xref: /linux/drivers/pnp/isapnp/core.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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/delay.h>
41 #include <linux/init.h>
42 #include <linux/isapnp.h>
43 #include <linux/mutex.h>
44 #include <asm/io.h>
45 
46 #include "../base.h"
47 
48 #if 0
49 #define ISAPNP_REGION_OK
50 #endif
51 
52 int isapnp_disable;		/* Disable ISA PnP */
53 static int isapnp_rdp;		/* Read Data Port */
54 static int isapnp_reset = 1;	/* reset all PnP cards (deactivate) */
55 static int isapnp_verbose = 1;	/* verbose mode */
56 
57 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
58 MODULE_DESCRIPTION("Generic ISA Plug & Play support");
59 module_param(isapnp_disable, int, 0);
60 MODULE_PARM_DESC(isapnp_disable, "ISA Plug & Play disable");
61 module_param(isapnp_rdp, int, 0);
62 MODULE_PARM_DESC(isapnp_rdp, "ISA Plug & Play read data port");
63 module_param(isapnp_reset, int, 0);
64 MODULE_PARM_DESC(isapnp_reset, "ISA Plug & Play reset all cards");
65 module_param(isapnp_verbose, int, 0);
66 MODULE_PARM_DESC(isapnp_verbose, "ISA Plug & Play verbose mode");
67 MODULE_LICENSE("GPL");
68 
69 #define _PIDXR		0x279
70 #define _PNPWRP		0xa79
71 
72 /* short tags */
73 #define _STAG_PNPVERNO		0x01
74 #define _STAG_LOGDEVID		0x02
75 #define _STAG_COMPATDEVID	0x03
76 #define _STAG_IRQ		0x04
77 #define _STAG_DMA		0x05
78 #define _STAG_STARTDEP		0x06
79 #define _STAG_ENDDEP		0x07
80 #define _STAG_IOPORT		0x08
81 #define _STAG_FIXEDIO		0x09
82 #define _STAG_VENDOR		0x0e
83 #define _STAG_END		0x0f
84 /* long tags */
85 #define _LTAG_MEMRANGE		0x81
86 #define _LTAG_ANSISTR		0x82
87 #define _LTAG_UNICODESTR	0x83
88 #define _LTAG_VENDOR		0x84
89 #define _LTAG_MEM32RANGE	0x85
90 #define _LTAG_FIXEDMEM32RANGE	0x86
91 
92 /* Logical device control and configuration registers */
93 
94 #define ISAPNP_CFG_ACTIVATE	0x30	/* byte */
95 #define ISAPNP_CFG_MEM		0x40	/* 4 * dword */
96 #define ISAPNP_CFG_PORT		0x60	/* 8 * word */
97 #define ISAPNP_CFG_IRQ		0x70	/* 2 * word */
98 #define ISAPNP_CFG_DMA		0x74	/* 2 * byte */
99 
100 /*
101  * Sizes of ISAPNP logical device configuration register sets.
102  * See PNP-ISA-v1.0a.pdf, Appendix A.
103  */
104 #define ISAPNP_MAX_MEM		4
105 #define ISAPNP_MAX_PORT		8
106 #define ISAPNP_MAX_IRQ		2
107 #define ISAPNP_MAX_DMA		2
108 
109 static unsigned char isapnp_checksum_value;
110 static DEFINE_MUTEX(isapnp_cfg_mutex);
111 static int isapnp_csn_count;
112 
113 /* some prototypes */
114 
115 static inline void write_data(unsigned char x)
116 {
117 	outb(x, _PNPWRP);
118 }
119 
120 static inline void write_address(unsigned char x)
121 {
122 	outb(x, _PIDXR);
123 	udelay(20);
124 }
125 
126 static inline unsigned char read_data(void)
127 {
128 	unsigned char val = inb(isapnp_rdp);
129 	return val;
130 }
131 
132 unsigned char isapnp_read_byte(unsigned char idx)
133 {
134 	write_address(idx);
135 	return read_data();
136 }
137 
138 static unsigned short isapnp_read_word(unsigned char idx)
139 {
140 	unsigned short val;
141 
142 	val = isapnp_read_byte(idx);
143 	val = (val << 8) + isapnp_read_byte(idx + 1);
144 	return val;
145 }
146 
147 void isapnp_write_byte(unsigned char idx, unsigned char val)
148 {
149 	write_address(idx);
150 	write_data(val);
151 }
152 
153 static void isapnp_write_word(unsigned char idx, unsigned short val)
154 {
155 	isapnp_write_byte(idx, val >> 8);
156 	isapnp_write_byte(idx + 1, val);
157 }
158 
159 static void isapnp_key(void)
160 {
161 	unsigned char code = 0x6a, msb;
162 	int i;
163 
164 	mdelay(1);
165 	write_address(0x00);
166 	write_address(0x00);
167 
168 	write_address(code);
169 
170 	for (i = 1; i < 32; i++) {
171 		msb = ((code & 0x01) ^ ((code & 0x02) >> 1)) << 7;
172 		code = (code >> 1) | msb;
173 		write_address(code);
174 	}
175 }
176 
177 /* place all pnp cards in wait-for-key state */
178 static void isapnp_wait(void)
179 {
180 	isapnp_write_byte(0x02, 0x02);
181 }
182 
183 static void isapnp_wake(unsigned char csn)
184 {
185 	isapnp_write_byte(0x03, csn);
186 }
187 
188 static void isapnp_device(unsigned char logdev)
189 {
190 	isapnp_write_byte(0x07, logdev);
191 }
192 
193 static void isapnp_activate(unsigned char logdev)
194 {
195 	isapnp_device(logdev);
196 	isapnp_write_byte(ISAPNP_CFG_ACTIVATE, 1);
197 	udelay(250);
198 }
199 
200 static void isapnp_deactivate(unsigned char logdev)
201 {
202 	isapnp_device(logdev);
203 	isapnp_write_byte(ISAPNP_CFG_ACTIVATE, 0);
204 	udelay(500);
205 }
206 
207 static void __init isapnp_peek(unsigned char *data, int bytes)
208 {
209 	int i, j;
210 	unsigned char d = 0;
211 
212 	for (i = 1; i <= bytes; i++) {
213 		for (j = 0; j < 20; j++) {
214 			d = isapnp_read_byte(0x05);
215 			if (d & 1)
216 				break;
217 			udelay(100);
218 		}
219 		if (!(d & 1)) {
220 			if (data != NULL)
221 				*data++ = 0xff;
222 			continue;
223 		}
224 		d = isapnp_read_byte(0x04);	/* PRESDI */
225 		isapnp_checksum_value += d;
226 		if (data != NULL)
227 			*data++ = d;
228 	}
229 }
230 
231 #define RDP_STEP	32	/* minimum is 4 */
232 
233 static int isapnp_next_rdp(void)
234 {
235 	int rdp = isapnp_rdp;
236 	static int old_rdp = 0;
237 
238 	if (old_rdp) {
239 		release_region(old_rdp, 1);
240 		old_rdp = 0;
241 	}
242 	while (rdp <= 0x3ff) {
243 		/*
244 		 *      We cannot use NE2000 probe spaces for ISAPnP or we
245 		 *      will lock up machines.
246 		 */
247 		if ((rdp < 0x280 || rdp > 0x380)
248 		    && request_region(rdp, 1, "ISAPnP")) {
249 			isapnp_rdp = rdp;
250 			old_rdp = rdp;
251 			return 0;
252 		}
253 		rdp += RDP_STEP;
254 	}
255 	return -1;
256 }
257 
258 /* Set read port address */
259 static inline void isapnp_set_rdp(void)
260 {
261 	isapnp_write_byte(0x00, isapnp_rdp >> 2);
262 	udelay(100);
263 }
264 
265 /*
266  *	Perform an isolation. The port selection code now tries to avoid
267  *	"dangerous to read" ports.
268  */
269 static int __init isapnp_isolate_rdp_select(void)
270 {
271 	isapnp_wait();
272 	isapnp_key();
273 
274 	/* Control: reset CSN and conditionally everything else too */
275 	isapnp_write_byte(0x02, isapnp_reset ? 0x05 : 0x04);
276 	mdelay(2);
277 
278 	isapnp_wait();
279 	isapnp_key();
280 	isapnp_wake(0x00);
281 
282 	if (isapnp_next_rdp() < 0) {
283 		isapnp_wait();
284 		return -1;
285 	}
286 
287 	isapnp_set_rdp();
288 	udelay(1000);
289 	write_address(0x01);
290 	udelay(1000);
291 	return 0;
292 }
293 
294 /*
295  *  Isolate (assign uniqued CSN) to all ISA PnP devices.
296  */
297 static int __init isapnp_isolate(void)
298 {
299 	unsigned char checksum = 0x6a;
300 	unsigned char chksum = 0x00;
301 	unsigned char bit = 0x00;
302 	int data;
303 	int csn = 0;
304 	int i;
305 	int iteration = 1;
306 
307 	isapnp_rdp = 0x213;
308 	if (isapnp_isolate_rdp_select() < 0)
309 		return -1;
310 
311 	while (1) {
312 		for (i = 1; i <= 64; i++) {
313 			data = read_data() << 8;
314 			udelay(250);
315 			data = data | read_data();
316 			udelay(250);
317 			if (data == 0x55aa)
318 				bit = 0x01;
319 			checksum =
320 			    ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7)
321 			    | (checksum >> 1);
322 			bit = 0x00;
323 		}
324 		for (i = 65; i <= 72; i++) {
325 			data = read_data() << 8;
326 			udelay(250);
327 			data = data | read_data();
328 			udelay(250);
329 			if (data == 0x55aa)
330 				chksum |= (1 << (i - 65));
331 		}
332 		if (checksum != 0x00 && checksum == chksum) {
333 			csn++;
334 
335 			isapnp_write_byte(0x06, csn);
336 			udelay(250);
337 			iteration++;
338 			isapnp_wake(0x00);
339 			isapnp_set_rdp();
340 			udelay(1000);
341 			write_address(0x01);
342 			udelay(1000);
343 			goto __next;
344 		}
345 		if (iteration == 1) {
346 			isapnp_rdp += RDP_STEP;
347 			if (isapnp_isolate_rdp_select() < 0)
348 				return -1;
349 		} else if (iteration > 1) {
350 			break;
351 		}
352 __next:
353 		if (csn == 255)
354 			break;
355 		checksum = 0x6a;
356 		chksum = 0x00;
357 		bit = 0x00;
358 	}
359 	isapnp_wait();
360 	isapnp_csn_count = csn;
361 	return csn;
362 }
363 
364 /*
365  *  Read one tag from stream.
366  */
367 static int __init isapnp_read_tag(unsigned char *type, unsigned short *size)
368 {
369 	unsigned char tag, tmp[2];
370 
371 	isapnp_peek(&tag, 1);
372 	if (tag == 0)		/* invalid tag */
373 		return -1;
374 	if (tag & 0x80) {	/* large item */
375 		*type = tag;
376 		isapnp_peek(tmp, 2);
377 		*size = (tmp[1] << 8) | tmp[0];
378 	} else {
379 		*type = (tag >> 3) & 0x0f;
380 		*size = tag & 0x07;
381 	}
382 	if (*type == 0xff && *size == 0xffff)	/* probably invalid data */
383 		return -1;
384 	return 0;
385 }
386 
387 /*
388  *  Skip specified number of bytes from stream.
389  */
390 static void __init isapnp_skip_bytes(int count)
391 {
392 	isapnp_peek(NULL, count);
393 }
394 
395 /*
396  *  Parse logical device tag.
397  */
398 static struct pnp_dev *__init isapnp_parse_device(struct pnp_card *card,
399 						  int size, int number)
400 {
401 	unsigned char tmp[6];
402 	struct pnp_dev *dev;
403 	u32 eisa_id;
404 	char id[8];
405 
406 	isapnp_peek(tmp, size);
407 	eisa_id = tmp[0] | tmp[1] << 8 | tmp[2] << 16 | tmp[3] << 24;
408 	pnp_eisa_id_to_string(eisa_id, id);
409 
410 	dev = pnp_alloc_dev(&isapnp_protocol, number, id);
411 	if (!dev)
412 		return NULL;
413 
414 	dev->card = card;
415 	dev->capabilities |= PNP_CONFIGURABLE;
416 	dev->capabilities |= PNP_READ;
417 	dev->capabilities |= PNP_WRITE;
418 	dev->capabilities |= PNP_DISABLE;
419 	pnp_init_resources(dev);
420 	return dev;
421 }
422 
423 /*
424  *  Add IRQ resource to resources list.
425  */
426 static void __init isapnp_parse_irq_resource(struct pnp_dev *dev,
427 					     unsigned int option_flags,
428 					     int size)
429 {
430 	unsigned char tmp[3];
431 	unsigned long bits;
432 	pnp_irq_mask_t map;
433 	unsigned char flags = IORESOURCE_IRQ_HIGHEDGE;
434 
435 	isapnp_peek(tmp, size);
436 	bits = (tmp[1] << 8) | tmp[0];
437 
438 	bitmap_zero(map.bits, PNP_IRQ_NR);
439 	bitmap_copy(map.bits, &bits, 16);
440 
441 	if (size > 2)
442 		flags = tmp[2];
443 
444 	pnp_register_irq_resource(dev, option_flags, &map, flags);
445 }
446 
447 /*
448  *  Add DMA resource to resources list.
449  */
450 static void __init isapnp_parse_dma_resource(struct pnp_dev *dev,
451 					     unsigned int option_flags,
452 					     int size)
453 {
454 	unsigned char tmp[2];
455 
456 	isapnp_peek(tmp, size);
457 	pnp_register_dma_resource(dev, option_flags, tmp[0], tmp[1]);
458 }
459 
460 /*
461  *  Add port resource to resources list.
462  */
463 static void __init isapnp_parse_port_resource(struct pnp_dev *dev,
464 					      unsigned int option_flags,
465 					      int size)
466 {
467 	unsigned char tmp[7];
468 	resource_size_t min, max, align, len;
469 	unsigned char flags;
470 
471 	isapnp_peek(tmp, size);
472 	min = (tmp[2] << 8) | tmp[1];
473 	max = (tmp[4] << 8) | tmp[3];
474 	align = tmp[5];
475 	len = tmp[6];
476 	flags = tmp[0] ? IORESOURCE_IO_16BIT_ADDR : 0;
477 	pnp_register_port_resource(dev, option_flags,
478 				   min, max, align, len, flags);
479 }
480 
481 /*
482  *  Add fixed port resource to resources list.
483  */
484 static void __init isapnp_parse_fixed_port_resource(struct pnp_dev *dev,
485 						    unsigned int option_flags,
486 						    int size)
487 {
488 	unsigned char tmp[3];
489 	resource_size_t base, len;
490 
491 	isapnp_peek(tmp, size);
492 	base = (tmp[1] << 8) | tmp[0];
493 	len = tmp[2];
494 	pnp_register_port_resource(dev, option_flags, base, base, 0, len,
495 				   IORESOURCE_IO_FIXED);
496 }
497 
498 /*
499  *  Add memory resource to resources list.
500  */
501 static void __init isapnp_parse_mem_resource(struct pnp_dev *dev,
502 					     unsigned int option_flags,
503 					     int size)
504 {
505 	unsigned char tmp[9];
506 	resource_size_t min, max, align, len;
507 	unsigned char flags;
508 
509 	isapnp_peek(tmp, size);
510 	min = ((tmp[2] << 8) | tmp[1]) << 8;
511 	max = ((tmp[4] << 8) | tmp[3]) << 8;
512 	align = (tmp[6] << 8) | tmp[5];
513 	len = ((tmp[8] << 8) | tmp[7]) << 8;
514 	flags = tmp[0];
515 	pnp_register_mem_resource(dev, option_flags,
516 				  min, max, align, len, flags);
517 }
518 
519 /*
520  *  Add 32-bit memory resource to resources list.
521  */
522 static void __init isapnp_parse_mem32_resource(struct pnp_dev *dev,
523 					       unsigned int option_flags,
524 					       int size)
525 {
526 	unsigned char tmp[17];
527 	resource_size_t min, max, align, len;
528 	unsigned char flags;
529 
530 	isapnp_peek(tmp, size);
531 	min = (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
532 	max = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5];
533 	align = (tmp[12] << 24) | (tmp[11] << 16) | (tmp[10] << 8) | tmp[9];
534 	len = (tmp[16] << 24) | (tmp[15] << 16) | (tmp[14] << 8) | tmp[13];
535 	flags = tmp[0];
536 	pnp_register_mem_resource(dev, option_flags,
537 				  min, max, align, len, flags);
538 }
539 
540 /*
541  *  Add 32-bit fixed memory resource to resources list.
542  */
543 static void __init isapnp_parse_fixed_mem32_resource(struct pnp_dev *dev,
544 						     unsigned int option_flags,
545 						     int size)
546 {
547 	unsigned char tmp[9];
548 	resource_size_t base, len;
549 	unsigned char flags;
550 
551 	isapnp_peek(tmp, size);
552 	base = (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
553 	len = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5];
554 	flags = tmp[0];
555 	pnp_register_mem_resource(dev, option_flags, base, base, 0, len, flags);
556 }
557 
558 /*
559  *  Parse card name for ISA PnP device.
560  */
561 static void __init
562 isapnp_parse_name(char *name, unsigned int name_max, unsigned short *size)
563 {
564 	if (name[0] == '\0') {
565 		unsigned short size1 =
566 		    *size >= name_max ? (name_max - 1) : *size;
567 		isapnp_peek(name, size1);
568 		name[size1] = '\0';
569 		*size -= size1;
570 
571 		/* clean whitespace from end of string */
572 		while (size1 > 0 && name[--size1] == ' ')
573 			name[size1] = '\0';
574 	}
575 }
576 
577 /*
578  *  Parse resource map for logical device.
579  */
580 static int __init isapnp_create_device(struct pnp_card *card,
581 				       unsigned short size)
582 {
583 	int number = 0, skip = 0, priority, compat = 0;
584 	unsigned char type, tmp[17];
585 	unsigned int option_flags;
586 	struct pnp_dev *dev;
587 	u32 eisa_id;
588 	char id[8];
589 
590 	if ((dev = isapnp_parse_device(card, size, number++)) == NULL)
591 		return 1;
592 	option_flags = 0;
593 	pnp_add_card_device(card, dev);
594 
595 	while (1) {
596 		if (isapnp_read_tag(&type, &size) < 0)
597 			return 1;
598 		if (skip && type != _STAG_LOGDEVID && type != _STAG_END)
599 			goto __skip;
600 		switch (type) {
601 		case _STAG_LOGDEVID:
602 			if (size >= 5 && size <= 6) {
603 				if ((dev =
604 				     isapnp_parse_device(card, size,
605 							 number++)) == NULL)
606 					return 1;
607 				size = 0;
608 				skip = 0;
609 				option_flags = 0;
610 				pnp_add_card_device(card, dev);
611 			} else {
612 				skip = 1;
613 			}
614 			compat = 0;
615 			break;
616 		case _STAG_COMPATDEVID:
617 			if (size == 4 && compat < DEVICE_COUNT_COMPATIBLE) {
618 				isapnp_peek(tmp, 4);
619 				eisa_id = tmp[0] | tmp[1] << 8 |
620 					  tmp[2] << 16 | tmp[3] << 24;
621 				pnp_eisa_id_to_string(eisa_id, id);
622 				pnp_add_id(dev, id);
623 				compat++;
624 				size = 0;
625 			}
626 			break;
627 		case _STAG_IRQ:
628 			if (size < 2 || size > 3)
629 				goto __skip;
630 			isapnp_parse_irq_resource(dev, option_flags, size);
631 			size = 0;
632 			break;
633 		case _STAG_DMA:
634 			if (size != 2)
635 				goto __skip;
636 			isapnp_parse_dma_resource(dev, option_flags, size);
637 			size = 0;
638 			break;
639 		case _STAG_STARTDEP:
640 			if (size > 1)
641 				goto __skip;
642 			priority = PNP_RES_PRIORITY_ACCEPTABLE;
643 			if (size > 0) {
644 				isapnp_peek(tmp, size);
645 				priority = tmp[0];
646 				size = 0;
647 			}
648 			option_flags = pnp_new_dependent_set(dev, priority);
649 			break;
650 		case _STAG_ENDDEP:
651 			if (size != 0)
652 				goto __skip;
653 			option_flags = 0;
654 			break;
655 		case _STAG_IOPORT:
656 			if (size != 7)
657 				goto __skip;
658 			isapnp_parse_port_resource(dev, option_flags, size);
659 			size = 0;
660 			break;
661 		case _STAG_FIXEDIO:
662 			if (size != 3)
663 				goto __skip;
664 			isapnp_parse_fixed_port_resource(dev, option_flags,
665 							 size);
666 			size = 0;
667 			break;
668 		case _STAG_VENDOR:
669 			break;
670 		case _LTAG_MEMRANGE:
671 			if (size != 9)
672 				goto __skip;
673 			isapnp_parse_mem_resource(dev, option_flags, size);
674 			size = 0;
675 			break;
676 		case _LTAG_ANSISTR:
677 			isapnp_parse_name(dev->name, sizeof(dev->name), &size);
678 			break;
679 		case _LTAG_UNICODESTR:
680 			/* silently ignore */
681 			/* who use unicode for hardware identification? */
682 			break;
683 		case _LTAG_VENDOR:
684 			break;
685 		case _LTAG_MEM32RANGE:
686 			if (size != 17)
687 				goto __skip;
688 			isapnp_parse_mem32_resource(dev, option_flags, size);
689 			size = 0;
690 			break;
691 		case _LTAG_FIXEDMEM32RANGE:
692 			if (size != 9)
693 				goto __skip;
694 			isapnp_parse_fixed_mem32_resource(dev, option_flags,
695 							  size);
696 			size = 0;
697 			break;
698 		case _STAG_END:
699 			if (size > 0)
700 				isapnp_skip_bytes(size);
701 			return 1;
702 		default:
703 			dev_err(&dev->dev, "unknown tag %#x (card %i), "
704 				"ignored\n", type, card->number);
705 		}
706 __skip:
707 		if (size > 0)
708 			isapnp_skip_bytes(size);
709 	}
710 	return 0;
711 }
712 
713 /*
714  *  Parse resource map for ISA PnP card.
715  */
716 static void __init isapnp_parse_resource_map(struct pnp_card *card)
717 {
718 	unsigned char type, tmp[17];
719 	unsigned short size;
720 
721 	while (1) {
722 		if (isapnp_read_tag(&type, &size) < 0)
723 			return;
724 		switch (type) {
725 		case _STAG_PNPVERNO:
726 			if (size != 2)
727 				goto __skip;
728 			isapnp_peek(tmp, 2);
729 			card->pnpver = tmp[0];
730 			card->productver = tmp[1];
731 			size = 0;
732 			break;
733 		case _STAG_LOGDEVID:
734 			if (size >= 5 && size <= 6) {
735 				if (isapnp_create_device(card, size) == 1)
736 					return;
737 				size = 0;
738 			}
739 			break;
740 		case _STAG_VENDOR:
741 			break;
742 		case _LTAG_ANSISTR:
743 			isapnp_parse_name(card->name, sizeof(card->name),
744 					  &size);
745 			break;
746 		case _LTAG_UNICODESTR:
747 			/* silently ignore */
748 			/* who use unicode for hardware identification? */
749 			break;
750 		case _LTAG_VENDOR:
751 			break;
752 		case _STAG_END:
753 			if (size > 0)
754 				isapnp_skip_bytes(size);
755 			return;
756 		default:
757 			dev_err(&card->dev, "unknown tag %#x, ignored\n",
758 			       type);
759 		}
760 __skip:
761 		if (size > 0)
762 			isapnp_skip_bytes(size);
763 	}
764 }
765 
766 /*
767  *  Compute ISA PnP checksum for first eight bytes.
768  */
769 static unsigned char __init isapnp_checksum(unsigned char *data)
770 {
771 	int i, j;
772 	unsigned char checksum = 0x6a, bit, b;
773 
774 	for (i = 0; i < 8; i++) {
775 		b = data[i];
776 		for (j = 0; j < 8; j++) {
777 			bit = 0;
778 			if (b & (1 << j))
779 				bit = 1;
780 			checksum =
781 			    ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7)
782 			    | (checksum >> 1);
783 		}
784 	}
785 	return checksum;
786 }
787 
788 /*
789  *  Build device list for all present ISA PnP devices.
790  */
791 static int __init isapnp_build_device_list(void)
792 {
793 	int csn;
794 	unsigned char header[9], checksum;
795 	struct pnp_card *card;
796 	u32 eisa_id;
797 	char id[8];
798 
799 	isapnp_wait();
800 	isapnp_key();
801 	for (csn = 1; csn <= isapnp_csn_count; csn++) {
802 		isapnp_wake(csn);
803 		isapnp_peek(header, 9);
804 		checksum = isapnp_checksum(header);
805 		eisa_id = header[0] | header[1] << 8 |
806 			  header[2] << 16 | header[3] << 24;
807 		pnp_eisa_id_to_string(eisa_id, id);
808 		card = pnp_alloc_card(&isapnp_protocol, csn, id);
809 		if (!card)
810 			continue;
811 
812 		INIT_LIST_HEAD(&card->devices);
813 		card->serial =
814 		    (header[7] << 24) | (header[6] << 16) | (header[5] << 8) |
815 		    header[4];
816 		isapnp_checksum_value = 0x00;
817 		isapnp_parse_resource_map(card);
818 		if (isapnp_checksum_value != 0x00)
819 			dev_err(&card->dev, "invalid checksum %#x\n",
820 				isapnp_checksum_value);
821 		card->checksum = isapnp_checksum_value;
822 
823 		pnp_add_card(card);
824 	}
825 	isapnp_wait();
826 	return 0;
827 }
828 
829 /*
830  *  Basic configuration routines.
831  */
832 
833 int isapnp_present(void)
834 {
835 	struct pnp_card *card;
836 
837 	pnp_for_each_card(card) {
838 		if (card->protocol == &isapnp_protocol)
839 			return 1;
840 	}
841 	return 0;
842 }
843 
844 int isapnp_cfg_begin(int csn, int logdev)
845 {
846 	if (csn < 1 || csn > isapnp_csn_count || logdev > 10)
847 		return -EINVAL;
848 	mutex_lock(&isapnp_cfg_mutex);
849 	isapnp_wait();
850 	isapnp_key();
851 	isapnp_wake(csn);
852 #if 0
853 	/* to avoid malfunction when the isapnptools package is used */
854 	/* we must set RDP to our value again */
855 	/* it is possible to set RDP only in the isolation phase */
856 	/*   Jens Thoms Toerring <Jens.Toerring@physik.fu-berlin.de> */
857 	isapnp_write_byte(0x02, 0x04);	/* clear CSN of card */
858 	mdelay(2);		/* is this necessary? */
859 	isapnp_wake(csn);	/* bring card into sleep state */
860 	isapnp_wake(0);		/* bring card into isolation state */
861 	isapnp_set_rdp();	/* reset the RDP port */
862 	udelay(1000);		/* delay 1000us */
863 	isapnp_write_byte(0x06, csn);	/* reset CSN to previous value */
864 	udelay(250);		/* is this necessary? */
865 #endif
866 	if (logdev >= 0)
867 		isapnp_device(logdev);
868 	return 0;
869 }
870 
871 int isapnp_cfg_end(void)
872 {
873 	isapnp_wait();
874 	mutex_unlock(&isapnp_cfg_mutex);
875 	return 0;
876 }
877 
878 /*
879  *  Initialization.
880  */
881 
882 EXPORT_SYMBOL(isapnp_protocol);
883 EXPORT_SYMBOL(isapnp_present);
884 EXPORT_SYMBOL(isapnp_cfg_begin);
885 EXPORT_SYMBOL(isapnp_cfg_end);
886 EXPORT_SYMBOL(isapnp_write_byte);
887 
888 static int isapnp_get_resources(struct pnp_dev *dev)
889 {
890 	int i, ret;
891 
892 	pnp_dbg(&dev->dev, "get resources\n");
893 	pnp_init_resources(dev);
894 	isapnp_cfg_begin(dev->card->number, dev->number);
895 	dev->active = isapnp_read_byte(ISAPNP_CFG_ACTIVATE);
896 	if (!dev->active)
897 		goto __end;
898 
899 	for (i = 0; i < ISAPNP_MAX_PORT; i++) {
900 		ret = isapnp_read_word(ISAPNP_CFG_PORT + (i << 1));
901 		pnp_add_io_resource(dev, ret, ret,
902 				    ret == 0 ? IORESOURCE_DISABLED : 0);
903 	}
904 	for (i = 0; i < ISAPNP_MAX_MEM; i++) {
905 		ret = isapnp_read_word(ISAPNP_CFG_MEM + (i << 3)) << 8;
906 		pnp_add_mem_resource(dev, ret, ret,
907 				     ret == 0 ? IORESOURCE_DISABLED : 0);
908 	}
909 	for (i = 0; i < ISAPNP_MAX_IRQ; i++) {
910 		ret = isapnp_read_word(ISAPNP_CFG_IRQ + (i << 1)) >> 8;
911 		pnp_add_irq_resource(dev, ret,
912 				     ret == 0 ? IORESOURCE_DISABLED : 0);
913 	}
914 	for (i = 0; i < ISAPNP_MAX_DMA; i++) {
915 		ret = isapnp_read_byte(ISAPNP_CFG_DMA + i);
916 		pnp_add_dma_resource(dev, ret,
917 				     ret == 4 ? IORESOURCE_DISABLED : 0);
918 	}
919 
920 __end:
921 	isapnp_cfg_end();
922 	return 0;
923 }
924 
925 static int isapnp_set_resources(struct pnp_dev *dev)
926 {
927 	struct resource *res;
928 	int tmp;
929 
930 	pnp_dbg(&dev->dev, "set resources\n");
931 	isapnp_cfg_begin(dev->card->number, dev->number);
932 	dev->active = 1;
933 	for (tmp = 0; tmp < ISAPNP_MAX_PORT; tmp++) {
934 		res = pnp_get_resource(dev, IORESOURCE_IO, tmp);
935 		if (pnp_resource_enabled(res)) {
936 			pnp_dbg(&dev->dev, "  set io  %d to %#llx\n",
937 				tmp, (unsigned long long) res->start);
938 			isapnp_write_word(ISAPNP_CFG_PORT + (tmp << 1),
939 					  res->start);
940 		}
941 	}
942 	for (tmp = 0; tmp < ISAPNP_MAX_IRQ; tmp++) {
943 		res = pnp_get_resource(dev, IORESOURCE_IRQ, tmp);
944 		if (pnp_resource_enabled(res)) {
945 			int irq = res->start;
946 			if (irq == 2)
947 				irq = 9;
948 			pnp_dbg(&dev->dev, "  set irq %d to %d\n", tmp, irq);
949 			isapnp_write_byte(ISAPNP_CFG_IRQ + (tmp << 1), irq);
950 		}
951 	}
952 	for (tmp = 0; tmp < ISAPNP_MAX_DMA; tmp++) {
953 		res = pnp_get_resource(dev, IORESOURCE_DMA, tmp);
954 		if (pnp_resource_enabled(res)) {
955 			pnp_dbg(&dev->dev, "  set dma %d to %lld\n",
956 				tmp, (unsigned long long) res->start);
957 			isapnp_write_byte(ISAPNP_CFG_DMA + tmp, res->start);
958 		}
959 	}
960 	for (tmp = 0; tmp < ISAPNP_MAX_MEM; tmp++) {
961 		res = pnp_get_resource(dev, IORESOURCE_MEM, tmp);
962 		if (pnp_resource_enabled(res)) {
963 			pnp_dbg(&dev->dev, "  set mem %d to %#llx\n",
964 				tmp, (unsigned long long) res->start);
965 			isapnp_write_word(ISAPNP_CFG_MEM + (tmp << 3),
966 					  (res->start >> 8) & 0xffff);
967 		}
968 	}
969 	/* FIXME: We aren't handling 32bit mems properly here */
970 	isapnp_activate(dev->number);
971 	isapnp_cfg_end();
972 	return 0;
973 }
974 
975 static int isapnp_disable_resources(struct pnp_dev *dev)
976 {
977 	if (!dev->active)
978 		return -EINVAL;
979 	isapnp_cfg_begin(dev->card->number, dev->number);
980 	isapnp_deactivate(dev->number);
981 	dev->active = 0;
982 	isapnp_cfg_end();
983 	return 0;
984 }
985 
986 struct pnp_protocol isapnp_protocol = {
987 	.name = "ISA Plug and Play",
988 	.get = isapnp_get_resources,
989 	.set = isapnp_set_resources,
990 	.disable = isapnp_disable_resources,
991 };
992 
993 static int __init isapnp_init(void)
994 {
995 	int cards;
996 	struct pnp_card *card;
997 	struct pnp_dev *dev;
998 
999 	if (isapnp_disable) {
1000 		printk(KERN_INFO "isapnp: ISA Plug & Play support disabled\n");
1001 		return 0;
1002 	}
1003 #ifdef CONFIG_PPC
1004 	if (check_legacy_ioport(_PIDXR) || check_legacy_ioport(_PNPWRP))
1005 		return -EINVAL;
1006 #endif
1007 #ifdef ISAPNP_REGION_OK
1008 	if (!request_region(_PIDXR, 1, "isapnp index")) {
1009 		printk(KERN_ERR "isapnp: Index Register 0x%x already used\n",
1010 		       _PIDXR);
1011 		return -EBUSY;
1012 	}
1013 #endif
1014 	if (!request_region(_PNPWRP, 1, "isapnp write")) {
1015 		printk(KERN_ERR
1016 		       "isapnp: Write Data Register 0x%x already used\n",
1017 		       _PNPWRP);
1018 #ifdef ISAPNP_REGION_OK
1019 		release_region(_PIDXR, 1);
1020 #endif
1021 		return -EBUSY;
1022 	}
1023 
1024 	if (pnp_register_protocol(&isapnp_protocol) < 0)
1025 		return -EBUSY;
1026 
1027 	/*
1028 	 *      Print a message. The existing ISAPnP code is hanging machines
1029 	 *      so let the user know where.
1030 	 */
1031 
1032 	printk(KERN_INFO "isapnp: Scanning for PnP cards...\n");
1033 	if (isapnp_rdp >= 0x203 && isapnp_rdp <= 0x3ff) {
1034 		isapnp_rdp |= 3;
1035 		if (!request_region(isapnp_rdp, 1, "isapnp read")) {
1036 			printk(KERN_ERR
1037 			       "isapnp: Read Data Register 0x%x already used\n",
1038 			       isapnp_rdp);
1039 #ifdef ISAPNP_REGION_OK
1040 			release_region(_PIDXR, 1);
1041 #endif
1042 			release_region(_PNPWRP, 1);
1043 			return -EBUSY;
1044 		}
1045 		isapnp_set_rdp();
1046 	}
1047 	if (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff) {
1048 		cards = isapnp_isolate();
1049 		if (cards < 0 || (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff)) {
1050 #ifdef ISAPNP_REGION_OK
1051 			release_region(_PIDXR, 1);
1052 #endif
1053 			release_region(_PNPWRP, 1);
1054 			printk(KERN_INFO
1055 			       "isapnp: No Plug & Play device found\n");
1056 			return 0;
1057 		}
1058 		request_region(isapnp_rdp, 1, "isapnp read");
1059 	}
1060 	isapnp_build_device_list();
1061 	cards = 0;
1062 
1063 	protocol_for_each_card(&isapnp_protocol, card) {
1064 		cards++;
1065 		if (isapnp_verbose) {
1066 			dev_info(&card->dev, "card '%s'\n",
1067 			       card->name[0] ? card->name : "unknown");
1068 			if (isapnp_verbose < 2)
1069 				continue;
1070 			card_for_each_dev(card, dev) {
1071 				dev_info(&card->dev, "device '%s'\n",
1072 				       dev->name[0] ? dev->name : "unknown");
1073 			}
1074 		}
1075 	}
1076 	if (cards)
1077 		printk(KERN_INFO
1078 		       "isapnp: %i Plug & Play card%s detected total\n", cards,
1079 		       cards > 1 ? "s" : "");
1080 	else
1081 		printk(KERN_INFO "isapnp: No Plug & Play card found\n");
1082 
1083 	isapnp_proc_init();
1084 	return 0;
1085 }
1086 
1087 device_initcall(isapnp_init);
1088 
1089 /* format is: noisapnp */
1090 
1091 static int __init isapnp_setup_disable(char *str)
1092 {
1093 	isapnp_disable = 1;
1094 	return 1;
1095 }
1096 
1097 __setup("noisapnp", isapnp_setup_disable);
1098 
1099 /* format is: isapnp=rdp,reset,skip_pci_scan,verbose */
1100 
1101 static int __init isapnp_setup_isapnp(char *str)
1102 {
1103 	(void)((get_option(&str, &isapnp_rdp) == 2) &&
1104 	       (get_option(&str, &isapnp_reset) == 2) &&
1105 	       (get_option(&str, &isapnp_verbose) == 2));
1106 	return 1;
1107 }
1108 
1109 __setup("isapnp=", isapnp_setup_isapnp);
1110