core.c revision d8254e0e72c8cc6131f789f8645338b719f57648 
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/device.h>
54#include <linux/pnp.h>
55#include <linux/mm.h>
56#include <linux/smp.h>
57#include <linux/slab.h>
58#include <linux/completion.h>
59#include <linux/spinlock.h>
60#include <linux/dmi.h>
61#include <linux/delay.h>
62#include <linux/acpi.h>
63#include <linux/freezer.h>
64#include <linux/kthread.h>
65
66#include <asm/page.h>
67#include <asm/desc.h>
68#include <asm/byteorder.h>
69
70#include "../base.h"
71#include "pnpbios.h"
72
73/*
74 *
75 * PnP BIOS INTERFACE
76 *
77 */
78
79static union pnp_bios_install_struct *pnp_bios_install = NULL;
80
81int pnp_bios_present(void)
82{
83	return (pnp_bios_install != NULL);
84}
85
86struct pnp_dev_node_info node_info;
87
88/*
89 *
90 * DOCKING FUNCTIONS
91 *
92 */
93
94static struct completion unload_sem;
95
96/*
97 * (Much of this belongs in a shared routine somewhere)
98 */
99static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
100{
101	char *argv[3], **envp, *buf, *scratch;
102	int i = 0, value;
103
104	if (!(envp = kcalloc(20, sizeof(char *), GFP_KERNEL)))
105		return -ENOMEM;
106	if (!(buf = kzalloc(256, GFP_KERNEL))) {
107		kfree(envp);
108		return -ENOMEM;
109	}
110
111	/* FIXME: if there are actual users of this, it should be
112	 * integrated into the driver core and use the usual infrastructure
113	 * like sysfs and uevents
114	 */
115	argv[0] = "/sbin/pnpbios";
116	argv[1] = "dock";
117	argv[2] = NULL;
118
119	/* minimal command environment */
120	envp[i++] = "HOME=/";
121	envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
122
123#ifdef	DEBUG
124	/* hint that policy agent should enter no-stdout debug mode */
125	envp[i++] = "DEBUG=kernel";
126#endif
127	/* extensible set of named bus-specific parameters,
128	 * supporting multiple driver selection algorithms.
129	 */
130	scratch = buf;
131
132	/* action:  add, remove */
133	envp[i++] = scratch;
134	scratch += sprintf(scratch, "ACTION=%s", dock ? "add" : "remove") + 1;
135
136	/* Report the ident for the dock */
137	envp[i++] = scratch;
138	scratch += sprintf(scratch, "DOCK=%x/%x/%x",
139			   info->location_id, info->serial, info->capabilities);
140	envp[i] = NULL;
141
142	value = call_usermodehelper(argv [0], argv, envp, UMH_WAIT_EXEC);
143	kfree(buf);
144	kfree(envp);
145	return 0;
146}
147
148/*
149 * Poll the PnP docking at regular intervals
150 */
151static int pnp_dock_thread(void *unused)
152{
153	static struct pnp_docking_station_info now;
154	int docked = -1, d = 0;
155
156	set_freezable();
157	while (1) {
158		int status;
159
160		/*
161		 * Poll every 2 seconds
162		 */
163		msleep_interruptible(2000);
164
165		if (try_to_freeze())
166			continue;
167
168		status = pnp_bios_dock_station_info(&now);
169
170		switch (status) {
171			/*
172			 * No dock to manage
173			 */
174		case PNP_FUNCTION_NOT_SUPPORTED:
175			complete_and_exit(&unload_sem, 0);
176		case PNP_SYSTEM_NOT_DOCKED:
177			d = 0;
178			break;
179		case PNP_SUCCESS:
180			d = 1;
181			break;
182		default:
183			pnpbios_print_status("pnp_dock_thread", status);
184			continue;
185		}
186		if (d != docked) {
187			if (pnp_dock_event(d, &now) == 0) {
188				docked = d;
189#if 0
190				printk(KERN_INFO
191				       "PnPBIOS: Docking station %stached\n",
192				       docked ? "at" : "de");
193#endif
194			}
195		}
196	}
197	complete_and_exit(&unload_sem, 0);
198}
199
200static int pnpbios_get_resources(struct pnp_dev *dev)
201{
202	u8 nodenum = dev->number;
203	struct pnp_bios_node *node;
204
205	if (!pnpbios_is_dynamic(dev))
206		return -EPERM;
207
208	pnp_dbg(&dev->dev, "get resources\n");
209	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
210	if (!node)
211		return -1;
212	if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
213		kfree(node);
214		return -ENODEV;
215	}
216	pnpbios_read_resources_from_node(dev, node);
217	dev->active = pnp_is_active(dev);
218	kfree(node);
219	return 0;
220}
221
222static int pnpbios_set_resources(struct pnp_dev *dev)
223{
224	u8 nodenum = dev->number;
225	struct pnp_bios_node *node;
226	int ret;
227
228	if (!pnpbios_is_dynamic(dev))
229		return -EPERM;
230
231	pnp_dbg(&dev->dev, "set resources\n");
232	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
233	if (!node)
234		return -1;
235	if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
236		kfree(node);
237		return -ENODEV;
238	}
239	if (pnpbios_write_resources_to_node(dev, node) < 0) {
240		kfree(node);
241		return -1;
242	}
243	ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
244	kfree(node);
245	if (ret > 0)
246		ret = -1;
247	return ret;
248}
249
250static void pnpbios_zero_data_stream(struct pnp_bios_node *node)
251{
252	unsigned char *p = (char *)node->data;
253	unsigned char *end = (char *)(node->data + node->size);
254	unsigned int len;
255	int i;
256
257	while ((char *)p < (char *)end) {
258		if (p[0] & 0x80) {	/* large tag */
259			len = (p[2] << 8) | p[1];
260			p += 3;
261		} else {
262			if (((p[0] >> 3) & 0x0f) == 0x0f)
263				return;
264			len = p[0] & 0x07;
265			p += 1;
266		}
267		for (i = 0; i < len; i++)
268			p[i] = 0;
269		p += len;
270	}
271	printk(KERN_ERR
272	       "PnPBIOS: Resource structure did not contain an end tag.\n");
273}
274
275static int pnpbios_disable_resources(struct pnp_dev *dev)
276{
277	struct pnp_bios_node *node;
278	u8 nodenum = dev->number;
279	int ret;
280
281	if (dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
282		return -EPERM;
283
284	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
285	if (!node)
286		return -ENOMEM;
287
288	if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
289		kfree(node);
290		return -ENODEV;
291	}
292	pnpbios_zero_data_stream(node);
293
294	ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
295	kfree(node);
296	if (ret > 0)
297		ret = -1;
298	return ret;
299}
300
301/* PnP Layer support */
302
303struct pnp_protocol pnpbios_protocol = {
304	.name = "Plug and Play BIOS",
305	.get = pnpbios_get_resources,
306	.set = pnpbios_set_resources,
307	.disable = pnpbios_disable_resources,
308};
309
310static int __init insert_device(struct pnp_bios_node *node)
311{
312	struct list_head *pos;
313	struct pnp_dev *dev;
314	char id[8];
315	int error;
316
317	/* check if the device is already added */
318	list_for_each(pos, &pnpbios_protocol.devices) {
319		dev = list_entry(pos, struct pnp_dev, protocol_list);
320		if (dev->number == node->handle)
321			return -EEXIST;
322	}
323
324	pnp_eisa_id_to_string(node->eisa_id & PNP_EISA_ID_MASK, id);
325	dev = pnp_alloc_dev(&pnpbios_protocol, node->handle, id);
326	if (!dev)
327		return -ENOMEM;
328
329	pnpbios_parse_data_stream(dev, node);
330	dev->active = pnp_is_active(dev);
331	dev->flags = node->flags;
332	if (!(dev->flags & PNPBIOS_NO_CONFIG))
333		dev->capabilities |= PNP_CONFIGURABLE;
334	if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
335		dev->capabilities |= PNP_DISABLE;
336	dev->capabilities |= PNP_READ;
337	if (pnpbios_is_dynamic(dev))
338		dev->capabilities |= PNP_WRITE;
339	if (dev->flags & PNPBIOS_REMOVABLE)
340		dev->capabilities |= PNP_REMOVABLE;
341
342	/* clear out the damaged flags */
343	if (!dev->active)
344		pnp_init_resources(dev);
345
346	error = pnp_add_device(dev);
347	if (error) {
348		put_device(&dev->dev);
349		return error;
350	}
351
352	pnpbios_interface_attach_device(node);
353
354	return 0;
355}
356
357static void __init build_devlist(void)
358{
359	u8 nodenum;
360	unsigned int nodes_got = 0;
361	unsigned int devs = 0;
362	struct pnp_bios_node *node;
363
364	node = kzalloc(node_info.max_node_size, GFP_KERNEL);
365	if (!node)
366		return;
367
368	for (nodenum = 0; nodenum < 0xff;) {
369		u8 thisnodenum = nodenum;
370		/* eventually we will want to use PNPMODE_STATIC here but for now
371		 * dynamic will help us catch buggy bioses to add to the blacklist.
372		 */
373		if (!pnpbios_dont_use_current_config) {
374			if (pnp_bios_get_dev_node
375			    (&nodenum, (char)PNPMODE_DYNAMIC, node))
376				break;
377		} else {
378			if (pnp_bios_get_dev_node
379			    (&nodenum, (char)PNPMODE_STATIC, node))
380				break;
381		}
382		nodes_got++;
383		if (insert_device(node) == 0)
384			devs++;
385		if (nodenum <= thisnodenum) {
386			printk(KERN_ERR
387			       "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
388			       (unsigned int)nodenum,
389			       (unsigned int)thisnodenum);
390			break;
391		}
392	}
393	kfree(node);
394
395	printk(KERN_INFO
396	       "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
397	       nodes_got, nodes_got != 1 ? "s" : "", devs);
398}
399
400/*
401 *
402 * INIT AND EXIT
403 *
404 */
405
406static int pnpbios_disabled;
407int pnpbios_dont_use_current_config;
408
409static int __init pnpbios_setup(char *str)
410{
411	int invert;
412
413	while ((str != NULL) && (*str != '\0')) {
414		if (strncmp(str, "off", 3) == 0)
415			pnpbios_disabled = 1;
416		if (strncmp(str, "on", 2) == 0)
417			pnpbios_disabled = 0;
418		invert = (strncmp(str, "no-", 3) == 0);
419		if (invert)
420			str += 3;
421		if (strncmp(str, "curr", 4) == 0)
422			pnpbios_dont_use_current_config = invert;
423		str = strchr(str, ',');
424		if (str != NULL)
425			str += strspn(str, ", \t");
426	}
427
428	return 1;
429}
430
431__setup("pnpbios=", pnpbios_setup);
432
433/* PnP BIOS signature: "$PnP" */
434#define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
435
436static int __init pnpbios_probe_system(void)
437{
438	union pnp_bios_install_struct *check;
439	u8 sum;
440	int length, i;
441
442	printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
443
444	/*
445	 * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
446	 * structure and, if one is found, sets up the selectors and
447	 * entry points
448	 */
449	for (check = (union pnp_bios_install_struct *)__va(0xf0000);
450	     check < (union pnp_bios_install_struct *)__va(0xffff0);
451	     check = (void *)check + 16) {
452		if (check->fields.signature != PNP_SIGNATURE)
453			continue;
454		printk(KERN_INFO
455		       "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
456		       check);
457		length = check->fields.length;
458		if (!length) {
459			printk(KERN_ERR
460			       "PnPBIOS: installation structure is invalid, skipping\n");
461			continue;
462		}
463		for (sum = 0, i = 0; i < length; i++)
464			sum += check->chars[i];
465		if (sum) {
466			printk(KERN_ERR
467			       "PnPBIOS: installation structure is corrupted, skipping\n");
468			continue;
469		}
470		if (check->fields.version < 0x10) {
471			printk(KERN_WARNING
472			       "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
473			       check->fields.version >> 4,
474			       check->fields.version & 15);
475			continue;
476		}
477		printk(KERN_INFO
478		       "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
479		       check->fields.version >> 4, check->fields.version & 15,
480		       check->fields.pm16cseg, check->fields.pm16offset,
481		       check->fields.pm16dseg);
482		pnp_bios_install = check;
483		return 1;
484	}
485
486	printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
487	return 0;
488}
489
490static int __init exploding_pnp_bios(const struct dmi_system_id *d)
491{
492	printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
493	return 0;
494}
495
496static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
497	{			/* PnPBIOS GPF on boot */
498	 .callback = exploding_pnp_bios,
499	 .ident = "Higraded P14H",
500	 .matches = {
501		     DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
502		     DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
503		     DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
504		     DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
505		     },
506	 },
507	{			/* PnPBIOS GPF on boot */
508	 .callback = exploding_pnp_bios,
509	 .ident = "ASUS P4P800",
510	 .matches = {
511		     DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
512		     DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
513		     },
514	 },
515	{}
516};
517
518static int __init pnpbios_init(void)
519{
520	int ret;
521
522	if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
523	    paravirt_enabled()) {
524		printk(KERN_INFO "PnPBIOS: Disabled\n");
525		return -ENODEV;
526	}
527#ifdef CONFIG_PNPACPI
528	if (!acpi_disabled && !pnpacpi_disabled) {
529		pnpbios_disabled = 1;
530		printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
531		return -ENODEV;
532	}
533#endif				/* CONFIG_ACPI */
534
535	/* scan the system for pnpbios support */
536	if (!pnpbios_probe_system())
537		return -ENODEV;
538
539	/* make preparations for bios calls */
540	pnpbios_calls_init(pnp_bios_install);
541
542	/* read the node info */
543	ret = pnp_bios_dev_node_info(&node_info);
544	if (ret) {
545		printk(KERN_ERR
546		       "PnPBIOS: Unable to get node info.  Aborting.\n");
547		return ret;
548	}
549
550	/* register with the pnp layer */
551	ret = pnp_register_protocol(&pnpbios_protocol);
552	if (ret) {
553		printk(KERN_ERR
554		       "PnPBIOS: Unable to register driver.  Aborting.\n");
555		return ret;
556	}
557
558	/* start the proc interface */
559	ret = pnpbios_proc_init();
560	if (ret)
561		printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
562
563	/* scan for pnpbios devices */
564	build_devlist();
565
566	pnp_platform_devices = 1;
567	return 0;
568}
569
570fs_initcall(pnpbios_init);
571
572static int __init pnpbios_thread_init(void)
573{
574	struct task_struct *task;
575
576	if (pnpbios_disabled)
577		return 0;
578
579	init_completion(&unload_sem);
580	task = kthread_run(pnp_dock_thread, NULL, "kpnpbiosd");
581	if (IS_ERR(task))
582		return PTR_ERR(task);
583
584	return 0;
585}
586
587/* Start the kernel thread later: */
588module_init(pnpbios_thread_init);
589
590EXPORT_SYMBOL(pnpbios_protocol);
591