Pull sony into release branch

5 files changed, 686 insertions, 0 deletions

diff --git a/Documentation/sony-laptop.txt b/Documentation/sony-laptop.txt
new file mode 100644
index 0000000..dfd26df
--- /dev/null
+++ b/Documentation/sony-laptop.txt
@@ -0,0 +1,106 @@
+Sony Notebook Control Driver (SNC) Readme
+-----------------------------------------
+	Copyright (C) 2004- 2005 Stelian Pop <stelian@popies.net>
+	Copyright (C) 2007 Mattia Dongili <malattia@linux.it>
+
+This mini-driver drives the SNC device present in the ACPI BIOS of
+the Sony Vaio laptops.
+
+It gives access to some extra laptop functionalities. In its current
+form, this driver let the user set or query the screen brightness
+through the backlight subsystem and remove/apply power to some devices.
+
+Backlight control:
+------------------
+If your laptop model supports it, you will find sysfs files in the
+/sys/class/backlight/sony/
+directory. You will be able to query and set the current screen
+brightness:
+	brightness		get/set screen brightness (an iteger
+				between 0 and 7)
+	actual_brightness	reading from this file will query the HW
+				to get real brightness value
+	max_brightness		the maximum brightness value
+
+
+Platform specific:
+------------------
+Loading the sony-laptop module will create a
+/sys/devices/platform/sony-laptop/
+directory populated with some files.
+
+You then read/write integer values from/to those files by using
+standard UNIX tools.
+
+The files are:
+	brightness_default	screen brightness which will be set
+				when the laptop will be rebooted
+	cdpower			power on/off the internal CD drive
+	audiopower		power on/off the internal sound card
+	lanpower		power on/off the internal ethernet card
+				(only in debug mode)
+
+Note that some files may be missing if they are not supported
+by your particular laptop model.
+
+Example usage:
+	# echo "1" > /sys/devices/platform/sony-laptop/brightness_default
+sets the lowest screen brightness for the next and later reboots,
+	# echo "8" > /sys/devices/platform/sony-laptop/brightness_default
+sets the highest screen brightness for the next and later reboots,
+	# cat /sys/devices/platform/sony-laptop/brightness_default
+retrieves the value.
+
+	# echo "0" > /sys/devices/platform/sony-laptop/audiopower
+powers off the sound card,
+	# echo "1" > /sys/devices/platform/sony-laptop/audiopower
+powers on the sound card.
+
+Development:
+------------
+
+If you want to help with the development of this driver (and
+you are not afraid of any side effects doing strange things with
+your ACPI BIOS could have on your laptop), load the driver and
+pass the option 'debug=1'.
+
+REPEAT: DON'T DO THIS IF YOU DON'T LIKE RISKY BUSINESS.
+
+In your kernel logs you will find the list of all ACPI methods
+the SNC device has on your laptop. You can see the GCDP/GCDP methods
+used to pwer on/off the CD drive, but there are others.
+
+I HAVE NO IDEA WHAT THOSE METHODS DO.
+
+The sony-laptop driver creates, for some of those methods (the most
+current ones found on several Vaio models), an entry under
+/sys/devices/platform/sony-laptop, just like the 'cdpower' one.
+You can create other entries corresponding to your own laptop methods by
+further editing the source (see the 'sony_acpi_values' table, and add a new
+entry to this table with your get/set method names using the
+HANDLE_NAMES macro).
+
+Your mission, should you accept it, is to try finding out what
+those entries are for, by reading/writing random values from/to those
+files and find out what is the impact on your laptop.
+
+Should you find anything interesting, please report it back to me,
+I will not disavow all knowledge of your actions :)
+
+Bugs/Limitations:
+-----------------
+
+* This driver is not based on official documentation from Sony
+  (because there is none), so there is no guarantee this driver
+  will work at all, or do the right thing. Although this hasn't
+  happened to me, this driver could do very bad things to your
+  laptop, including permanent damage.
+
+* The sony-laptop and sonypi drivers do not interact at all. In the
+  future, sonypi could use sony-laptop to do (part of) its business.
+
+* spicctrl, which is the userspace tool used to communicate with the
+  sonypi driver (through /dev/sonypi) does not try to use the
+  sony-laptop driver. In the future, spicctrl could try sonypi first,
+  and if it isn't present, try sony-laptop instead.
+
diff --git a/MAINTAINERS b/MAINTAINERS
index 5a546e5..a384551 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3068,6 +3068,8 @@ S:	Maintained
 SONY VAIO CONTROL DEVICE DRIVER
 P:	Stelian Pop
 M:	stelian@popies.net
+P:	Mattia Dongili
+M:	malattia@linux.it
 W:	http://popies.net/sonypi/
 S:	Maintained
 
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index bedae4a..80b199f 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -107,4 +107,19 @@ config MSI_LAPTOP
 
 	  If you have an MSI S270 laptop, say Y or M here.
 
+config SONY_LAPTOP
+	tristate "Sony Laptop Extras"
+	depends on X86 && ACPI
+	select BACKLIGHT_CLASS_DEVICE
+	  ---help---
+	  This mini-driver drives the SNC device present in the ACPI BIOS of
+	  the Sony Vaio laptops.
+
+	  It gives access to some extra laptop functionalities. In its current
+	  form, this driver let the user set or query the screen brightness
+	  through the backlight subsystem and remove/apply power to some
+	  devices.
+
+	  Read <file:Documentation/sony-laptop.txt> for more information.
+
 endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 35da53c..7793ccd 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_LKDTM)		+= lkdtm.o
 obj-$(CONFIG_TIFM_CORE)       	+= tifm_core.o
 obj-$(CONFIG_TIFM_7XX1)       	+= tifm_7xx1.o
 obj-$(CONFIG_SGI_IOC4)		+= ioc4.o
+obj-$(CONFIG_SONY_LAPTOP)	+= sony-laptop.o
diff --git a/drivers/misc/sony-laptop.c b/drivers/misc/sony-laptop.c
new file mode 100644
index 0000000..cabbed0
--- /dev/null
+++ b/drivers/misc/sony-laptop.c
@@ -0,0 +1,562 @@
+/*
+ * ACPI Sony Notebook Control Driver (SNC)
+ *
+ * Copyright (C) 2004-2005 Stelian Pop <stelian@popies.net>
+ * Copyright (C) 2007 Mattia Dongili <malattia@linux.it>
+ *
+ * Parts of this driver inspired from asus_acpi.c and ibm_acpi.c
+ * which are copyrighted by their respective authors.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/backlight.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <acpi/acpi_drivers.h>
+#include <acpi/acpi_bus.h>
+#include <asm/uaccess.h>
+
+#define ACPI_SNC_CLASS		"sony"
+#define ACPI_SNC_HID		"SNY5001"
+#define ACPI_SNC_DRIVER_NAME	"ACPI Sony Notebook Control Driver v0.4"
+
+/* the device uses 1-based values, while the backlight subsystem uses
+   0-based values */
+#define SONY_MAX_BRIGHTNESS	8
+
+#define LOG_PFX			KERN_WARNING "sony-laptop: "
+
+MODULE_AUTHOR("Stelian Pop, Mattia Dongili");
+MODULE_DESCRIPTION(ACPI_SNC_DRIVER_NAME);
+MODULE_LICENSE("GPL");
+
+static int debug;
+module_param(debug, int, 0);
+MODULE_PARM_DESC(debug, "set this to 1 (and RTFM) if you want to help "
+		 "the development of this driver");
+
+static ssize_t sony_acpi_show(struct device *, struct device_attribute *,
+			      char *);
+static ssize_t sony_acpi_store(struct device *, struct device_attribute *,
+			       const char *, size_t);
+static int boolean_validate(const int, const int);
+static int brightness_default_validate(const int, const int);
+
+#define SNC_VALIDATE_IN		0
+#define SNC_VALIDATE_OUT	1
+
+struct sony_acpi_value {
+	char *name;		/* name of the entry */
+	char **acpiget;		/* names of the ACPI get function */
+	char **acpiset;		/* names of the ACPI set function */
+	int (*validate)(const int, const int);	/* input/output validation */
+	int value;		/* current setting */
+	int valid;		/* Has ever been set */
+	int debug;		/* active only in debug mode ? */
+	struct device_attribute devattr;	/* sysfs atribute */
+};
+
+#define HANDLE_NAMES(_name, _values...) \
+	static char *snc_##_name[] = { _values, NULL }
+
+#define SONY_ACPI_VALUE(_name, _getters, _setters, _validate, _debug) \
+	{ \
+		.name		= __stringify(_name), \
+		.acpiget	= _getters, \
+		.acpiset	= _setters, \
+		.validate	= _validate, \
+		.debug		= _debug, \
+		.devattr	= __ATTR(_name, 0, sony_acpi_show, sony_acpi_store), \
+	}
+
+#define SONY_ACPI_VALUE_NULL	{ .name = NULL }
+
+HANDLE_NAMES(fnkey_get, "GHKE");
+
+HANDLE_NAMES(brightness_def_get, "GPBR");
+HANDLE_NAMES(brightness_def_set, "SPBR");
+
+HANDLE_NAMES(cdpower_get, "GCDP");
+HANDLE_NAMES(cdpower_set, "SCDP", "CDPW");
+
+HANDLE_NAMES(audiopower_get, "GAZP");
+HANDLE_NAMES(audiopower_set, "AZPW");
+
+HANDLE_NAMES(lanpower_get, "GLNP");
+HANDLE_NAMES(lanpower_set, "LNPW");
+
+HANDLE_NAMES(PID_get, "GPID");
+
+HANDLE_NAMES(CTR_get, "GCTR");
+HANDLE_NAMES(CTR_set, "SCTR");
+
+HANDLE_NAMES(PCR_get, "GPCR");
+HANDLE_NAMES(PCR_set, "SPCR");
+
+HANDLE_NAMES(CMI_get, "GCMI");
+HANDLE_NAMES(CMI_set, "SCMI");
+
+static struct sony_acpi_value sony_acpi_values[] = {
+	SONY_ACPI_VALUE(brightness_default, snc_brightness_def_get,
+			snc_brightness_def_set, brightness_default_validate, 0),
+	SONY_ACPI_VALUE(fnkey, snc_fnkey_get, NULL, NULL, 0),
+	SONY_ACPI_VALUE(cdpower, snc_cdpower_get, snc_cdpower_set, boolean_validate, 0),
+	SONY_ACPI_VALUE(audiopower, snc_audiopower_get, snc_audiopower_set,
+			boolean_validate, 0),
+	SONY_ACPI_VALUE(lanpower, snc_lanpower_get, snc_lanpower_set,
+			boolean_validate, 1),
+	/* unknown methods */
+	SONY_ACPI_VALUE(PID, snc_PID_get, NULL, NULL, 1),
+	SONY_ACPI_VALUE(CTR, snc_CTR_get, snc_CTR_set, NULL, 1),
+	SONY_ACPI_VALUE(PCR, snc_PCR_get, snc_PCR_set, NULL, 1),
+	SONY_ACPI_VALUE(CMI, snc_CMI_get, snc_CMI_set, NULL, 1),
+	SONY_ACPI_VALUE_NULL
+};
+
+static acpi_handle sony_acpi_handle;
+static struct acpi_device *sony_acpi_acpi_device = NULL;
+
+/*
+ * acpi_evaluate_object wrappers
+ */
+static int acpi_callgetfunc(acpi_handle handle, char *name, int *result)
+{
+	struct acpi_buffer output;
+	union acpi_object out_obj;
+	acpi_status status;
+
+	output.length = sizeof(out_obj);
+	output.pointer = &out_obj;
+
+	status = acpi_evaluate_object(handle, name, NULL, &output);
+	if ((status == AE_OK) && (out_obj.type == ACPI_TYPE_INTEGER)) {
+		*result = out_obj.integer.value;
+		return 0;
+	}
+
+	printk(LOG_PFX "acpi_callreadfunc failed\n");
+
+	return -1;
+}
+
+static int acpi_callsetfunc(acpi_handle handle, char *name, int value,
+			    int *result)
+{
+	struct acpi_object_list params;
+	union acpi_object in_obj;
+	struct acpi_buffer output;
+	union acpi_object out_obj;
+	acpi_status status;
+
+	params.count = 1;
+	params.pointer = &in_obj;
+	in_obj.type = ACPI_TYPE_INTEGER;
+	in_obj.integer.value = value;
+
+	output.length = sizeof(out_obj);
+	output.pointer = &out_obj;
+
+	status = acpi_evaluate_object(handle, name, &params, &output);
+	if (status == AE_OK) {
+		if (result != NULL) {
+			if (out_obj.type != ACPI_TYPE_INTEGER) {
+				printk(LOG_PFX "acpi_evaluate_object bad "
+				       "return type\n");
+				return -1;
+			}
+			*result = out_obj.integer.value;
+		}
+		return 0;
+	}
+
+	printk(LOG_PFX "acpi_evaluate_object failed\n");
+
+	return -1;
+}
+
+/*
+ * sony_acpi_values input/output validate functions
+ */
+
+/* brightness_default_validate:
+ *
+ * manipulate input output values to keep consistency with the
+ * backlight framework for which brightness values are 0-based.
+ */
+static int brightness_default_validate(const int direction, const int value)
+{
+	switch (direction) {
+		case SNC_VALIDATE_OUT:
+			return value - 1;
+		case SNC_VALIDATE_IN:
+			if (value >= 0 && value < SONY_MAX_BRIGHTNESS)
+				return value + 1;
+	}
+	return -EINVAL;
+}
+
+/* boolean_validate:
+ *
+ * on input validate boolean values 0/1, on output just pass the
+ * received value.
+ */
+static int boolean_validate(const int direction, const int value)
+{
+	if (direction == SNC_VALIDATE_IN) {
+		if (value != 0 && value != 1)
+			return -EINVAL;
+	}
+	return value;
+}
+
+/*
+ * Sysfs show/store common to all sony_acpi_values
+ */
+static ssize_t sony_acpi_show(struct device *dev, struct device_attribute *attr,
+			      char *buffer)
+{
+	int value;
+	struct sony_acpi_value *item =
+	    container_of(attr, struct sony_acpi_value, devattr);
+
+	if (!*item->acpiget)
+		return -EIO;
+
+	if (acpi_callgetfunc(sony_acpi_handle, *item->acpiget, &value) < 0)
+		return -EIO;
+
+	if (item->validate)
+		value = item->validate(SNC_VALIDATE_OUT, value);
+
+	return snprintf(buffer, PAGE_SIZE, "%d\n", value);
+}
+
+static ssize_t sony_acpi_store(struct device *dev,
+			       struct device_attribute *attr,
+			       const char *buffer, size_t count)
+{
+	int value;
+	struct sony_acpi_value *item =
+	    container_of(attr, struct sony_acpi_value, devattr);
+
+	if (!item->acpiset)
+		return -EIO;
+
+	if (count > 31)
+		return -EINVAL;
+
+	value = simple_strtoul(buffer, NULL, 10);
+
+	if (item->validate)
+		value = item->validate(SNC_VALIDATE_IN, value);
+
+	if (value < 0)
+		return value;
+
+	if (acpi_callsetfunc(sony_acpi_handle, *item->acpiset, value, NULL) < 0)
+		return -EIO;
+	item->value = value;
+	item->valid = 1;
+	return count;
+}
+
+/*
+ * Platform device
+ */
+static struct platform_driver sncpf_driver = {
+	.driver = {
+		   .name = "sony-laptop",
+		   .owner = THIS_MODULE,
+		   }
+};
+static struct platform_device *sncpf_device;
+
+static int sony_snc_pf_add(void)
+{
+	acpi_handle handle;
+	struct sony_acpi_value *item;
+	int ret = 0;
+
+	ret = platform_driver_register(&sncpf_driver);
+	if (ret)
+		goto out;
+
+	sncpf_device = platform_device_alloc("sony-laptop", -1);
+	if (!sncpf_device) {
+		ret = -ENOMEM;
+		goto out_platform_registered;
+	}
+
+	ret = platform_device_add(sncpf_device);
+	if (ret)
+		goto out_platform_alloced;
+
+	for (item = sony_acpi_values; item->name; ++item) {
+
+		if (!debug && item->debug)
+			continue;
+
+		/* find the available acpiget as described in the DSDT */
+		for (; item->acpiget && *item->acpiget; ++item->acpiget) {
+			if (ACPI_SUCCESS(acpi_get_handle(sony_acpi_handle,
+							 *item->acpiget,
+							 &handle))) {
+				if (debug)
+					printk(LOG_PFX "Found %s getter: %s\n",
+					       item->name, *item->acpiget);
+				item->devattr.attr.mode |= S_IRUGO;
+				break;
+			}
+		}
+
+		/* find the available acpiset as described in the DSDT */
+		for (; item->acpiset && *item->acpiset; ++item->acpiset) {
+			if (ACPI_SUCCESS(acpi_get_handle(sony_acpi_handle,
+							 *item->acpiset,
+							 &handle))) {
+				if (debug)
+					printk(LOG_PFX "Found %s setter: %s\n",
+					       item->name, *item->acpiset);
+				item->devattr.attr.mode |= S_IWUSR;
+				break;
+			}
+		}
+
+		if (item->devattr.attr.mode != 0) {
+			ret =
+			    device_create_file(&sncpf_device->dev,
+					       &item->devattr);
+			if (ret)
+				goto out_sysfs;
+		}
+	}
+
+	return 0;
+
+      out_sysfs:
+	for (item = sony_acpi_values; item->name; ++item) {
+		device_remove_file(&sncpf_device->dev, &item->devattr);
+	}
+	platform_device_del(sncpf_device);
+      out_platform_alloced:
+	platform_device_put(sncpf_device);
+      out_platform_registered:
+	platform_driver_unregister(&sncpf_driver);
+      out:
+	return ret;
+}
+
+static void sony_snc_pf_remove(void)
+{
+	struct sony_acpi_value *item;
+
+	for (item = sony_acpi_values; item->name; ++item) {
+		device_remove_file(&sncpf_device->dev, &item->devattr);
+	}
+
+	platform_device_del(sncpf_device);
+	platform_device_put(sncpf_device);
+	platform_driver_unregister(&sncpf_driver);
+}
+
+/*
+ * Backlight device
+ */
+static int sony_backlight_update_status(struct backlight_device *bd)
+{
+	return acpi_callsetfunc(sony_acpi_handle, "SBRT",
+				bd->props->brightness + 1, NULL);
+}
+
+static int sony_backlight_get_brightness(struct backlight_device *bd)
+{
+	int value;
+
+	if (acpi_callgetfunc(sony_acpi_handle, "GBRT", &value))
+		return 0;
+	/* brightness levels are 1-based, while backlight ones are 0-based */
+	return value - 1;
+}
+
+static struct backlight_device *sony_backlight_device;
+static struct backlight_properties sony_backlight_properties = {
+	.owner = THIS_MODULE,
+	.update_status = sony_backlight_update_status,
+	.get_brightness = sony_backlight_get_brightness,
+	.max_brightness = SONY_MAX_BRIGHTNESS - 1,
+};
+
+/*
+ * ACPI callbacks
+ */
+static void sony_acpi_notify(acpi_handle handle, u32 event, void *data)
+{
+	if (debug)
+		printk(LOG_PFX "sony_acpi_notify, event: %d\n", event);
+	acpi_bus_generate_event(sony_acpi_acpi_device, 1, event);
+}
+
+static acpi_status sony_walk_callback(acpi_handle handle, u32 level,
+				      void *context, void **return_value)
+{
+	struct acpi_namespace_node *node;
+	union acpi_operand_object *operand;
+
+	node = (struct acpi_namespace_node *)handle;
+	operand = (union acpi_operand_object *)node->object;
+
+	printk(LOG_PFX "method: name: %4.4s, args %X\n", node->name.ascii,
+	       (u32) operand->method.param_count);
+
+	return AE_OK;
+}
+
+/*
+ * ACPI device
+ */
+static int sony_acpi_resume(struct acpi_device *device)
+{
+	struct sony_acpi_value *item;
+
+	for (item = sony_acpi_values; item->name; item++) {
+		int ret;
+
+		if (!item->valid)
+			continue;
+		ret = acpi_callsetfunc(sony_acpi_handle, *item->acpiset,
+				       item->value, NULL);
+		if (ret < 0) {
+			printk("%s: %d\n", __FUNCTION__, ret);
+			break;
+		}
+	}
+	return 0;
+}
+
+static int sony_acpi_add(struct acpi_device *device)
+{
+	acpi_status status;
+	int result;
+	acpi_handle handle;
+
+	sony_acpi_acpi_device = device;
+
+	sony_acpi_handle = device->handle;
+
+	if (debug) {
+		status = acpi_walk_namespace(ACPI_TYPE_METHOD, sony_acpi_handle,
+					     1, sony_walk_callback, NULL, NULL);
+		if (ACPI_FAILURE(status)) {
+			printk(LOG_PFX "unable to walk acpi resources\n");
+			result = -ENODEV;
+			goto outwalk;
+		}
+	}
+
+	status = acpi_install_notify_handler(sony_acpi_handle,
+					     ACPI_DEVICE_NOTIFY,
+					     sony_acpi_notify, NULL);
+	if (ACPI_FAILURE(status)) {
+		printk(LOG_PFX "unable to install notify handler\n");
+		result = -ENODEV;
+		goto outwalk;
+	}
+
+	if (ACPI_SUCCESS(acpi_get_handle(sony_acpi_handle, "GBRT", &handle))) {
+		sony_backlight_device = backlight_device_register("sony", NULL,
+								  NULL,
+								  &sony_backlight_properties);
+
+		if (IS_ERR(sony_backlight_device)) {
+			printk(LOG_PFX "unable to register backlight device\n");
+			sony_backlight_device = NULL;
+		} else
+			sony_backlight_properties.brightness =
+			    sony_backlight_get_brightness
+			    (sony_backlight_device);
+	}
+
+	if (sony_snc_pf_add())
+		goto outbacklight;
+
+	printk(KERN_INFO ACPI_SNC_DRIVER_NAME " successfully installed\n");
+
+	return 0;
+
+      outbacklight:
+	if (sony_backlight_device)
+		backlight_device_unregister(sony_backlight_device);
+
+	status = acpi_remove_notify_handler(sony_acpi_handle,
+					    ACPI_DEVICE_NOTIFY,
+					    sony_acpi_notify);
+	if (ACPI_FAILURE(status))
+		printk(LOG_PFX "unable to remove notify handler\n");
+      outwalk:
+	return result;
+}
+
+static int sony_acpi_remove(struct acpi_device *device, int type)
+{
+	acpi_status status;
+
+	if (sony_backlight_device)
+		backlight_device_unregister(sony_backlight_device);
+
+	sony_acpi_acpi_device = NULL;
+
+	status = acpi_remove_notify_handler(sony_acpi_handle,
+					    ACPI_DEVICE_NOTIFY,
+					    sony_acpi_notify);
+	if (ACPI_FAILURE(status))
+		printk(LOG_PFX "unable to remove notify handler\n");
+
+	sony_snc_pf_remove();
+
+	printk(KERN_INFO ACPI_SNC_DRIVER_NAME " successfully removed\n");
+
+	return 0;
+}
+
+static struct acpi_driver sony_acpi_driver = {
+	.name = ACPI_SNC_DRIVER_NAME,
+	.class = ACPI_SNC_CLASS,
+	.ids = ACPI_SNC_HID,
+	.ops = {
+		.add = sony_acpi_add,
+		.remove = sony_acpi_remove,
+		.resume = sony_acpi_resume,
+		},
+};
+
+static int __init sony_acpi_init(void)
+{
+	return acpi_bus_register_driver(&sony_acpi_driver);
+}
+
+static void __exit sony_acpi_exit(void)
+{
+	acpi_bus_unregister_driver(&sony_acpi_driver);
+}
+
+module_init(sony_acpi_init);
+module_exit(sony_acpi_exit);