb(x, _PIDXR);
114 	udelay(20);
115 }
116 
117 static inline unsigned char read_data(void)
118 {
119 	unsigned char val = inb(isapnp_rdp);
120 	return val;
121 }
122 
123 unsigned char isapnp_read_byte(unsigned char idx)
124 {
125 	write_address(idx);
126 	return read_data();
127 }
128 
129 static unsigned short isapnp_read_word(unsigned char idx)
130 {
131 	unsigned short val;
132 
133 	val = isapnp_read_byte(idx);
134 	val = (val << 8) + isapnp_read_byte(idx + 1);
135 	return val;
136 }
137 
138 void isapnp_write_byte(unsigned char idx, unsigned char val)
139 {
140 	write_address(idx);
141 	write_data(val);
142 }
143 
144 static void isapnp_write_word(unsigned char idx, unsigned short val)
145 {
146 	isapnp_write_byte(idx, val >> 8);
147 	isapnp_write_byte(idx + 1, val);
148 }
149 
150 static void isapnp_key(void)
151 {
152 	unsigned char code = 0x6a, msb;
153 	int i;
154 
155 	mdelay(1);
156 	write_address(0x00);
157 	write_address(0x00);
158 
159 	write_address(code);
160 
161 	for (i = 1; i < 32; i++) {
162 		msb = ((code & 0x01) ^ ((code & 0x02) >> 1)) << 7;
163 		code = (code >> 1) | msb;
164 		write_address(code);
165 	}
166 }
167 
168 /* place all pnp cards in wait-for-key state */
169 static void isapnp_wait(void)
170 {
171 	isapnp_write_byte(0x02, 0x02);
172 }
173 
174 static void isapnp_wake(unsigned char csn)
175 {
176 	isapnp_write_byte(0x03, csn);
177 }
178 
179 static void isapnp_device(unsigned char logdev)
180 {
181 	isapnp_write_byte(0x07, logdev);
182 }
183 
184 static void isapnp_activate(unsigned char logdev)
185 {
186 	isapnp_device(logdev);
187 	isapnp_write_byte(ISAPNP_CFG_ACTIVATE, 1);
188 	udelay(250);
189 }
190 
191 static void isapnp_deactivate(unsigned char logdev)
192 {
193 	isapnp_device(logdev);
194 	isapnp_write_byte(ISAPNP_CFG_ACTIVATE, 0);
195 	udelay(500);
196 }
197 
198 static void __init isapnp_peek(unsigned char *data, int bytes)
199 {
200 	int i, j;
201 	unsigned char d = 0;
202 
203 	for (i = 1; i <= bytes; i++) {
204 		for (j = 0; j < 20; j++) {
205 			d = isapnp_read_byte(0x05);
206 			if (d & 1)
207 				break;
208 			udelay(100);
209 		}
210 		if (!(d & 1)) {
211 			if (data != NULL)
212 				*data++ = 0xff;
213 			continue;
214 		}
215 		d = isapnp_read_byte(0x04);	/* PRESDI */
216 		isapnp_checksum_value += d;
217 		if (data != NULL)
218 			*data++ = d;
219 	}
220 }
221 
222 #define RDP_STEP	32	/* minimum is 4 */
223 
224 static int isapnp_next_rdp(void)
225 {
226 	int rdp = isapnp_rdp;
227 	static int old_rdp = 0;
228 
229 	if (old_rdp) {
230 		release_region(old_rdp, 1);
231 		old_rdp = 0;
232 	}
233 	while (rdp <= 0x3ff) {
234 		/*
235 		 *      We cannot use NE2000 probe spaces for ISAPnP or we
236 		 *      will lock up machines.
237 		 */
238 		if ((rdp < 0x280 || rdp > 0x380)
239 		    && request_region(rdp, 1, "ISAPnP")) {
240 			isapnp_rdp = rdp;
241 			old_rdp = rdp;
242 			return 0;
243 		}
244 		rdp += RDP_STEP;
245 	}
246 	return -1;
247 }
248 
249 /* Set read port address */
250 static inline void isapnp_set_rdp(void)
251 {
252 	isapnp_write_byte(0x00, isapnp_rdp >> 2);
253 	udelay(100);
254 }
255 
256 /*
257  *	Perform an isolation. The port selection code now tries to avoid
258  *	"dangerous to read" ports.
259  */
260 static int __init isapnp_isolate_rdp_select(void)
261 {
262 	isapnp_wait();
263 	isapnp_key();
264 
265 	/* Control: reset CSN and conditionally everything else too */
266 	isapnp_write_byte(0x02, isapnp_reset ? 0x05 : 0x04);
267 	mdelay(2);
268 
269 	isapnp_wait();
270 	isapnp_key();
271 	isapnp_wake(0x00);
272 
273 	if (isapnp_next_rdp() < 0) {
274 		isapnp_wait();
275 		return -1;
276 	}
277 
278 	isapnp_set_rdp();
279 	udelay(1000);
280 	write_address(0x01);
281 	udelay(1000);
282 	return 0;
283 }
284 
285 /*
286  *  Isolate (assign uniqued CSN) to all ISA PnP devices.
287  */
288 static int __init isapnp_isolate(void)
289 {
290 	unsigned char checksum = 0x6a;
291 	unsigned char chksum = 0x00;
292 	unsigned char bit = 0x00;
293 	int data;
294 	int csn = 0;
295 	int i;
296 	int iteration = 1;
297 
298 	isapnp_rdp = 0x213;
299 	if (isapnp_isolate_rdp_select() < 0)
300 		return -1;
301 
302 	while (1) {
303 		for (i = 1; i <= 64; i++) {
304 			data = read_data() << 8;
305 			udelay(250);
306 			data = data | read_data();
307 			udelay(250);
308 			if (data == 0x55aa)
309 				bit = 0x01;
310 			checksum =
311 			    ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7)
312 			    | (checksum >> 1);
313 			bit = 0x00;
314 		}
315 		for (i = 65; i <= 72; i++) {
316 			data = read_data() << 8;
317 			udelay(250);
318 			data = data | read_data();
319 			udelay(250);
320 			if (data == 0x55aa)
321 				chksum |= (1 << (i - 65));
322 		}
323 		if (checksum != 0x00 && checksum == chksum) {
324 			csn++;
325 
326 			isapnp_write_byte(0x06, csn);
327 			udelay(250);
328 			iteration++;
329 			isapnp_wake(0x00);
330 			isapnp_set_rdp();
331 			udelay(1000);
332 			write_address(0x01);
333 			udelay(1000);
334 			goto __next;
335 		}
336 		if (iteration == 1) {
337 			isapnp_rdp += RDP_STEP;
338 			if (isapnp_isolate_rdp_select() < 0)
339 				return -1;
340 		} else if (iteration > 1) {
341 			break;
342 		}
343 __next:
344 		if (csn == 255)
345 			break;
346 		checksum = 0x6a;
347 		chksum = 0x00;
348 		bit = 0x00;
349 	}
350 	isapnp_wait();
351 	isapnp_csn_count = csn;
352 	return csn;
353 }
354 
355 /*
356  *  Read one tag from stream.
357  */
358 static int __init isapnp_read_tag(unsigned char *type, unsigned short *size)
359 {
360 	unsigned char tag, tmp[2];
361 
362 	isapnp_peek(&tag, 1);
363 	if (tag == 0)		/* invalid tag */
364 		return -1;
365 	if (tag & 0x80) {	/* large item */
366 		*type = tag;
367 		isapnp_peek(tmp, 2);
368 		*size = (tmp[1] << 8) | tmp[0];
369 	} else {
370 		*type = (tag >> 3) & 0x0f;
371 		*size = tag & 0x07;
372 	}
373 #if 0
374 	printk(KERN_DEBUG "tag = 0x%x, type = 0x%x, size = %i\n", tag, *type,
375 	       *size);
376 #endif
377 	if (*type == 0xff && *size == 0xffff)	/* probably invalid data */
378 		return -1;
379 	return 0;
380 }
381 
382 /*
383  *  Skip specified number of bytes from stream.
384  */
385 static void __init isapnp_skip_bytes(int count)
386 {
387 	isapnp_peek(NULL, count);
388 }
389 
390 /*
391  *  Parse EISA id.
392  */
393 static void isapnp_parse_id(struct pnp_dev *dev, unsigned short vendor,
394 			    unsigned short device)
395 {
396 	struct pnp_id *id;
397 
398 	if (!dev)
399 		return;
400 	id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
401 	if (!id)
402 		return;
403 	sprintf(id->id, "%c%c%c%x%x%x%x",
404 		'A' + ((vendor >> 2) & 0x3f) - 1,
405 		'A' + (((vendor & 3) << 3) | ((vendor >> 13) & 7)) - 1,
406 		'A' + ((vendor >> 8) & 0x1f) - 1,
407 		(device >> 4) & 0x0f,
408 		device & 0x0f, (device >> 12) & 0x0f, (device >> 8) & 0x0f);
409 	pnp_add_id(id, dev);
410 }
411 
412 /*
413  *  Parse logical device tag.
414  */
415 static struct pnp_dev *__init isapnp_parse_device(struct pnp_card *card,
416 						  int size, int number)
417 {
418 	unsigned char tmp[6];
419 	struct pnp_dev *dev;
420 
421 	isapnp_peek(tmp, size);
422 	dev = kzalloc(sizeof(struct pnp_dev), GFP_KERNEL);
423 	if (!dev)
424 		return NULL;
425 	dev->number = number;
426 	isapnp_parse_id(dev, (tmp[1] << 8) | tmp[0], (tmp[3] << 8) | tmp[2]);
427 	dev->regs = tmp[4];
428 	dev->card = card;
429 	if (size > 5)
430 		dev->regs |= tmp[5] << 8;
431 	dev->protocol = &isapnp_protocol;
432 	dev->capabilities |= PNP_CONFIGURABLE;
433 	dev->capabilities |= PNP_READ;
434 	dev->capabilities |= PNP_WRITE;
435 	dev->capabilities |= PNP_DISABLE;
436 	pnp_init_resource_table(&dev->res);
437 	return dev;
438 }
439 
440 /*
441  *  Add IRQ resource to resources list.
442  */
443 static void __init isapnp_parse_irq_resource(struct pnp_option *option,
444 					     int size)
445 {
446 	unsigned char tmp[3];
447 	struct pnp_irq *irq;
448 	unsigned long bits;
449 
450 	isapnp_peek(tmp, size);
451 	irq = kzalloc(sizeof(struct pnp_irq), GFP_KERNEL);
452 	if (!irq)
453 		return;
454 	bits = (tmp[1] << 8) | tmp[0];
455 	bitmap_copy(irq->map, &bits, 16);
456 	if (size > 2)
457 		irq->flags = tmp[2];
458 	else
459 		irq->flags = IORESOURCE_IRQ_HIGHEDGE;
460 	pnp_register_irq_resource(option, irq);
461 }
462 
463 /*
464  *  Add DMA resource to resources list.
465  */
466 static void __init isapnp_parse_dma_resource(struct pnp_option *option,
467 					     int size)
468 {
469 	unsigned char tmp[2];
470 	struct pnp_dma *dma;
471 
472 	isapnp_peek(tmp, size);
473 	dma = kzalloc(sizeof(struct pnp_dma), GFP_KERNEL);
474 	if (!dma)
475 		return;
476 	dma->map = tmp[0];
477 	dma->flags = tmp[1];
478 	pnp_register_dma_resource(option, dma);
479 }
480 
481 /*
482  *  Add port resource to resources list.
483  */
484 static void __init isapnp_parse_port_resource(struct pnp_option *option,
485 					      int size)
486 {
487 	unsigned char tmp[7];
488 	struct pnp_port *port;
489 
490 	isapnp_peek(tmp, size);
491 	port = kzalloc(sizeof(struct pnp_port), GFP_KERNEL);
492 	if (!port)
493 		return;
494 	port->min = (tmp[2] << 8) | tmp[1];
495 	port->max = (tmp[4] << 8) | tmp[3];
496 	port->align = tmp[5];
497 	port->size = tmp[6];
498 	port->flags = tmp[0] ? PNP_PORT_FLAG_16BITADDR : 0;
499 	pnp_register_port_resource(option, port);
500 }
501 
502 /*
503  *  Add fixed port resource to resources list.
504  */
505 static void __init isapnp_parse_fixed_port_resource(struct pnp_option *option,
506 						    int size)
507 {
508 	unsigned char tmp[3];
509 	struct pnp_port *port;
510 
511 	isapnp_peek(tmp, size);
512 	port = kzalloc(sizeof(struct pnp_port), GFP_KERNEL);
513 	if (!port)
514 		return;
515 	port->min = port->max = (tmp[1] << 8) | tmp[0];
516 	port->size = tmp[2];
517 	port->align = 0;
518 	port->flags = PNP_PORT_FLAG_FIXED;
519 	pnp_register_port_resource(option, port);
520 }
521 
522 /*
523  *  Add memory resource to resources list.
524  */
525 static void __init isapnp_parse_mem_resource(struct pnp_option *option,
526 					     int size)
527 {
528 	unsigned char tmp[9];
529 	struct pnp_mem *mem;
530 
531 	isapnp_peek(tmp, size);
532 	mem = kzalloc(sizeof(struct pnp_mem), GFP_KERNEL);
533 	if (!mem)
534 		return;
535 	mem->min = ((tmp[2] << 8) | tmp[1]) << 8;
536 	mem->max = ((tmp[4] << 8) | tmp[3]) << 8;
537 	mem->align = (tmp[6] << 8) | tmp[5];
538 	mem->size = ((tmp[8] << 8) | tmp[7]) << 8;
539 	mem->flags = tmp[0];
540 	pnp_register_mem_resource(option, mem);
541 }
542 
543 /*
544  *  Add 32-bit memory resource to resources list.
545  */
546 static void __init isapnp_parse_mem32_resource(struct pnp_option *option,
547 					       int size)
548 {
549 	unsigned char tmp[17];
550 	struct pnp_mem *mem;
551 
552 	isapnp_peek(tmp, size);
553 	mem = kzalloc(sizeof(struct pnp_mem), GFP_KERNEL);
554 	if (!mem)
555 		return;
556 	mem->min = (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
557 	mem->max = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5];
558 	mem->align =
559 	    (tmp[12] << 24) | (tmp[11] << 16) | (tmp[10] << 8) | tmp[9];
560 	mem->size =
561 	    (tmp[16] << 24) | (tmp[15] << 16) | (tmp[14] << 8) | tmp[13];
562 	mem->flags = tmp[0];
563 	pnp_register_mem_resource(option, mem);
564 }
565 
566 /*
567  *  Add 32-bit fixed memory resource to resources list.
568  */
569 static void __init isapnp_parse_fixed_mem32_resource(struct pnp_option *option,
570 						     int size)
571 {
572 	unsigned char tmp[9];
573 	struct pnp_mem *mem;
574 
575 	isapnp_peek(tmp, size);
576 	mem = kzalloc(sizeof(struct pnp_mem), GFP_KERNEL);
577 	if (!mem)
578 		return;
579 	mem->min = mem->max =
580 	    (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
581 	mem->size = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5];
582 	mem->align = 0;
583 	mem->flags = tmp[0];
584 	pnp_register_mem_resource(option, mem);
585 }
586 
587 /*
588  *  Parse card name for ISA PnP device.
589  */
590 static void __init
591 isapnp_parse_name(char *name, unsigned int name_max, unsigned short *size)
592 {
593 	if (name[0] == '\0') {
594 		unsigned short size1 =
595 		    *size >= name_max ? (name_max - 1) : *size;
596 		isapnp_peek(name, size1);
597 		name[size1] = '\0';
598 		*size -= size1;
599 
600 		/* clean whitespace from end of string */
601 		while (size1 > 0 && name[--size1] == ' ')
602 			name[size1] = '\0';
603 	}
604 }
605 
606 /*
607  *  Parse resource map for logical device.
608  */
609 static int __init isapnp_create_device(struct pnp_card *card,
610 				       unsigned short size)
611 {
612 	int number = 0, skip = 0, priority = 0, compat = 0;
613 	unsigned char type, tmp[17];
614 	struct pnp_option *option;
615 	struct pnp_dev *dev;
616 
617 	if ((dev = isapnp_parse_device(card, size, number++)) == NULL)
618 		return 1;
619 	option = pnp_register_independent_option(dev);
620 	if (!option) {
621 		kfree(dev);
622 		return 1;
623 	}
624 	pnp_add_card_device(card, dev);
625 
626 	while (1) {
627 		if (isapnp_read_tag(&type, &size) < 0)
628 			return 1;
629 		if (skip && type != _STAG_LOGDEVID && type != _STAG_END)
630 			goto __skip;
631 		switch (type) {
632 		case _STAG_LOGDEVID:
633 			if (size >= 5 && size <= 6) {
634 				if ((dev =
635 				     isapnp_parse_device(card, size,
636 							 number++)) == NULL)
637 					return 1;
638 				size = 0;
639 				skip = 0;
640 				option = pnp_register_independent_option(dev);
641 				if (!option) {
642 					kfree(dev);
643 					return 1;
644 				}
645 				pnp_add_card_device(card, dev);
646 			} else {
647 				skip = 1;
648 			}
649 			priority = 0;
650 			compat = 0;
651 			break;
652 		case _STAG_COMPATDEVID:
653 			if (size == 4 && compat < DEVICE_COUNT_COMPATIBLE) {
654 				isapnp_peek(tmp, 4);
655 				isapnp_parse_id(dev, (tmp[1] << 8) | tmp[0],
656 						(tmp[3] << 8) | tmp[2]);
657 				compat++;
658 				size = 0;
659 			}
660 			break;
661 		case _STAG_IRQ:
662 			if (size < 2 || size > 3)
663 				goto __skip;
664 			isapnp_parse_irq_resource(option, size);
665 			size = 0;
666 			break;
667 		case _STAG_DMA:
668 			if (size != 2)
669 				goto __skip;
670 			isapnp_parse_dma_resource(option, size);
671 			size = 0;
672 			break;
673 		case _STAG_STARTDEP:
674 			if (size > 1)
675 				goto __skip;
676 			priority = 0x100 | PNP_RES_PRIORITY_ACCEPTABLE;
677 			if (size > 0) {
678 				isapnp_peek(tmp, size);
679 				priority = 0x100 | tmp[0];
680 				size = 0;
681 			}
682 			option = pnp_register_dependent_option(dev, priority);
683 			if (!option)
684 				return 1;
685 			break;
686 		case _STAG_ENDDEP:
687 			if (size != 0)
688 				goto __skip;
689 			priority = 0;
690 			break;
691 		case _STAG_IOPORT:
692 			if (size != 7)
693 				goto __skip;
694 			isapnp_parse_port_resource(option, size);
695 			size = 0;
696 			break;
697 		case _STAG_FIXEDIO:
698 			if (size != 3)
699 				goto __skip;
700 			isapnp_parse_fixed_port_resource(option, size);
701 			size = 0;
702 			break;
703 		case _STAG_VENDOR:
704 			break;
705 		case _LTAG_MEMRANGE:
706 			if (size != 9)
707 				goto __skip;
708 			isapnp_parse_mem_resource(option, size);
709 			size = 0;
710 			break;
711 		case _LTAG_ANSISTR:
712 			isapnp_parse_name(dev->name, sizeof(dev->name), &size);
713 			break;
714 		case _LTAG_UNICODESTR:
715 			/* silently ignore */
716 			/* who use unicode for hardware identification? */
717 			break;
718 		case _LTAG_VENDOR:
719 			break;
720 		case _LTAG_MEM32RANGE:
721 			if (size != 17)
722 				goto __skip;
723 			isapnp_parse_mem32_resource(option, size);
724 			size = 0;
725 			break;
726 		case _LTAG_FIXEDMEM32RANGE:
727 			if (size != 9)
728 				goto __skip;
729 			isapnp_parse_fixed_mem32_resource(option, size);
730 			size = 0;
731 			break;
732 		case _STAG_END:
733 			if (size > 0)
734 				isapnp_skip_bytes(size);
735 			return 1;
736 		default:
737 			printk(KERN_ERR
738 			       "isapnp: unexpected or unknown tag type 0x%x for logical device %i (device %i), ignored\n",
739 			       type, dev->number, card->number);
740 		}
741 __skip:
742 		if (size > 0)
743 			isapnp_skip_bytes(size);
744 	}
745 	return 0;
746 }
747 
748 /*
749  *  Parse resource map for ISA PnP card.
750  */
751 static void __init isapnp_parse_resource_map(struct pnp_card *card)
752 {
753 	unsigned char type, tmp[17];
754 	unsigned short size;
755 
756 	while (1) {
757 		if (isapnp_read_tag(&type, &size) < 0)
758 			return;
759 		switch (type) {
760 		case _STAG_PNPVERNO:
761 			if (size != 2)
762 				goto __skip;
763 			isapnp_peek(tmp, 2);
764 			card->pnpver = tmp[0];
765 			card->productver = tmp[1];
766 			size = 0;
767 			break;
768 		case _STAG_LOGDEVID:
769 			if (size >= 5 && size <= 6) {
770 				if (isapnp_create_device(card, size) == 1)
771 					return;
772 				size = 0;
773 			}
774 			break;
775 		case _STAG_VENDOR:
776 			break;
777 		case _LTAG_ANSISTR:
778 			isapnp_parse_name(card->name, sizeof(card->name),
779 					  &size);
780 			break;
781 		case _LTAG_UNICODESTR:
782 			/* silently ignore */
783 			/* who use unicode for hardware identification? */
784 			break;
785 		case _LTAG_VENDOR:
786 			break;
787 		case _STAG_END:
788 			if (size > 0)
789 				isapnp_skip_bytes(size);
790 			return;
791 		default:
792 			printk(KERN_ERR
793 			       "isapnp: unexpected or unknown tag type 0x%x for device %i, ignored\n",
794 			       type, card->number);
795 		}
796 __skip:
797 		if (size > 0)
798 			isapnp_skip_bytes(size);
799 	}
800 }
801 
802 /*
803  *  Compute ISA PnP checksum for first eight bytes.
804  */
805 static unsigned char __init isapnp_checksum(unsigned char *data)
806 {
807 	int i, j;
808 	unsigned char checksum = 0x6a, bit, b;
809 
810 	for (i = 0; i < 8; i++) {
811 		b = data[i];
812 		for (j = 0; j < 8; j++) {
813 			bit = 0;
814 			if (b & (1 << j))
815 				bit = 1;
816 			checksum =
817 			    ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7)
818 			    | (checksum >> 1);
819 		}
820 	}
821 	return checksum;
822 }
823 
824 /*
825  *  Parse EISA id for ISA PnP card.
826  */
827 static void isapnp_parse_card_id(struct pnp_card *card, unsigned short vendor,
828 				 unsigned short device)
829 {
830 	struct pnp_id *id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
831 
832 	if (!id)
833 		return;
834 	sprintf(id->id, "%c%c%c%x%x%x%x",
835 		'A' + ((vendor >> 2) & 0x3f) - 1,
836 		'A' + (((vendor & 3) << 3) | ((vendor >> 13) & 7)) - 1,
837 		'A' + ((vendor >> 8) & 0x1f) - 1,
838 		(device >> 4) & 0x0f,
839 		device & 0x0f, (device >> 12) & 0x0f, (device >> 8) & 0x0f);
840 	pnp_add_card_id(id, card);
841 }
842 
843 /*
844  *  Build device list for all present ISA PnP devices.
845  */
846 static int __init isapnp_build_device_list(void)
847 {
848 	int csn;
849 	unsigned char header[9], checksum;
850 	struct pnp_card *card;
851 
852 	isapnp_wait();
853 	isapnp_key();
854 	for (csn = 1; csn <= isapnp_csn_count; csn++) {
855 		isapnp_wake(csn);
856 		isapnp_peek(header, 9);
857 		checksum = isapnp_checksum(header);
858 #if 0
859 		printk(KERN_DEBUG
860 		       "vendor: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
861 		       header[0], header[1], header[2], header[3], header[4],
862 		       header[5], header[6], header[7], header[8]);
863 		printk(KERN_DEBUG "checksum = 0x%x\n", checksum);
864 #endif
865 		if ((card =
866 		     kzalloc(sizeof(struct pnp_card), GFP_KERNEL)) == NULL)
867 			continue;
868 
869 		card->number = csn;
870 		INIT_LIST_HEAD(&card->devices);
871 		isapnp_parse_card_id(card, (header[1] << 8) | header[0],
872 				     (header[3] << 8) | header[2]);
873 		card->serial =
874 		    (header[7] << 24) | (header[6] << 16) | (header[5] << 8) |
875 		    header[4];
876 		isapnp_checksum_value = 0x00;
877 		isapnp_parse_resource_map(card);
878 		if (isapnp_checksum_value != 0x00)
879 			printk(KERN_ERR
880 			       "isapnp: checksum for device %i is not valid (0x%x)\n",
881 			       csn, isapnp_checksum_value);
882 		card->checksum = isapnp_checksum_value;
883 		card->protocol = &isapnp_protocol;
884 
885 		pnp_add_card(card);
886 	}
887 	isapnp_wait();
888 	return 0;
889 }
890 
891 /*
892  *  Basic configuration routines.
893  */
894 
895 int isapnp_present(void)
896 {
897 	struct pnp_card *card;
898 
899 	pnp_for_each_card(card) {
900 		if (card->protocol == &isapnp_protocol)
901 			return 1;
902 	}
903 	return 0;
904 }
905 
906 int isapnp_cfg_begin(int csn, int logdev)
907 {
908 	if (csn < 1 || csn > isapnp_csn_count || logdev > 10)
909 		return -EINVAL;
910 	mutex_lock(&isapnp_cfg_mutex);
911 	isapnp_wait();
912 	isapnp_key();
913 	isapnp_wake(csn);
914 #if 0
915 	/* to avoid malfunction when the isapnptools package is used */
916 	/* we must set RDP to our value again */
917 	/* it is possible to set RDP only in the isolation phase */
918 	/*   Jens Thoms Toerring <Jens.Toerring@physik.fu-berlin.de> */
919 	isapnp_write_byte(0x02, 0x04);	/* clear CSN of card */
920 	mdelay(2);		/* is this necessary? */
921 	isapnp_wake(csn);	/* bring card into sleep state */
922 	isapnp_wake(0);		/* bring card into isolation state */
923 	isapnp_set_rdp();	/* reset the RDP port */
924 	udelay(1000);		/* delay 1000us */
925 	isapnp_write_byte(0x06, csn);	/* reset CSN to previous value */
926 	udelay(250);		/* is this necessary? */
927 #endif
928 	if (logdev >= 0)
929 		isapnp_device(logdev);
930 	return 0;
931 }
932 
933 int isapnp_cfg_end(void)
934 {
935 	isapnp_wait();
936 	mutex_unlock(&isapnp_cfg_mutex);
937 	return 0;
938 }
939 
940 /*
941  *  Initialization.
942  */
943 
944 EXPORT_SYMBOL(isapnp_protocol);
945 EXPORT_SYMBOL(isapnp_present);
946 EXPORT_SYMBOL(isapnp_cfg_begin);
947 EXPORT_SYMBOL(isapnp_cfg_end);
948 EXPORT_SYMBOL(isapnp_write_byte);
949 
950 static int isapnp_read_resources(struct pnp_dev *dev,
951 				 struct pnp_resource_table *res)
952 {
953 	int tmp, ret;
954 
955 	dev->active = isapnp_read_byte(ISAPNP_CFG_ACTIVATE);
956 	if (dev->active) {
957 		for (tmp = 0; tmp < ISAPNP_MAX_PORT; tmp++) {
958 			ret = isapnp_read_word(ISAPNP_CFG_PORT + (tmp << 1));
959 			if (!ret)
960 				continue;
961 			res->port_resource[tmp].start = ret;
962 			res->port_resource[tmp].flags = IORESOURCE_IO;
963 		}
964 		for (tmp = 0; tmp < ISAPNP_MAX_MEM; tmp++) {
965 			ret =
966 			    isapnp_read_word(ISAPNP_CFG_MEM + (tmp << 3)) << 8;
967 			if (!ret)
968 				continue;
969 			res->mem_resource[tmp].start = ret;
970 			res->mem_resource[tmp].flags = IORESOURCE_MEM;
971 		}
972 		for (tmp = 0; tmp < ISAPNP_MAX_IRQ; tmp++) {
973 			ret =
974 			    (isapnp_read_word(ISAPNP_CFG_IRQ + (tmp << 1)) >>
975 			     8);
976 			if (!ret)
977 				continue;
978 			res->irq_resource[tmp].start =
979 			    res->irq_resource[tmp].end = ret;
980 			res->irq_resource[tmp].flags = IORESOURCE_IRQ;
981 		}
982 		for (tmp = 0; tmp < ISAPNP_MAX_DMA; tmp++) {
983 			ret = isapnp_read_byte(ISAPNP_CFG_DMA + tmp);
984 			if (ret == 4)
985 				continue;
986 			res->dma_resource[tmp].start =
987 			    res->dma_resource[tmp].end = ret;
988 			res->dma_resource[tmp].flags = IORESOURCE_DMA;
989 		}
990 	}
991 	return 0;
992 }
993 
994 static int isapnp_get_resources(struct pnp_dev *dev,
995 				struct pnp_resource_table *res)
996 {
997 	int ret;
998 
999 	pnp_init_resource_table(res);
1000 	isapnp_cfg_begin(dev->card->number, dev->number);
1001 	ret = isapnp_read_resources(dev, res);
1002 	isapnp_cfg_end();
1003 	return ret;
1004 }
1005 
1006 static int isapnp_set_resources(struct pnp_dev *dev,
1007 				struct pnp_resource_table *res)
1008 {
1009 	int tmp;
1010 
1011 	isapnp_cfg_begin(dev->card->number, dev->number);
1012 	dev->active = 1;
1013 	for (tmp = 0;
1014 	     tmp < ISAPNP_MAX_PORT
1015 	     && (res->port_resource[tmp].
1016 		 flags & (IORESOURCE_IO | IORESOURCE_UNSET)) == IORESOURCE_IO;
1017 	     tmp++)
1018 		isapnp_write_word(ISAPNP_CFG_PORT + (tmp << 1),
1019 				  res->port_resource[tmp].start);
1020 	for (tmp = 0;
1021 	     tmp < ISAPNP_MAX_IRQ
1022 	     && (res->irq_resource[tmp].
1023 		 flags & (IORESOURCE_IRQ | IORESOURCE_UNSET)) == IORESOURCE_IRQ;
1024 	     tmp++) {
1025 		int irq = res->irq_resource[tmp].start;
1026 		if (irq == 2)
1027 			irq = 9;
1028 		isapnp_write_byte(ISAPNP_CFG_IRQ + (tmp << 1), irq);
1029 	}
1030 	for (tmp = 0;
1031 	     tmp < ISAPNP_MAX_DMA
1032 	     && (res->dma_resource[tmp].
1033 		 flags & (IORESOURCE_DMA | IORESOURCE_UNSET)) == IORESOURCE_DMA;
1034 	     tmp++)
1035 		isapnp_write_byte(ISAPNP_CFG_DMA + tmp,
1036 				  res->dma_resource[tmp].start);
1037 	for (tmp = 0;
1038 	     tmp < ISAPNP_MAX_MEM
1039 	     && (res->mem_resource[tmp].
1040 		 flags & (IORESOURCE_MEM | IORESOURCE_UNSET)) == IORESOURCE_MEM;
1041 	     tmp++)
1042 		isapnp_write_word(ISAPNP_CFG_MEM + (tmp << 3),
1043 				  (res->mem_resource[tmp].start >> 8) & 0xffff);
1044 	/* FIXME: We aren't handling 32bit mems properly here */
1045 	isapnp_activate(dev->number);
1046 	isapnp_cfg_end();
1047 	return 0;
1048 }
1049 
1050 static int isapnp_disable_resources(struct pnp_dev *dev)
1051 {
1052 	if (!dev->active)
1053 		return -EINVAL;
1054 	isapnp_cfg_begin(dev->card->number, dev->number);
1055 	isapnp_deactivate(dev->number);
1056 	dev->active = 0;
1057 	isapnp_cfg_end();
1058 	return 0;
1059 }
1060 
1061 struct pnp_protocol isapnp_protocol = {
1062 	.name = "ISA Plug and Play",
1063 	.get = isapnp_get_resources,
1064 	.set = isapnp_set_resources,
1065 	.disable = isapnp_disable_resources,
1066 };
1067 
1068 static int __init isapnp_init(void)
1069 {
1070 	int cards;
1071 	struct pnp_card *card;
1072 	struct pnp_dev *dev;
1073 
1074 	if (isapnp_disable) {
1075 		printk(KERN_INFO "isapnp: ISA Plug & Play support disabled\n");
1076 		return 0;
1077 	}
1078 #ifdef CONFIG_PPC_MERGE
1079 	if (check_legacy_ioport(_PIDXR) || check_legacy_ioport(_PNPWRP))
1080 		return -EINVAL;
1081 #endif
1082 #ifdef ISAPNP_REGION_OK
1083 	if (!request_region(_PIDXR, 1, "isapnp index")) {
1084 		printk(KERN_ERR "isapnp: Index Register 0x%x already used\n",
1085 		       _PIDXR);
1086 		return -EBUSY;
1087 	}
1088 #endif
1089 	if (!request_region(_PNPWRP, 1, "isapnp write")) {
1090 		printk(KERN_ERR
1091 		       "isapnp: Write Data Register 0x%x already used\n",
1092 		       _PNPWRP);
1093 #ifdef ISAPNP_REGION_OK
1094 		release_region(_PIDXR, 1);
1095 #endif
1096 		return -EBUSY;
1097 	}
1098 
1099 	if (pnp_register_protocol(&isapnp_protocol) < 0)
1100 		return -EBUSY;
1101 
1102 	/*
1103 	 *      Print a message. The existing ISAPnP code is hanging machines
1104 	 *      so let the user know where.
1105 	 */
1106 
1107 	printk(KERN_INFO "isapnp: Scanning for PnP cards...\n");
1108 	if (isapnp_rdp >= 0x203 && isapnp_rdp <= 0x3ff) {
1109 		isapnp_rdp |= 3;
1110 		if (!request_region(isapnp_rdp, 1, "isapnp read")) {
1111 			printk(KERN_ERR
1112 			       "isapnp: Read Data Register 0x%x already used\n",
1113 			       isapnp_rdp);
1114 #ifdef ISAPNP_REGION_OK
1115 			release_region(_PIDXR, 1);
1116 #endif
1117 			release_region(_PNPWRP, 1);
1118 			return -EBUSY;
1119 		}
1120 		isapnp_set_rdp();
1121 	}
1122 	if (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff) {
1123 		cards = isapnp_isolate();
1124 		if (cards < 0 || (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff)) {
1125 #ifdef ISAPNP_REGION_OK
1126 			release_region(_PIDXR, 1);
1127 #endif
1128 			release_region(_PNPWRP, 1);
1129 			printk(KERN_INFO
1130 			       "isapnp: No Plug & Play device found\n");
1131 			return 0;
1132 		}
1133 		request_region(isapnp_rdp, 1, "isapnp read");
1134 	}
1135 	isapnp_build_device_list();
1136 	cards = 0;
1137 
1138 	protocol_for_each_card(&isapnp_protocol, card) {
1139 		cards++;
1140 		if (isapnp_verbose) {
1141 			printk(KERN_INFO "isapnp: Card '%s'\n",
1142 			       card->name[0] ? card->name : "Unknown");
1143 			if (isapnp_verbose < 2)
1144 				continue;
1145 			card_for_each_dev(card, dev) {
1146 				printk(KERN_INFO "isapnp:   Device '%s'\n",
1147 				       dev->name[0] ? dev->name : "Unknown");
1148 			}
1149 		}
1150 	}
1151 	if (cards)
1152 		printk(KERN_INFO
1153 		       "isapnp: %i Plug & Play card%s detected total\n", cards,
1154 		       cards > 1 ? "s" : "");
1155 	else
1156 		printk(KERN_INFO "isapnp: No Plug & Play card found\n");
1157 
1158 	isapnp_proc_init();
1159 	return 0;
1160 }
1161 
1162 device_initcall(isapnp_init);
1163 
1164 /* format is: noisapnp */
1165 
1166 static int __init isapnp_setup_disable(char *str)
1167 {
1168 	isapnp_disable = 1;
1169 	return 1;
1170 }
1171 
1172 __setup("noisapnp", isapnp_setup_disable);
1173 
1174 /* format is: isapnp=rdp,reset,skip_pci_scan,verbose */
1175 
1176 static int __init isapnp_setup_isapnp(char *str)
1177 {
1178 	(void)((get_option(&str, &isapnp_rdp) == 2) &&
1179 	       (get_option(&str, &isapnp_reset) == 2) &&
1180 	       (get_option(&str, &isapnp_verbose) == 2));
1181 	return 1;
1182 }
1183 
1184 __setup("isapnp=", isapnp_setup_isapnp);
1185