Re: [PATCH 0/5] I8K driver facelift

[Dmitry Torokhov <dtor_core@ameritech.net>]

[-- Attachment #1: Type: text/plain, Size: 1043 bytes --]

Hi,

On Thursday 17 March 2005 04:46, Frank Sorenson wrote:
> Dmitry Torokhov wrote:
> | Hrm, can we be a little more explicit and not poke in the sysfs guts right
> | in the driver? What do you think about the patch below athat implements
> | "attribute arrays"? And I am attaching cumulative i8k patch using these
> | arrays so they can be tested.
> 
> Also, with power_status being a module parameter defaulting to 0/off, we
> can leave out the device_create_file for the i8k_power_status_attr.  No
> need to expose it in sysfs if it will always return -EIO.
>

Since root can toggle power_status through sysfs at runtime (see
/sys/modules/i8k/parameters/power_status) I think it is simplier to have
the file always created. 

I have implemented arrays of groups of attributes:

[dtor@core ~]$ ls -R /sys/bus/platform/devices/i8k/fan/
/sys/bus/platform/devices/i8k/fan/:
0  1

/sys/bus/platform/devices/i8k/fan/0:
speed  state

/sys/bus/platform/devices/i8k/fan/1:
speed  state

Please give it a try when you have time. Thanks!

-- 
Dmitry

[-- Attachment #2: attr-array.patch --]
[-- Type: text/x-diff, Size: 6439 bytes --]

===================================================================

sysfs: add support for attribute arrays so it is possible to create
       a number of similar attributes all sharing the same show and
       store handlers:

          ../<attr_name>/0
          ../<attr_name>/1
               ...
          ../<attr_name>/<n>

       Number of attributes can be specified at run-time.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>


 fs/sysfs/Makefile     |    2 
 fs/sysfs/array.c      |  162 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/sysfs.h |   20 +++++-
 3 files changed, 182 insertions(+), 2 deletions(-)

Index: dtor/fs/sysfs/array.c
===================================================================
--- /dev/null
+++ dtor/fs/sysfs/array.c
@@ -0,0 +1,162 @@
+/*
+ * fs/sysfs/array.c - Operations for adding/removing arrays of attributes.
+ *
+ * Copyright (c) 2005 Dmitry Torokhov <dtor@mail.ru>
+ *
+ * This file is released under the GPL v2.
+ *
+ */
+
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/dcache.h>
+#include "sysfs.h"
+
+struct attr_element {
+	struct attribute attr;
+	unsigned int idx;
+	char name[4];
+};
+#define to_attr_element(e)	container_of(e, struct attr_element, attr)
+
+struct attr_array {
+	const struct enumerated_attr *base_attr;
+	unsigned int n_elements;
+	struct kobject kobj;
+	struct attr_element elements[0];
+};
+#define to_attr_array(obj)	container_of(obj, struct attr_array, kobj)
+
+static ssize_t
+attr_array_show(struct kobject *kobj, struct attribute *attr, char *buf)
+{
+	struct attr_element *element = to_attr_element(attr);
+	struct attr_array *array = to_attr_array(kobj);
+	ssize_t ret = 0;
+
+	if (array->base_attr->show)
+		ret = array->base_attr->show(kobj->parent, element->idx, buf);
+
+	return ret;
+}
+
+static ssize_t
+attr_array_store(struct kobject *kobj, struct attribute *attr,
+		 const char *buf, size_t count)
+{
+	struct attr_element *element = to_attr_element(attr);
+	struct attr_array *array = to_attr_array(kobj);
+	ssize_t ret = 0;
+
+	if (array->base_attr->store)
+		ret = array->base_attr->store(kobj->parent, element->idx, buf, count);
+
+	return ret;
+}
+
+static struct sysfs_ops attr_array_sysfs_ops = {
+	.show	= attr_array_show,
+	.store	= attr_array_store,
+};
+
+static void attr_array_release(struct kobject *kobj)
+{
+	kfree(to_attr_array(kobj));
+}
+
+static struct kobj_type ktype_attr_array = {
+	.release	= attr_array_release,
+	.sysfs_ops	= &attr_array_sysfs_ops,
+};
+
+
+static int create_array_element(struct attr_array *array,
+				unsigned int idx)
+{
+	struct attr_element *element = &array->elements[idx];
+
+	snprintf(element->name, sizeof(element->name), "%d", idx);
+	element->idx = idx;
+	element->attr = array->base_attr->attr;
+	element->attr.name = element->name;
+
+	return sysfs_create_file(&array->kobj, &element->attr);
+}
+
+static inline void remove_array_element(struct attr_array *array,
+					unsigned int idx)
+{
+	sysfs_remove_file(&array->kobj, &array->elements[idx].attr);
+}
+
+int sysfs_create_array(struct kobject *kobj,
+		       const struct enumerated_attr *attr,
+		       unsigned int n_elements)
+{
+	struct attr_array *array;
+	size_t size;
+	unsigned int i;
+	int error;
+
+	BUG_ON(!kobj || !kobj->dentry);
+	BUG_ON(!attr_name(*attr));
+
+	if (n_elements > 999)
+		return -EINVAL;
+
+	size = sizeof(struct attr_array) +
+	       sizeof(struct attr_element) * n_elements;
+
+	array = kmalloc(size, GFP_KERNEL);
+	if (!array)
+		return -ENOMEM;
+
+	memset(array, 0, size);
+	array->base_attr = attr;
+	array->n_elements = n_elements;
+
+	array->kobj.ktype = &ktype_attr_array;
+	array->kobj.parent = kobj;
+	kobject_set_name(&array->kobj, attr_name(*attr));
+
+	error = kobject_register(&array->kobj);
+	if (error)
+		goto fail;
+
+	for (i = 0; i < n_elements; i++) {
+		error = create_array_element(array, i);
+		if (error) {
+			while (--i)
+				remove_array_element(array, i);
+			goto fail;
+		}
+	}
+
+	return 0;
+
+ fail:
+	kfree(array);
+	return error;
+}
+
+void sysfs_remove_array(struct kobject *kobj,
+			const struct enumerated_attr *attr)
+{
+	struct attr_array *array;
+	struct dentry *dir;
+	unsigned int i;
+
+	dir = sysfs_get_dentry(kobj->dentry, attr_name(*attr));
+
+	if (dir) {
+		array = to_attr_array(to_kobj(dir));
+		for (i = 0; i < array->n_elements; i++)
+			remove_array_element(array, i);
+		kobject_unregister(&array->kobj);
+	}
+
+	dput(dir);
+}
+
+EXPORT_SYMBOL_GPL(sysfs_create_array);
+EXPORT_SYMBOL_GPL(sysfs_remove_array);
Index: dtor/include/linux/sysfs.h
===================================================================
--- dtor.orig/include/linux/sysfs.h
+++ dtor/include/linux/sysfs.h
@@ -26,7 +26,12 @@ struct attribute_group {
 	struct attribute	** attrs;
 };
 
+struct enumerated_attr {
+	struct attribute	attr;
 
+	ssize_t	(*show)(struct kobject *, unsigned int index, char *);
+	ssize_t	(*store)(struct kobject *, unsigned int index, const char *, size_t);
+};
 
 /**
  * Use these macros to make defining attributes easier. See include/linux/device.h
@@ -102,7 +107,7 @@ sysfs_update_file(struct kobject *, cons
 extern void
 sysfs_remove_file(struct kobject *, const struct attribute *);
 
-extern int 
+extern int
 sysfs_create_link(struct kobject * kobj, struct kobject * target, char * name);
 
 extern void
@@ -114,6 +119,9 @@ int sysfs_remove_bin_file(struct kobject
 int sysfs_create_group(struct kobject *, const struct attribute_group *);
 void sysfs_remove_group(struct kobject *, const struct attribute_group *);
 
+int sysfs_create_array(struct kobject *, const struct enumerated_attr *, unsigned int);
+void sysfs_remove_array(struct kobject *, const struct enumerated_attr *);
+
 #else /* CONFIG_SYSFS */
 
 static inline int sysfs_create_dir(struct kobject * k)
@@ -177,6 +185,16 @@ static inline void sysfs_remove_group(st
 	;
 }
 
+static inline int sysfs_create_array(struct kobject * k, const struct enumerated_attr * a, unsigned int n)
+{
+	return 0;
+}
+
+static inline void sysfs_remove_array(struct kobject * k, const struct enumerated_attr * a)
+{
+	;
+}
+
 #endif /* CONFIG_SYSFS */
 
 #endif /* _SYSFS_H_ */
Index: dtor/fs/sysfs/Makefile
===================================================================
--- dtor.orig/fs/sysfs/Makefile
+++ dtor/fs/sysfs/Makefile
@@ -3,4 +3,4 @@
 #
 
 obj-y		:= inode.o file.o dir.o symlink.o mount.o bin.o \
-		   group.o
+		   group.o array.o

[-- Attachment #3: attr-group-array.patch --]
[-- Type: text/x-diff, Size: 7263 bytes --]

===================================================================

sysfs: add support for arrays of groups of attributes:

          ../<group_name>/0/<attr_a>
          ../<group_name>/0/<attr_b>
          ../<group_name>/1/<attr_a>
          ../<group_name>/1/<attr_b>
                 ...
          ../<group_name>/<n>/<attr_a>
          ../<group_name>/<n>/<attr_b>

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>


 fs/sysfs/Makefile      |    2 
 fs/sysfs/group-array.c |  206 +++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/sysfs.h  |   18 ++++
 3 files changed, 225 insertions(+), 1 deletion(-)

Index: dtor/fs/sysfs/Makefile
===================================================================
--- dtor.orig/fs/sysfs/Makefile
+++ dtor/fs/sysfs/Makefile
@@ -3,4 +3,4 @@
 #
 
 obj-y		:= inode.o file.o dir.o symlink.o mount.o bin.o \
-		   group.o array.o
+		   group.o array.o group-array.o
Index: dtor/include/linux/sysfs.h
===================================================================
--- dtor.orig/include/linux/sysfs.h
+++ dtor/include/linux/sysfs.h
@@ -33,6 +33,11 @@ struct enumerated_attr {
 	ssize_t	(*store)(struct kobject *, unsigned int index, const char *, size_t);
 };
 
+struct attribute_group_array {
+	char			* name;
+	struct enumerated_attr	* attrs;
+};
+
 /**
  * Use these macros to make defining attributes easier. See include/linux/device.h
  * for examples..
@@ -122,6 +127,9 @@ void sysfs_remove_group(struct kobject *
 int sysfs_create_array(struct kobject *, const struct enumerated_attr *, unsigned int);
 void sysfs_remove_array(struct kobject *, const struct enumerated_attr *);
 
+int sysfs_create_group_array(struct kobject *, const struct attribute_group_array *, unsigned int);
+void sysfs_remove_group_array(struct kobject *, const struct attribute_group_array *);
+
 #else /* CONFIG_SYSFS */
 
 static inline int sysfs_create_dir(struct kobject * k)
@@ -195,6 +203,16 @@ static inline void sysfs_remove_array(st
 	;
 }
 
+static inline int sysfs_create_group_array(struct kobject * k, const struct attribute_group_array * a, unsigned int n)
+{
+	return 0;
+}
+
+static inline void sysfs_remove_group_array(struct kobject * k, const struct attribute_group_array * a)
+{
+	;
+}
+
 #endif /* CONFIG_SYSFS */
 
 #endif /* _SYSFS_H_ */
Index: dtor/fs/sysfs/group-array.c
===================================================================
--- /dev/null
+++ dtor/fs/sysfs/group-array.c
@@ -0,0 +1,206 @@
+/*
+ * fs/sysfs/group-array.c - Operations for adding/removing arrays of groups
+ *			    of attributes.
+ *
+ * Copyright (c) 2005 Dmitry Torokhov <dtor@mail.ru>
+ *
+ * This file is released under the GPL v2.
+ *
+ */
+
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/dcache.h>
+#include "sysfs.h"
+
+#define to_enumerated_attr(obj)	container_of(obj, struct enumerated_attr, attr)
+
+struct attr_group {
+	struct kobject kobj;
+	struct kobject *attr_owner;
+	unsigned int idx;
+};
+#define to_attr_group(obj)	container_of(obj, struct attr_group, kobj)
+
+struct attr_array {
+	struct kobject kobj;
+	unsigned int n_elements;
+	struct enumerated_attr *attrs;
+};
+#define to_attr_array(obj)	container_of(obj, struct attr_array, kobj)
+
+static ssize_t
+attr_group_show(struct kobject *kobj, struct attribute *attr, char *buf)
+{
+	struct enumerated_attr *eattr = to_enumerated_attr(attr);
+	struct attr_group *group = to_attr_group(kobj);
+	ssize_t ret = 0;
+
+	if (eattr->show)
+		ret = eattr->show(group->attr_owner, group->idx, buf);
+
+	return ret;
+}
+
+static ssize_t
+attr_group_store(struct kobject *kobj, struct attribute *attr,
+		 const char *buf, size_t count)
+{
+	struct enumerated_attr *eattr = to_enumerated_attr(attr);
+	struct attr_group *group = to_attr_group(kobj);
+	ssize_t ret = 0;
+
+	if (eattr->store)
+		ret = eattr->store(group->attr_owner, group->idx, buf, count);
+
+	return ret;
+}
+
+static struct sysfs_ops attr_group_sysfs_ops = {
+	.show	= attr_group_show,
+	.store	= attr_group_store,
+};
+
+static void attr_group_release(struct kobject *kobj)
+{
+	struct attr_group *group = to_attr_group(kobj);
+
+	kobject_put(group->attr_owner);
+	kfree(group);
+}
+
+static struct kobj_type ktype_attr_group = {
+	.release	= attr_group_release,
+	.sysfs_ops	= &attr_group_sysfs_ops,
+};
+
+static void attr_array_release(struct kobject *kobj)
+{
+	kfree(to_attr_array(kobj));
+}
+
+static struct kobj_type ktype_attr_array = {
+	.release	= attr_array_release,
+};
+
+static int create_group(struct attr_array *array, unsigned int idx)
+{
+	struct attr_group *group;
+	struct enumerated_attr *eattr, *eattr2;
+	int err;
+
+	group = kmalloc(sizeof(struct attr_group), GFP_KERNEL);
+	if (!group)
+		return -ENOMEM;
+
+	memset(group, 0, sizeof(struct attr_group));
+	kobject_set_name(&group->kobj, "%d", idx);
+	group->kobj.ktype = &ktype_attr_group;
+	group->kobj.parent = &array->kobj;
+	group->attr_owner = kobject_get(array->kobj.parent);
+	group->idx = idx;
+
+	err = kobject_register(&group->kobj);
+	if (err)
+		goto fail1;
+
+	for (eattr = array->attrs; attr_name(*eattr); eattr++) {
+		err = sysfs_create_file(&group->kobj, &eattr->attr);
+		if (err)
+			goto fail2;
+	}
+
+	return 0;
+
+ fail2:	for (eattr2 = array->attrs; eattr2 != eattr; eattr2++)
+		sysfs_remove_file(&group->kobj, &eattr2->attr);
+ fail1:	kfree(group);
+	return err;
+}
+
+static void remove_group(struct attr_array *array, unsigned int idx)
+{
+	struct attr_group *group;
+	struct enumerated_attr *eattr;
+	struct dentry *dir;
+	char name[4];
+
+	snprintf(name, sizeof(name), "%d", idx);
+	dir = sysfs_get_dentry(array->kobj.dentry, name);
+	if (dir) {
+		group = to_attr_group(to_kobj(dir));
+		for (eattr = array->attrs; attr_name(*eattr); eattr++)
+			sysfs_remove_file(&group->kobj, &eattr->attr);
+		kobject_unregister(&group->kobj);
+	}
+
+	dput(dir);
+}
+
+int sysfs_create_group_array(struct kobject *kobj,
+			     const struct attribute_group_array *a,
+			     unsigned int n_elements)
+{
+	struct attr_array *array;
+	unsigned int i;
+	int error;
+
+	BUG_ON(!kobj || !kobj->dentry);
+	BUG_ON(!a->name);
+
+	if (n_elements > 999)
+		return -EINVAL;
+
+	array = kmalloc(sizeof(struct attr_array), GFP_KERNEL);
+	if (!array)
+		return -ENOMEM;
+
+	memset(array, 0, sizeof(struct attr_array));
+	array->attrs = a->attrs;
+	array->n_elements = n_elements;
+
+	array->kobj.ktype = &ktype_attr_array;
+	array->kobj.parent = kobj;
+	kobject_set_name(&array->kobj, a->name);
+
+	error = kobject_register(&array->kobj);
+	if (error)
+		goto fail;
+
+	for (i = 0; i < n_elements; i++) {
+		error = create_group(array, i);
+		if (error) {
+			while (--i)
+				remove_group(array, i);
+			goto fail;
+		}
+	}
+
+	return 0;
+
+ fail:
+	kfree(array);
+	return error;
+}
+
+void sysfs_remove_group_array(struct kobject *kobj,
+			      const struct attribute_group_array *a)
+{
+	struct attr_array *array;
+	struct dentry *dir;
+	unsigned int i;
+
+	dir = sysfs_get_dentry(kobj->dentry, a->name);
+
+	if (dir) {
+		array = to_attr_array(to_kobj(dir));
+		for (i = 0; i < array->n_elements; i++)
+			remove_group(array, i);
+		kobject_unregister(&array->kobj);
+	}
+
+	dput(dir);
+}
+
+EXPORT_SYMBOL_GPL(sysfs_create_group_array);
+EXPORT_SYMBOL_GPL(sysfs_remove_group_array);

[-- Attachment #4: i8k-cumulative.patch --]
[-- Type: text/x-diff, Size: 32614 bytes --]

 Documentation/kernel-parameters.txt |    3 
 arch/i386/kernel/dmi_scan.c         |    1 
 drivers/char/i8k.c                  | 1005 +++++++++++++++---------------------
 drivers/char/misc.c                 |    4 
 include/linux/dmi.h                 |    1 
 5 files changed, 444 insertions(+), 570 deletions(-)

Index: dtor/arch/i386/kernel/dmi_scan.c
===================================================================
--- dtor.orig/arch/i386/kernel/dmi_scan.c
+++ dtor/arch/i386/kernel/dmi_scan.c
@@ -416,6 +416,7 @@ static void __init dmi_decode(struct dmi
 			dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
 			dmi_printk(("Serial Number: %s\n",
 				dmi_string(dm, data[7])));
+			dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
 			break;
 		case 2:
 			dmi_printk(("Board Vendor: %s\n",
Index: dtor/Documentation/kernel-parameters.txt
===================================================================
--- dtor.orig/Documentation/kernel-parameters.txt
+++ dtor/Documentation/kernel-parameters.txt
@@ -545,6 +545,9 @@ running once the system is up.
 
 	i810=		[HW,DRM]
 
+	i8k.ignore_dmi	[HW] Continue probing hardware even if DMI data
+			indicates that the driver is running on unsupported
+			hardware.
 	i8k.force	[HW] Activate i8k driver even if SMM BIOS signature
 			does not match list of supported models.
 	i8k.power_status
Index: dtor/drivers/char/misc.c
===================================================================
--- dtor.orig/drivers/char/misc.c
+++ dtor/drivers/char/misc.c
@@ -67,7 +67,6 @@ extern int rtc_DP8570A_init(void);
 extern int rtc_MK48T08_init(void);
 extern int pmu_device_init(void);
 extern int tosh_init(void);
-extern int i8k_init(void);
 
 #ifdef CONFIG_PROC_FS
 static void *misc_seq_start(struct seq_file *seq, loff_t *pos)
@@ -317,9 +316,6 @@ static int __init misc_init(void)
 #ifdef CONFIG_TOSHIBA
 	tosh_init();
 #endif
-#ifdef CONFIG_I8K
-	i8k_init();
-#endif
 	if (register_chrdev(MISC_MAJOR,"misc",&misc_fops)) {
 		printk("unable to get major %d for misc devices\n",
 		       MISC_MAJOR);
Index: dtor/include/linux/dmi.h
===================================================================
--- dtor.orig/include/linux/dmi.h
+++ dtor/include/linux/dmi.h
@@ -9,6 +9,7 @@ enum dmi_field {
 	DMI_SYS_VENDOR,
 	DMI_PRODUCT_NAME,
 	DMI_PRODUCT_VERSION,
+	DMI_PRODUCT_SERIAL,
 	DMI_BOARD_VENDOR,
 	DMI_BOARD_NAME,
 	DMI_BOARD_VERSION,
Index: dtor/drivers/char/i8k.c
===================================================================
--- dtor.orig/drivers/char/i8k.c
+++ dtor/drivers/char/i8k.c
@@ -20,13 +20,15 @@
 #include <linux/types.h>
 #include <linux/init.h>
 #include <linux/proc_fs.h>
-#include <linux/apm_bios.h>
+#include <linux/seq_file.h>
+#include <linux/dmi.h>
+#include <linux/device.h>
 #include <asm/uaccess.h>
 #include <asm/io.h>
 
 #include <linux/i8k.h>
 
-#define I8K_VERSION		"1.13 14/05/2002"
+#define I8K_VERSION		"1.14 21/02/2005"
 
 #define I8K_SMM_FN_STATUS	0x0025
 #define I8K_SMM_POWER_STATUS	0x0069
@@ -34,7 +36,8 @@
 #define I8K_SMM_GET_FAN		0x00a3
 #define I8K_SMM_GET_SPEED	0x02a3
 #define I8K_SMM_GET_TEMP	0x10a3
-#define I8K_SMM_GET_DELL_SIG	0xffa3
+#define I8K_SMM_GET_DELL_SIG1	0xfea3
+#define I8K_SMM_GET_DELL_SIG2	0xffa3
 #define I8K_SMM_BIOS_VERSION	0x00a6
 
 #define I8K_FAN_MULT		30
@@ -52,18 +55,7 @@
 
 #define I8K_TEMPERATURE_BUG	1
 
-#define DELL_SIGNATURE		"Dell Computer"
-
-static char *supported_models[] = {
-    "Inspiron",
-    "Latitude",
-    NULL
-};
-
-static char system_vendor[48] = "?";
-static char product_name [48] = "?";
-static char bios_version [4]  = "?";
-static char serial_number[16] = "?";
+static char bios_version[4];
 
 MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
 MODULE_DESCRIPTION("Driver for accessing SMM BIOS on Dell laptops");
@@ -73,6 +65,10 @@ static int force;
 module_param(force, bool, 0);
 MODULE_PARM_DESC(force, "Force loading without checking for supported models");
 
+static int ignore_dmi;
+module_param(ignore_dmi, bool, 0);
+MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
+
 static int restricted;
 module_param(restricted, bool, 0);
 MODULE_PARM_DESC(restricted, "Allow fan control if SYS_ADMIN capability set");
@@ -81,69 +77,76 @@ static int power_status;
 module_param(power_status, bool, 0600);
 MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k");
 
-static ssize_t i8k_read(struct file *, char __user *, size_t, loff_t *);
+static int i8k_open_fs(struct inode *inode, struct file *file);
 static int i8k_ioctl(struct inode *, struct file *, unsigned int,
 		     unsigned long);
 
 static struct file_operations i8k_fops = {
-    .read	= i8k_read,
-    .ioctl	= i8k_ioctl,
+	.open		= i8k_open_fs,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+	.ioctl		= i8k_ioctl,
 };
 
-typedef struct {
-    unsigned int eax;
-    unsigned int ebx __attribute__ ((packed));
-    unsigned int ecx __attribute__ ((packed));
-    unsigned int edx __attribute__ ((packed));
-    unsigned int esi __attribute__ ((packed));
-    unsigned int edi __attribute__ ((packed));
-} SMMRegisters;
-
-typedef struct {
-    u8	type;
-    u8	length;
-    u16	handle;
-} DMIHeader;
+static struct device_driver i8k_driver = {
+	.name		= "i8k",
+	.bus		= &platform_bus_type,
+};
+
+static struct platform_device *i8k_device;
+
+struct smm_regs {
+	unsigned int eax;
+	unsigned int ebx __attribute__ ((packed));
+	unsigned int ecx __attribute__ ((packed));
+	unsigned int edx __attribute__ ((packed));
+	unsigned int esi __attribute__ ((packed));
+	unsigned int edi __attribute__ ((packed));
+};
+
+static inline char *i8k_get_dmi_data(int field)
+{
+	return dmi_get_system_info(field) ? : "N/A";
+}
 
 /*
  * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard.
  */
-static int i8k_smm(SMMRegisters *regs)
+static int i8k_smm(struct smm_regs *regs)
 {
-    int rc;
-    int eax = regs->eax;
+	int rc;
+	int eax = regs->eax;
+
+	asm("pushl %%eax\n\t"
+	    "movl 0(%%eax),%%edx\n\t"
+	    "push %%edx\n\t"
+	    "movl 4(%%eax),%%ebx\n\t"
+	    "movl 8(%%eax),%%ecx\n\t"
+	    "movl 12(%%eax),%%edx\n\t"
+	    "movl 16(%%eax),%%esi\n\t"
+	    "movl 20(%%eax),%%edi\n\t"
+	    "popl %%eax\n\t"
+	    "out %%al,$0xb2\n\t"
+	    "out %%al,$0x84\n\t"
+	    "xchgl %%eax,(%%esp)\n\t"
+	    "movl %%ebx,4(%%eax)\n\t"
+	    "movl %%ecx,8(%%eax)\n\t"
+	    "movl %%edx,12(%%eax)\n\t"
+	    "movl %%esi,16(%%eax)\n\t"
+	    "movl %%edi,20(%%eax)\n\t"
+	    "popl %%edx\n\t"
+	    "movl %%edx,0(%%eax)\n\t"
+	    "lahf\n\t"
+	    "shrl $8,%%eax\n\t"
+	    "andl $1,%%eax\n":"=a"(rc)
+	    :    "a"(regs)
+	    :    "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
 
-    asm("pushl %%eax\n\t" \
-	"movl 0(%%eax),%%edx\n\t" \
-	"push %%edx\n\t" \
-	"movl 4(%%eax),%%ebx\n\t" \
-	"movl 8(%%eax),%%ecx\n\t" \
-	"movl 12(%%eax),%%edx\n\t" \
-	"movl 16(%%eax),%%esi\n\t" \
-	"movl 20(%%eax),%%edi\n\t" \
-	"popl %%eax\n\t" \
-	"out %%al,$0xb2\n\t" \
-	"out %%al,$0x84\n\t" \
-	"xchgl %%eax,(%%esp)\n\t"
-	"movl %%ebx,4(%%eax)\n\t" \
-	"movl %%ecx,8(%%eax)\n\t" \
-	"movl %%edx,12(%%eax)\n\t" \
-	"movl %%esi,16(%%eax)\n\t" \
-	"movl %%edi,20(%%eax)\n\t" \
-	"popl %%edx\n\t" \
-	"movl %%edx,0(%%eax)\n\t" \
-	"lahf\n\t" \
-	"shrl $8,%%eax\n\t" \
-	"andl $1,%%eax\n" \
-	: "=a" (rc)
-	: "a" (regs)
-	: "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory");
-
-    if ((rc != 0) || ((regs->eax & 0xffff) == 0xffff) || (regs->eax == eax)) {
-	return -EINVAL;
-    }
+	if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
+		return -EINVAL;
 
-    return 0;
+	return 0;
 }
 
 /*
@@ -152,24 +155,9 @@ static int i8k_smm(SMMRegisters *regs)
  */
 static int i8k_get_bios_version(void)
 {
-    SMMRegisters regs = { 0, 0, 0, 0, 0, 0 };
-    int rc;
-
-    regs.eax = I8K_SMM_BIOS_VERSION;
-    if ((rc=i8k_smm(&regs)) < 0) {
-	return rc;
-    }
-
-    return regs.eax;
-}
+	struct smm_regs regs = { .eax = I8K_SMM_BIOS_VERSION, };
 
-/*
- * Read the machine id.
- */
-static int i8k_get_serial_number(unsigned char *buff)
-{
-    strlcpy(buff, serial_number, sizeof(serial_number));
-    return 0;
+	return i8k_smm(&regs) ? : regs.eax;
 }
 
 /*
@@ -177,24 +165,22 @@ static int i8k_get_serial_number(unsigne
  */
 static int i8k_get_fn_status(void)
 {
-    SMMRegisters regs = { 0, 0, 0, 0, 0, 0 };
-    int rc;
+	struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, };
+	int rc;
 
-    regs.eax = I8K_SMM_FN_STATUS;
-    if ((rc=i8k_smm(&regs)) < 0) {
-	return rc;
-    }
-
-    switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) {
-    case I8K_FN_UP:
-	return I8K_VOL_UP;
-    case I8K_FN_DOWN:
-	return I8K_VOL_DOWN;
-    case I8K_FN_MUTE:
-	return I8K_VOL_MUTE;
-    default:
-	return 0;
-    }
+	if ((rc = i8k_smm(&regs)) < 0)
+		return rc;
+
+	switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) {
+	case I8K_FN_UP:
+		return I8K_VOL_UP;
+	case I8K_FN_DOWN:
+		return I8K_VOL_DOWN;
+	case I8K_FN_MUTE:
+		return I8K_VOL_MUTE;
+	default:
+		return 0;
+	}
 }
 
 /*
@@ -202,20 +188,13 @@ static int i8k_get_fn_status(void)
  */
 static int i8k_get_power_status(void)
 {
-    SMMRegisters regs = { 0, 0, 0, 0, 0, 0 };
-    int rc;
+	struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, };
+	int rc;
+
+	if ((rc = i8k_smm(&regs)) < 0)
+		return rc;
 
-    regs.eax = I8K_SMM_POWER_STATUS;
-    if ((rc=i8k_smm(&regs)) < 0) {
-	return rc;
-    }
-
-    switch (regs.eax & 0xff) {
-    case I8K_POWER_AC:
-	return I8K_AC;
-    default:
-	return I8K_BATTERY;
-    }
+	return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY;
 }
 
 /*
@@ -223,16 +202,10 @@ static int i8k_get_power_status(void)
  */
 static int i8k_get_fan_status(int fan)
 {
-    SMMRegisters regs = { 0, 0, 0, 0, 0, 0 };
-    int rc;
+	struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, };
 
-    regs.eax = I8K_SMM_GET_FAN;
-    regs.ebx = fan & 0xff;
-    if ((rc=i8k_smm(&regs)) < 0) {
-	return rc;
-    }
-
-    return (regs.eax & 0xff);
+	regs.ebx = fan & 0xff;
+	return i8k_smm(&regs) ? : regs.eax & 0xff;
 }
 
 /*
@@ -240,16 +213,10 @@ static int i8k_get_fan_status(int fan)
  */
 static int i8k_get_fan_speed(int fan)
 {
-    SMMRegisters regs = { 0, 0, 0, 0, 0, 0 };
-    int rc;
-
-    regs.eax = I8K_SMM_GET_SPEED;
-    regs.ebx = fan & 0xff;
-    if ((rc=i8k_smm(&regs)) < 0) {
-	return rc;
-    }
+	struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, };
 
-    return (regs.eax & 0xffff) * I8K_FAN_MULT;
+	regs.ebx = fan & 0xff;
+	return i8k_smm(&regs) ? : (regs.eax & 0xffff) * I8K_FAN_MULT;
 }
 
 /*
@@ -257,532 +224,438 @@ static int i8k_get_fan_speed(int fan)
  */
 static int i8k_set_fan(int fan, int speed)
 {
-    SMMRegisters regs = { 0, 0, 0, 0, 0, 0 };
-    int rc;
+	struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, };
 
-    speed = (speed < 0) ? 0 : ((speed > I8K_FAN_MAX) ? I8K_FAN_MAX : speed);
+	speed = (speed < 0) ? 0 : ((speed > I8K_FAN_MAX) ? I8K_FAN_MAX : speed);
+	regs.ebx = (fan & 0xff) | (speed << 8);
 
-    regs.eax = I8K_SMM_SET_FAN;
-    regs.ebx = (fan & 0xff) | (speed << 8);
-    if ((rc=i8k_smm(&regs)) < 0) {
-	return rc;
-    }
-
-    return (i8k_get_fan_status(fan));
+	return i8k_smm(&regs) ? : i8k_get_fan_status(fan);
 }
 
 /*
  * Read the cpu temperature.
  */
-static int i8k_get_cpu_temp(void)
+static int i8k_get_temp(int sensor)
 {
-    SMMRegisters regs = { 0, 0, 0, 0, 0, 0 };
-    int rc;
-    int temp;
+	struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP, };
+	int rc;
+	int temp;
 
 #ifdef I8K_TEMPERATURE_BUG
-    static int prev = 0;
+	static int prev;
 #endif
+	regs.ebx = sensor & 0xff;
+	if ((rc = i8k_smm(&regs)) < 0)
+		return rc;
 
-    regs.eax = I8K_SMM_GET_TEMP;
-    if ((rc=i8k_smm(&regs)) < 0) {
-	return rc;
-    }
-    temp = regs.eax & 0xff;
+	temp = regs.eax & 0xff;
 
 #ifdef I8K_TEMPERATURE_BUG
-    /*
-     * Sometimes the temperature sensor returns 0x99, which is out of range.
-     * In this case we return (once) the previous cached value. For example:
-     # 1003655137 00000058 00005a4b
-     # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
-     # 1003655139 00000054 00005c52
-     */
-    if (temp > I8K_MAX_TEMP) {
-	temp = prev;
-	prev = I8K_MAX_TEMP;
-    } else {
-	prev = temp;
-    }
+	/*
+	 * Sometimes the temperature sensor returns 0x99, which is out of range.
+	 * In this case we return (once) the previous cached value. For example:
+	 # 1003655137 00000058 00005a4b
+	 # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees
+	 # 1003655139 00000054 00005c52
+	 */
+	if (temp > I8K_MAX_TEMP) {
+		temp = prev;
+		prev = I8K_MAX_TEMP;
+	} else {
+		prev = temp;
+	}
 #endif
 
-    return temp;
+	return temp;
 }
 
-static int i8k_get_dell_signature(void)
+static int i8k_get_dell_signature(int req_fn)
 {
-    SMMRegisters regs = { 0, 0, 0, 0, 0, 0 };
-    int rc;
+	struct smm_regs regs = { .eax = req_fn, };
+	int rc;
 
-    regs.eax = I8K_SMM_GET_DELL_SIG;
-    if ((rc=i8k_smm(&regs)) < 0) {
-	return rc;
-    }
+	if ((rc = i8k_smm(&regs)) < 0)
+		return rc;
 
-    if ((regs.eax == 1145651527) && (regs.edx == 1145392204)) {
-	return 0;
-    } else {
-	return -1;
-    }
+	return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1;
 }
 
 static int i8k_ioctl(struct inode *ip, struct file *fp, unsigned int cmd,
 		     unsigned long arg)
 {
-    int val;
-    int speed;
-    unsigned char buff[16];
-    int __user *argp = (int __user *)arg;
-
-    if (!argp)
-	return -EINVAL;
-
-    switch (cmd) {
-    case I8K_BIOS_VERSION:
-	val = i8k_get_bios_version();
-	break;
-
-    case I8K_MACHINE_ID:
-	memset(buff, 0, 16);
-	val = i8k_get_serial_number(buff);
-	break;
-
-    case I8K_FN_STATUS:
-	val = i8k_get_fn_status();
-	break;
-
-    case I8K_POWER_STATUS:
-	val = i8k_get_power_status();
-	break;
-
-    case I8K_GET_TEMP:
-	val = i8k_get_cpu_temp();
-	break;
-
-    case I8K_GET_SPEED:
-	if (copy_from_user(&val, argp, sizeof(int))) {
-	    return -EFAULT;
-	}
-	val = i8k_get_fan_speed(val);
-	break;
+	int val = 0;
+	int speed;
+	unsigned char buff[16];
+	int __user *argp = (int __user *)arg;
 
-    case I8K_GET_FAN:
-	if (copy_from_user(&val, argp, sizeof(int))) {
-	    return -EFAULT;
-	}
-	val = i8k_get_fan_status(val);
-	break;
+	if (!argp)
+		return -EINVAL;
 
-    case I8K_SET_FAN:
-	if (restricted && !capable(CAP_SYS_ADMIN)) {
-	    return -EPERM;
-	}
-	if (copy_from_user(&val, argp, sizeof(int))) {
-	    return -EFAULT;
-	}
-	if (copy_from_user(&speed, argp+1, sizeof(int))) {
-	    return -EFAULT;
-	}
-	val = i8k_set_fan(val, speed);
-	break;
+	switch (cmd) {
+	case I8K_BIOS_VERSION:
+		val = i8k_get_bios_version();
+		break;
 
-    default:
-	return -EINVAL;
-    }
-
-    if (val < 0) {
-	return val;
-    }
-
-    switch (cmd) {
-    case I8K_BIOS_VERSION:
-	if (copy_to_user(argp, &val, 4)) {
-	    return -EFAULT;
-	}
-	break;
-    case I8K_MACHINE_ID:
-	if (copy_to_user(argp, buff, 16)) {
-	    return -EFAULT;
+	case I8K_MACHINE_ID:
+		memset(buff, 0, 16);
+		strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL), sizeof(buff));
+		break;
+
+	case I8K_FN_STATUS:
+		val = i8k_get_fn_status();
+		break;
+
+	case I8K_POWER_STATUS:
+		val = i8k_get_power_status();
+		break;
+
+	case I8K_GET_TEMP:
+		val = i8k_get_temp(0);
+		break;
+
+	case I8K_GET_SPEED:
+		if (copy_from_user(&val, argp, sizeof(int)))
+			return -EFAULT;
+
+		val = i8k_get_fan_speed(val);
+		break;
+
+	case I8K_GET_FAN:
+		if (copy_from_user(&val, argp, sizeof(int)))
+			return -EFAULT;
+
+		val = i8k_get_fan_status(val);
+		break;
+
+	case I8K_SET_FAN:
+		if (restricted && !capable(CAP_SYS_ADMIN))
+			return -EPERM;
+
+		if (copy_from_user(&val, argp, sizeof(int)))
+			return -EFAULT;
+
+		if (copy_from_user(&speed, argp + 1, sizeof(int)))
+			return -EFAULT;
+
+		val = i8k_set_fan(val, speed);
+		break;
+
+	default:
+		return -EINVAL;
 	}
-	break;
-    default:
-	if (copy_to_user(argp, &val, sizeof(int))) {
-	    return -EFAULT;
+
+	if (val < 0)
+		return val;
+
+	switch (cmd) {
+	case I8K_BIOS_VERSION:
+		if (copy_to_user(argp, &val, 4))
+			return -EFAULT;
+
+		break;
+	case I8K_MACHINE_ID:
+		if (copy_to_user(argp, buff, 16))
+			return -EFAULT;
+
+		break;
+	default:
+		if (copy_to_user(argp, &val, sizeof(int)))
+			return -EFAULT;
+
+		break;
 	}
-	break;
-    }
 
-    return 0;
+	return 0;
 }
 
 /*
  * Print the information for /proc/i8k.
  */
-static int i8k_get_info(char *buffer, char **start, off_t fpos, int length)
+static int i8k_proc_show(struct seq_file *seq, void *offset)
 {
-    int n, fn_key, cpu_temp, ac_power;
-    int left_fan, right_fan, left_speed, right_speed;
-
-    cpu_temp     = i8k_get_cpu_temp();			/* 11100 µs */
-    left_fan     = i8k_get_fan_status(I8K_FAN_LEFT);	/*   580 µs */
-    right_fan    = i8k_get_fan_status(I8K_FAN_RIGHT);	/*   580 µs */
-    left_speed   = i8k_get_fan_speed(I8K_FAN_LEFT);	/*   580 µs */
-    right_speed  = i8k_get_fan_speed(I8K_FAN_RIGHT);	/*   580 µs */
-    fn_key       = i8k_get_fn_status();			/*   750 µs */
-    if (power_status) {
-	ac_power = i8k_get_power_status();		/* 14700 µs */
-    } else {
-	ac_power = -1;
-    }
-
-    /*
-     * Info:
-     *
-     * 1)  Format version (this will change if format changes)
-     * 2)  BIOS version
-     * 3)  BIOS machine ID
-     * 4)  Cpu temperature
-     * 5)  Left fan status
-     * 6)  Right fan status
-     * 7)  Left fan speed
-     * 8)  Right fan speed
-     * 9)  AC power
-     * 10) Fn Key status
-     */
-    n = sprintf(buffer, "%s %s %s %d %d %d %d %d %d %d\n",
-		I8K_PROC_FMT,
-		bios_version,
-		serial_number,
-		cpu_temp,
-		left_fan,
-		right_fan,
-		left_speed,
-		right_speed,
-		ac_power,
-		fn_key);
-
-    return n;
-}
-
-static ssize_t i8k_read(struct file *f, char __user *buffer, size_t len, loff_t *fpos)
-{
-    int n;
-    char info[128];
-
-    n = i8k_get_info(info, NULL, 0, 128);
-    if (n <= 0) {
-	return n;
-    }
-
-    if (*fpos >= n) {
-	return 0;
-    }
+	int fn_key, cpu_temp, ac_power;
+	int left_fan, right_fan, left_speed, right_speed;
 
-    if ((*fpos + len) >= n) {
-	len = n - *fpos;
-    }
+	cpu_temp	= i8k_get_temp(0);			/* 11100 µs */
+	left_fan	= i8k_get_fan_status(I8K_FAN_LEFT);	/*   580 µs */
+	right_fan	= i8k_get_fan_status(I8K_FAN_RIGHT);	/*   580 µs */
+	left_speed	= i8k_get_fan_speed(I8K_FAN_LEFT);	/*   580 µs */
+	right_speed	= i8k_get_fan_speed(I8K_FAN_RIGHT);	/*   580 µs */
+	fn_key		= i8k_get_fn_status();			/*   750 µs */
+	if (power_status)
+		ac_power = i8k_get_power_status();		/* 14700 µs */
+	else
+		ac_power = -1;
 
-    if (copy_to_user(buffer, info, len) != 0) {
-	return -EFAULT;
-    }
-
-    *fpos += len;
-    return len;
+	/*
+	 * Info:
+	 *
+	 * 1)  Format version (this will change if format changes)
+	 * 2)  BIOS version
+	 * 3)  BIOS machine ID
+	 * 4)  Cpu temperature
+	 * 5)  Left fan status
+	 * 6)  Right fan status
+	 * 7)  Left fan speed
+	 * 8)  Right fan speed
+	 * 9)  AC power
+	 * 10) Fn Key status
+	 */
+	return seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n",
+			  I8K_PROC_FMT,
+			  bios_version,
+			  dmi_get_system_info(DMI_PRODUCT_SERIAL) ? : "N/A",
+			  cpu_temp,
+			  left_fan, right_fan, left_speed, right_speed,
+			  ac_power, fn_key);
 }
 
-static char* __init string_trim(char *s, int size)
+static int i8k_open_fs(struct inode *inode, struct file *file)
 {
-    int len;
-    char *p;
-
-    if ((len = strlen(s)) > size) {
-	len = size;
-    }
+	return single_open(file, i8k_proc_show, NULL);
+}
 
-    for (p=s+len-1; len && (*p==' '); len--,p--) {
-	*p = '\0';
-    }
 
-    return s;
+static ssize_t i8k_sysfs_temp_show(struct kobject *kobj, unsigned int idx, char *buf)
+{
+	int temp = i8k_get_temp(idx);
+	return temp < 0 ? -EIO : sprintf(buf, "%d\n", temp);
 }
 
-/* DMI code, stolen from arch/i386/kernel/dmi_scan.c */
+static struct enumerated_attr i8k_temp_attr =
+	__ATTR(temp, 0444, i8k_sysfs_temp_show, NULL);
 
-/*
- * |<-- dmi->length -->|
- * |                   |
- * |dmi header    s=N  | string1,\0, ..., stringN,\0, ..., \0
- *                |                       |
- *                +-----------------------+
- */
-static char* __init dmi_string(DMIHeader *dmi, u8 s)
+static ssize_t i8k_sysfs_fan_show(struct kobject *kobj, unsigned int idx, char *buf)
+{
+	int status = i8k_get_fan_status(idx);
+	return status < 0 ? -EIO : sprintf(buf, "%d\n", status);
+}
+
+static ssize_t i8k_sysfs_fan_set(struct kobject *kobj, unsigned int idx, const char *buf, size_t count)
 {
-    u8 *p;
+	unsigned long state;
+	char *rest;
 
-    if (!s) {
-	return "";
-    }
-    s--;
+	if (restricted && !capable(CAP_SYS_ADMIN))
+		return -EPERM;
 
-    p = (u8 *)dmi + dmi->length;
-    while (s > 0) {
-	p += strlen(p);
-	p++;
-	s--;
-    }
+	state = simple_strtoul(buf, &rest, 10);
+	if (*rest || state > I8K_FAN_MAX)
+		return -EINVAL;
 
-    return p;
+	if (i8k_set_fan(idx, state) < 0)
+		return -EIO;
+
+	return count;
 }
 
-static void __init dmi_decode(DMIHeader *dmi)
+static ssize_t i8k_sysfs_fan_speed_show(struct kobject *kobj, unsigned int idx, char *buf)
 {
-    u8 *data = (u8 *) dmi;
-    char *p;
+	int speed = i8k_get_fan_speed(idx);
+	return speed < 0 ? -EIO : sprintf(buf, "%d\n", speed);
+}
 
-#ifdef I8K_DEBUG
-    int i;
-    printk("%08x ", (int)data);
-    for (i=0; i<data[1] && i<64; i++) {
-	printk("%02x ", data[i]);
-    }
-    printk("\n");
-#endif
+static struct enumerated_attr i8k_fan_attrs[] = {
+	__ATTR(state, 0644, i8k_sysfs_fan_show, i8k_sysfs_fan_set),
+	__ATTR(speed, 0444, i8k_sysfs_fan_speed_show, NULL),
+	__ATTR_NULL
+};
 
-    switch (dmi->type) {
-    case  0:	/* BIOS Information */
-	p = dmi_string(dmi,data[5]);
-	if (*p) {
-	    strlcpy(bios_version, p, sizeof(bios_version));
-	    string_trim(bios_version, sizeof(bios_version));
-	}
-	break;	
-    case 1:	/* System Information */
-	p = dmi_string(dmi,data[4]);
-	if (*p) {
-	    strlcpy(system_vendor, p, sizeof(system_vendor));
-	    string_trim(system_vendor, sizeof(system_vendor));
-	}
-	p = dmi_string(dmi,data[5]);
-	if (*p) {
-	    strlcpy(product_name, p, sizeof(product_name));
-	    string_trim(product_name, sizeof(product_name));
-	}
-	p = dmi_string(dmi,data[7]);
-	if (*p) {
-	    strlcpy(serial_number, p, sizeof(serial_number));
-	    string_trim(serial_number, sizeof(serial_number));
-	}
-	break;
-    }
-}
+static struct attribute_group_array i8k_fan_attr_array = {
+	.name = "fan",
+	.attrs = i8k_fan_attrs,
+};
 
-static int __init dmi_table(u32 base, int len, int num, void (*fn)(DMIHeader*))
+static ssize_t i8k_sysfs_power_status_show(struct device *dev, char *buf)
 {
-    u8 *buf;
-    u8 *data;
-    DMIHeader *dmi;
-    int i = 1;
-
-    buf = ioremap(base, len);
-    if (buf == NULL) {
-	return -1;
-    }
-    data = buf;
-
-    /*
-     * Stop when we see al the items the table claimed to have
-     * or we run off the end of the table (also happens)
-     */
-    while ((i<num) && ((data-buf) < len)) {
-	dmi = (DMIHeader *)data;
-	/*
-	 * Avoid misparsing crud if the length of the last
-	 * record is crap
-	 */
-	if ((data-buf+dmi->length) >= len) {
-	    break;
-	}
-	fn(dmi);
-	data += dmi->length;
-	/*
-	 * Don't go off the end of the data if there is
-	 * stuff looking like string fill past the end
-	 */
-	while (((data-buf) < len) && (*data || data[1])) {
-	    data++;
-	}
-	data += 2;
-	i++;
-    }
-    iounmap(buf);
-
-    return 0;
-}
-
-static int __init dmi_iterate(void (*decode)(DMIHeader *))
-{
-	unsigned char buf[20];
-	void __iomem *p = ioremap(0xe0000, 0x20000), *q;
-
-	if (!p)
-		return -1;
-
-	for (q = p; q < p + 0x20000; q += 16) {
-		memcpy_fromio(buf, q, 20);
-		if (memcmp(buf, "_DMI_", 5)==0) {
-			u16 num  = buf[13]<<8  | buf[12];
-			u16 len  = buf [7]<<8  | buf [6];
-			u32 base = buf[11]<<24 | buf[10]<<16 | buf[9]<<8 | buf[8];
-#ifdef I8K_DEBUG
-			printk(KERN_INFO "DMI %d.%d present.\n",
-			   buf[14]>>4, buf[14]&0x0F);
-			printk(KERN_INFO "%d structures occupying %d bytes.\n",
-			   buf[13]<<8 | buf[12],
-			   buf [7]<<8 | buf[6]);
-			printk(KERN_INFO "DMI table at 0x%08X.\n",
-			   buf[11]<<24 | buf[10]<<16 | buf[9]<<8 | buf[8]);
-#endif
-			if (dmi_table(base, len, num, decode)==0) {
-				iounmap(p);
-				return 0;
-			}
-		}
-	}
-	iounmap(p);
-	return -1;
+	int status = power_status ? i8k_get_power_status() : -1;
+	return status < 0 ? -EIO : sprintf(buf, "%d\n", status);
 }
-/* end of DMI code */
 
-/*
- * Get DMI information.
- */
-static int __init i8k_dmi_probe(void)
-{
-    char **p;
+static struct device_attribute i8k_power_status_attr =
+	__ATTR(power_status, 0444, i8k_sysfs_power_status_show, NULL);
 
-    if (dmi_iterate(dmi_decode) != 0) {
-	printk(KERN_INFO "i8k: unable to get DMI information\n");
-	return -ENODEV;
-    }
-
-    if (strncmp(system_vendor,DELL_SIGNATURE,strlen(DELL_SIGNATURE)) != 0) {
-	printk(KERN_INFO "i8k: not running on a Dell system\n");
-	return -ENODEV;
-    }
-
-    for (p=supported_models; ; p++) {
-	if (!*p) {
-	    printk(KERN_INFO "i8k: unsupported model: %s\n", product_name);
-	    return -ENODEV;
-	}
-	if (strncmp(product_name,*p,strlen(*p)) == 0) {
-	    break;
-	}
-    }
 
-    return 0;
-}
+static struct dmi_system_id __initdata i8k_dmi_table[] = {
+	{
+		.ident = "Dell Inspiron",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
+		},
+	},
+	{
+		.ident = "Dell Latitude",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
+		},
+	},
+	{
+		.ident = "Dell Inspiron 2",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
+		},
+	},
+	{
+		.ident = "Dell Latitude 2",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
+		},
+	},
+	{ }
+};
 
 /*
  * Probe for the presence of a supported laptop.
  */
 static int __init i8k_probe(void)
 {
-    char buff[4];
-    int version;
-    int smm_found = 0;
-
-    /*
-     * Get DMI information
-     */
-    if (i8k_dmi_probe() != 0) {
-	printk(KERN_INFO "i8k: vendor=%s, model=%s, version=%s\n",
-	       system_vendor, product_name, bios_version);
-    }
-
-    /*
-     * Get SMM Dell signature
-     */
-    if (i8k_get_dell_signature() != 0) {
-	printk(KERN_INFO "i8k: unable to get SMM Dell signature\n");
-    } else {
-	smm_found = 1;
-    }
-
-    /*
-     * Get SMM BIOS version.
-     */
-    version = i8k_get_bios_version();
-    if (version <= 0) {
-	printk(KERN_INFO "i8k: unable to get SMM BIOS version\n");
-    } else {
-	smm_found = 1;
-	buff[0] = (version >> 16) & 0xff;
-	buff[1] = (version >>  8) & 0xff;
-	buff[2] = (version)       & 0xff;
-	buff[3] = '\0';
+	char buff[4];
+	int version;
+
 	/*
-	 * If DMI BIOS version is unknown use SMM BIOS version.
+	 * Get DMI information
 	 */
-	if (bios_version[0] == '?') {
-	    strcpy(bios_version, buff);
+	if (!dmi_check_system(i8k_dmi_table)) {
+		if (!ignore_dmi && !force)
+			return -ENODEV;
+
+		printk(KERN_INFO "i8k: not running on a supported Dell system.\n");
+		printk(KERN_INFO "i8k: vendor=%s, model=%s, version=%s\n",
+			i8k_get_dmi_data(DMI_SYS_VENDOR),
+			i8k_get_dmi_data(DMI_PRODUCT_NAME),
+			i8k_get_dmi_data(DMI_BIOS_VERSION));
 	}
+
+	strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION), sizeof(bios_version));
+
 	/*
-	 * Check if the two versions match.
+	 * Get SMM Dell signature
 	 */
-	if (strncmp(buff,bios_version,sizeof(bios_version)) != 0) {
-	    printk(KERN_INFO "i8k: BIOS version mismatch: %s != %s\n",
-		   buff, bios_version);
+	if (i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG1) &&
+	    i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) {
+		printk(KERN_ERR "i8k: unable to get SMM Dell signature\n");
+		if (!force)
+			return -ENODEV;
 	}
-    }
 
-    if (!smm_found && !force) {
-	return -ENODEV;
-    }
+	/*
+	 * Get SMM BIOS version.
+	 */
+	version = i8k_get_bios_version();
+	if (version <= 0) {
+		printk(KERN_WARNING "i8k: unable to get SMM BIOS version\n");
+	} else {
+		buff[0] = (version >> 16) & 0xff;
+		buff[1] = (version >> 8) & 0xff;
+		buff[2] = (version) & 0xff;
+		buff[3] = '\0';
+		/*
+		 * If DMI BIOS version is unknown use SMM BIOS version.
+		 */
+		if (!dmi_get_system_info(DMI_BIOS_VERSION))
+			strlcpy(bios_version, buff, sizeof(bios_version));
+
+		/*
+		 * Check if the two versions match.
+		 */
+		if (strncmp(buff, bios_version, sizeof(bios_version)) != 0)
+			printk(KERN_WARNING "i8k: BIOS version mismatch: %s != %s\n",
+				buff, bios_version);
+	}
 
-    return 0;
+	return 0;
 }
 
-#ifdef MODULE
-static
-#endif
-int __init i8k_init(void)
+static int __init i8k_create_sysfs_files(void)
 {
-    struct proc_dir_entry *proc_i8k;
+	int err, num;
+
+	err = device_create_file(&i8k_device->dev, &i8k_power_status_attr);
+	if (err)
+		return err;
 
-    /* Are we running on an supported laptop? */
-    if (i8k_probe() != 0) {
-	return -ENODEV;
-    }
+	for (num = 0; i8k_get_fan_status(num) >= 0; num++)
+		/* empty */;
 
-    /* Register the proc entry */
-    proc_i8k = create_proc_info_entry("i8k", 0, NULL, i8k_get_info);
-    if (!proc_i8k) {
-	return -ENOENT;
-    }
-    proc_i8k->proc_fops = &i8k_fops;
-    proc_i8k->owner = THIS_MODULE;
+	err = sysfs_create_group_array(&i8k_device->dev.kobj, &i8k_fan_attr_array, num);
+	if (err)
+		goto fail1;
 
-    printk(KERN_INFO
-	   "Dell laptop SMM driver v%s Massimo Dal Zotto (dz@debian.org)\n",
-	   I8K_VERSION);
+	for (num = 0; i8k_get_temp(num) >= 0; num++)
+		/* empty */;
+
+	err = sysfs_create_array(&i8k_device->dev.kobj, &i8k_temp_attr, num);
+	if (err)
+		goto fail2;
+
+	return 0;
 
-    return 0;
+fail2:	sysfs_remove_group_array(&i8k_device->dev.kobj, &i8k_fan_attr_array);
+fail1:	device_remove_file(&i8k_device->dev, &i8k_power_status_attr);
+	return err;
 }
 
-#ifdef MODULE
-int init_module(void)
+static void __exit i8k_remove_sysfs_files(void)
 {
-    return i8k_init();
+	sysfs_remove_array(&i8k_device->dev.kobj, &i8k_temp_attr);
+	sysfs_remove_group_array(&i8k_device->dev.kobj, &i8k_fan_attr_array);
+	device_remove_file(&i8k_device->dev, &i8k_power_status_attr);
 }
 
-void cleanup_module(void)
+static int __init i8k_init(void)
 {
-    /* Remove the proc entry */
-    remove_proc_entry("i8k", NULL);
+	struct proc_dir_entry *proc_i8k;
+	int err;
 
-    printk(KERN_INFO "i8k: module unloaded\n");
+	/* Are we running on an supported laptop? */
+	if (i8k_probe())
+		return -ENODEV;
+
+	/* Register the proc entry */
+	proc_i8k = create_proc_entry("i8k", 0, NULL);
+	if (!proc_i8k)
+		return -ENOENT;
+
+	proc_i8k->proc_fops = &i8k_fops;
+	proc_i8k->owner = THIS_MODULE;
+
+	err = driver_register(&i8k_driver);
+	if (err)
+		goto fail1;
+
+	i8k_device = platform_device_register_simple("i8k", -1, NULL, 0);
+	if (IS_ERR(i8k_device)) {
+		err = PTR_ERR(i8k_device);
+		goto fail2;
+	}
+
+	err = i8k_create_sysfs_files();
+	if (err)
+		goto fail3;
+
+	printk(KERN_INFO
+	       "Dell laptop SMM driver v%s Massimo Dal Zotto (dz@debian.org)\n",
+	       I8K_VERSION);
+
+	return 0;
+
+fail3:	platform_device_unregister(i8k_device);
+fail2:	driver_unregister(&i8k_driver);
+fail1:	remove_proc_entry("i8k", NULL);
+	return err;
+}
+
+static void __exit i8k_exit(void)
+{
+	i8k_remove_sysfs_files();
+	platform_device_unregister(i8k_device);
+	driver_unregister(&i8k_driver);
+	remove_proc_entry("i8k", NULL);
 }
-#endif
 
-/* end of file */
+module_init(i8k_init);
+module_exit(i8k_exit);