1 files changed, 775 insertions, 0 deletions

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
new file mode 100644
index 000000000000..4edff1738579
--- /dev/null
+++ b/drivers/acpi/bus.c
@@ -0,0 +1,775 @@
+/*
+ *  acpi_bus.c - ACPI Bus Driver ($Revision: 80 $)
+ *
+ *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.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 of the License, 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.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/list.h>
+#include <linux/sched.h>
+#include <linux/pm.h>
+#include <linux/device.h>
+#include <linux/proc_fs.h>
+#ifdef CONFIG_X86
+#include <asm/mpspec.h>
+#endif
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+
+
+#define _COMPONENT		ACPI_BUS_COMPONENT
+ACPI_MODULE_NAME		("acpi_bus")
+
+#ifdef	CONFIG_X86
+extern void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger);
+#endif
+
+FADT_DESCRIPTOR			acpi_fadt;
+EXPORT_SYMBOL(acpi_fadt);
+
+struct acpi_device		*acpi_root;
+struct proc_dir_entry		*acpi_root_dir;
+EXPORT_SYMBOL(acpi_root_dir);
+
+#define STRUCT_TO_INT(s)	(*((int*)&s))
+
+/* --------------------------------------------------------------------------
+                                Device Management
+   -------------------------------------------------------------------------- */
+
+int
+acpi_bus_get_device (
+	acpi_handle		handle,
+	struct acpi_device	**device)
+{
+	acpi_status		status = AE_OK;
+
+	ACPI_FUNCTION_TRACE("acpi_bus_get_device");
+
+	if (!device)
+		return_VALUE(-EINVAL);
+
+	/* TBD: Support fixed-feature devices */
+
+	status = acpi_get_data(handle, acpi_bus_data_handler, (void**) device);
+	if (ACPI_FAILURE(status) || !*device) {
+		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "No context for object [%p]\n",
+			handle));
+		return_VALUE(-ENODEV);
+	}
+
+	return_VALUE(0);
+}
+EXPORT_SYMBOL(acpi_bus_get_device);
+
+int
+acpi_bus_get_status (
+	struct acpi_device	*device)
+{
+	acpi_status		status = AE_OK;
+	unsigned long		sta = 0;
+	
+	ACPI_FUNCTION_TRACE("acpi_bus_get_status");
+
+	if (!device)
+		return_VALUE(-EINVAL);
+
+	/*
+	 * Evaluate _STA if present.
+	 */
+	if (device->flags.dynamic_status) {
+		status = acpi_evaluate_integer(device->handle, "_STA", NULL, &sta);
+		if (ACPI_FAILURE(status))
+			return_VALUE(-ENODEV);
+		STRUCT_TO_INT(device->status) = (int) sta;
+	}
+
+	/*
+	 * Otherwise we assume the status of our parent (unless we don't
+	 * have one, in which case status is implied).
+	 */
+	else if (device->parent)
+		device->status = device->parent->status;
+	else
+		STRUCT_TO_INT(device->status) = 0x0F;
+
+	if (device->status.functional && !device->status.present) {
+		printk(KERN_WARNING PREFIX "Device [%s] status [%08x]: "
+			"functional but not present; setting present\n",
+			device->pnp.bus_id,
+			(u32) STRUCT_TO_INT(device->status));
+		device->status.present = 1;
+	}
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] status [%08x]\n", 
+		device->pnp.bus_id, (u32) STRUCT_TO_INT(device->status)));
+
+	return_VALUE(0);
+}
+EXPORT_SYMBOL(acpi_bus_get_status);
+
+
+/* --------------------------------------------------------------------------
+                                 Power Management
+   -------------------------------------------------------------------------- */
+
+int
+acpi_bus_get_power (
+	acpi_handle		handle,
+	int			*state)
+{
+	int			result = 0;
+	acpi_status             status = 0;
+	struct acpi_device	*device = NULL;
+	unsigned long		psc = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_bus_get_power");
+
+	result = acpi_bus_get_device(handle, &device);
+	if (result)
+		return_VALUE(result);
+
+	*state = ACPI_STATE_UNKNOWN;
+
+	if (!device->flags.power_manageable) {
+		/* TBD: Non-recursive algorithm for walking up hierarchy */
+		if (device->parent)
+			*state = device->parent->power.state;
+		else
+			*state = ACPI_STATE_D0;
+	}
+	else {
+		/*
+		 * Get the device's power state either directly (via _PSC) or 
+		 * indirectly (via power resources).
+		 */
+		if (device->power.flags.explicit_get) {
+			status = acpi_evaluate_integer(device->handle, "_PSC", 
+				NULL, &psc);
+			if (ACPI_FAILURE(status))
+				return_VALUE(-ENODEV);
+			device->power.state = (int) psc;
+		}
+		else if (device->power.flags.power_resources) {
+			result = acpi_power_get_inferred_state(device);
+			if (result)
+				return_VALUE(result);
+		}
+
+		*state = device->power.state;
+	}
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
+		device->pnp.bus_id, device->power.state));
+
+	return_VALUE(0);
+}
+EXPORT_SYMBOL(acpi_bus_get_power);
+
+
+int
+acpi_bus_set_power (
+	acpi_handle		handle,
+	int			state)
+{
+	int			result = 0;
+	acpi_status		status = AE_OK;
+	struct acpi_device	*device = NULL;
+	char			object_name[5] = {'_','P','S','0'+state,'\0'};
+
+	ACPI_FUNCTION_TRACE("acpi_bus_set_power");
+
+	result = acpi_bus_get_device(handle, &device);
+	if (result)
+		return_VALUE(result);
+
+	if ((state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
+		return_VALUE(-EINVAL);
+
+	/* Make sure this is a valid target state */
+
+	if (!device->flags.power_manageable) {
+		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Device is not power manageable\n"));
+		return_VALUE(-ENODEV);
+	}
+	if (state == device->power.state) {
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n", state));
+		return_VALUE(0);
+	}
+	if (!device->power.states[state].flags.valid) {
+		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Device does not support D%d\n", state));
+		return_VALUE(-ENODEV);
+	}
+	if (device->parent && (state < device->parent->power.state)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Cannot set device to a higher-powered state than parent\n"));
+		return_VALUE(-ENODEV);
+	}
+
+	/*
+	 * Transition Power
+	 * ----------------
+	 * On transitions to a high-powered state we first apply power (via
+	 * power resources) then evalute _PSx.  Conversly for transitions to
+	 * a lower-powered state.
+	 */ 
+	if (state < device->power.state) {
+		if (device->power.flags.power_resources) {
+			result = acpi_power_transition(device, state);
+			if (result)
+				goto end;
+		}
+		if (device->power.states[state].flags.explicit_set) {
+			status = acpi_evaluate_object(device->handle, 
+				object_name, NULL, NULL);
+			if (ACPI_FAILURE(status)) {
+				result = -ENODEV;
+				goto end;
+			}
+		}
+	}
+	else {
+		if (device->power.states[state].flags.explicit_set) {
+			status = acpi_evaluate_object(device->handle, 
+				object_name, NULL, NULL);
+			if (ACPI_FAILURE(status)) {
+				result = -ENODEV;
+				goto end;
+			}
+		}
+		if (device->power.flags.power_resources) {
+			result = acpi_power_transition(device, state);
+			if (result)
+				goto end;
+		}
+	}
+
+end:
+	if (result)
+		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Error transitioning device [%s] to D%d\n",
+			device->pnp.bus_id, state));
+	else
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] transitioned to D%d\n",
+			device->pnp.bus_id, state));
+
+	return_VALUE(result);
+}
+EXPORT_SYMBOL(acpi_bus_set_power);
+
+
+
+/* --------------------------------------------------------------------------
+                                Event Management
+   -------------------------------------------------------------------------- */
+
+static DEFINE_SPINLOCK(acpi_bus_event_lock);
+
+LIST_HEAD(acpi_bus_event_list);
+DECLARE_WAIT_QUEUE_HEAD(acpi_bus_event_queue);
+
+extern int			event_is_open;
+
+int
+acpi_bus_generate_event (
+	struct acpi_device	*device,
+	u8			type,
+	int			data)
+{
+	struct acpi_bus_event	*event = NULL;
+	unsigned long		flags = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_bus_generate_event");
+
+	if (!device)
+		return_VALUE(-EINVAL);
+
+	/* drop event on the floor if no one's listening */
+	if (!event_is_open)
+		return_VALUE(0);
+
+	event = kmalloc(sizeof(struct acpi_bus_event), GFP_ATOMIC);
+	if (!event)
+		return_VALUE(-ENOMEM);
+
+	strcpy(event->device_class, device->pnp.device_class);
+	strcpy(event->bus_id, device->pnp.bus_id);
+	event->type = type;
+	event->data = data;
+
+	spin_lock_irqsave(&acpi_bus_event_lock, flags);
+	list_add_tail(&event->node, &acpi_bus_event_list);
+	spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
+
+	wake_up_interruptible(&acpi_bus_event_queue);
+
+	return_VALUE(0);
+}
+EXPORT_SYMBOL(acpi_bus_generate_event);
+
+int
+acpi_bus_receive_event (
+	struct acpi_bus_event	*event)
+{
+	unsigned long		flags = 0;
+	struct acpi_bus_event	*entry = NULL;
+
+	DECLARE_WAITQUEUE(wait, current);
+
+	ACPI_FUNCTION_TRACE("acpi_bus_receive_event");
+
+	if (!event)
+		return_VALUE(-EINVAL);
+
+	if (list_empty(&acpi_bus_event_list)) {
+
+		set_current_state(TASK_INTERRUPTIBLE);
+		add_wait_queue(&acpi_bus_event_queue, &wait);
+
+		if (list_empty(&acpi_bus_event_list))
+			schedule();
+
+		remove_wait_queue(&acpi_bus_event_queue, &wait);
+		set_current_state(TASK_RUNNING);
+
+		if (signal_pending(current))
+			return_VALUE(-ERESTARTSYS);
+	}
+
+	spin_lock_irqsave(&acpi_bus_event_lock, flags);
+	entry = list_entry(acpi_bus_event_list.next, struct acpi_bus_event, node);
+	if (entry)
+		list_del(&entry->node);
+	spin_unlock_irqrestore(&acpi_bus_event_lock, flags);
+
+	if (!entry)
+		return_VALUE(-ENODEV);
+
+	memcpy(event, entry, sizeof(struct acpi_bus_event));
+
+	kfree(entry);
+
+	return_VALUE(0);
+}
+EXPORT_SYMBOL(acpi_bus_receive_event);
+
+
+/* --------------------------------------------------------------------------
+                             Notification Handling
+   -------------------------------------------------------------------------- */
+
+static int
+acpi_bus_check_device (
+	struct acpi_device	*device,
+	int			*status_changed)
+{
+	acpi_status             status = 0;
+	struct acpi_device_status old_status;
+
+	ACPI_FUNCTION_TRACE("acpi_bus_check_device");
+
+	if (!device)
+		return_VALUE(-EINVAL);
+
+	if (status_changed)
+		*status_changed = 0;
+
+	old_status = device->status;
+
+	/*
+	 * Make sure this device's parent is present before we go about
+	 * messing with the device.
+	 */
+	if (device->parent && !device->parent->status.present) {
+		device->status = device->parent->status;
+		if (STRUCT_TO_INT(old_status) != STRUCT_TO_INT(device->status)) {
+			if (status_changed)
+				*status_changed = 1;
+		}
+		return_VALUE(0);
+	}
+
+	status = acpi_bus_get_status(device);
+	if (ACPI_FAILURE(status))
+		return_VALUE(-ENODEV);
+
+	if (STRUCT_TO_INT(old_status) == STRUCT_TO_INT(device->status))
+		return_VALUE(0);
+
+	if (status_changed)
+		*status_changed = 1;
+	
+	/*
+	 * Device Insertion/Removal
+	 */
+	if ((device->status.present) && !(old_status.present)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
+		/* TBD: Handle device insertion */
+	}
+	else if (!(device->status.present) && (old_status.present)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device removal detected\n"));
+		/* TBD: Handle device removal */
+	}
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_bus_check_scope (
+	struct acpi_device	*device)
+{
+	int			result = 0;
+	int			status_changed = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_bus_check_scope");
+
+	if (!device)
+		return_VALUE(-EINVAL);
+
+	/* Status Change? */
+	result = acpi_bus_check_device(device, &status_changed);
+	if (result)
+		return_VALUE(result);
+
+	if (!status_changed)
+		return_VALUE(0);
+
+	/*
+	 * TBD: Enumerate child devices within this device's scope and
+	 *       run acpi_bus_check_device()'s on them.
+	 */
+
+	return_VALUE(0);
+}
+
+
+/**
+ * acpi_bus_notify
+ * ---------------
+ * Callback for all 'system-level' device notifications (values 0x00-0x7F).
+ */
+static void 
+acpi_bus_notify (
+	acpi_handle             handle,
+	u32                     type,
+	void                    *data)
+{
+	int			result = 0;
+	struct acpi_device	*device = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_bus_notify");
+
+	if (acpi_bus_get_device(handle, &device))
+		return_VOID;
+
+	switch (type) {
+
+	case ACPI_NOTIFY_BUS_CHECK:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Received BUS CHECK notification for device [%s]\n", 
+			device->pnp.bus_id));
+		result = acpi_bus_check_scope(device);
+		/* 
+		 * TBD: We'll need to outsource certain events to non-ACPI
+		 *	drivers via the device manager (device.c).
+		 */
+		break;
+
+	case ACPI_NOTIFY_DEVICE_CHECK:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Received DEVICE CHECK notification for device [%s]\n", 
+			device->pnp.bus_id));
+		result = acpi_bus_check_device(device, NULL);
+		/* 
+		 * TBD: We'll need to outsource certain events to non-ACPI
+		 *	drivers via the device manager (device.c).
+		 */
+		break;
+
+	case ACPI_NOTIFY_DEVICE_WAKE:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Received DEVICE WAKE notification for device [%s]\n", 
+			device->pnp.bus_id));
+		/* TBD */
+		break;
+
+	case ACPI_NOTIFY_EJECT_REQUEST:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Received EJECT REQUEST notification for device [%s]\n", 
+			device->pnp.bus_id));
+		/* TBD */
+		break;
+
+	case ACPI_NOTIFY_DEVICE_CHECK_LIGHT:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Received DEVICE CHECK LIGHT notification for device [%s]\n", 
+			device->pnp.bus_id));
+		/* TBD: Exactly what does 'light' mean? */
+		break;
+
+	case ACPI_NOTIFY_FREQUENCY_MISMATCH:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Received FREQUENCY MISMATCH notification for device [%s]\n", 
+			device->pnp.bus_id));
+		/* TBD */
+		break;
+
+	case ACPI_NOTIFY_BUS_MODE_MISMATCH:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Received BUS MODE MISMATCH notification for device [%s]\n", 
+			device->pnp.bus_id));
+		/* TBD */
+		break;
+
+	case ACPI_NOTIFY_POWER_FAULT:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Received POWER FAULT notification for device [%s]\n", 
+			device->pnp.bus_id));
+		/* TBD */
+		break;
+
+	default:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Received unknown/unsupported notification [%08x]\n", 
+			type));
+		break;
+	}
+
+	return_VOID;
+}
+
+/* --------------------------------------------------------------------------
+                             Initialization/Cleanup
+   -------------------------------------------------------------------------- */
+
+static int __init
+acpi_bus_init_irq (void)
+{
+	acpi_status		status = AE_OK;
+	union acpi_object	arg = {ACPI_TYPE_INTEGER};
+	struct acpi_object_list	arg_list = {1, &arg};
+	char			*message = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_bus_init_irq");
+
+	/* 
+	 * Let the system know what interrupt model we are using by
+	 * evaluating the \_PIC object, if exists.
+	 */
+
+	switch (acpi_irq_model) {
+	case ACPI_IRQ_MODEL_PIC:
+		message = "PIC";
+		break;
+	case ACPI_IRQ_MODEL_IOAPIC:
+		message = "IOAPIC";
+		break;
+	case ACPI_IRQ_MODEL_IOSAPIC:
+		message = "IOSAPIC";
+		break;
+	default:
+		printk(KERN_WARNING PREFIX "Unknown interrupt routing model\n");
+		return_VALUE(-ENODEV);
+	}
+
+	printk(KERN_INFO PREFIX "Using %s for interrupt routing\n", message);
+
+	arg.integer.value = acpi_irq_model;
+
+	status = acpi_evaluate_object(NULL, "\\_PIC", &arg_list, NULL);
+	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PIC\n"));
+		return_VALUE(-ENODEV);
+	}
+
+	return_VALUE(0);
+}
+
+
+void __init
+acpi_early_init (void)
+{
+	acpi_status		status = AE_OK;
+	struct acpi_buffer	buffer = {sizeof(acpi_fadt), &acpi_fadt};
+
+	ACPI_FUNCTION_TRACE("acpi_early_init");
+
+	if (acpi_disabled)
+		return_VOID;
+
+	/* enable workarounds, unless strict ACPI spec. compliance */
+	if (!acpi_strict)
+		acpi_gbl_enable_interpreter_slack = TRUE;
+
+	status = acpi_initialize_subsystem();
+	if (ACPI_FAILURE(status)) {
+		printk(KERN_ERR PREFIX "Unable to initialize the ACPI Interpreter\n");
+		goto error0;
+	}
+
+	status = acpi_load_tables();
+	if (ACPI_FAILURE(status)) {
+		printk(KERN_ERR PREFIX "Unable to load the System Description Tables\n");
+		goto error0;
+	}
+
+	/*
+	 * Get a separate copy of the FADT for use by other drivers.
+	 */
+	status = acpi_get_table(ACPI_TABLE_FADT, 1, &buffer);
+	if (ACPI_FAILURE(status)) {
+		printk(KERN_ERR PREFIX "Unable to get the FADT\n");
+		goto error0;
+	}
+
+#ifdef CONFIG_X86
+	if (!acpi_ioapic) {
+		extern acpi_interrupt_flags acpi_sci_flags;
+
+		/* compatible (0) means level (3) */
+		if (acpi_sci_flags.trigger == 0)
+			acpi_sci_flags.trigger = 3;
+
+		/* Set PIC-mode SCI trigger type */
+		acpi_pic_sci_set_trigger(acpi_fadt.sci_int, acpi_sci_flags.trigger);
+	} else {
+		extern int acpi_sci_override_gsi;
+		/*
+		 * now that acpi_fadt is initialized,
+		 * update it with result from INT_SRC_OVR parsing
+		 */
+		acpi_fadt.sci_int = acpi_sci_override_gsi;
+	}
+#endif
+
+	status = acpi_enable_subsystem(~(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE));
+	if (ACPI_FAILURE(status)) {
+		printk(KERN_ERR PREFIX "Unable to enable ACPI\n");
+		goto error0;
+	}
+
+	return_VOID;
+
+error0:
+	disable_acpi();
+	return_VOID;
+}
+
+static int __init
+acpi_bus_init (void)
+{
+	int			result = 0;
+	acpi_status		status = AE_OK;
+	extern acpi_status	acpi_os_initialize1(void);
+
+	ACPI_FUNCTION_TRACE("acpi_bus_init");
+
+	status = acpi_os_initialize1();
+
+	status = acpi_enable_subsystem(ACPI_NO_HARDWARE_INIT | ACPI_NO_ACPI_ENABLE);
+	if (ACPI_FAILURE(status)) {
+		printk(KERN_ERR PREFIX "Unable to start the ACPI Interpreter\n");
+		goto error1;
+	}
+
+	if (ACPI_FAILURE(status)) {
+		printk(KERN_ERR PREFIX "Unable to initialize ACPI OS objects\n");
+		goto error1;
+	}
+#ifdef CONFIG_ACPI_EC
+	/*
+	 * ACPI 2.0 requires the EC driver to be loaded and work before
+	 * the EC device is found in the namespace (i.e. before acpi_initialize_objects()
+	 * is called).
+	 *
+	 * This is accomplished by looking for the ECDT table, and getting 
+	 * the EC parameters out of that.
+	 */
+	status = acpi_ec_ecdt_probe();
+	/* Ignore result. Not having an ECDT is not fatal. */
+#endif
+
+	status = acpi_initialize_objects(ACPI_FULL_INITIALIZATION);
+	if (ACPI_FAILURE(status)) {
+		printk(KERN_ERR PREFIX "Unable to initialize ACPI objects\n");
+		goto error1;
+	}
+
+	printk(KERN_INFO PREFIX "Interpreter enabled\n");
+
+	/*
+	 * Get the system interrupt model and evaluate \_PIC.
+	 */
+	result = acpi_bus_init_irq();
+	if (result)
+		goto error1;
+
+	/*
+	 * Register the for all standard device notifications.
+	 */
+	status = acpi_install_notify_handler(ACPI_ROOT_OBJECT, ACPI_SYSTEM_NOTIFY, &acpi_bus_notify, NULL);
+	if (ACPI_FAILURE(status)) {
+		printk(KERN_ERR PREFIX "Unable to register for device notifications\n");
+		goto error1;
+	}
+
+	/*
+	 * Create the top ACPI proc directory
+	 */
+	acpi_root_dir = proc_mkdir(ACPI_BUS_FILE_ROOT, NULL);
+
+	return_VALUE(0);
+
+	/* Mimic structured exception handling */
+error1:
+	acpi_terminate();
+	return_VALUE(-ENODEV);
+}
+
+decl_subsys(acpi,NULL,NULL);
+
+static int __init acpi_init (void)
+{
+	int			result = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_init");
+
+	printk(KERN_INFO PREFIX "Subsystem revision %08x\n",
+		ACPI_CA_VERSION);
+
+	if (acpi_disabled) {
+		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
+		return_VALUE(-ENODEV);
+	}
+
+	firmware_register(&acpi_subsys);
+
+	result = acpi_bus_init();
+
+	if (!result) {
+#ifdef CONFIG_PM
+		if (!PM_IS_ACTIVE())
+			pm_active = 1;
+		else {
+			printk(KERN_INFO PREFIX "APM is already active, exiting\n");
+			disable_acpi();
+			result = -ENODEV;
+		}
+#endif
+	} else
+		disable_acpi();
+
+	return_VALUE(result);
+}
+
+subsys_initcall(acpi_init);