/*
      thmc50.c - Part of lm_sensors, Linux kernel modules for hardware
               monitoring
      Copyright (C) 2007 Krzysztof Helt <krzysztof.h1@wp.pl>
      Based on 2.4 driver by Frodo Looijaard <frodol@dds.nl> and
      Philip Edelbrock <phil@netroedge.com>
  
      This program is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published by
      the Free Software Foundation; either version 2 of the License, or
      (at your option) any later version.
  
      This program is distributed in the hope that it will be useful,
      but WITHOUT ANY WARRANTY; without even the implied warranty of
      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      GNU General Public License for more details.
  
      You should have received a copy of the GNU General Public License
      along with this program; if not, write to the Free Software
      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
  
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/slab.h>
  #include <linux/i2c.h>
  #include <linux/hwmon.h>
  #include <linux/hwmon-sysfs.h>
  #include <linux/err.h>
  #include <linux/mutex.h>
  
  MODULE_LICENSE("GPL");
  
  /* Addresses to scan */

  static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, I2C_CLIENT_END };

  
  /* Insmod parameters */

  enum chips { thmc50, adm1022 };

  
  static unsigned short adm1022_temp3[16];
  static unsigned int adm1022_temp3_num;
  module_param_array(adm1022_temp3, ushort, &adm1022_temp3_num, 0);
  MODULE_PARM_DESC(adm1022_temp3, "List of adapter,address pairs "

  			"to enable 3rd temperature (ADM1022 only)");
  
  /* Many THMC50 constants specified below */
  
  /* The THMC50 registers */
  #define THMC50_REG_CONF				0x40
  #define THMC50_REG_COMPANY_ID			0x3E
  #define THMC50_REG_DIE_CODE			0x3F
  #define THMC50_REG_ANALOG_OUT			0x19

  /*

   * The mirror status register cannot be used as
   * reading it does not clear alarms.

   */

  #define THMC50_REG_INTR				0x41

  static const u8 THMC50_REG_TEMP[] = { 0x27, 0x26, 0x20 };
  static const u8 THMC50_REG_TEMP_MIN[] = { 0x3A, 0x38, 0x2C };
  static const u8 THMC50_REG_TEMP_MAX[] = { 0x39, 0x37, 0x2B };

  static const u8 THMC50_REG_TEMP_CRITICAL[] = { 0x13, 0x14, 0x14 };
  static const u8 THMC50_REG_TEMP_DEFAULT[] = { 0x17, 0x18, 0x18 };

  
  #define THMC50_REG_CONF_nFANOFF			0x20

  #define THMC50_REG_CONF_PROGRAMMED		0x08

  
  /* Each client has this additional data */
  struct thmc50_data {

  	struct device *hwmon_dev;

  
  	struct mutex update_lock;
  	enum chips type;
  	unsigned long last_updated;	/* In jiffies */
  	char has_temp3;		/* !=0 if it is ADM1022 in temp3 mode */
  	char valid;		/* !=0 if following fields are valid */
  
  	/* Register values */
  	s8 temp_input[3];
  	s8 temp_max[3];
  	s8 temp_min[3];

  	s8 temp_critical[3];

  	u8 analog_out;

  	u8 alarms;

  };

  static int thmc50_detect(struct i2c_client *client,

  			 struct i2c_board_info *info);
  static int thmc50_probe(struct i2c_client *client,
  			const struct i2c_device_id *id);
  static int thmc50_remove(struct i2c_client *client);

  static void thmc50_init_client(struct i2c_client *client);
  static struct thmc50_data *thmc50_update_device(struct device *dev);

  static const struct i2c_device_id thmc50_id[] = {
  	{ "adm1022", adm1022 },
  	{ "thmc50", thmc50 },
  	{ }
  };
  MODULE_DEVICE_TABLE(i2c, thmc50_id);

  static struct i2c_driver thmc50_driver = {

  	.class = I2C_CLASS_HWMON,

  	.driver = {
  		.name = "thmc50",
  	},

  	.probe = thmc50_probe,
  	.remove = thmc50_remove,
  	.id_table = thmc50_id,
  	.detect = thmc50_detect,

  	.address_list = normal_i2c,

  };
  
  static ssize_t show_analog_out(struct device *dev,
  			       struct device_attribute *attr, char *buf)
  {
  	struct thmc50_data *data = thmc50_update_device(dev);
  	return sprintf(buf, "%d
  ", data->analog_out);
  }
  
  static ssize_t set_analog_out(struct device *dev,
  			      struct device_attribute *attr,
  			      const char *buf, size_t count)
  {
  	struct i2c_client *client = to_i2c_client(dev);
  	struct thmc50_data *data = i2c_get_clientdata(client);
  	int tmp = simple_strtoul(buf, NULL, 10);
  	int config;
  
  	mutex_lock(&data->update_lock);
  	data->analog_out = SENSORS_LIMIT(tmp, 0, 255);
  	i2c_smbus_write_byte_data(client, THMC50_REG_ANALOG_OUT,
  				  data->analog_out);
  
  	config = i2c_smbus_read_byte_data(client, THMC50_REG_CONF);
  	if (data->analog_out == 0)
  		config &= ~THMC50_REG_CONF_nFANOFF;
  	else
  		config |= THMC50_REG_CONF_nFANOFF;
  	i2c_smbus_write_byte_data(client, THMC50_REG_CONF, config);
  
  	mutex_unlock(&data->update_lock);
  	return count;
  }
  
  /* There is only one PWM mode = DC */
  static ssize_t show_pwm_mode(struct device *dev, struct device_attribute *attr,
  			     char *buf)
  {
  	return sprintf(buf, "0
  ");
  }
  
  /* Temperatures */
  static ssize_t show_temp(struct device *dev, struct device_attribute *attr,
  			 char *buf)
  {
  	int nr = to_sensor_dev_attr(attr)->index;
  	struct thmc50_data *data = thmc50_update_device(dev);
  	return sprintf(buf, "%d
  ", data->temp_input[nr] * 1000);
  }
  
  static ssize_t show_temp_min(struct device *dev, struct device_attribute *attr,
  			     char *buf)
  {
  	int nr = to_sensor_dev_attr(attr)->index;
  	struct thmc50_data *data = thmc50_update_device(dev);
  	return sprintf(buf, "%d
  ", data->temp_min[nr] * 1000);
  }
  
  static ssize_t set_temp_min(struct device *dev, struct device_attribute *attr,
  			    const char *buf, size_t count)
  {
  	int nr = to_sensor_dev_attr(attr)->index;
  	struct i2c_client *client = to_i2c_client(dev);
  	struct thmc50_data *data = i2c_get_clientdata(client);
  	int val = simple_strtol(buf, NULL, 10);
  
  	mutex_lock(&data->update_lock);
  	data->temp_min[nr] = SENSORS_LIMIT(val / 1000, -128, 127);
  	i2c_smbus_write_byte_data(client, THMC50_REG_TEMP_MIN[nr],
  				  data->temp_min[nr]);
  	mutex_unlock(&data->update_lock);
  	return count;
  }
  
  static ssize_t show_temp_max(struct device *dev, struct device_attribute *attr,
  			     char *buf)
  {
  	int nr = to_sensor_dev_attr(attr)->index;
  	struct thmc50_data *data = thmc50_update_device(dev);
  	return sprintf(buf, "%d
  ", data->temp_max[nr] * 1000);
  }
  
  static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
  			    const char *buf, size_t count)
  {
  	int nr = to_sensor_dev_attr(attr)->index;
  	struct i2c_client *client = to_i2c_client(dev);
  	struct thmc50_data *data = i2c_get_clientdata(client);
  	int val = simple_strtol(buf, NULL, 10);
  
  	mutex_lock(&data->update_lock);
  	data->temp_max[nr] = SENSORS_LIMIT(val / 1000, -128, 127);
  	i2c_smbus_write_byte_data(client, THMC50_REG_TEMP_MAX[nr],
  				  data->temp_max[nr]);
  	mutex_unlock(&data->update_lock);
  	return count;
  }

  static ssize_t show_temp_critical(struct device *dev,
  				  struct device_attribute *attr,
  				  char *buf)
  {
  	int nr = to_sensor_dev_attr(attr)->index;
  	struct thmc50_data *data = thmc50_update_device(dev);
  	return sprintf(buf, "%d
  ", data->temp_critical[nr] * 1000);
  }

  static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
  			  char *buf)
  {
  	int index = to_sensor_dev_attr(attr)->index;
  	struct thmc50_data *data = thmc50_update_device(dev);
  
  	return sprintf(buf, "%u
  ", (data->alarms >> index) & 1);
  }

  #define temp_reg(offset)						\
  static SENSOR_DEVICE_ATTR(temp##offset##_input, S_IRUGO, show_temp,	\
  			NULL, offset - 1);				\
  static SENSOR_DEVICE_ATTR(temp##offset##_min, S_IRUGO | S_IWUSR,	\
  			show_temp_min, set_temp_min, offset - 1);	\
  static SENSOR_DEVICE_ATTR(temp##offset##_max, S_IRUGO | S_IWUSR,	\

  			show_temp_max, set_temp_max, offset - 1);	\
  static SENSOR_DEVICE_ATTR(temp##offset##_crit, S_IRUGO,			\
  			show_temp_critical, NULL, offset - 1);

  
  temp_reg(1);
  temp_reg(2);
  temp_reg(3);

  static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 0);
  static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL, 5);
  static SENSOR_DEVICE_ATTR(temp3_alarm, S_IRUGO, show_alarm, NULL, 1);
  static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 7);
  static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 2);

  static SENSOR_DEVICE_ATTR(pwm1, S_IRUGO | S_IWUSR, show_analog_out,
  			  set_analog_out, 0);
  static SENSOR_DEVICE_ATTR(pwm1_mode, S_IRUGO, show_pwm_mode, NULL, 0);
  
  static struct attribute *thmc50_attributes[] = {
  	&sensor_dev_attr_temp1_max.dev_attr.attr,
  	&sensor_dev_attr_temp1_min.dev_attr.attr,
  	&sensor_dev_attr_temp1_input.dev_attr.attr,

  	&sensor_dev_attr_temp1_crit.dev_attr.attr,

  	&sensor_dev_attr_temp1_alarm.dev_attr.attr,

  	&sensor_dev_attr_temp2_max.dev_attr.attr,
  	&sensor_dev_attr_temp2_min.dev_attr.attr,
  	&sensor_dev_attr_temp2_input.dev_attr.attr,

  	&sensor_dev_attr_temp2_crit.dev_attr.attr,

  	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp2_fault.dev_attr.attr,

  	&sensor_dev_attr_pwm1.dev_attr.attr,
  	&sensor_dev_attr_pwm1_mode.dev_attr.attr,
  	NULL
  };
  
  static const struct attribute_group thmc50_group = {
  	.attrs = thmc50_attributes,
  };
  
  /* for ADM1022 3rd temperature mode */

  static struct attribute *temp3_attributes[] = {

  	&sensor_dev_attr_temp3_max.dev_attr.attr,
  	&sensor_dev_attr_temp3_min.dev_attr.attr,
  	&sensor_dev_attr_temp3_input.dev_attr.attr,

  	&sensor_dev_attr_temp3_crit.dev_attr.attr,

  	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
  	&sensor_dev_attr_temp3_fault.dev_attr.attr,

  	NULL
  };

  static const struct attribute_group temp3_group = {
  	.attrs = temp3_attributes,

  };

  /* Return 0 if detection is successful, -ENODEV otherwise */

  static int thmc50_detect(struct i2c_client *client,

  			 struct i2c_board_info *info)

  {
  	unsigned company;
  	unsigned revision;
  	unsigned config;

  	struct i2c_adapter *adapter = client->adapter;

  	const char *type_name;

  
  	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
  		pr_debug("thmc50: detect failed, "
  			 "smbus byte data not supported!
  ");

  		return -ENODEV;

  	}

  	pr_debug("thmc50: Probing for THMC50 at 0x%2X on bus %d
  ",
  		 client->addr, i2c_adapter_id(client->adapter));

  	company = i2c_smbus_read_byte_data(client, THMC50_REG_COMPANY_ID);
  	revision = i2c_smbus_read_byte_data(client, THMC50_REG_DIE_CODE);
  	config = i2c_smbus_read_byte_data(client, THMC50_REG_CONF);

  	if (revision < 0xc0 || (config & 0x10))
  		return -ENODEV;

  	if (company == 0x41) {

  		int id = i2c_adapter_id(client->adapter);
  		int i;
  
  		type_name = "adm1022";

  		for (i = 0; i + 1 < adm1022_temp3_num; i += 2)
  			if (adm1022_temp3[i] == id &&

  			    adm1022_temp3[i + 1] == client->addr) {

  				/* enable 2nd remote temp */

  				config |= (1 << 7);
  				i2c_smbus_write_byte_data(client,
  							  THMC50_REG_CONF,
  							  config);

  				break;
  			}

  	} else if (company == 0x49) {

  		type_name = "thmc50";

  	} else {
  		pr_debug("thmc50: Detection of THMC50/ADM1022 failed
  ");
  		return -ENODEV;

  	}

  	pr_debug("thmc50: Detected %s (version %x, revision %x)
  ",
  		 type_name, (revision >> 4) - 0xc, revision & 0xf);

  	strlcpy(info->type, type_name, I2C_NAME_SIZE);

  	return 0;
  }
  
  static int thmc50_probe(struct i2c_client *client,
  			const struct i2c_device_id *id)
  {
  	struct thmc50_data *data;
  	int err;
  
  	data = kzalloc(sizeof(struct thmc50_data), GFP_KERNEL);
  	if (!data) {
  		pr_debug("thmc50: detect failed, kzalloc failed!
  ");
  		err = -ENOMEM;
  		goto exit;
  	}
  
  	i2c_set_clientdata(client, data);
  	data->type = id->driver_data;
  	mutex_init(&data->update_lock);

  
  	thmc50_init_client(client);
  
  	/* Register sysfs hooks */
  	if ((err = sysfs_create_group(&client->dev.kobj, &thmc50_group)))

  		goto exit_free;

  
  	/* Register ADM1022 sysfs hooks */

  	if (data->has_temp3)

  		if ((err = sysfs_create_group(&client->dev.kobj,

  					      &temp3_group)))

  			goto exit_remove_sysfs_thmc50;
  
  	/* Register a new directory entry with module sensors */

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

  		goto exit_remove_sysfs;
  	}
  
  	return 0;
  
  exit_remove_sysfs:

  	if (data->has_temp3)
  		sysfs_remove_group(&client->dev.kobj, &temp3_group);

  exit_remove_sysfs_thmc50:
  	sysfs_remove_group(&client->dev.kobj, &thmc50_group);

  exit_free:
  	kfree(data);
  exit:
  	return err;
  }

  static int thmc50_remove(struct i2c_client *client)

  {
  	struct thmc50_data *data = i2c_get_clientdata(client);

  	hwmon_device_unregister(data->hwmon_dev);

  	sysfs_remove_group(&client->dev.kobj, &thmc50_group);

  	if (data->has_temp3)
  		sysfs_remove_group(&client->dev.kobj, &temp3_group);

  	kfree(data);
  
  	return 0;
  }
  
  static void thmc50_init_client(struct i2c_client *client)
  {
  	struct thmc50_data *data = i2c_get_clientdata(client);
  	int config;
  
  	data->analog_out = i2c_smbus_read_byte_data(client,
  						    THMC50_REG_ANALOG_OUT);
  	/* set up to at least 1 */
  	if (data->analog_out == 0) {
  		data->analog_out = 1;
  		i2c_smbus_write_byte_data(client, THMC50_REG_ANALOG_OUT,
  					  data->analog_out);
  	}
  	config = i2c_smbus_read_byte_data(client, THMC50_REG_CONF);
  	config |= 0x1;	/* start the chip if it is in standby mode */

  	if (data->type == adm1022 && (config & (1 << 7)))
  		data->has_temp3 = 1;

  	i2c_smbus_write_byte_data(client, THMC50_REG_CONF, config);
  }
  
  static struct thmc50_data *thmc50_update_device(struct device *dev)
  {
  	struct i2c_client *client = to_i2c_client(dev);
  	struct thmc50_data *data = i2c_get_clientdata(client);
  	int timeout = HZ / 5 + (data->type == thmc50 ? HZ : 0);
  
  	mutex_lock(&data->update_lock);
  
  	if (time_after(jiffies, data->last_updated + timeout)
  	    || !data->valid) {
  
  		int temps = data->has_temp3 ? 3 : 2;
  		int i;

  		int prog = i2c_smbus_read_byte_data(client, THMC50_REG_CONF);
  
  		prog &= THMC50_REG_CONF_PROGRAMMED;

  		for (i = 0; i < temps; i++) {
  			data->temp_input[i] = i2c_smbus_read_byte_data(client,
  						THMC50_REG_TEMP[i]);
  			data->temp_max[i] = i2c_smbus_read_byte_data(client,
  						THMC50_REG_TEMP_MAX[i]);
  			data->temp_min[i] = i2c_smbus_read_byte_data(client,
  						THMC50_REG_TEMP_MIN[i]);

  			data->temp_critical[i] =
  				i2c_smbus_read_byte_data(client,
  					prog ? THMC50_REG_TEMP_CRITICAL[i]
  					     : THMC50_REG_TEMP_DEFAULT[i]);

  		}
  		data->analog_out =
  		    i2c_smbus_read_byte_data(client, THMC50_REG_ANALOG_OUT);

  		data->alarms =

  		    i2c_smbus_read_byte_data(client, THMC50_REG_INTR);

  		data->last_updated = jiffies;
  		data->valid = 1;
  	}
  
  	mutex_unlock(&data->update_lock);
  
  	return data;
  }
  
  static int __init sm_thmc50_init(void)
  {
  	return i2c_add_driver(&thmc50_driver);
  }
  
  static void __exit sm_thmc50_exit(void)
  {
  	i2c_del_driver(&thmc50_driver);
  }
  
  MODULE_AUTHOR("Krzysztof Helt <krzysztof.h1@wp.pl>");
  MODULE_DESCRIPTION("THMC50 driver");
  
  module_init(sm_thmc50_init);
  module_exit(sm_thmc50_exit);