core.c revision a2822e7f00cdccbff8e507b5ebbddce1aa95eb5d
1/*
2 * pnpbios -- PnP BIOS driver
3 *
4 * This driver provides access to Plug-'n'-Play services provided by
5 * the PnP BIOS firmware, described in the following documents:
6 *   Plug and Play BIOS Specification, Version 1.0A, 5 May 1994
7 *   Plug and Play BIOS Clarification Paper, 6 October 1994
8 *     Compaq Computer Corporation, Phoenix Technologies Ltd., Intel Corp.
9 *
10 * Originally (C) 1998 Christian Schmidt <schmidt@digadd.de>
11 * Modifications (C) 1998 Tom Lees <tom@lpsg.demon.co.uk>
12 * Minor reorganizations by David Hinds <dahinds@users.sourceforge.net>
13 * Further modifications (C) 2001, 2002 by:
14 *   Alan Cox <alan@redhat.com>
15 *   Thomas Hood
16 *   Brian Gerst <bgerst@didntduck.org>
17 *
18 * Ported to the PnP Layer and several additional improvements (C) 2002
19 * by Adam Belay <ambx1@neo.rr.com>
20 *
21 * This program is free software; you can redistribute it and/or modify it
22 * under the terms of the GNU General Public License as published by the
23 * Free Software Foundation; either version 2, or (at your option) any
24 * later version.
25 *
26 * This program is distributed in the hope that it will be useful, but
27 * WITHOUT ANY WARRANTY; without even the implied warranty of
28 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
29 * General Public License for more details.
30 *
31 * You should have received a copy of the GNU General Public License
32 * along with this program; if not, write to the Free Software
33 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
34 */
35
36/* Change Log
37 *
38 * Adam Belay - <ambx1@neo.rr.com> - March 16, 2003
39 * rev 1.01	Only call pnp_bios_dev_node_info once
40 *		Added pnpbios_print_status
41 *		Added several new error messages and info messages
42 *		Added pnpbios_interface_attach_device
43 *		integrated core and proc init system
44 *		Introduced PNPMODE flags
45 *		Removed some useless includes
46 */
47
48#include <linux/types.h>
49#include <linux/module.h>
50#include <linux/init.h>
51#include <linux/linkage.h>
52#include <linux/kernel.h>
53#include <linux/pnpbios.h>
54#include <linux/device.h>
55#include <linux/pnp.h>
56#include <linux/mm.h>
57#include <linux/smp.h>
58#include <linux/slab.h>
59#include <linux/kobject_uevent.h>
60#include <linux/completion.h>
61#include <linux/spinlock.h>
62#include <linux/dmi.h>
63#include <linux/delay.h>
64#include <linux/acpi.h>
65
66#include <asm/page.h>
67#include <asm/desc.h>
68#include <asm/system.h>
69#include <asm/byteorder.h>
70
71#include "pnpbios.h"
72
73
74/*
75 *
76 * PnP BIOS INTERFACE
77 *
78 */
79
80static union pnp_bios_install_struct * pnp_bios_install = NULL;
81
82int pnp_bios_present(void)
83{
84	return (pnp_bios_install != NULL);
85}
86
87struct pnp_dev_node_info node_info;
88
89/*
90 *
91 * DOCKING FUNCTIONS
92 *
93 */
94
95#ifdef CONFIG_HOTPLUG
96
97static int unloading = 0;
98static struct completion unload_sem;
99
100/*
101 * (Much of this belongs in a shared routine somewhere)
102 */
103
104static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
105{
106	char *argv [3], **envp, *buf, *scratch;
107	int i = 0, value;
108
109	if (!hotplug_path [0])
110		return -ENOENT;
111	if (!current->fs->root) {
112		return -EAGAIN;
113	}
114	if (!(envp = (char **) kcalloc (20, sizeof (char *), GFP_KERNEL))) {
115		return -ENOMEM;
116	}
117	if (!(buf = kcalloc (1, 256, GFP_KERNEL))) {
118		kfree (envp);
119		return -ENOMEM;
120	}
121
122	/* only one standardized param to hotplug command: type */
123	argv [0] = hotplug_path;
124	argv [1] = "dock";
125	argv [2] = NULL;
126
127	/* minimal command environment */
128	envp [i++] = "HOME=/";
129	envp [i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
130
131#ifdef	DEBUG
132	/* hint that policy agent should enter no-stdout debug mode */
133	envp [i++] = "DEBUG=kernel";
134#endif
135	/* extensible set of named bus-specific parameters,
136	 * supporting multiple driver selection algorithms.
137	 */
138	scratch = buf;
139
140	/* action:  add, remove */
141	envp [i++] = scratch;
142	scratch += sprintf (scratch, "ACTION=%s", dock?"add":"remove") + 1;
143
144	/* Report the ident for the dock */
145	envp [i++] = scratch;
146	scratch += sprintf (scratch, "DOCK=%x/%x/%x",
147		info->location_id, info->serial, info->capabilities);
148	envp[i] = NULL;
149
150	value = call_usermodehelper (argv [0], argv, envp, 0);
151	kfree (buf);
152	kfree (envp);
153	return 0;
154}
155
156/*
157 * Poll the PnP docking at regular intervals
158 */
159static int pnp_dock_thread(void * unused)
160{
161	static struct pnp_docking_station_info now;
162	int docked = -1, d = 0;
163	daemonize("kpnpbiosd");
164	allow_signal(SIGKILL);
165	while(!unloading && !signal_pending(current))
166	{
167		int status;
168
169		/*
170		 * Poll every 2 seconds
171		 */
172		msleep_interruptible(2000);
173
174		if(signal_pending(current)) {
175			if (try_to_freeze())
176				continue;
177			break;
178		}
179
180		status = pnp_bios_dock_station_info(&now);
181
182		switch(status)
183		{
184			/*
185			 * No dock to manage
186			 */
187			case PNP_FUNCTION_NOT_SUPPORTED:
188				complete_and_exit(&unload_sem, 0);
189			case PNP_SYSTEM_NOT_DOCKED:
190				d = 0;
191				break;
192			case PNP_SUCCESS:
193				d = 1;
194				break;
195			default:
196				pnpbios_print_status( "pnp_dock_thread", status );
197				continue;
198		}
199		if(d != docked)
200		{
201			if(pnp_dock_event(d, &now)==0)
202			{
203				docked = d;
204#if 0
205				printk(KERN_INFO "PnPBIOS: Docking station %stached\n", docked?"at":"de");
206#endif
207			}
208		}
209	}
210	complete_and_exit(&unload_sem, 0);
211}
212
213#endif   /* CONFIG_HOTPLUG */
214
215static int pnpbios_get_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
216{
217	u8 nodenum = dev->number;
218	struct pnp_bios_node * node;
219
220	/* just in case */
221	if(!pnpbios_is_dynamic(dev))
222		return -EPERM;
223
224	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
225	if (!node)
226		return -1;
227	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
228		kfree(node);
229		return -ENODEV;
230	}
231	pnpbios_read_resources_from_node(res, node);
232	dev->active = pnp_is_active(dev);
233	kfree(node);
234	return 0;
235}
236
237static int pnpbios_set_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
238{
239	u8 nodenum = dev->number;
240	struct pnp_bios_node * node;
241	int ret;
242
243	/* just in case */
244	if (!pnpbios_is_dynamic(dev))
245		return -EPERM;
246
247	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
248	if (!node)
249		return -1;
250	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
251		kfree(node);
252		return -ENODEV;
253	}
254	if(pnpbios_write_resources_to_node(res, node)<0) {
255		kfree(node);
256		return -1;
257	}
258	ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
259	kfree(node);
260	if (ret > 0)
261		ret = -1;
262	return ret;
263}
264
265static void pnpbios_zero_data_stream(struct pnp_bios_node * node)
266{
267	unsigned char * p = (char *)node->data;
268	unsigned char * end = (char *)(node->data + node->size);
269	unsigned int len;
270	int i;
271	while ((char *)p < (char *)end) {
272		if(p[0] & 0x80) { /* large tag */
273			len = (p[2] << 8) | p[1];
274			p += 3;
275		} else {
276			if (((p[0]>>3) & 0x0f) == 0x0f)
277				return;
278			len = p[0] & 0x07;
279			p += 1;
280		}
281		for (i = 0; i < len; i++)
282			p[i] = 0;
283		p += len;
284	}
285	printk(KERN_ERR "PnPBIOS: Resource structure did not contain an end tag.\n");
286}
287
288static int pnpbios_disable_resources(struct pnp_dev *dev)
289{
290	struct pnp_bios_node * node;
291	u8 nodenum = dev->number;
292	int ret;
293
294	/* just in case */
295	if(dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
296		return -EPERM;
297
298	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
299	if (!node)
300		return -ENOMEM;
301
302	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
303		kfree(node);
304		return -ENODEV;
305	}
306	pnpbios_zero_data_stream(node);
307
308	ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
309	kfree(node);
310	if (ret > 0)
311		ret = -1;
312	return ret;
313}
314
315/* PnP Layer support */
316
317struct pnp_protocol pnpbios_protocol = {
318	.name	= "Plug and Play BIOS",
319	.get	= pnpbios_get_resources,
320	.set	= pnpbios_set_resources,
321	.disable = pnpbios_disable_resources,
322};
323
324static int insert_device(struct pnp_dev *dev, struct pnp_bios_node * node)
325{
326	struct list_head * pos;
327	struct pnp_dev * pnp_dev;
328	struct pnp_id *dev_id;
329	char id[8];
330
331	/* check if the device is already added */
332	dev->number = node->handle;
333	list_for_each (pos, &pnpbios_protocol.devices){
334		pnp_dev = list_entry(pos, struct pnp_dev, protocol_list);
335		if (dev->number == pnp_dev->number)
336			return -1;
337	}
338
339	/* set the initial values for the PnP device */
340	dev_id = kcalloc(1, sizeof(struct pnp_id), GFP_KERNEL);
341	if (!dev_id)
342		return -1;
343	pnpid32_to_pnpid(node->eisa_id,id);
344	memcpy(dev_id->id,id,7);
345	pnp_add_id(dev_id, dev);
346	pnpbios_parse_data_stream(dev, node);
347	dev->active = pnp_is_active(dev);
348	dev->flags = node->flags;
349	if (!(dev->flags & PNPBIOS_NO_CONFIG))
350		dev->capabilities |= PNP_CONFIGURABLE;
351	if (!(dev->flags & PNPBIOS_NO_DISABLE))
352		dev->capabilities |= PNP_DISABLE;
353	dev->capabilities |= PNP_READ;
354	if (pnpbios_is_dynamic(dev))
355		dev->capabilities |= PNP_WRITE;
356	if (dev->flags & PNPBIOS_REMOVABLE)
357		dev->capabilities |= PNP_REMOVABLE;
358	dev->protocol = &pnpbios_protocol;
359
360	/* clear out the damaged flags */
361	if (!dev->active)
362		pnp_init_resource_table(&dev->res);
363
364	pnp_add_device(dev);
365	pnpbios_interface_attach_device(node);
366
367	return 0;
368}
369
370static void __init build_devlist(void)
371{
372	u8 nodenum;
373	unsigned int nodes_got = 0;
374	unsigned int devs = 0;
375	struct pnp_bios_node *node;
376	struct pnp_dev *dev;
377
378	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
379	if (!node)
380		return;
381
382	for(nodenum=0; nodenum<0xff; ) {
383		u8 thisnodenum = nodenum;
384		/* eventually we will want to use PNPMODE_STATIC here but for now
385		 * dynamic will help us catch buggy bioses to add to the blacklist.
386		 */
387		if (!pnpbios_dont_use_current_config) {
388			if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node))
389				break;
390		} else {
391			if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_STATIC, node))
392				break;
393		}
394		nodes_got++;
395		dev =  kcalloc(1, sizeof (struct pnp_dev), GFP_KERNEL);
396		if (!dev)
397			break;
398		if(insert_device(dev,node)<0)
399			kfree(dev);
400		else
401			devs++;
402		if (nodenum <= thisnodenum) {
403			printk(KERN_ERR "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n", (unsigned int)nodenum, (unsigned int)thisnodenum);
404			break;
405		}
406	}
407	kfree(node);
408
409	printk(KERN_INFO "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
410		nodes_got, nodes_got != 1 ? "s" : "", devs);
411}
412
413/*
414 *
415 * INIT AND EXIT
416 *
417 */
418
419static int pnpbios_disabled; /* = 0 */
420int pnpbios_dont_use_current_config; /* = 0 */
421
422#ifndef MODULE
423static int __init pnpbios_setup(char *str)
424{
425	int invert;
426
427	while ((str != NULL) && (*str != '\0')) {
428		if (strncmp(str, "off", 3) == 0)
429			pnpbios_disabled=1;
430		if (strncmp(str, "on", 2) == 0)
431			pnpbios_disabled=0;
432		invert = (strncmp(str, "no-", 3) == 0);
433		if (invert)
434			str += 3;
435		if (strncmp(str, "curr", 4) == 0)
436			pnpbios_dont_use_current_config = invert;
437		str = strchr(str, ',');
438		if (str != NULL)
439			str += strspn(str, ", \t");
440	}
441
442	return 1;
443}
444
445__setup("pnpbios=", pnpbios_setup);
446#endif
447
448/* PnP BIOS signature: "$PnP" */
449#define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
450
451static int __init pnpbios_probe_system(void)
452{
453	union pnp_bios_install_struct *check;
454	u8 sum;
455	int length, i;
456
457	printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
458
459	/*
460 	 * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
461	 * structure and, if one is found, sets up the selectors and
462	 * entry points
463	 */
464	for (check = (union pnp_bios_install_struct *) __va(0xf0000);
465	     check < (union pnp_bios_install_struct *) __va(0xffff0);
466	     check = (void *)check + 16) {
467		if (check->fields.signature != PNP_SIGNATURE)
468			continue;
469		printk(KERN_INFO "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n", check);
470		length = check->fields.length;
471		if (!length) {
472			printk(KERN_ERR "PnPBIOS: installation structure is invalid, skipping\n");
473			continue;
474		}
475		for (sum = 0, i = 0; i < length; i++)
476			sum += check->chars[i];
477		if (sum) {
478			printk(KERN_ERR "PnPBIOS: installation structure is corrupted, skipping\n");
479			continue;
480		}
481		if (check->fields.version < 0x10) {
482			printk(KERN_WARNING "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
483			       check->fields.version >> 4,
484			       check->fields.version & 15);
485			continue;
486		}
487		printk(KERN_INFO "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
488                       check->fields.version >> 4, check->fields.version & 15,
489		       check->fields.pm16cseg, check->fields.pm16offset,
490		       check->fields.pm16dseg);
491		pnp_bios_install = check;
492		return 1;
493	}
494
495	printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
496	return 0;
497}
498
499static int __init exploding_pnp_bios(struct dmi_system_id *d)
500{
501	printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
502	return 0;
503}
504
505static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
506	{	/* PnPBIOS GPF on boot */
507		.callback = exploding_pnp_bios,
508		.ident = "Higraded P14H",
509		.matches = {
510			DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
511			DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
512			DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
513			DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
514		},
515	},
516	{	/* PnPBIOS GPF on boot */
517		.callback = exploding_pnp_bios,
518		.ident = "ASUS P4P800",
519		.matches = {
520			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
521			DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
522		},
523	},
524	{ }
525};
526
527static int __init pnpbios_init(void)
528{
529	int ret;
530
531	if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table)) {
532		printk(KERN_INFO "PnPBIOS: Disabled\n");
533		return -ENODEV;
534	}
535
536#ifdef CONFIG_PNPACPI
537	if (!acpi_disabled && !pnpacpi_disabled) {
538		pnpbios_disabled = 1;
539		printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
540		return -ENODEV;
541	}
542#endif /* CONFIG_ACPI */
543
544	/* scan the system for pnpbios support */
545	if (!pnpbios_probe_system())
546		return -ENODEV;
547
548	/* make preparations for bios calls */
549	pnpbios_calls_init(pnp_bios_install);
550
551	/* read the node info */
552	ret = pnp_bios_dev_node_info(&node_info);
553	if (ret) {
554		printk(KERN_ERR "PnPBIOS: Unable to get node info.  Aborting.\n");
555		return ret;
556	}
557
558	/* register with the pnp layer */
559	ret = pnp_register_protocol(&pnpbios_protocol);
560	if (ret) {
561		printk(KERN_ERR "PnPBIOS: Unable to register driver.  Aborting.\n");
562		return ret;
563	}
564
565	/* start the proc interface */
566	ret = pnpbios_proc_init();
567	if (ret)
568		printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
569
570	/* scan for pnpbios devices */
571	build_devlist();
572
573	return 0;
574}
575
576subsys_initcall(pnpbios_init);
577
578static int __init pnpbios_thread_init(void)
579{
580	if (pnpbios_disabled)
581		return 0;
582#ifdef CONFIG_HOTPLUG
583	init_completion(&unload_sem);
584	if (kernel_thread(pnp_dock_thread, NULL, CLONE_KERNEL) > 0)
585		unloading = 0;
586#endif
587	return 0;
588}
589
590#ifndef MODULE
591
592/* init/main.c calls pnpbios_init early */
593
594/* Start the kernel thread later: */
595module_init(pnpbios_thread_init);
596
597#else
598
599/*
600 * N.B.: Building pnpbios as a module hasn't been fully implemented
601 */
602
603MODULE_LICENSE("GPL");
604
605static int __init pnpbios_init_all(void)
606{
607	int r;
608
609	r = pnpbios_init();
610	if (r)
611		return r;
612	r = pnpbios_thread_init();
613	if (r)
614		return r;
615	return 0;
616}
617
618static void __exit pnpbios_exit(void)
619{
620#ifdef CONFIG_HOTPLUG
621	unloading = 1;
622	wait_for_completion(&unload_sem);
623#endif
624	pnpbios_proc_exit();
625	/* We ought to free resources here */
626	return;
627}
628
629module_init(pnpbios_init_all);
630module_exit(pnpbios_exit);
631
632#endif
633
634EXPORT_SYMBOL(pnpbios_protocol);
635