/*

   * smsc47m1.c - Part of lm_sensors, Linux kernel modules
   *		for hardware monitoring
   *
   * Supports the SMSC LPC47B27x, LPC47M10x, LPC47M112, LPC47M13x,
   * LPC47M14x, LPC47M15x, LPC47M192, LPC47M292 and LPC47M997
   * Super-I/O chips.
   *
   * Copyright (C) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>

   * Copyright (C) 2004-2007 Jean Delvare <jdelvare@suse.de>

   * Ported to Linux 2.6 by Gabriele Gorla <gorlik@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.
   */

  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

  #include <linux/module.h>
  #include <linux/slab.h>
  #include <linux/ioport.h>
  #include <linux/jiffies.h>

  #include <linux/platform_device.h>

  #include <linux/hwmon.h>

  #include <linux/hwmon-sysfs.h>

  #include <linux/err.h>

  #include <linux/init.h>

  #include <linux/mutex.h>

  #include <linux/sysfs.h>

  #include <linux/acpi.h>

  #include <linux/io.h>

  static unsigned short force_id;
  module_param(force_id, ushort, 0);
  MODULE_PARM_DESC(force_id, "Override the detected device ID");

  static struct platform_device *pdev;
  
  #define DRVNAME "smsc47m1"

  enum chips { smsc47m1, smsc47m2 };

  
  /* 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

  #define SUPERIO_REG_DEVREV	0x21

  
  /* 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_FANDIV		0x58

  
  static const u8 SMSC47M1_REG_FAN[3]		= { 0x59, 0x5a, 0x6b };
  static const u8 SMSC47M1_REG_FAN_PRELOAD[3]	= { 0x5b, 0x5c, 0x6c };
  static const u8 SMSC47M1_REG_PWM[3]		= { 0x56, 0x57, 0x69 };
  
  #define SMSC47M2_REG_ALARM6		0x09
  #define SMSC47M2_REG_TPIN1		0x38
  #define SMSC47M2_REG_TPIN2		0x37
  #define SMSC47M2_REG_TPIN3		0x2d
  #define SMSC47M2_REG_PPIN3		0x2c
  #define SMSC47M2_REG_FANDIV3		0x6a

  #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 {

  	unsigned short addr;
  	const char *name;

  	enum chips type;

  	struct device *hwmon_dev;

  	struct mutex update_lock;

  	unsigned long last_updated;	/* In jiffies */

  	u8 fan[3];		/* Register value */
  	u8 fan_preload[3];	/* Register value */
  	u8 fan_div[3];		/* Register encoding, shifted right */

  	u8 alarms;		/* Register encoding */

  	u8 pwm[3];		/* Register value (bit 0 is disable) */

  };

  struct smsc47m1_sio_data {
  	enum chips type;

  	u8 activate;		/* Remember initial device state */

  };

  static inline int smsc47m1_read_value(struct smsc47m1_data *data, u8 reg)

  {

  	return inb_p(data->addr + reg);

  }

  static inline void smsc47m1_write_value(struct smsc47m1_data *data, u8 reg,

  		u8 value)
  {

  	outb_p(value, data->addr + reg);

  }

  static struct smsc47m1_data *smsc47m1_update_device(struct device *dev,
  		int init)
  {
  	struct smsc47m1_data *data = dev_get_drvdata(dev);
  
  	mutex_lock(&data->update_lock);
  
  	if (time_after(jiffies, data->last_updated + HZ + HZ / 2) || init) {
  		int i, fan_nr;
  		fan_nr = data->type == smsc47m2 ? 3 : 2;
  
  		for (i = 0; i < fan_nr; i++) {
  			data->fan[i] = smsc47m1_read_value(data,
  				       SMSC47M1_REG_FAN[i]);
  			data->fan_preload[i] = smsc47m1_read_value(data,
  					       SMSC47M1_REG_FAN_PRELOAD[i]);
  			data->pwm[i] = smsc47m1_read_value(data,
  				       SMSC47M1_REG_PWM[i]);
  		}
  
  		i = smsc47m1_read_value(data, SMSC47M1_REG_FANDIV);
  		data->fan_div[0] = (i >> 4) & 0x03;
  		data->fan_div[1] = i >> 6;
  
  		data->alarms = smsc47m1_read_value(data,
  			       SMSC47M1_REG_ALARM) >> 6;
  		/* Clear alarms if needed */
  		if (data->alarms)
  			smsc47m1_write_value(data, SMSC47M1_REG_ALARM, 0xC0);
  
  		if (fan_nr >= 3) {
  			data->fan_div[2] = (smsc47m1_read_value(data,
  					    SMSC47M2_REG_FANDIV3) >> 4) & 0x03;
  			data->alarms |= (smsc47m1_read_value(data,
  					 SMSC47M2_REG_ALARM6) & 0x40) >> 4;
  			/* Clear alarm if needed */
  			if (data->alarms & 0x04)
  				smsc47m1_write_value(data,
  						     SMSC47M2_REG_ALARM6,
  						     0x40);
  		}
  
  		data->last_updated = jiffies;
  	}
  
  	mutex_unlock(&data->update_lock);
  	return data;
  }

  static ssize_t get_fan(struct device *dev, struct device_attribute
  		       *devattr, char *buf)

  {

  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

  	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);

  	int nr = attr->index;

  	/*
  	 * 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
  ", rpm);
  }

  static ssize_t get_fan_min(struct device *dev, struct device_attribute
  			   *devattr, char *buf)

  {

  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

  	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);

  	int nr = attr->index;

  	int rpm = MIN_FROM_REG(data->fan_preload[nr],
  			       DIV_FROM_REG(data->fan_div[nr]));
  	return sprintf(buf, "%d
  ", rpm);
  }

  static ssize_t get_fan_div(struct device *dev, struct device_attribute
  			   *devattr, char *buf)

  {

  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

  	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);

  	return sprintf(buf, "%d
  ", DIV_FROM_REG(data->fan_div[attr->index]));

  }

  static ssize_t get_fan_alarm(struct device *dev, struct device_attribute
  			     *devattr, char *buf)
  {
  	int bitnr = to_sensor_dev_attr(devattr)->index;
  	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
  	return sprintf(buf, "%u
  ", (data->alarms >> bitnr) & 1);
  }

  static ssize_t get_pwm(struct device *dev, struct device_attribute
  		       *devattr, char *buf)

  {

  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

  	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);

  	return sprintf(buf, "%d
  ", PWM_FROM_REG(data->pwm[attr->index]));

  }

  static ssize_t get_pwm_en(struct device *dev, struct device_attribute
  			  *devattr, char *buf)

  {

  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

  	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);

  	return sprintf(buf, "%d
  ", PWM_EN_FROM_REG(data->pwm[attr->index]));

  }

  static ssize_t get_alarms(struct device *dev, struct device_attribute
  			  *devattr, char *buf)

  {
  	struct smsc47m1_data *data = smsc47m1_update_device(dev, 0);
  	return sprintf(buf, "%d
  ", data->alarms);
  }

  static ssize_t set_fan_min(struct device *dev, struct device_attribute
  			   *devattr, const char *buf, size_t count)

  {

  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

  	struct smsc47m1_data *data = dev_get_drvdata(dev);

  	int nr = attr->index;

  	long rpmdiv;
  	long val;
  	int err;
  
  	err = kstrtol(buf, 10, &val);
  	if (err)
  		return err;

  	mutex_lock(&data->update_lock);

  	rpmdiv = val * DIV_FROM_REG(data->fan_div[nr]);
  
  	if (983040 > 192 * rpmdiv || 2 * rpmdiv > 983040) {

  		mutex_unlock(&data->update_lock);

  		return -EINVAL;
  	}
  
  	data->fan_preload[nr] = 192 - ((983040 + rpmdiv / 2) / rpmdiv);

  	smsc47m1_write_value(data, SMSC47M1_REG_FAN_PRELOAD[nr],

  			     data->fan_preload[nr]);

  	mutex_unlock(&data->update_lock);

  
  	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 surprise; the user doesn't expect the fan minimum to change just
   * because the divider changed.
   */

  static ssize_t set_fan_div(struct device *dev, struct device_attribute
  			   *devattr, const char *buf, size_t count)

  {

  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

  	struct smsc47m1_data *data = dev_get_drvdata(dev);

  	int nr = attr->index;

  	long new_div;
  	int err;
  	long tmp;

  	u8 old_div = DIV_FROM_REG(data->fan_div[nr]);

  	err = kstrtol(buf, 10, &new_div);
  	if (err)
  		return err;

  	if (new_div == old_div) /* No change */
  		return count;

  	mutex_lock(&data->update_lock);

  	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:

  		mutex_unlock(&data->update_lock);

  		return -EINVAL;
  	}

  	switch (nr) {
  	case 0:
  	case 1:

  		tmp = smsc47m1_read_value(data, SMSC47M1_REG_FANDIV)

  		      & ~(0x03 << (4 + 2 * nr));
  		tmp |= data->fan_div[nr] << (4 + 2 * nr);

  		smsc47m1_write_value(data, SMSC47M1_REG_FANDIV, tmp);

  		break;
  	case 2:

  		tmp = smsc47m1_read_value(data, SMSC47M2_REG_FANDIV3) & 0xCF;

  		tmp |= data->fan_div[2] << 4;

  		smsc47m1_write_value(data, SMSC47M2_REG_FANDIV3, tmp);

  		break;
  	}

  
  	/* Preserve fan min */
  	tmp = 192 - (old_div * (192 - data->fan_preload[nr])
  		     + new_div / 2) / new_div;

  	data->fan_preload[nr] = clamp_val(tmp, 0, 191);

  	smsc47m1_write_value(data, SMSC47M1_REG_FAN_PRELOAD[nr],

  			     data->fan_preload[nr]);

  	mutex_unlock(&data->update_lock);

  
  	return count;
  }

  static ssize_t set_pwm(struct device *dev, struct device_attribute
  		       *devattr, const char *buf, size_t count)

  {

  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

  	struct smsc47m1_data *data = dev_get_drvdata(dev);

  	int nr = attr->index;

  	long val;
  	int err;
  
  	err = kstrtol(buf, 10, &val);
  	if (err)
  		return err;

  
  	if (val < 0 || val > 255)
  		return -EINVAL;

  	mutex_lock(&data->update_lock);

  	data->pwm[nr] &= 0x81; /* Preserve additional bits */
  	data->pwm[nr] |= PWM_TO_REG(val);

  	smsc47m1_write_value(data, SMSC47M1_REG_PWM[nr],

  			     data->pwm[nr]);

  	mutex_unlock(&data->update_lock);

  
  	return count;
  }

  static ssize_t set_pwm_en(struct device *dev, struct device_attribute
  			  *devattr, const char *buf, size_t count)

  {

  	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

  	struct smsc47m1_data *data = dev_get_drvdata(dev);

  	int nr = attr->index;

  	unsigned long val;
  	int err;
  
  	err = kstrtoul(buf, 10, &val);
  	if (err)
  		return err;
  
  	if (val > 1)

  		return -EINVAL;

  	mutex_lock(&data->update_lock);

  	data->pwm[nr] &= 0xFE; /* preserve the other bits */
  	data->pwm[nr] |= !val;

  	smsc47m1_write_value(data, SMSC47M1_REG_PWM[nr],

  			     data->pwm[nr]);

  	mutex_unlock(&data->update_lock);

  
  	return count;
  }
  
  #define fan_present(offset)						\

  static SENSOR_DEVICE_ATTR(fan##offset##_input, S_IRUGO, get_fan,	\
  		NULL, offset - 1);					\
  static SENSOR_DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,		\
  		get_fan_min, set_fan_min, offset - 1);			\
  static SENSOR_DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR,		\
  		get_fan_div, set_fan_div, offset - 1);			\

  static SENSOR_DEVICE_ATTR(fan##offset##_alarm, S_IRUGO, get_fan_alarm,	\
  		NULL, offset - 1);					\

  static SENSOR_DEVICE_ATTR(pwm##offset, S_IRUGO | S_IWUSR,		\
  		get_pwm, set_pwm, offset - 1);				\
  static SENSOR_DEVICE_ATTR(pwm##offset##_enable, S_IRUGO | S_IWUSR,	\
  		get_pwm_en, set_pwm_en, offset - 1)

  
  fan_present(1);
  fan_present(2);

  fan_present(3);

  
  static DEVICE_ATTR(alarms, S_IRUGO, get_alarms, NULL);

  static ssize_t show_name(struct device *dev, struct device_attribute
  			 *devattr, char *buf)
  {
  	struct smsc47m1_data *data = dev_get_drvdata(dev);
  
  	return sprintf(buf, "%s
  ", data->name);
  }
  static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);

  static struct attribute *smsc47m1_attributes_fan1[] = {

  	&sensor_dev_attr_fan1_input.dev_attr.attr,
  	&sensor_dev_attr_fan1_min.dev_attr.attr,
  	&sensor_dev_attr_fan1_div.dev_attr.attr,

  	&sensor_dev_attr_fan1_alarm.dev_attr.attr,

  	NULL
  };
  
  static const struct attribute_group smsc47m1_group_fan1 = {
  	.attrs = smsc47m1_attributes_fan1,
  };
  
  static struct attribute *smsc47m1_attributes_fan2[] = {

  	&sensor_dev_attr_fan2_input.dev_attr.attr,
  	&sensor_dev_attr_fan2_min.dev_attr.attr,
  	&sensor_dev_attr_fan2_div.dev_attr.attr,

  	&sensor_dev_attr_fan2_alarm.dev_attr.attr,

  	NULL
  };
  
  static const struct attribute_group smsc47m1_group_fan2 = {
  	.attrs = smsc47m1_attributes_fan2,
  };
  
  static struct attribute *smsc47m1_attributes_fan3[] = {

  	&sensor_dev_attr_fan3_input.dev_attr.attr,
  	&sensor_dev_attr_fan3_min.dev_attr.attr,
  	&sensor_dev_attr_fan3_div.dev_attr.attr,

  	&sensor_dev_attr_fan3_alarm.dev_attr.attr,

  	NULL
  };

  static const struct attribute_group smsc47m1_group_fan3 = {
  	.attrs = smsc47m1_attributes_fan3,
  };
  
  static struct attribute *smsc47m1_attributes_pwm1[] = {

  	&sensor_dev_attr_pwm1.dev_attr.attr,
  	&sensor_dev_attr_pwm1_enable.dev_attr.attr,

  	NULL
  };
  
  static const struct attribute_group smsc47m1_group_pwm1 = {
  	.attrs = smsc47m1_attributes_pwm1,
  };
  
  static struct attribute *smsc47m1_attributes_pwm2[] = {

  	&sensor_dev_attr_pwm2.dev_attr.attr,
  	&sensor_dev_attr_pwm2_enable.dev_attr.attr,

  	NULL
  };
  
  static const struct attribute_group smsc47m1_group_pwm2 = {
  	.attrs = smsc47m1_attributes_pwm2,
  };
  
  static struct attribute *smsc47m1_attributes_pwm3[] = {

  	&sensor_dev_attr_pwm3.dev_attr.attr,
  	&sensor_dev_attr_pwm3_enable.dev_attr.attr,

  	NULL
  };

  static const struct attribute_group smsc47m1_group_pwm3 = {
  	.attrs = smsc47m1_attributes_pwm3,
  };
  
  static struct attribute *smsc47m1_attributes[] = {

  	&dev_attr_alarms.attr,

  	&dev_attr_name.attr,

  	NULL
  };
  
  static const struct attribute_group smsc47m1_group = {
  	.attrs = smsc47m1_attributes,
  };

  static int __init smsc47m1_find(struct smsc47m1_sio_data *sio_data)

  {
  	u8 val;

  	unsigned short addr;

  
  	superio_enter();

  	val = force_id ? force_id : superio_inb(SUPERIO_REG_DEVID);

  
  	/*

  	 * SMSC LPC47M10x/LPC47M112/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).

  	 * The LPC47M997 is undocumented, but seems to be compatible with
  	 * the LPC47M192, and has the same device id.

  	 * The LPC47M292 (device id 0x6B) is somewhat compatible, but it
  	 * supports a 3rd fan, and the pin configuration registers are
  	 * unfortunately different.

  	 * The LPC47M233 has the same device id (0x6B) but is not compatible.
  	 * We check the high bit of the device revision register to
  	 * differentiate them.

  	 */

  	switch (val) {

  	case 0x51:

  		pr_info("Found SMSC LPC47B27x
  ");

  		sio_data->type = smsc47m1;

  		break;
  	case 0x59:

  		pr_info("Found SMSC LPC47M10x/LPC47M112/LPC47M13x
  ");

  		sio_data->type = smsc47m1;

  		break;
  	case 0x5F:

  		pr_info("Found SMSC LPC47M14x
  ");

  		sio_data->type = smsc47m1;

  		break;
  	case 0x60:

  		pr_info("Found SMSC LPC47M15x/LPC47M192/LPC47M997
  ");

  		sio_data->type = smsc47m1;

  		break;
  	case 0x6B:

  		if (superio_inb(SUPERIO_REG_DEVREV) & 0x80) {

  			pr_debug("Found SMSC LPC47M233, unsupported
  ");

  			superio_exit();
  			return -ENODEV;
  		}

  		pr_info("Found SMSC LPC47M292
  ");

  		sio_data->type = smsc47m2;

  		break;
  	default:

  		superio_exit();
  		return -ENODEV;
  	}
  
  	superio_select();

  	addr = (superio_inb(SUPERIO_REG_BASE) << 8)

  	      |  superio_inb(SUPERIO_REG_BASE + 1);

  	if (addr == 0) {

  		pr_info("Device address not set, will not use
  ");

  		superio_exit();
  		return -ENODEV;
  	}

  	/*
  	 * Enable only if address is set (needed at least on the
  	 * Compaq Presario S4000NX)
  	 */

  	sio_data->activate = superio_inb(SUPERIO_REG_ACT);
  	if ((sio_data->activate & 0x01) == 0) {

  		pr_info("Enabling device
  ");

  		superio_outb(SUPERIO_REG_ACT, sio_data->activate | 0x01);
  	}

  	superio_exit();

  	return addr;

  }

  /* Restore device to its initial state */

  static void smsc47m1_restore(const struct smsc47m1_sio_data *sio_data)

  {
  	if ((sio_data->activate & 0x01) == 0) {
  		superio_enter();
  		superio_select();

  		pr_info("Disabling device
  ");

  		superio_outb(SUPERIO_REG_ACT, sio_data->activate);
  
  		superio_exit();
  	}
  }

  #define CHECK		1
  #define REQUEST		2

  
  /*
   * This function can be used to:
   *  - test for resource conflicts with ACPI
   *  - request the resources

   * We only allocate the I/O ports we really need, to minimize the risk of
   * conflicts with ACPI or with other drivers.
   */

  static int __init smsc47m1_handle_resources(unsigned short address,
  					    enum chips type, int action,
  					    struct device *dev)

  {
  	static const u8 ports_m1[] = {
  		/* register, region length */
  		0x04, 1,
  		0x33, 4,
  		0x56, 7,
  	};
  
  	static const u8 ports_m2[] = {
  		/* register, region length */
  		0x04, 1,
  		0x09, 1,
  		0x2c, 2,
  		0x35, 4,
  		0x56, 7,
  		0x69, 4,
  	};
  
  	int i, ports_size, err;
  	const u8 *ports;
  
  	switch (type) {
  	case smsc47m1:
  	default:
  		ports = ports_m1;
  		ports_size = ARRAY_SIZE(ports_m1);
  		break;
  	case smsc47m2:
  		ports = ports_m2;
  		ports_size = ARRAY_SIZE(ports_m2);
  		break;
  	}
  
  	for (i = 0; i + 1 < ports_size; i += 2) {
  		unsigned short start = address + ports[i];
  		unsigned short len = ports[i + 1];
  
  		switch (action) {
  		case CHECK:
  			/* Only check for conflicts */
  			err = acpi_check_region(start, len, DRVNAME);
  			if (err)
  				return err;
  			break;
  		case REQUEST:
  			/* Request the resources */

  			if (!devm_request_region(dev, start, len, DRVNAME)) {
  				dev_err(dev,
  					"Region 0x%hx-0x%hx already in use!
  ",
  					start, start + len);

  				return -EBUSY;
  			}
  			break;

  		}
  	}
  
  	return 0;
  }

  static void smsc47m1_remove_files(struct device *dev)
  {
  	sysfs_remove_group(&dev->kobj, &smsc47m1_group);
  	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan1);
  	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan2);
  	sysfs_remove_group(&dev->kobj, &smsc47m1_group_fan3);
  	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm1);
  	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm2);
  	sysfs_remove_group(&dev->kobj, &smsc47m1_group_pwm3);
  }

  static int __init smsc47m1_probe(struct platform_device *pdev)

  {

  	struct device *dev = &pdev->dev;

  	struct smsc47m1_sio_data *sio_data = dev_get_platdata(dev);

  	struct smsc47m1_data *data;

  	struct resource *res;

  	int err;

  	int fan1, fan2, fan3, pwm1, pwm2, pwm3;

  	static const char * const names[] = {

  		"smsc47m1",
  		"smsc47m2",
  	};
  
  	res = platform_get_resource(pdev, IORESOURCE_IO, 0);

  	err = smsc47m1_handle_resources(res->start, sio_data->type,
  					REQUEST, dev);
  	if (err < 0)
  		return err;

  	data = devm_kzalloc(dev, sizeof(struct smsc47m1_data), GFP_KERNEL);
  	if (!data)
  		return -ENOMEM;

  	data->addr = res->start;
  	data->type = sio_data->type;
  	data->name = names[sio_data->type];

  	mutex_init(&data->update_lock);

  	platform_set_drvdata(pdev, data);

  	/*
  	 * If no function is properly configured, there's no point in
  	 * actually registering the chip.
  	 */

  	pwm1 = (smsc47m1_read_value(data, SMSC47M1_REG_PPIN(0)) & 0x05)

  	       == 0x04;

  	pwm2 = (smsc47m1_read_value(data, SMSC47M1_REG_PPIN(1)) & 0x05)

  	       == 0x04;

  	if (data->type == smsc47m2) {

  		fan1 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN1)

  			& 0x0d) == 0x09;

  		fan2 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN2)

  			& 0x0d) == 0x09;

  		fan3 = (smsc47m1_read_value(data, SMSC47M2_REG_TPIN3)

  			& 0x0d) == 0x0d;

  		pwm3 = (smsc47m1_read_value(data, SMSC47M2_REG_PPIN3)

  			& 0x0d) == 0x08;
  	} else {

  		fan1 = (smsc47m1_read_value(data, SMSC47M1_REG_TPIN(0))

  			& 0x05) == 0x05;

  		fan2 = (smsc47m1_read_value(data, SMSC47M1_REG_TPIN(1))

  			& 0x05) == 0x05;
  		fan3 = 0;
  		pwm3 = 0;
  	}
  	if (!(fan1 || fan2 || fan3 || pwm1 || pwm2 || pwm3)) {

  		dev_warn(dev, "Device not configured, will not use
  ");

  		return -ENODEV;

  	}

  	/*
  	 * 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(dev, 1);

  	/* Register sysfs hooks */

  	if (fan1) {

  		err = sysfs_create_group(&dev->kobj,
  					 &smsc47m1_group_fan1);
  		if (err)

  			goto error_remove_files;

  	} else

  		dev_dbg(dev, "Fan 1 not enabled by hardware, skipping
  ");

  
  	if (fan2) {

  		err = sysfs_create_group(&dev->kobj,
  					 &smsc47m1_group_fan2);
  		if (err)

  			goto error_remove_files;

  	} else

  		dev_dbg(dev, "Fan 2 not enabled by hardware, skipping
  ");

  	if (fan3) {

  		err = sysfs_create_group(&dev->kobj,
  					 &smsc47m1_group_fan3);
  		if (err)

  			goto error_remove_files;

  	} else if (data->type == smsc47m2)

  		dev_dbg(dev, "Fan 3 not enabled by hardware, skipping
  ");

  	if (pwm1) {

  		err = sysfs_create_group(&dev->kobj,
  					 &smsc47m1_group_pwm1);
  		if (err)

  			goto error_remove_files;

  	} else

  		dev_dbg(dev, "PWM 1 not enabled by hardware, skipping
  ");

  	if (pwm2) {

  		err = sysfs_create_group(&dev->kobj,
  					 &smsc47m1_group_pwm2);
  		if (err)

  			goto error_remove_files;

  	} else

  		dev_dbg(dev, "PWM 2 not enabled by hardware, skipping
  ");

  	if (pwm3) {

  		err = sysfs_create_group(&dev->kobj,
  					 &smsc47m1_group_pwm3);
  		if (err)

  			goto error_remove_files;

  	} else if (data->type == smsc47m2)

  		dev_dbg(dev, "PWM 3 not enabled by hardware, skipping
  ");

  	err = sysfs_create_group(&dev->kobj, &smsc47m1_group);
  	if (err)

  		goto error_remove_files;

  	data->hwmon_dev = hwmon_device_register(dev);
  	if (IS_ERR(data->hwmon_dev)) {
  		err = PTR_ERR(data->hwmon_dev);

  		goto error_remove_files;
  	}

  
  	return 0;

  error_remove_files:

  	smsc47m1_remove_files(dev);

  	return err;
  }

  static int __exit smsc47m1_remove(struct platform_device *pdev)

  {

  	struct smsc47m1_data *data = platform_get_drvdata(pdev);

  	hwmon_device_unregister(data->hwmon_dev);

  	smsc47m1_remove_files(&pdev->dev);

  	return 0;
  }

  static struct platform_driver smsc47m1_driver = {
  	.driver = {

  		.name	= DRVNAME,
  	},
  	.remove		= __exit_p(smsc47m1_remove),
  };

  static int __init smsc47m1_device_add(unsigned short address,
  				      const struct smsc47m1_sio_data *sio_data)
  {
  	struct resource res = {
  		.start	= address,
  		.end	= address + SMSC_EXTENT - 1,
  		.name	= DRVNAME,
  		.flags	= IORESOURCE_IO,
  	};
  	int err;

  	err = smsc47m1_handle_resources(address, sio_data->type, CHECK, NULL);

  	if (err)
  		goto exit;

  	pdev = platform_device_alloc(DRVNAME, address);
  	if (!pdev) {
  		err = -ENOMEM;

  		pr_err("Device allocation failed
  ");

  		goto exit;
  	}
  
  	err = platform_device_add_resources(pdev, &res, 1);
  	if (err) {

  		pr_err("Device resource addition failed (%d)
  ", err);

  		goto exit_device_put;
  	}

  	err = platform_device_add_data(pdev, sio_data,
  				       sizeof(struct smsc47m1_sio_data));
  	if (err) {

  		pr_err("Platform data allocation failed
  ");

  		goto exit_device_put;
  	}

  
  	err = platform_device_add(pdev);
  	if (err) {

  		pr_err("Device addition failed (%d)
  ", err);

  		goto exit_device_put;
  	}
  
  	return 0;
  
  exit_device_put:
  	platform_device_put(pdev);
  exit:
  	return err;
  }

  static int __init sm_smsc47m1_init(void)
  {

  	int err;
  	unsigned short address;
  	struct smsc47m1_sio_data sio_data;

  	err = smsc47m1_find(&sio_data);
  	if (err < 0)
  		return err;
  	address = err;

  	/* Sets global pdev as a side effect */
  	err = smsc47m1_device_add(address, &sio_data);

  	if (err)

  		return err;

  	err = platform_driver_probe(&smsc47m1_driver, smsc47m1_probe);

  	if (err)

  		goto exit_device;

  
  	return 0;

  exit_device:
  	platform_device_unregister(pdev);

  	smsc47m1_restore(&sio_data);

  	return err;

  }
  
  static void __exit sm_smsc47m1_exit(void)
  {

  	platform_driver_unregister(&smsc47m1_driver);

  	smsc47m1_restore(dev_get_platdata(&pdev->dev));

  	platform_device_unregister(pdev);

  }
  
  MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>");
  MODULE_DESCRIPTION("SMSC LPC47M1xx fan sensors driver");
  MODULE_LICENSE("GPL");
  
  module_init(sm_smsc47m1_init);
  module_exit(sm_smsc47m1_exit);