Dont touch fs_struct in drivers
[linux-2.6.git] / drivers / pnp / pnpbios / core.c
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/completion.h>
60 #include <linux/spinlock.h>
61 #include <linux/dmi.h>
62 #include <linux/delay.h>
63 #include <linux/acpi.h>
64 #include <linux/freezer.h>
65 #include <linux/kthread.h>
66
67 #include <asm/page.h>
68 #include <asm/desc.h>
69 #include <asm/system.h>
70 #include <asm/byteorder.h>
71
72 #include "pnpbios.h"
73
74 /*
75  *
76  * PnP BIOS INTERFACE
77  *
78  */
79
80 static union pnp_bios_install_struct *pnp_bios_install = NULL;
81
82 int pnp_bios_present(void)
83 {
84         return (pnp_bios_install != NULL);
85 }
86
87 struct pnp_dev_node_info node_info;
88
89 /*
90  *
91  * DOCKING FUNCTIONS
92  *
93  */
94
95 #ifdef CONFIG_HOTPLUG
96
97 static int unloading = 0;
98 static struct completion unload_sem;
99
100 /*
101  * (Much of this belongs in a shared routine somewhere)
102  */
103 static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
104 {
105         char *argv[3], **envp, *buf, *scratch;
106         int i = 0, value;
107
108         if (!(envp = kcalloc(20, sizeof(char *), GFP_KERNEL)))
109                 return -ENOMEM;
110         if (!(buf = kzalloc(256, GFP_KERNEL))) {
111                 kfree(envp);
112                 return -ENOMEM;
113         }
114
115         /* FIXME: if there are actual users of this, it should be
116          * integrated into the driver core and use the usual infrastructure
117          * like sysfs and uevents
118          */
119         argv[0] = "/sbin/pnpbios";
120         argv[1] = "dock";
121         argv[2] = NULL;
122
123         /* minimal command environment */
124         envp[i++] = "HOME=/";
125         envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
126
127 #ifdef  DEBUG
128         /* hint that policy agent should enter no-stdout debug mode */
129         envp[i++] = "DEBUG=kernel";
130 #endif
131         /* extensible set of named bus-specific parameters,
132          * supporting multiple driver selection algorithms.
133          */
134         scratch = buf;
135
136         /* action:  add, remove */
137         envp[i++] = scratch;
138         scratch += sprintf(scratch, "ACTION=%s", dock ? "add" : "remove") + 1;
139
140         /* Report the ident for the dock */
141         envp[i++] = scratch;
142         scratch += sprintf(scratch, "DOCK=%x/%x/%x",
143                            info->location_id, info->serial, info->capabilities);
144         envp[i] = NULL;
145
146         value = call_usermodehelper(argv [0], argv, envp, UMH_WAIT_EXEC);
147         kfree(buf);
148         kfree(envp);
149         return 0;
150 }
151
152 /*
153  * Poll the PnP docking at regular intervals
154  */
155 static int pnp_dock_thread(void *unused)
156 {
157         static struct pnp_docking_station_info now;
158         int docked = -1, d = 0;
159
160         set_freezable();
161         while (!unloading) {
162                 int status;
163
164                 /*
165                  * Poll every 2 seconds
166                  */
167                 msleep_interruptible(2000);
168
169                 if (try_to_freeze())
170                         continue;
171
172                 status = pnp_bios_dock_station_info(&now);
173
174                 switch (status) {
175                         /*
176                          * No dock to manage
177                          */
178                 case PNP_FUNCTION_NOT_SUPPORTED:
179                         complete_and_exit(&unload_sem, 0);
180                 case PNP_SYSTEM_NOT_DOCKED:
181                         d = 0;
182                         break;
183                 case PNP_SUCCESS:
184                         d = 1;
185                         break;
186                 default:
187                         pnpbios_print_status("pnp_dock_thread", status);
188                         continue;
189                 }
190                 if (d != docked) {
191                         if (pnp_dock_event(d, &now) == 0) {
192                                 docked = d;
193 #if 0
194                                 printk(KERN_INFO
195                                        "PnPBIOS: Docking station %stached\n",
196                                        docked ? "at" : "de");
197 #endif
198                         }
199                 }
200         }
201         complete_and_exit(&unload_sem, 0);
202 }
203
204 #endif                          /* CONFIG_HOTPLUG */
205
206 static int pnpbios_get_resources(struct pnp_dev *dev,
207                                  struct pnp_resource_table *res)
208 {
209         u8 nodenum = dev->number;
210         struct pnp_bios_node *node;
211
212         if (!pnpbios_is_dynamic(dev))
213                 return -EPERM;
214
215         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
216         if (!node)
217                 return -1;
218         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
219                 kfree(node);
220                 return -ENODEV;
221         }
222         pnpbios_read_resources_from_node(res, node);
223         dev->active = pnp_is_active(dev);
224         kfree(node);
225         return 0;
226 }
227
228 static int pnpbios_set_resources(struct pnp_dev *dev,
229                                  struct pnp_resource_table *res)
230 {
231         u8 nodenum = dev->number;
232         struct pnp_bios_node *node;
233         int ret;
234
235         if (!pnpbios_is_dynamic(dev))
236                 return -EPERM;
237
238         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
239         if (!node)
240                 return -1;
241         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
242                 kfree(node);
243                 return -ENODEV;
244         }
245         if (pnpbios_write_resources_to_node(res, node) < 0) {
246                 kfree(node);
247                 return -1;
248         }
249         ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
250         kfree(node);
251         if (ret > 0)
252                 ret = -1;
253         return ret;
254 }
255
256 static void pnpbios_zero_data_stream(struct pnp_bios_node *node)
257 {
258         unsigned char *p = (char *)node->data;
259         unsigned char *end = (char *)(node->data + node->size);
260         unsigned int len;
261         int i;
262
263         while ((char *)p < (char *)end) {
264                 if (p[0] & 0x80) {      /* large tag */
265                         len = (p[2] << 8) | p[1];
266                         p += 3;
267                 } else {
268                         if (((p[0] >> 3) & 0x0f) == 0x0f)
269                                 return;
270                         len = p[0] & 0x07;
271                         p += 1;
272                 }
273                 for (i = 0; i < len; i++)
274                         p[i] = 0;
275                 p += len;
276         }
277         printk(KERN_ERR
278                "PnPBIOS: Resource structure did not contain an end tag.\n");
279 }
280
281 static int pnpbios_disable_resources(struct pnp_dev *dev)
282 {
283         struct pnp_bios_node *node;
284         u8 nodenum = dev->number;
285         int ret;
286
287         if (dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
288                 return -EPERM;
289
290         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
291         if (!node)
292                 return -ENOMEM;
293
294         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
295                 kfree(node);
296                 return -ENODEV;
297         }
298         pnpbios_zero_data_stream(node);
299
300         ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
301         kfree(node);
302         if (ret > 0)
303                 ret = -1;
304         return ret;
305 }
306
307 /* PnP Layer support */
308
309 struct pnp_protocol pnpbios_protocol = {
310         .name = "Plug and Play BIOS",
311         .get = pnpbios_get_resources,
312         .set = pnpbios_set_resources,
313         .disable = pnpbios_disable_resources,
314 };
315
316 static int __init insert_device(struct pnp_bios_node *node)
317 {
318         struct list_head *pos;
319         struct pnp_dev *dev;
320         struct pnp_id *dev_id;
321         char id[8];
322
323         /* check if the device is already added */
324         list_for_each(pos, &pnpbios_protocol.devices) {
325                 dev = list_entry(pos, struct pnp_dev, protocol_list);
326                 if (dev->number == node->handle)
327                         return -1;
328         }
329
330         dev = kzalloc(sizeof(struct pnp_dev), GFP_KERNEL);
331         if (!dev)
332                 return -1;
333
334         dev_id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
335         if (!dev_id) {
336                 kfree(dev);
337                 return -1;
338         }
339
340         dev->number = node->handle;
341         pnpid32_to_pnpid(node->eisa_id, id);
342         memcpy(dev_id->id, id, 7);
343         pnp_add_id(dev_id, dev);
344         pnpbios_parse_data_stream(dev, node);
345         dev->active = pnp_is_active(dev);
346         dev->flags = node->flags;
347         if (!(dev->flags & PNPBIOS_NO_CONFIG))
348                 dev->capabilities |= PNP_CONFIGURABLE;
349         if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
350                 dev->capabilities |= PNP_DISABLE;
351         dev->capabilities |= PNP_READ;
352         if (pnpbios_is_dynamic(dev))
353                 dev->capabilities |= PNP_WRITE;
354         if (dev->flags & PNPBIOS_REMOVABLE)
355                 dev->capabilities |= PNP_REMOVABLE;
356         dev->protocol = &pnpbios_protocol;
357
358         /* clear out the damaged flags */
359         if (!dev->active)
360                 pnp_init_resource_table(&dev->res);
361
362         pnp_add_device(dev);
363         pnpbios_interface_attach_device(node);
364
365         return 0;
366 }
367
368 static void __init build_devlist(void)
369 {
370         u8 nodenum;
371         unsigned int nodes_got = 0;
372         unsigned int devs = 0;
373         struct pnp_bios_node *node;
374
375         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
376         if (!node)
377                 return;
378
379         for (nodenum = 0; nodenum < 0xff;) {
380                 u8 thisnodenum = nodenum;
381                 /* eventually we will want to use PNPMODE_STATIC here but for now
382                  * dynamic will help us catch buggy bioses to add to the blacklist.
383                  */
384                 if (!pnpbios_dont_use_current_config) {
385                         if (pnp_bios_get_dev_node
386                             (&nodenum, (char)PNPMODE_DYNAMIC, node))
387                                 break;
388                 } else {
389                         if (pnp_bios_get_dev_node
390                             (&nodenum, (char)PNPMODE_STATIC, node))
391                                 break;
392                 }
393                 nodes_got++;
394                 if (insert_device(node) == 0)
395                         devs++;
396                 if (nodenum <= thisnodenum) {
397                         printk(KERN_ERR
398                                "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
399                                (unsigned int)nodenum,
400                                (unsigned int)thisnodenum);
401                         break;
402                 }
403         }
404         kfree(node);
405
406         printk(KERN_INFO
407                "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
408                nodes_got, nodes_got != 1 ? "s" : "", devs);
409 }
410
411 /*
412  *
413  * INIT AND EXIT
414  *
415  */
416
417 static int pnpbios_disabled;
418 int pnpbios_dont_use_current_config;
419
420 static int __init pnpbios_setup(char *str)
421 {
422         int invert;
423
424         while ((str != NULL) && (*str != '\0')) {
425                 if (strncmp(str, "off", 3) == 0)
426                         pnpbios_disabled = 1;
427                 if (strncmp(str, "on", 2) == 0)
428                         pnpbios_disabled = 0;
429                 invert = (strncmp(str, "no-", 3) == 0);
430                 if (invert)
431                         str += 3;
432                 if (strncmp(str, "curr", 4) == 0)
433                         pnpbios_dont_use_current_config = invert;
434                 str = strchr(str, ',');
435                 if (str != NULL)
436                         str += strspn(str, ", \t");
437         }
438
439         return 1;
440 }
441
442 __setup("pnpbios=", pnpbios_setup);
443
444 /* PnP BIOS signature: "$PnP" */
445 #define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
446
447 static int __init pnpbios_probe_system(void)
448 {
449         union pnp_bios_install_struct *check;
450         u8 sum;
451         int length, i;
452
453         printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
454
455         /*
456          * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
457          * structure and, if one is found, sets up the selectors and
458          * entry points
459          */
460         for (check = (union pnp_bios_install_struct *)__va(0xf0000);
461              check < (union pnp_bios_install_struct *)__va(0xffff0);
462              check = (void *)check + 16) {
463                 if (check->fields.signature != PNP_SIGNATURE)
464                         continue;
465                 printk(KERN_INFO
466                        "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
467                        check);
468                 length = check->fields.length;
469                 if (!length) {
470                         printk(KERN_ERR
471                                "PnPBIOS: installation structure is invalid, skipping\n");
472                         continue;
473                 }
474                 for (sum = 0, i = 0; i < length; i++)
475                         sum += check->chars[i];
476                 if (sum) {
477                         printk(KERN_ERR
478                                "PnPBIOS: installation structure is corrupted, skipping\n");
479                         continue;
480                 }
481                 if (check->fields.version < 0x10) {
482                         printk(KERN_WARNING
483                                "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
484                                check->fields.version >> 4,
485                                check->fields.version & 15);
486                         continue;
487                 }
488                 printk(KERN_INFO
489                        "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
490                        check->fields.version >> 4, check->fields.version & 15,
491                        check->fields.pm16cseg, check->fields.pm16offset,
492                        check->fields.pm16dseg);
493                 pnp_bios_install = check;
494                 return 1;
495         }
496
497         printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
498         return 0;
499 }
500
501 static int __init exploding_pnp_bios(const struct dmi_system_id *d)
502 {
503         printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
504         return 0;
505 }
506
507 static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
508         {                       /* PnPBIOS GPF on boot */
509          .callback = exploding_pnp_bios,
510          .ident = "Higraded P14H",
511          .matches = {
512                      DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
513                      DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
514                      DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
515                      DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
516                      },
517          },
518         {                       /* PnPBIOS GPF on boot */
519          .callback = exploding_pnp_bios,
520          .ident = "ASUS P4P800",
521          .matches = {
522                      DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
523                      DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
524                      },
525          },
526         {}
527 };
528
529 static int __init pnpbios_init(void)
530 {
531         int ret;
532
533 #if defined(CONFIG_PPC_MERGE)
534         if (check_legacy_ioport(PNPBIOS_BASE))
535                 return -ENODEV;
536 #endif
537         if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
538             paravirt_enabled()) {
539                 printk(KERN_INFO "PnPBIOS: Disabled\n");
540                 return -ENODEV;
541         }
542 #ifdef CONFIG_PNPACPI
543         if (!acpi_disabled && !pnpacpi_disabled) {
544                 pnpbios_disabled = 1;
545                 printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
546                 return -ENODEV;
547         }
548 #endif                          /* CONFIG_ACPI */
549
550         /* scan the system for pnpbios support */
551         if (!pnpbios_probe_system())
552                 return -ENODEV;
553
554         /* make preparations for bios calls */
555         pnpbios_calls_init(pnp_bios_install);
556
557         /* read the node info */
558         ret = pnp_bios_dev_node_info(&node_info);
559         if (ret) {
560                 printk(KERN_ERR
561                        "PnPBIOS: Unable to get node info.  Aborting.\n");
562                 return ret;
563         }
564
565         /* register with the pnp layer */
566         ret = pnp_register_protocol(&pnpbios_protocol);
567         if (ret) {
568                 printk(KERN_ERR
569                        "PnPBIOS: Unable to register driver.  Aborting.\n");
570                 return ret;
571         }
572
573         /* start the proc interface */
574         ret = pnpbios_proc_init();
575         if (ret)
576                 printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
577
578         /* scan for pnpbios devices */
579         build_devlist();
580
581         pnp_platform_devices = 1;
582         return 0;
583 }
584
585 subsys_initcall(pnpbios_init);
586
587 static int __init pnpbios_thread_init(void)
588 {
589         struct task_struct *task;
590
591 #if defined(CONFIG_PPC_MERGE)
592         if (check_legacy_ioport(PNPBIOS_BASE))
593                 return 0;
594 #endif
595         if (pnpbios_disabled)
596                 return 0;
597 #ifdef CONFIG_HOTPLUG
598         init_completion(&unload_sem);
599         task = kthread_run(pnp_dock_thread, NULL, "kpnpbiosd");
600         if (!IS_ERR(task))
601                 unloading = 0;
602 #endif
603         return 0;
604 }
605
606 /* Start the kernel thread later: */
607 module_init(pnpbios_thread_init);
608
609 EXPORT_SYMBOL(pnpbios_protocol);