drivers/pnp/pnpbios/core.c - maze/linux - Git at Google

 /*
  * pnpbios -- PnP BIOS driver
  *
  * This driver provides access to Plug-'n'-Play services provided by
  * the PnP BIOS firmware, described in the following documents:
  *   Plug and Play BIOS Specification, Version 1.0A, 5 May 1994
  *   Plug and Play BIOS Clarification Paper, 6 October 1994
  *     Compaq Computer Corporation, Phoenix Technologies Ltd., Intel Corp.
  *
  * Originally (C) 1998 Christian Schmidt <schmidt@digadd.de>
  * Modifications (C) 1998 Tom Lees <tom@lpsg.demon.co.uk>
  * Minor reorganizations by David Hinds <dahinds@users.sourceforge.net>
  * Further modifications (C) 2001, 2002 by:
  *   Alan Cox <alan@redhat.com>
  *   Thomas Hood
  *   Brian Gerst <bgerst@didntduck.org>
  *
  * Ported to the PnP Layer and several additional improvements (C) 2002
  * by Adam Belay <ambx1@neo.rr.com>
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the
  * Free Software Foundation; either version 2, or (at your option) any
  * later version.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */

 /* Change Log
  *
  * Adam Belay - <ambx1@neo.rr.com> - March 16, 2003
  * rev 1.01	Only call pnp_bios_dev_node_info once
  *		Added pnpbios_print_status
  *		Added several new error messages and info messages
  *		Added pnpbios_interface_attach_device
  *		integrated core and proc init system
  *		Introduced PNPMODE flags
  *		Removed some useless includes
  */

 #include <linux/types.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/linkage.h>
 #include <linux/kernel.h>
 #include <linux/pnpbios.h>
 #include <linux/device.h>
 #include <linux/pnp.h>
 #include <linux/mm.h>
 #include <linux/smp.h>
 #include <linux/slab.h>
 #include <linux/completion.h>
 #include <linux/spinlock.h>
 #include <linux/dmi.h>
 #include <linux/delay.h>
 #include <linux/acpi.h>

 #include <asm/page.h>
 #include <asm/desc.h>
 #include <asm/system.h>
 #include <asm/byteorder.h>

 #include "pnpbios.h"


 /*
  *
  * PnP BIOS INTERFACE
  *
  */

 static union pnp_bios_install_struct * pnp_bios_install = NULL;

 int pnp_bios_present(void)
 {
 	return (pnp_bios_install != NULL);
 }

 struct pnp_dev_node_info node_info;

 /*
  *
  * DOCKING FUNCTIONS
  *
  */

 #ifdef CONFIG_HOTPLUG

 static int unloading = 0;
 static struct completion unload_sem;

 /*
  * (Much of this belongs in a shared routine somewhere)
  */

 static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
 {
 	char *argv [3], **envp, *buf, *scratch;
 	int i = 0, value;

 	if (!current->fs->root) {
 		return -EAGAIN;
 	}
 	if (!(envp = (char **) kcalloc (20, sizeof (char *), GFP_KERNEL))) {
 		return -ENOMEM;
 	}
 	if (!(buf = kcalloc (1, 256, GFP_KERNEL))) {
 		kfree (envp);
 		return -ENOMEM;
 	}

 	/* FIXME: if there are actual users of this, it should be integrated into
 	 * the driver core and use the usual infrastructure like sysfs and uevents */
 	argv [0] = "/sbin/pnpbios";
 	argv [1] = "dock";
 	argv [2] = NULL;

 	/* minimal command environment */
 	envp [i++] = "HOME=/";
 	envp [i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";

 #ifdef	DEBUG
 	/* hint that policy agent should enter no-stdout debug mode */
 	envp [i++] = "DEBUG=kernel";
 #endif
 	/* extensible set of named bus-specific parameters,
 	 * supporting multiple driver selection algorithms.
 	 */
 	scratch = buf;

 	/* action:  add, remove */
 	envp [i++] = scratch;
 	scratch += sprintf (scratch, "ACTION=%s", dock?"add":"remove") + 1;

 	/* Report the ident for the dock */
 	envp [i++] = scratch;
 	scratch += sprintf (scratch, "DOCK=%x/%x/%x",
 		info->location_id, info->serial, info->capabilities);
 	envp[i] = NULL;

 	value = call_usermodehelper (argv [0], argv, envp, 0);
 	kfree (buf);
 	kfree (envp);
 	return 0;
 }

 /*
  * Poll the PnP docking at regular intervals
  */
 static int pnp_dock_thread(void * unused)
 {
 	static struct pnp_docking_station_info now;
 	int docked = -1, d = 0;
 	daemonize("kpnpbiosd");
 	allow_signal(SIGKILL);
 	while(!unloading && !signal_pending(current))
 	{
 		int status;

 		/*
 		 * Poll every 2 seconds
 		 */
 		msleep_interruptible(2000);

 		if(signal_pending(current)) {
 			if (try_to_freeze())
 				continue;
 			break;
 		}

 		status = pnp_bios_dock_station_info(&now);

 		switch(status)
 		{
 			/*
 			 * No dock to manage
 			 */
 			case PNP_FUNCTION_NOT_SUPPORTED:
 				complete_and_exit(&unload_sem, 0);
 			case PNP_SYSTEM_NOT_DOCKED:
 				d = 0;
 				break;
 			case PNP_SUCCESS:
 				d = 1;
 				break;
 			default:
 				pnpbios_print_status( "pnp_dock_thread", status );
 				continue;
 		}
 		if(d != docked)
 		{
 			if(pnp_dock_event(d, &now)==0)
 			{
 				docked = d;
 #if 0
 				printk(KERN_INFO "PnPBIOS: Docking station %stached\n", docked?"at":"de");
 #endif
 			}
 		}
 	}
 	complete_and_exit(&unload_sem, 0);
 }

 #endif   /* CONFIG_HOTPLUG */

 static int pnpbios_get_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
 {
 	u8 nodenum = dev->number;
 	struct pnp_bios_node * node;

 	/* just in case */
 	if(!pnpbios_is_dynamic(dev))
 		return -EPERM;

 	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
 	if (!node)
 		return -1;
 	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
 		kfree(node);
 		return -ENODEV;
 	}
 	pnpbios_read_resources_from_node(res, node);
 	dev->active = pnp_is_active(dev);
 	kfree(node);
 	return 0;
 }

 static int pnpbios_set_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
 {
 	u8 nodenum = dev->number;
 	struct pnp_bios_node * node;
 	int ret;

 	/* just in case */
 	if (!pnpbios_is_dynamic(dev))
 		return -EPERM;

 	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
 	if (!node)
 		return -1;
 	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
 		kfree(node);
 		return -ENODEV;
 	}
 	if(pnpbios_write_resources_to_node(res, node)<0) {
 		kfree(node);
 		return -1;
 	}
 	ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
 	kfree(node);
 	if (ret > 0)
 		ret = -1;
 	return ret;
 }

 static void pnpbios_zero_data_stream(struct pnp_bios_node * node)
 {
 	unsigned char * p = (char *)node->data;
 	unsigned char * end = (char *)(node->data + node->size);
 	unsigned int len;
 	int i;
 	while ((char *)p < (char *)end) {
 		if(p[0] & 0x80) { /* large tag */
 			len = (p[2] << 8) | p[1];
 			p += 3;
 		} else {
 			if (((p[0]>>3) & 0x0f) == 0x0f)
 				return;
 			len = p[0] & 0x07;
 			p += 1;
 		}
 		for (i = 0; i < len; i++)
 			p[i] = 0;
 		p += len;
 	}
 	printk(KERN_ERR "PnPBIOS: Resource structure did not contain an end tag.\n");
 }

 static int pnpbios_disable_resources(struct pnp_dev *dev)
 {
 	struct pnp_bios_node * node;
 	u8 nodenum = dev->number;
 	int ret;

 	/* just in case */
 	if(dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
 		return -EPERM;

 	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
 	if (!node)
 		return -ENOMEM;

 	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
 		kfree(node);
 		return -ENODEV;
 	}
 	pnpbios_zero_data_stream(node);

 	ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
 	kfree(node);
 	if (ret > 0)
 		ret = -1;
 	return ret;
 }

 /* PnP Layer support */

 struct pnp_protocol pnpbios_protocol = {
 	.name	= "Plug and Play BIOS",
 	.get	= pnpbios_get_resources,
 	.set	= pnpbios_set_resources,
 	.disable = pnpbios_disable_resources,
 };

 static int insert_device(struct pnp_dev *dev, struct pnp_bios_node * node)
 {
 	struct list_head * pos;
 	struct pnp_dev * pnp_dev;
 	struct pnp_id *dev_id;
 	char id[8];

 	/* check if the device is already added */
 	dev->number = node->handle;
 	list_for_each (pos, &pnpbios_protocol.devices){
 		pnp_dev = list_entry(pos, struct pnp_dev, protocol_list);
 		if (dev->number == pnp_dev->number)
 			return -1;
 	}

 	/* set the initial values for the PnP device */
 	dev_id = kcalloc(1, sizeof(struct pnp_id), GFP_KERNEL);
 	if (!dev_id)
 		return -1;
 	pnpid32_to_pnpid(node->eisa_id,id);
 	memcpy(dev_id->id,id,7);
 	pnp_add_id(dev_id, dev);
 	pnpbios_parse_data_stream(dev, node);
 	dev->active = pnp_is_active(dev);
 	dev->flags = node->flags;
 	if (!(dev->flags & PNPBIOS_NO_CONFIG))
 		dev->capabilities |= PNP_CONFIGURABLE;
 	if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
 		dev->capabilities |= PNP_DISABLE;
 	dev->capabilities |= PNP_READ;
 	if (pnpbios_is_dynamic(dev))
 		dev->capabilities |= PNP_WRITE;
 	if (dev->flags & PNPBIOS_REMOVABLE)
 		dev->capabilities |= PNP_REMOVABLE;
 	dev->protocol = &pnpbios_protocol;

 	/* clear out the damaged flags */
 	if (!dev->active)
 		pnp_init_resource_table(&dev->res);

 	pnp_add_device(dev);
 	pnpbios_interface_attach_device(node);

 	return 0;
 }

 static void __init build_devlist(void)
 {
 	u8 nodenum;
 	unsigned int nodes_got = 0;
 	unsigned int devs = 0;
 	struct pnp_bios_node *node;
 	struct pnp_dev *dev;

 	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
 	if (!node)
 		return;

 	for(nodenum=0; nodenum<0xff; ) {
 		u8 thisnodenum = nodenum;
 		/* eventually we will want to use PNPMODE_STATIC here but for now
 		 * dynamic will help us catch buggy bioses to add to the blacklist.
 		 */
 		if (!pnpbios_dont_use_current_config) {
 			if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node))
 				break;
 		} else {
 			if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_STATIC, node))
 				break;
 		}
 		nodes_got++;
 		dev =  kcalloc(1, sizeof (struct pnp_dev), GFP_KERNEL);
 		if (!dev)
 			break;
 		if(insert_device(dev,node)<0)
 			kfree(dev);
 		else
 			devs++;
 		if (nodenum <= thisnodenum) {
 			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);
 			break;
 		}
 	}
 	kfree(node);

 	printk(KERN_INFO "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
 		nodes_got, nodes_got != 1 ? "s" : "", devs);
 }

 /*
  *
  * INIT AND EXIT
  *
  */

 static int pnpbios_disabled; /* = 0 */
 int pnpbios_dont_use_current_config; /* = 0 */

 #ifndef MODULE
 static int __init pnpbios_setup(char *str)
 {
 	int invert;

 	while ((str != NULL) && (*str != '\0')) {
 		if (strncmp(str, "off", 3) == 0)
 			pnpbios_disabled=1;
 		if (strncmp(str, "on", 2) == 0)
 			pnpbios_disabled=0;
 		invert = (strncmp(str, "no-", 3) == 0);
 		if (invert)
 			str += 3;
 		if (strncmp(str, "curr", 4) == 0)
 			pnpbios_dont_use_current_config = invert;
 		str = strchr(str, ',');
 		if (str != NULL)
 			str += strspn(str, ", \t");
 	}

 	return 1;
 }

 __setup("pnpbios=", pnpbios_setup);
 #endif

 /* PnP BIOS signature: "$PnP" */
 #define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))

 static int __init pnpbios_probe_system(void)
 {
 	union pnp_bios_install_struct *check;
 	u8 sum;
 	int length, i;

 	printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");

 	/*
  	 * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
 	 * structure and, if one is found, sets up the selectors and
 	 * entry points
 	 */
 	for (check = (union pnp_bios_install_struct *) __va(0xf0000);
 	     check < (union pnp_bios_install_struct *) __va(0xffff0);
 	     check = (void *)check + 16) {
 		if (check->fields.signature != PNP_SIGNATURE)
 			continue;
 		printk(KERN_INFO "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n", check);
 		length = check->fields.length;
 		if (!length) {
 			printk(KERN_ERR "PnPBIOS: installation structure is invalid, skipping\n");
 			continue;
 		}
 		for (sum = 0, i = 0; i < length; i++)
 			sum += check->chars[i];
 		if (sum) {
 			printk(KERN_ERR "PnPBIOS: installation structure is corrupted, skipping\n");
 			continue;
 		}
 		if (check->fields.version < 0x10) {
 			printk(KERN_WARNING "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
 			       check->fields.version >> 4,
 			       check->fields.version & 15);
 			continue;
 		}
 		printk(KERN_INFO "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
                        check->fields.version >> 4, check->fields.version & 15,
 		       check->fields.pm16cseg, check->fields.pm16offset,
 		       check->fields.pm16dseg);
 		pnp_bios_install = check;
 		return 1;
 	}

 	printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
 	return 0;
 }

 static int __init exploding_pnp_bios(struct dmi_system_id *d)
 {
 	printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
 	return 0;
 }

 static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
 	{	/* PnPBIOS GPF on boot */
 		.callback = exploding_pnp_bios,
 		.ident = "Higraded P14H",
 		.matches = {
 			DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
 			DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
 			DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
 			DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
 		},
 	},
 	{	/* PnPBIOS GPF on boot */
 		.callback = exploding_pnp_bios,
 		.ident = "ASUS P4P800",
 		.matches = {
 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
 			DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
 		},
 	},
 	{ }
 };

 static int __init pnpbios_init(void)
 {
 	int ret;

 #if defined(CONFIG_PPC_MERGE)
 	if (check_legacy_ioport(PNPBIOS_BASE))
 		return -ENODEV;
 #endif
 	if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table)) {
 		printk(KERN_INFO "PnPBIOS: Disabled\n");
 		return -ENODEV;
 	}

 #ifdef CONFIG_PNPACPI
 	if (!acpi_disabled && !pnpacpi_disabled) {
 		pnpbios_disabled = 1;
 		printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
 		return -ENODEV;
 	}
 #endif /* CONFIG_ACPI */

 	/* scan the system for pnpbios support */
 	if (!pnpbios_probe_system())
 		return -ENODEV;

 	/* make preparations for bios calls */
 	pnpbios_calls_init(pnp_bios_install);

 	/* read the node info */
 	ret = pnp_bios_dev_node_info(&node_info);
 	if (ret) {
 		printk(KERN_ERR "PnPBIOS: Unable to get node info.  Aborting.\n");
 		return ret;
 	}

 	/* register with the pnp layer */
 	ret = pnp_register_protocol(&pnpbios_protocol);
 	if (ret) {
 		printk(KERN_ERR "PnPBIOS: Unable to register driver.  Aborting.\n");
 		return ret;
 	}

 	/* start the proc interface */
 	ret = pnpbios_proc_init();
 	if (ret)
 		printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");

 	/* scan for pnpbios devices */
 	build_devlist();

 	return 0;
 }

 subsys_initcall(pnpbios_init);

 static int __init pnpbios_thread_init(void)
 {
 #if defined(CONFIG_PPC_MERGE)
 	if (check_legacy_ioport(PNPBIOS_BASE))
 		return 0;
 #endif
 	if (pnpbios_disabled)
 		return 0;
 #ifdef CONFIG_HOTPLUG
 	init_completion(&unload_sem);
 	if (kernel_thread(pnp_dock_thread, NULL, CLONE_KERNEL) > 0)
 		unloading = 0;
 #endif
 	return 0;
 }

 #ifndef MODULE

 /* init/main.c calls pnpbios_init early */

 /* Start the kernel thread later: */
 module_init(pnpbios_thread_init);

 #else

 /*
  * N.B.: Building pnpbios as a module hasn't been fully implemented
  */

 MODULE_LICENSE("GPL");

 static int __init pnpbios_init_all(void)
 {
 	int r;

 	r = pnpbios_init();
 	if (r)
 		return r;
 	r = pnpbios_thread_init();
 	if (r)
 		return r;
 	return 0;
 }

 static void __exit pnpbios_exit(void)
 {
 #ifdef CONFIG_HOTPLUG
 	unloading = 1;
 	wait_for_completion(&unload_sem);
 #endif
 	pnpbios_proc_exit();
 	/* We ought to free resources here */
 	return;
 }

 module_init(pnpbios_init_all);
 module_exit(pnpbios_exit);

 #endif

 EXPORT_SYMBOL(pnpbios_protocol);
	/*
	* pnpbios -- PnP BIOS driver
	*
	* This driver provides access to Plug-'n'-Play services provided by
	* the PnP BIOS firmware, described in the following documents:
	* Plug and Play BIOS Specification, Version 1.0A, 5 May 1994
	* Plug and Play BIOS Clarification Paper, 6 October 1994
	* Compaq Computer Corporation, Phoenix Technologies Ltd., Intel Corp.
	*
	* Originally (C) 1998 Christian Schmidt <schmidt@digadd.de>
	* Modifications (C) 1998 Tom Lees <tom@lpsg.demon.co.uk>
	* Minor reorganizations by David Hinds <dahinds@users.sourceforge.net>
	* Further modifications (C) 2001, 2002 by:
	* Alan Cox <alan@redhat.com>
	* Thomas Hood
	* Brian Gerst <bgerst@didntduck.org>
	*
	* Ported to the PnP Layer and several additional improvements (C) 2002
	* by Adam Belay <ambx1@neo.rr.com>
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License as published by the
	* Free Software Foundation; either version 2, or (at your option) any
	* later version.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*/

	/* Change Log
	*
	* Adam Belay - <ambx1@neo.rr.com> - March 16, 2003
	* rev 1.01 Only call pnp_bios_dev_node_info once
	* Added pnpbios_print_status
	* Added several new error messages and info messages
	* Added pnpbios_interface_attach_device
	* integrated core and proc init system
	* Introduced PNPMODE flags
	* Removed some useless includes
	*/

	#include <linux/types.h>
	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/linkage.h>
	#include <linux/kernel.h>
	#include <linux/pnpbios.h>
	#include <linux/device.h>
	#include <linux/pnp.h>
	#include <linux/mm.h>
	#include <linux/smp.h>
	#include <linux/slab.h>
	#include <linux/completion.h>
	#include <linux/spinlock.h>
	#include <linux/dmi.h>
	#include <linux/delay.h>
	#include <linux/acpi.h>

	#include <asm/page.h>
	#include <asm/desc.h>
	#include <asm/system.h>
	#include <asm/byteorder.h>

	#include "pnpbios.h"


	/*
	*
	* PnP BIOS INTERFACE
	*
	*/

	static union pnp_bios_install_struct * pnp_bios_install = NULL;

	int pnp_bios_present(void)
	{
	return (pnp_bios_install != NULL);
	}

	struct pnp_dev_node_info node_info;

	/*
	*
	* DOCKING FUNCTIONS
	*
	*/

	#ifdef CONFIG_HOTPLUG

	static int unloading = 0;
	static struct completion unload_sem;

	/*
	* (Much of this belongs in a shared routine somewhere)
	*/

	static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
	{
	char argv [3], envp, buf, *scratch;
	int i = 0, value;

	if (!current->fs->root) {
	return -EAGAIN;
	}
	if (!(envp = (char *) kcalloc (20, sizeof (char ), GFP_KERNEL))) {
	return -ENOMEM;
	}
	if (!(buf = kcalloc (1, 256, GFP_KERNEL))) {
	kfree (envp);
	return -ENOMEM;
	}

	/* FIXME: if there are actual users of this, it should be integrated into
	* the driver core and use the usual infrastructure like sysfs and uevents */
	argv [0] = "/sbin/pnpbios";
	argv [1] = "dock";
	argv [2] = NULL;

	/* minimal command environment */
	envp [i++] = "HOME=/";
	envp [i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";

	#ifdef DEBUG
	/* hint that policy agent should enter no-stdout debug mode */
	envp [i++] = "DEBUG=kernel";
	#endif
	/* extensible set of named bus-specific parameters,
	* supporting multiple driver selection algorithms.
	*/
	scratch = buf;

	/* action: add, remove */
	envp [i++] = scratch;
	scratch += sprintf (scratch, "ACTION=%s", dock?"add":"remove") + 1;

	/* Report the ident for the dock */
	envp [i++] = scratch;
	scratch += sprintf (scratch, "DOCK=%x/%x/%x",
	info->location_id, info->serial, info->capabilities);
	envp[i] = NULL;

	value = call_usermodehelper (argv [0], argv, envp, 0);
	kfree (buf);
	kfree (envp);
	return 0;
	}

	/*
	* Poll the PnP docking at regular intervals
	*/
	static int pnp_dock_thread(void * unused)
	{
	static struct pnp_docking_station_info now;
	int docked = -1, d = 0;
	daemonize("kpnpbiosd");
	allow_signal(SIGKILL);
	while(!unloading && !signal_pending(current))
	{
	int status;

	/*
	* Poll every 2 seconds
	*/
	msleep_interruptible(2000);

	if(signal_pending(current)) {
	if (try_to_freeze())
	continue;
	break;
	}

	status = pnp_bios_dock_station_info(&now);

	switch(status)
	{
	/*
	* No dock to manage
	*/
	case PNP_FUNCTION_NOT_SUPPORTED:
	complete_and_exit(&unload_sem, 0);
	case PNP_SYSTEM_NOT_DOCKED:
	d = 0;
	break;
	case PNP_SUCCESS:
	d = 1;
	break;
	default:
	pnpbios_print_status( "pnp_dock_thread", status );
	continue;
	}
	if(d != docked)
	{
	if(pnp_dock_event(d, &now)==0)
	{
	docked = d;
	#if 0
	printk(KERN_INFO "PnPBIOS: Docking station %stached\n", docked?"at":"de");
	#endif
	}
	}
	}
	complete_and_exit(&unload_sem, 0);
	}

	#endif /* CONFIG_HOTPLUG */

	static int pnpbios_get_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
	{
	u8 nodenum = dev->number;
	struct pnp_bios_node * node;

	/* just in case */
	if(!pnpbios_is_dynamic(dev))
	return -EPERM;

	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
	if (!node)
	return -1;
	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
	kfree(node);
	return -ENODEV;
	}
	pnpbios_read_resources_from_node(res, node);
	dev->active = pnp_is_active(dev);
	kfree(node);
	return 0;
	}

	static int pnpbios_set_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
	{
	u8 nodenum = dev->number;
	struct pnp_bios_node * node;
	int ret;

	/* just in case */
	if (!pnpbios_is_dynamic(dev))
	return -EPERM;

	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
	if (!node)
	return -1;
	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
	kfree(node);
	return -ENODEV;
	}
	if(pnpbios_write_resources_to_node(res, node)<0) {
	kfree(node);
	return -1;
	}
	ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
	kfree(node);
	if (ret > 0)
	ret = -1;
	return ret;
	}

	static void pnpbios_zero_data_stream(struct pnp_bios_node * node)
	{
	unsigned char * p = (char *)node->data;
	unsigned char * end = (char *)(node->data + node->size);
	unsigned int len;
	int i;
	while ((char )p < (char )end) {
	if(p[0] & 0x80) { /* large tag */
	len = (p[2] << 8) \| p[1];
	p += 3;
	} else {
	if (((p[0]>>3) & 0x0f) == 0x0f)
	return;
	len = p[0] & 0x07;
	p += 1;
	}
	for (i = 0; i < len; i++)
	p[i] = 0;
	p += len;
	}
	printk(KERN_ERR "PnPBIOS: Resource structure did not contain an end tag.\n");
	}

	static int pnpbios_disable_resources(struct pnp_dev *dev)
	{
	struct pnp_bios_node * node;
	u8 nodenum = dev->number;
	int ret;

	/* just in case */
	if(dev->flags & PNPBIOS_NO_DISABLE \|\| !pnpbios_is_dynamic(dev))
	return -EPERM;

	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
	if (!node)
	return -ENOMEM;

	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
	kfree(node);
	return -ENODEV;
	}
	pnpbios_zero_data_stream(node);

	ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
	kfree(node);
	if (ret > 0)
	ret = -1;
	return ret;
	}

	/* PnP Layer support */

	struct pnp_protocol pnpbios_protocol = {
	.name = "Plug and Play BIOS",
	.get = pnpbios_get_resources,
	.set = pnpbios_set_resources,
	.disable = pnpbios_disable_resources,
	};

	static int insert_device(struct pnp_dev dev, struct pnp_bios_node node)
	{
	struct list_head * pos;
	struct pnp_dev * pnp_dev;
	struct pnp_id *dev_id;
	char id[8];

	/* check if the device is already added */
	dev->number = node->handle;
	list_for_each (pos, &pnpbios_protocol.devices){
	pnp_dev = list_entry(pos, struct pnp_dev, protocol_list);
	if (dev->number == pnp_dev->number)
	return -1;
	}

	/* set the initial values for the PnP device */
	dev_id = kcalloc(1, sizeof(struct pnp_id), GFP_KERNEL);
	if (!dev_id)
	return -1;
	pnpid32_to_pnpid(node->eisa_id,id);
	memcpy(dev_id->id,id,7);
	pnp_add_id(dev_id, dev);
	pnpbios_parse_data_stream(dev, node);
	dev->active = pnp_is_active(dev);
	dev->flags = node->flags;
	if (!(dev->flags & PNPBIOS_NO_CONFIG))
	dev->capabilities \|= PNP_CONFIGURABLE;
	if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
	dev->capabilities \|= PNP_DISABLE;
	dev->capabilities \|= PNP_READ;
	if (pnpbios_is_dynamic(dev))
	dev->capabilities \|= PNP_WRITE;
	if (dev->flags & PNPBIOS_REMOVABLE)
	dev->capabilities \|= PNP_REMOVABLE;
	dev->protocol = &pnpbios_protocol;

	/* clear out the damaged flags */
	if (!dev->active)
	pnp_init_resource_table(&dev->res);

	pnp_add_device(dev);
	pnpbios_interface_attach_device(node);

	return 0;
	}

	static void __init build_devlist(void)
	{
	u8 nodenum;
	unsigned int nodes_got = 0;
	unsigned int devs = 0;
	struct pnp_bios_node *node;
	struct pnp_dev *dev;

	node = kcalloc(1, node_info.max_node_size, GFP_KERNEL);
	if (!node)
	return;

	for(nodenum=0; nodenum<0xff; ) {
	u8 thisnodenum = nodenum;
	/* eventually we will want to use PNPMODE_STATIC here but for now
	* dynamic will help us catch buggy bioses to add to the blacklist.
	*/
	if (!pnpbios_dont_use_current_config) {
	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node))
	break;
	} else {
	if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_STATIC, node))
	break;
	}
	nodes_got++;
	dev = kcalloc(1, sizeof (struct pnp_dev), GFP_KERNEL);
	if (!dev)
	break;
	if(insert_device(dev,node)<0)
	kfree(dev);
	else
	devs++;
	if (nodenum <= thisnodenum) {
	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);
	break;
	}
	}
	kfree(node);

	printk(KERN_INFO "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
	nodes_got, nodes_got != 1 ? "s" : "", devs);
	}

	/*
	*
	* INIT AND EXIT
	*
	*/

	static int pnpbios_disabled; /* = 0 */
	int pnpbios_dont_use_current_config; /* = 0 */

	#ifndef MODULE
	static int __init pnpbios_setup(char *str)
	{
	int invert;

	while ((str != NULL) && (*str != '\0')) {
	if (strncmp(str, "off", 3) == 0)
	pnpbios_disabled=1;
	if (strncmp(str, "on", 2) == 0)
	pnpbios_disabled=0;
	invert = (strncmp(str, "no-", 3) == 0);
	if (invert)
	str += 3;
	if (strncmp(str, "curr", 4) == 0)
	pnpbios_dont_use_current_config = invert;
	str = strchr(str, ',');
	if (str != NULL)
	str += strspn(str, ", \t");
	}

	return 1;
	}

	__setup("pnpbios=", pnpbios_setup);
	#endif

	/* PnP BIOS signature: "$PnP" */
	#define PNP_SIGNATURE (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))

	static int __init pnpbios_probe_system(void)
	{
	union pnp_bios_install_struct *check;
	u8 sum;
	int length, i;

	printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");

	/*
	* Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
	* structure and, if one is found, sets up the selectors and
	* entry points
	*/
	for (check = (union pnp_bios_install_struct *) __va(0xf0000);
	check < (union pnp_bios_install_struct *) __va(0xffff0);
	check = (void *)check + 16) {
	if (check->fields.signature != PNP_SIGNATURE)
	continue;
	printk(KERN_INFO "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n", check);
	length = check->fields.length;
	if (!length) {
	printk(KERN_ERR "PnPBIOS: installation structure is invalid, skipping\n");
	continue;
	}
	for (sum = 0, i = 0; i < length; i++)
	sum += check->chars[i];
	if (sum) {
	printk(KERN_ERR "PnPBIOS: installation structure is corrupted, skipping\n");
	continue;
	}
	if (check->fields.version < 0x10) {
	printk(KERN_WARNING "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
	check->fields.version >> 4,
	check->fields.version & 15);
	continue;
	}
	printk(KERN_INFO "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
	check->fields.version >> 4, check->fields.version & 15,
	check->fields.pm16cseg, check->fields.pm16offset,
	check->fields.pm16dseg);
	pnp_bios_install = check;
	return 1;
	}

	printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
	return 0;
	}

	static int __init exploding_pnp_bios(struct dmi_system_id *d)
	{
	printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
	return 0;
	}

	static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
	{ /* PnPBIOS GPF on boot */
	.callback = exploding_pnp_bios,
	.ident = "Higraded P14H",
	.matches = {
	DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
	DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
	DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
	DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
	},
	},
	{ /* PnPBIOS GPF on boot */
	.callback = exploding_pnp_bios,
	.ident = "ASUS P4P800",
	.matches = {
	DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
	DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
	},
	},
	{ }
	};

	static int __init pnpbios_init(void)
	{
	int ret;

	#if defined(CONFIG_PPC_MERGE)
	if (check_legacy_ioport(PNPBIOS_BASE))
	return -ENODEV;
	#endif
	if (pnpbios_disabled \|\| dmi_check_system(pnpbios_dmi_table)) {
	printk(KERN_INFO "PnPBIOS: Disabled\n");
	return -ENODEV;
	}

	#ifdef CONFIG_PNPACPI
	if (!acpi_disabled && !pnpacpi_disabled) {
	pnpbios_disabled = 1;
	printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
	return -ENODEV;
	}
	#endif /* CONFIG_ACPI */

	/* scan the system for pnpbios support */
	if (!pnpbios_probe_system())
	return -ENODEV;

	/* make preparations for bios calls */
	pnpbios_calls_init(pnp_bios_install);

	/* read the node info */
	ret = pnp_bios_dev_node_info(&node_info);
	if (ret) {
	printk(KERN_ERR "PnPBIOS: Unable to get node info. Aborting.\n");
	return ret;
	}

	/* register with the pnp layer */
	ret = pnp_register_protocol(&pnpbios_protocol);
	if (ret) {
	printk(KERN_ERR "PnPBIOS: Unable to register driver. Aborting.\n");
	return ret;
	}

	/* start the proc interface */
	ret = pnpbios_proc_init();
	if (ret)
	printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");

	/* scan for pnpbios devices */
	build_devlist();

	return 0;
	}

	subsys_initcall(pnpbios_init);

	static int __init pnpbios_thread_init(void)
	{
	#if defined(CONFIG_PPC_MERGE)
	if (check_legacy_ioport(PNPBIOS_BASE))
	return 0;
	#endif
	if (pnpbios_disabled)
	return 0;
	#ifdef CONFIG_HOTPLUG
	init_completion(&unload_sem);
	if (kernel_thread(pnp_dock_thread, NULL, CLONE_KERNEL) > 0)
	unloading = 0;
	#endif
	return 0;
	}

	#ifndef MODULE

	/* init/main.c calls pnpbios_init early */

	/* Start the kernel thread later: */
	module_init(pnpbios_thread_init);

	#else

	/*
	* N.B.: Building pnpbios as a module hasn't been fully implemented
	*/

	MODULE_LICENSE("GPL");

	static int __init pnpbios_init_all(void)
	{
	int r;

	r = pnpbios_init();
	if (r)
	return r;
	r = pnpbios_thread_init();
	if (r)
	return r;
	return 0;
	}

	static void __exit pnpbios_exit(void)
	{
	#ifdef CONFIG_HOTPLUG
	unloading = 1;
	wait_for_completion(&unload_sem);
	#endif
	pnpbios_proc_exit();
	/* We ought to free resources here */
	return;
	}

	module_init(pnpbios_init_all);
	module_exit(pnpbios_exit);

	#endif

	EXPORT_SYMBOL(pnpbios_protocol);