[PATCH] I2C: port smsc47m1 to 2.6

Jean Delvare khali at linux-fr.org
Sun Aug 8 17:45:58 CEST 2004


Hi Greg,

Here is my port of the smsc47m1 i2c hardware monitoring driver to Linux
2.6. The original driver was written by Mark D. Studebaker, and my work
is based on a preliminary port by Gabriele Gorla, who came in with an
almost finished driver, but vanished before cleaning it up. I finished
the job and improved things a bit. Credits go to Ivars Strazdins and
Cassio Freitas for testing the driver (having no hardware, I couldn't
test the code myself).

Please consider for inclusion into your kernel tree.

I plan to add an automatic fan clock divider selection feature at some
later point in the future. But one thing at a time, let's begin with
this working piece of code.

Thanks.

Signed-off-by: Jean Delvare <khali at linux-fr dot org>

diff -ruN linux-2.6.8-rc2/drivers/i2c/chips.orig/Kconfig linux-2.6.8-rc2/drivers/i2c/chips/Kconfig
--- linux-2.6.8-rc2/drivers/i2c/chips.orig/Kconfig	2004-07-19 21:49:57.000000000 +0200
+++ linux-2.6.8-rc2/drivers/i2c/chips/Kconfig	2004-07-21 20:02:28.000000000 +0200
@@ -191,6 +191,19 @@
 	  This driver can also be built as a module.  If so, the module
 	  will be called max1619.
 
+config SENSORS_SMSC47M1
+	tristate "SMSC LPC47M10x and compatibles"
+	depends on I2C && EXPERIMENTAL
+	select I2C_SENSOR
+	select I2C_ISA
+	help
+	  If you say yes here you get support for the integrated fan
+	  monitoring and control capabilities of the SMSC LPC47B27x,
+	  LPC47M10x, LPC47M13x and LPC47M14x chips.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called smsc47m1.
+
 config SENSORS_VIA686A
 	tristate "VIA686A"
 	depends on I2C && EXPERIMENTAL
diff -ruN linux-2.6.8-rc2/drivers/i2c/chips.orig/Makefile linux-2.6.8-rc2/drivers/i2c/chips/Makefile
--- linux-2.6.8-rc2/drivers/i2c/chips.orig/Makefile	2004-07-19 21:49:57.000000000 +0200
+++ linux-2.6.8-rc2/drivers/i2c/chips/Makefile	2004-07-19 21:58:44.000000000 +0200
@@ -26,6 +26,7 @@
 obj-$(CONFIG_SENSORS_PCF8574)	+= pcf8574.o
 obj-$(CONFIG_SENSORS_PCF8591)	+= pcf8591.o
 obj-$(CONFIG_SENSORS_RTC8564)	+= rtc8564.o
+obj-$(CONFIG_SENSORS_SMSC47M1)	+= smsc47m1.o
 obj-$(CONFIG_SENSORS_VIA686A)	+= via686a.o
 obj-$(CONFIG_SENSORS_W83L785TS)	+= w83l785ts.o
 
diff -ruN linux-2.6.8-rc2/drivers/i2c/chips.orig/smsc47m1.c linux-2.6.8-rc2/drivers/i2c/chips/smsc47m1.c
--- linux-2.6.8-rc2/drivers/i2c/chips.orig/smsc47m1.c	1970-01-01 01:00:00.000000000 +0100
+++ linux-2.6.8-rc2/drivers/i2c/chips/smsc47m1.c	2004-08-05 09:01:06.000000000 +0200
@@ -0,0 +1,579 @@
+/*
+    smsc47m1.c - Part of lm_sensors, Linux kernel modules
+                 for hardware monitoring
+
+    Supports the SMSC LPC47B27x, LPC47M10x, LPC47M13x and LPC47M14x
+    Super-I/O chips.
+
+    Copyright (C) 2002 Mark D. Studebaker <mdsxyz123 at yahoo.com>
+    Copyright (C) 2004 Jean Delvare <khali at linux-fr.org>
+    Ported to Linux 2.6 by Gabriele Gorla <gorlik at yahoo.com>
+                        and Jean Delvare
+
+    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/module.h>
+#include <linux/slab.h>
+#include <linux/ioport.h>
+#include <linux/i2c.h>
+#include <linux/i2c-sensor.h>
+#include <linux/init.h>
+#include <asm/io.h>
+
+static unsigned short normal_i2c[] = { I2C_CLIENT_END };
+static unsigned short normal_i2c_range[] = { I2C_CLIENT_END };
+/* Address is autodetected, there is no default value */
+static unsigned int normal_isa[] = { 0x0000, I2C_CLIENT_ISA_END };
+static unsigned int normal_isa_range[] = { I2C_CLIENT_ISA_END };
+static struct i2c_force_data forces[] = {{NULL}};
+
+enum chips { any_chip, smsc47m1 };
+static struct i2c_address_data addr_data = {
+	.normal_i2c		= normal_i2c,
+	.normal_i2c_range	= normal_i2c_range,
+	.normal_isa		= normal_isa,
+	.normal_isa_range	= normal_isa_range,
+	.probe			= normal_i2c,		/* cheat */
+	.probe_range		= normal_i2c_range,	/* cheat */
+	.ignore			= normal_i2c,		/* cheat */
+	.ignore_range		= normal_i2c_range,	/* cheat */
+	.forces			= forces,
+};
+
+/* Super-I/0 registers and commands */
+
+#define	REG	0x2e	/* The register to read/write */
+#define	VAL	0x2f	/* The value to read/write */
+
+static inline void
+superio_outb(int reg, int val)
+{
+	outb(reg, REG);
+	outb(val, VAL);
+}
+
+static inline int
+superio_inb(int reg)
+{
+	outb(reg, REG);
+	return inb(VAL);
+}
+
+/* logical device for fans is 0x0A */
+#define superio_select() superio_outb(0x07, 0x0A)
+
+static inline void
+superio_enter(void)
+{
+	outb(0x55, REG);
+}
+
+static inline void
+superio_exit(void)
+{
+	outb(0xAA, REG);
+}
+
+#define SUPERIO_REG_ACT		0x30
+#define SUPERIO_REG_BASE	0x60
+#define SUPERIO_REG_DEVID	0x20
+
+/* Logical device registers */
+
+#define SMSC_EXTENT		0x80
+
+/* nr is 0 or 1 in the macros below */
+#define SMSC47M1_REG_ALARM		0x04
+#define SMSC47M1_REG_TPIN(nr)		(0x34 - (nr))
+#define SMSC47M1_REG_PPIN(nr)		(0x36 - (nr))
+#define SMSC47M1_REG_PWM(nr)		(0x56 + (nr))
+#define SMSC47M1_REG_FANDIV		0x58
+#define SMSC47M1_REG_FAN(nr)		(0x59 + (nr))
+#define SMSC47M1_REG_FAN_PRELOAD(nr)	(0x5B + (nr))
+
+#define MIN_FROM_REG(reg,div)		((reg)>=192 ? 0 : \
+					 983040/((192-(reg))*(div)))
+#define FAN_FROM_REG(reg,div,preload)	((reg)<=(preload) || (reg)==255 ? 0 : \
+					 983040/(((reg)-(preload))*(div)))
+#define DIV_FROM_REG(reg)		(1 << (reg))
+#define PWM_FROM_REG(reg)		(((reg) & 0x7E) << 1)
+#define PWM_EN_FROM_REG(reg)		((~(reg)) & 0x01)
+#define PWM_TO_REG(reg)			(((reg) >> 1) & 0x7E)
+
+struct smsc47m1_data {
+	struct i2c_client client;
+	struct semaphore lock;
+	int sysctl_id;
+
+	struct semaphore update_lock;
+	unsigned long last_updated;	/* In jiffies */
+
+	u8 fan[2];		/* Register value */
+	u8 fan_preload[2];	/* Register value */
+	u8 fan_div[2];		/* Register encoding, shifted right */
+	u8 alarms;		/* Register encoding */
+	u8 pwm[2];		/* Register value (bit 7 is enable) */
+};
+
+
+static int smsc47m1_attach_adapter(struct i2c_adapter *adapter);
+static int smsc47m1_find(int *address);
+static int smsc47m1_detect(struct i2c_adapter *adapter, int address, int kind);
+static int smsc47m1_detach_client(struct i2c_client *client);
+
+static int smsc47m1_read_value(struct i2c_client *client, u8 reg);
+static void smsc47m1_write_value(struct i2c_client *client, u8 reg, u8 value);
+
+static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
+		int init);
+
+
+static int smsc47m1_id;
+
+static struct i2c_driver smsc47m1_driver = {
+	.owner		= THIS_MODULE,
+	.name		= "smsc47m1",
+	.id		= I2C_DRIVERID_SMSC47M1,
+	.flags		= I2C_DF_NOTIFY,
+	.attach_adapter	= smsc47m1_attach_adapter,
+	.detach_client	= smsc47m1_detach_client,
+};
+
+/* nr is 0 or 1 in the callback functions below */
+
+static ssize_t get_fan(struct device *dev, char *buf, int nr)
+{
+	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
+	/* This chip (stupidly) stops monitoring fan speed if PWM is
+	   enabled and duty cycle is 0%. This is fine if the monitoring
+	   and control concern the same fan, but troublesome if they are
+	   not (which could as well happen). */
+	int rpm = (data->pwm[nr] & 0x7F) == 0x00 ? 0 :
+		  FAN_FROM_REG(data->fan[nr],
+			       DIV_FROM_REG(data->fan_div[nr]),
+			       data->fan_preload[nr]);
+	return sprintf(buf, "%d\n", rpm);
+}
+
+static ssize_t get_fan_min(struct device *dev, char *buf, int nr)
+{
+	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
+	int rpm = MIN_FROM_REG(data->fan_preload[nr],
+			       DIV_FROM_REG(data->fan_div[nr]));
+	return sprintf(buf, "%d\n", rpm);
+}
+
+static ssize_t get_fan_div(struct device *dev, char *buf, int nr)
+{
+	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
+	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]));
+}
+
+static ssize_t get_fan_pwm(struct device *dev, char *buf, int nr)
+{
+	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
+	return sprintf(buf, "%d\n", PWM_FROM_REG(data->pwm[nr]));
+}
+
+static ssize_t get_fan_pwm_en(struct device *dev, char *buf, int nr)
+{
+	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
+	return sprintf(buf, "%d\n", PWM_EN_FROM_REG(data->pwm[nr]));
+}
+
+static ssize_t get_alarms(struct device *dev, char *buf)
+{
+	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
+	return sprintf(buf, "%d\n", data->alarms);
+}
+
+static ssize_t set_fan_min(struct device *dev, const char *buf,
+		size_t count, int nr)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct smsc47m1_data *data = i2c_get_clientdata(client);
+
+	long rpmdiv = simple_strtol(buf, NULL, 10)
+		    * DIV_FROM_REG(data->fan_div[nr]);
+
+	if (983040 > 192 * rpmdiv || 2 * rpmdiv > 983040)
+		return -EINVAL;
+
+	data->fan_preload[nr] = 192 - ((983040 + rpmdiv / 2) / rpmdiv);
+	smsc47m1_write_value(client, SMSC47M1_REG_FAN_PRELOAD(nr),
+			     data->fan_preload[nr]);
+
+	return count;
+}
+
+/* Note: we save and restore the fan minimum here, because its value is
+   determined in part by the fan clock divider.  This follows the principle
+   of least suprise; the user doesn't expect the fan minimum to change just
+   because the divider changed. */
+static ssize_t set_fan_div(struct device *dev, const char *buf,
+		size_t count, int nr)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct smsc47m1_data *data = i2c_get_clientdata(client);
+
+	long new_div = simple_strtol(buf, NULL, 10), tmp;
+	u8 old_div = DIV_FROM_REG(data->fan_div[nr]);
+
+	if (new_div == old_div) /* No change */
+		return count;
+	switch (new_div) {
+	case 1: data->fan_div[nr] = 0; break;
+	case 2: data->fan_div[nr] = 1; break;
+	case 4: data->fan_div[nr] = 2; break;
+	case 8: data->fan_div[nr] = 3; break;
+	default: return -EINVAL;
+	}
+
+	tmp = smsc47m1_read_value(client, SMSC47M1_REG_FANDIV) & 0x0F;
+	tmp |= (data->fan_div[0] << 4) | (data->fan_div[1] << 6);
+	smsc47m1_write_value(client, SMSC47M1_REG_FANDIV, tmp);
+
+	/* Preserve fan min */
+	tmp = 192 - (old_div * (192 - data->fan_preload[nr])
+		     + new_div / 2) / new_div;
+	data->fan_preload[nr] = SENSORS_LIMIT(tmp, 0, 191);
+	smsc47m1_write_value(client, SMSC47M1_REG_FAN_PRELOAD(nr),
+			     data->fan_preload[nr]);
+
+	return count;
+}
+
+static ssize_t set_fan_pwm(struct device *dev, const char *buf,
+		size_t count, int nr)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct smsc47m1_data *data = i2c_get_clientdata(client);
+
+	long val = simple_strtol(buf, NULL, 10);
+
+	if (val < 0 || val > 255)
+		return -EINVAL;
+
+	data->pwm[nr] &= 0x81; /* Preserve additional bits */
+	data->pwm[nr] |= PWM_TO_REG(val);
+
+	smsc47m1_write_value(client, SMSC47M1_REG_PWM(nr),
+			     data->pwm[nr]);
+	return count;
+}
+
+static ssize_t set_fan_pwm_en(struct device *dev, const char *buf,
+		size_t count, int nr)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct smsc47m1_data *data = i2c_get_clientdata(client);
+
+	long val = simple_strtol(buf, NULL, 10);
+	
+	if (val != 0 && val != 1)
+		return -EINVAL;
+
+	data->pwm[nr] &= 0xFE; /* preserve the other bits */
+	data->pwm[nr] |= !val;
+
+	smsc47m1_write_value(client, SMSC47M1_REG_PWM(nr),
+			     data->pwm[nr]);
+
+	return count;
+}
+
+#define fan_present(offset)						\
+static ssize_t get_fan##offset (struct device *dev, char *buf)		\
+{									\
+	return get_fan(dev, buf, 0x##offset - 1);			\
+}									\
+static ssize_t get_fan##offset##_min (struct device *dev, char *buf)	\
+{									\
+	return get_fan_min(dev, buf, 0x##offset - 1);			\
+}									\
+static ssize_t set_fan##offset##_min (struct device *dev,		\
+		const char *buf, size_t count)				\
+{									\
+	return set_fan_min(dev, buf, count, 0x##offset - 1);		\
+}									\
+static ssize_t get_fan##offset##_div (struct device *dev, char *buf)	\
+{									\
+	return get_fan_div(dev, buf, 0x##offset - 1);			\
+}									\
+static ssize_t set_fan##offset##_div (struct device *dev,		\
+		const char *buf, size_t count)				\
+{									\
+	return set_fan_div(dev, buf, count, 0x##offset - 1);		\
+}									\
+static ssize_t get_fan##offset##_pwm (struct device *dev, char *buf)	\
+{									\
+	return get_fan_pwm(dev, buf, 0x##offset - 1);			\
+}									\
+static ssize_t set_fan##offset##_pwm (struct device *dev,		\
+		const char *buf, size_t count)				\
+{									\
+	return set_fan_pwm(dev, buf, count, 0x##offset - 1);		\
+}									\
+static ssize_t get_fan##offset##_pwm_en (struct device *dev, char *buf)	\
+{									\
+	return get_fan_pwm_en(dev, buf, 0x##offset - 1);		\
+}									\
+static ssize_t set_fan##offset##_pwm_en (struct device *dev,		\
+		const char *buf, size_t count)				\
+{									\
+	return set_fan_pwm_en(dev, buf, count, 0x##offset - 1);		\
+}									\
+static DEVICE_ATTR(fan##offset##_input, S_IRUGO, get_fan##offset,	\
+		NULL);							\
+static DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,		\
+		get_fan##offset##_min, set_fan##offset##_min);		\
+static DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR,		\
+		get_fan##offset##_div, set_fan##offset##_div);		\
+static DEVICE_ATTR(fan##offset##_pwm, S_IRUGO | S_IWUSR,		\
+		get_fan##offset##_pwm, set_fan##offset##_pwm);		\
+static DEVICE_ATTR(fan##offset##_pwm_enable, S_IRUGO | S_IWUSR,		\
+		get_fan##offset##_pwm_en, set_fan##offset##_pwm_en);
+
+fan_present(1);
+fan_present(2);
+
+static DEVICE_ATTR(alarms, S_IRUGO, get_alarms, NULL);
+
+static int smsc47m1_attach_adapter(struct i2c_adapter *adapter)
+{
+	if (!(adapter->class & I2C_CLASS_HWMON))
+		return 0;
+	return i2c_detect(adapter, &addr_data, smsc47m1_detect);
+}
+
+static int smsc47m1_find(int *address)
+{
+	u8 val;
+
+	superio_enter();
+	val = superio_inb(SUPERIO_REG_DEVID);
+
+	/*
+	 * SMSC LPC47M10x/LPC47M13x (device id 0x59), LPC47M14x (device id
+	 * 0x5F) and LPC47B27x (device id 0x51) have fan control.
+	 * The LPC47M15x and LPC47M192 chips "with hardware monitoring block"
+	 * can do much more besides (device id 0x60, unsupported).
+	 */
+	if (val == 0x51)
+		printk(KERN_INFO "smsc47m1: Found SMSC47B27x\n");
+	else if (val == 0x59)
+		printk(KERN_INFO "smsc47m1: Found SMSC47M10x/SMSC47M13x\n");
+	else if (val == 0x5F)
+		printk(KERN_INFO "smsc47m1: Found SMSC47M14x\n");
+	else {
+		superio_exit();
+		return -ENODEV;
+	}
+
+	superio_select();
+	*address = (superio_inb(SUPERIO_REG_BASE) << 8)
+		 |  superio_inb(SUPERIO_REG_BASE + 1);
+	val = superio_inb(SUPERIO_REG_ACT);
+	if (*address == 0 || (val & 0x01) == 0) {
+		printk(KERN_INFO "smsc47m1: Device is disabled, will not use\n");
+		superio_exit();
+		return -ENODEV;
+	}
+
+	superio_exit();
+	return 0;
+}
+
+static int smsc47m1_detect(struct i2c_adapter *adapter, int address, int kind)
+{
+	struct i2c_client *new_client;
+	struct smsc47m1_data *data;
+	int err = 0;
+
+	if (!i2c_is_isa_adapter(adapter)) {
+		return 0;
+	}
+
+	if (!request_region(address, SMSC_EXTENT, "smsc47m1")) {
+		dev_err(&adapter->dev, "Region 0x%x already in use!\n", address);
+		return -EBUSY;
+	}
+
+	if (!(data = kmalloc(sizeof(struct smsc47m1_data), GFP_KERNEL))) {
+		err = -ENOMEM;
+		goto error_release;
+	}
+	memset(data, 0x00, sizeof(struct smsc47m1_data));
+
+	new_client = &data->client;
+	i2c_set_clientdata(new_client, data);
+	new_client->addr = address;
+	init_MUTEX(&data->lock);
+	new_client->adapter = adapter;
+	new_client->driver = &smsc47m1_driver;
+	new_client->flags = 0;
+
+	strlcpy(new_client->name, "smsc47m1", I2C_NAME_SIZE);
+
+	new_client->id = smsc47m1_id++;
+	init_MUTEX(&data->update_lock);
+
+	if ((err = i2c_attach_client(new_client)))
+		goto error_free;
+
+	/* Some values (fan min, clock dividers, pwm registers) may be
+	   needed before any update is triggered, so we better read them
+	   at least once here. We don't usually do it that way, but in
+	   this particular case, manually reading 5 registers out of 8
+	   doesn't make much sense and we're better using the existing
+	   function. */
+	smsc47m1_update_device(&new_client->dev, 1);
+
+	if ((smsc47m1_read_value(new_client, SMSC47M1_REG_TPIN(0)) & 0x05)
+	    == 0x05) {
+		device_create_file(&new_client->dev, &dev_attr_fan1_input);
+		device_create_file(&new_client->dev, &dev_attr_fan1_min);
+		device_create_file(&new_client->dev, &dev_attr_fan1_div);
+	} else
+		dev_dbg(&new_client->dev, "Fan 1 not enabled by hardware, "
+			"skipping\n");
+
+	if ((smsc47m1_read_value(new_client, SMSC47M1_REG_TPIN(1)) & 0x05)
+	    == 0x05) {
+		device_create_file(&new_client->dev, &dev_attr_fan2_input);
+		device_create_file(&new_client->dev, &dev_attr_fan2_min);
+		device_create_file(&new_client->dev, &dev_attr_fan2_div);
+	} else
+		dev_dbg(&new_client->dev, "Fan 2 not enabled by hardware, "
+			"skipping\n");
+
+	if ((smsc47m1_read_value(new_client, SMSC47M1_REG_PPIN(0)) & 0x05)
+	    == 0x04) {
+		device_create_file(&new_client->dev, &dev_attr_fan1_pwm);
+		device_create_file(&new_client->dev, &dev_attr_fan1_pwm_enable);
+	} else
+		dev_dbg(&new_client->dev, "PWM 1 not enabled by hardware, "
+			"skipping\n");
+	if ((smsc47m1_read_value(new_client, SMSC47M1_REG_PPIN(1)) & 0x05)
+	    == 0x04) {
+		device_create_file(&new_client->dev, &dev_attr_fan2_pwm);
+		device_create_file(&new_client->dev, &dev_attr_fan2_pwm_enable);
+	} else
+		dev_dbg(&new_client->dev, "PWM 2 not enabled by hardware, "
+			"skipping\n");
+
+	device_create_file(&new_client->dev, &dev_attr_alarms);
+
+	return 0;
+
+error_free:
+	kfree(new_client);
+error_release:
+	release_region(address, SMSC_EXTENT);
+	return err;
+}
+
+static int smsc47m1_detach_client(struct i2c_client *client)
+{
+	int err;
+
+	if ((err = i2c_detach_client(client))) {
+		dev_err(&client->dev, "Client deregistration failed, "
+			"client not detached.\n");
+		return err;
+	}
+
+	release_region(client->addr, SMSC_EXTENT);
+	kfree(i2c_get_clientdata(client));
+
+	return 0;
+}
+
+static int smsc47m1_read_value(struct i2c_client *client, u8 reg)
+{
+	int res;
+
+	down(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
+	res = inb_p(client->addr + reg);
+	up(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
+	return res;
+}
+
+static void smsc47m1_write_value(struct i2c_client *client, u8 reg, u8 value)
+{
+	down(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
+	outb_p(value, client->addr + reg);
+	up(&((struct smsc47m1_data *) i2c_get_clientdata(client))->lock);
+}
+
+static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
+		int init)
+{
+ 	struct i2c_client *client = to_i2c_client(dev);
+	struct smsc47m1_data *data = i2c_get_clientdata(client);
+
+	down(&data->update_lock);
+
+	if ((jiffies - data->last_updated > HZ + HZ / 2) ||
+	    (jiffies < data->last_updated) || init) {
+		int i;
+
+		for (i = 0; i < 2; i++) {
+			data->fan[i] = smsc47m1_read_value(client,
+				       SMSC47M1_REG_FAN(i));
+			data->fan_preload[i] = smsc47m1_read_value(client,
+					       SMSC47M1_REG_FAN_PRELOAD(i));
+			data->pwm[i] = smsc47m1_read_value(client,
+				       SMSC47M1_REG_PWM(i));
+		}
+
+		i = smsc47m1_read_value(client, SMSC47M1_REG_FANDIV);
+		data->fan_div[0] = (i >> 4) & 0x03;
+		data->fan_div[1] = i >> 6;
+
+		data->alarms = smsc47m1_read_value(client,
+			       SMSC47M1_REG_ALARM) >> 6;
+		/* Clear alarms if needed */
+		if (data->alarms)
+			smsc47m1_write_value(client, SMSC47M1_REG_ALARM, 0xC0);
+
+		data->last_updated = jiffies;
+	}
+
+	up(&data->update_lock);
+	return data;
+}
+
+static int __init sm_smsc47m1_init(void)
+{
+	if (smsc47m1_find(normal_isa)) {
+		return -ENODEV;
+	}
+
+	return i2c_add_driver(&smsc47m1_driver);
+}
+
+static void __exit sm_smsc47m1_exit(void)
+{
+	i2c_del_driver(&smsc47m1_driver);
+}
+
+MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123 at yahoo.com>");
+MODULE_DESCRIPTION("SMSC LPC47M1xx fan sensors driver");
+MODULE_LICENSE("GPL");
+
+module_init(sm_smsc47m1_init);
+module_exit(sm_smsc47m1_exit);


-- 
Jean "Khali" Delvare
http://khali.linux-fr.org/



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