text: /*
   * isl6271a-regulator.c
   *
   * Support for Intersil ISL6271A voltage regulator
   *
   * Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.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 version 2.
   *
   * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
   * whether express or implied; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * General Public License for more details.
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/err.h>
  #include <linux/platform_device.h>
  #include <linux/regulator/driver.h>
  #include <linux/i2c.h>
  #include <linux/slab.h>
  
  #define	ISL6271A_VOLTAGE_MIN	850000
  #define	ISL6271A_VOLTAGE_MAX	1600000
  #define	ISL6271A_VOLTAGE_STEP	50000
  
  /* PMIC details */
  struct isl_pmic {
  	struct i2c_client	*client;
  	struct regulator_dev	*rdev[3];
  	struct mutex		mtx;
  };
  
  static int isl6271a_get_voltage_sel(struct regulator_dev *dev)
  {
  	struct isl_pmic *pmic = rdev_get_drvdata(dev);
  	int idx;
  
  	mutex_lock(&pmic->mtx);
  
  	idx = i2c_smbus_read_byte(pmic->client);
  	if (idx < 0)
  		dev_err(&pmic->client->dev, "Error getting voltage\n");
  
  	mutex_unlock(&pmic->mtx);
  	return idx;
  }
  
  static int isl6271a_set_voltage_sel(struct regulator_dev *dev,
  				    unsigned selector)
  {
  	struct isl_pmic *pmic = rdev_get_drvdata(dev);
  	int err;
  
  	mutex_lock(&pmic->mtx);
  
  	err = i2c_smbus_write_byte(pmic->client, selector);
  	if (err < 0)
  		dev_err(&pmic->client->dev, "Error setting voltage\n");
  
  	mutex_unlock(&pmic->mtx);
  	return err;
  }
  
  static struct regulator_ops isl_core_ops = {
  	.get_voltage_sel = isl6271a_get_voltage_sel,
  	.set_voltage_sel = isl6271a_set_voltage_sel,
  	.list_voltage	= regulator_list_voltage_linear,
  	.map_voltage	= regulator_map_voltage_linear,
  };
  
  static struct regulator_ops isl_fixed_ops = {
  	.list_voltage	= regulator_list_voltage_linear,
  };
  
  static const struct regulator_desc isl_rd[] = {
  	{
  		.name		= "Core Buck",
  		.id		= 0,
  		.n_voltages	= 16,
  		.ops		= &isl_core_ops,
  		.type		= REGULATOR_VOLTAGE,
  		.owner		= THIS_MODULE,
  		.min_uV		= ISL6271A_VOLTAGE_MIN,
  		.uV_step	= ISL6271A_VOLTAGE_STEP,
  	}, {
  		.name		= "LDO1",
  		.id		= 1,
  		.n_voltages	= 1,
  		.ops		= &isl_fixed_ops,
  		.type		= REGULATOR_VOLTAGE,
  		.owner		= THIS_MODULE,
  		.min_uV		= 1100000,
  	}, {
  		.name		= "LDO2",
  		.id		= 2,
  		.n_voltages	= 1,
  		.ops		= &isl_fixed_ops,
  		.type		= REGULATOR_VOLTAGE,
  		.owner		= THIS_MODULE,
  		.min_uV		= 1300000,
  	},
  };
  
  static int isl6271a_probe(struct i2c_client *i2c,
  				     const struct i2c_device_id *id)
  {
  	struct regulator_config config = { };
  	struct regulator_init_data *init_data	= i2c->dev.platform_data;
  	struct isl_pmic *pmic;
  	int err, i;
  
  	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
  		return -EIO;
  
  	pmic = devm_kzalloc(&i2c->dev, sizeof(struct isl_pmic), GFP_KERNEL);
  	if (!pmic)
  		return -ENOMEM;
  
  	pmic->client = i2c;
  
  	mutex_init(&pmic->mtx);
  
  	for (i = 0; i < 3; i++) {
  		config.dev = &i2c->dev;
  		if (i == 0)
  			config.init_data = init_data;
  		else
  			config.init_data = 0;
  		config.driver_data = pmic;
  
  		pmic->rdev[i] = regulator_register(&isl_rd[i], &config);
  		if (IS_ERR(pmic->rdev[i])) {
  			dev_err(&i2c->dev, "failed to register %s\n", id->name);
  			err = PTR_ERR(pmic->rdev[i]);
  			goto error;
  		}
  	}
  
  	i2c_set_clientdata(i2c, pmic);
  
  	return 0;
  
  error:
  	while (--i >= 0)
  		regulator_unregister(pmic->rdev[i]);
  	return err;
  }
  
  static int isl6271a_remove(struct i2c_client *i2c)
  {
  	struct isl_pmic *pmic = i2c_get_clientdata(i2c);
  	int i;
  
  	for (i = 0; i < 3; i++)
  		regulator_unregister(pmic->rdev[i]);
  	return 0;
  }
  
  static const struct i2c_device_id isl6271a_id[] = {
  	{.name = "isl6271a", 0 },
  	{ },
  };
  
  MODULE_DEVICE_TABLE(i2c, isl6271a_id);
  
  static struct i2c_driver isl6271a_i2c_driver = {
  	.driver = {
  		.name = "isl6271a",
  		.owner = THIS_MODULE,
  	},
  	.probe = isl6271a_probe,
  	.remove = isl6271a_remove,
  	.id_table = isl6271a_id,
  };
  
  static int __init isl6271a_init(void)
  {
  	return i2c_add_driver(&isl6271a_i2c_driver);
  }
  
  static void __exit isl6271a_cleanup(void)
  {
  	i2c_del_driver(&isl6271a_i2c_driver);
  }
  
  subsys_initcall(isl6271a_init);
  module_exit(isl6271a_cleanup);
  
  MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
  MODULE_DESCRIPTION("Intersil ISL6271A voltage regulator driver");
  MODULE_LICENSE("GPL v2");
  