text: /*
   * tps65217.c
   *
   * TPS65217 chip family multi-function driver
   *
   * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.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/device.h>
  #include <linux/module.h>
  #include <linux/platform_device.h>
  #include <linux/init.h>
  #include <linux/i2c.h>
  #include <linux/slab.h>
  #include <linux/regmap.h>
  #include <linux/err.h>
  #include <linux/of.h>
  #include <linux/of_device.h>
  
  #include <linux/mfd/core.h>
  #include <linux/mfd/tps65217.h>
  
  static struct mfd_cell tps65217s[] = {
  	{
  		.name = "tps65217-pmic",
  	},
  	{
  		.name = "tps65217-bl",
  	},
  };
  
  /**
   * tps65217_reg_read: Read a single tps65217 register.
   *
   * @tps: Device to read from.
   * @reg: Register to read.
   * @val: Contians the value
   */
  int tps65217_reg_read(struct tps65217 *tps, unsigned int reg,
  			unsigned int *val)
  {
  	return regmap_read(tps->regmap, reg, val);
  }
  EXPORT_SYMBOL_GPL(tps65217_reg_read);
  
  /**
   * tps65217_reg_write: Write a single tps65217 register.
   *
   * @tps65217: Device to write to.
   * @reg: Register to write to.
   * @val: Value to write.
   * @level: Password protected level
   */
  int tps65217_reg_write(struct tps65217 *tps, unsigned int reg,
  			unsigned int val, unsigned int level)
  {
  	int ret;
  	unsigned int xor_reg_val;
  
  	switch (level) {
  	case TPS65217_PROTECT_NONE:
  		return regmap_write(tps->regmap, reg, val);
  	case TPS65217_PROTECT_L1:
  		xor_reg_val = reg ^ TPS65217_PASSWORD_REGS_UNLOCK;
  		ret = regmap_write(tps->regmap, TPS65217_REG_PASSWORD,
  							xor_reg_val);
  		if (ret < 0)
  			return ret;
  
  		return regmap_write(tps->regmap, reg, val);
  	case TPS65217_PROTECT_L2:
  		xor_reg_val = reg ^ TPS65217_PASSWORD_REGS_UNLOCK;
  		ret = regmap_write(tps->regmap, TPS65217_REG_PASSWORD,
  							xor_reg_val);
  		if (ret < 0)
  			return ret;
  		ret = regmap_write(tps->regmap, reg, val);
  		if (ret < 0)
  			return ret;
  		ret = regmap_write(tps->regmap, TPS65217_REG_PASSWORD,
  							xor_reg_val);
  		if (ret < 0)
  			return ret;
  		return regmap_write(tps->regmap, reg, val);
  	default:
  		return -EINVAL;
  	}
  }
  EXPORT_SYMBOL_GPL(tps65217_reg_write);
  
  /**
   * tps65217_update_bits: Modify bits w.r.t mask, val and level.
   *
   * @tps65217: Device to write to.
   * @reg: Register to read-write to.
   * @mask: Mask.
   * @val: Value to write.
   * @level: Password protected level
   */
  static int tps65217_update_bits(struct tps65217 *tps, unsigned int reg,
  		unsigned int mask, unsigned int val, unsigned int level)
  {
  	int ret;
  	unsigned int data;
  
  	ret = tps65217_reg_read(tps, reg, &data);
  	if (ret) {
  		dev_err(tps->dev, "Read from reg 0x%x failed\n", reg);
  		return ret;
  	}
  
  	data &= ~mask;
  	data |= val & mask;
  
  	ret = tps65217_reg_write(tps, reg, data, level);
  	if (ret)
  		dev_err(tps->dev, "Write for reg 0x%x failed\n", reg);
  
  	return ret;
  }
  
  int tps65217_set_bits(struct tps65217 *tps, unsigned int reg,
  		unsigned int mask, unsigned int val, unsigned int level)
  {
  	return tps65217_update_bits(tps, reg, mask, val, level);
  }
  EXPORT_SYMBOL_GPL(tps65217_set_bits);
  
  int tps65217_clear_bits(struct tps65217 *tps, unsigned int reg,
  		unsigned int mask, unsigned int level)
  {
  	return tps65217_update_bits(tps, reg, mask, 0, level);
  }
  EXPORT_SYMBOL_GPL(tps65217_clear_bits);
  
  static struct regmap_config tps65217_regmap_config = {
  	.reg_bits = 8,
  	.val_bits = 8,
  };
  
  static const struct of_device_id tps65217_of_match[] = {
  	{ .compatible = "ti,tps65217", .data = (void *)TPS65217 },
  	{ /* sentinel */ },
  };
  
  static int tps65217_probe(struct i2c_client *client,
  				const struct i2c_device_id *ids)
  {
  	struct tps65217 *tps;
  	unsigned int version;
  	unsigned int chip_id = ids->driver_data;
  	const struct of_device_id *match;
  	bool status_off = false;
  	int ret;
  
  	if (client->dev.of_node) {
  		match = of_match_device(tps65217_of_match, &client->dev);
  		if (!match) {
  			dev_err(&client->dev,
  				"Failed to find matching dt id\n");
  			return -EINVAL;
  		}
  		chip_id = (unsigned int)match->data;
  		status_off = of_property_read_bool(client->dev.of_node,
  					"ti,pmic-shutdown-controller");
  	}
  
  	if (!chip_id) {
  		dev_err(&client->dev, "id is null.\n");
  		return -ENODEV;
  	}
  
  	tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL);
  	if (!tps)
  		return -ENOMEM;
  
  	i2c_set_clientdata(client, tps);
  	tps->dev = &client->dev;
  	tps->id = chip_id;
  
  	tps->regmap = devm_regmap_init_i2c(client, &tps65217_regmap_config);
  	if (IS_ERR(tps->regmap)) {
  		ret = PTR_ERR(tps->regmap);
  		dev_err(tps->dev, "Failed to allocate register map: %d\n",
  			ret);
  		return ret;
  	}
  
  	ret = mfd_add_devices(tps->dev, -1, tps65217s,
  			      ARRAY_SIZE(tps65217s), NULL, 0, NULL);
  	if (ret < 0) {
  		dev_err(tps->dev, "mfd_add_devices failed: %d\n", ret);
  		return ret;
  	}
  
  	ret = tps65217_reg_read(tps, TPS65217_REG_CHIPID, &version);
  	if (ret < 0) {
  		dev_err(tps->dev, "Failed to read revision register: %d\n",
  			ret);
  		return ret;
  	}
  
  	/* Set the PMIC to shutdown on PWR_EN toggle */
  	if (status_off) {
  		ret = tps65217_set_bits(tps, TPS65217_REG_STATUS,
  				TPS65217_STATUS_OFF, TPS65217_STATUS_OFF,
  				TPS65217_PROTECT_NONE);
  		if (ret)
  			dev_warn(tps->dev, "unable to set the status OFF\n");
  	}
  
  	dev_info(tps->dev, "TPS65217 ID %#x version 1.%d\n",
  			(version & TPS65217_CHIPID_CHIP_MASK) >> 4,
  			version & TPS65217_CHIPID_REV_MASK);
  
  	return 0;
  }
  
  static int tps65217_remove(struct i2c_client *client)
  {
  	struct tps65217 *tps = i2c_get_clientdata(client);
  
  	mfd_remove_devices(tps->dev);
  
  	return 0;
  }
  
  static const struct i2c_device_id tps65217_id_table[] = {
  	{"tps65217", TPS65217},
  	{ /* sentinel */ }
  };
  MODULE_DEVICE_TABLE(i2c, tps65217_id_table);
  
  static struct i2c_driver tps65217_driver = {
  	.driver		= {
  		.name	= "tps65217",
  		.owner	= THIS_MODULE,
  		.of_match_table = tps65217_of_match,
  	},
  	.id_table	= tps65217_id_table,
  	.probe		= tps65217_probe,
  	.remove		= tps65217_remove,
  };
  
  static int __init tps65217_init(void)
  {
  	return i2c_add_driver(&tps65217_driver);
  }
  subsys_initcall(tps65217_init);
  
  static void __exit tps65217_exit(void)
  {
  	i2c_del_driver(&tps65217_driver);
  }
  module_exit(tps65217_exit);
  
  MODULE_AUTHOR("AnilKumar Ch <anilkumar@ti.com>");
  MODULE_DESCRIPTION("TPS65217 chip family multi-function driver");
  MODULE_LICENSE("GPL v2");
  