/*

   * BQ27xxx battery monitor I2C driver

   *
   * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com/
   *	Andrew F. Davis <afd@ti.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   *
   * 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/i2c.h>
  #include <linux/interrupt.h>
  #include <linux/module.h>
  #include <asm/unaligned.h>
  
  #include <linux/power/bq27xxx_battery.h>

  static DEFINE_IDR(battery_id);
  static DEFINE_MUTEX(battery_mutex);

  static irqreturn_t bq27xxx_battery_irq_handler_thread(int irq, void *data)
  {
  	struct bq27xxx_device_info *di = data;
  
  	bq27xxx_battery_update(di);
  
  	return IRQ_HANDLED;
  }
  
  static int bq27xxx_battery_i2c_read(struct bq27xxx_device_info *di, u8 reg,
  				    bool single)
  {
  	struct i2c_client *client = to_i2c_client(di->dev);
  	struct i2c_msg msg[2];

  	u8 data[2];

  	int ret;
  
  	if (!client->adapter)
  		return -ENODEV;
  
  	msg[0].addr = client->addr;
  	msg[0].flags = 0;
  	msg[0].buf = ®
  	msg[0].len = sizeof(reg);
  	msg[1].addr = client->addr;
  	msg[1].flags = I2C_M_RD;
  	msg[1].buf = data;
  	if (single)
  		msg[1].len = 1;
  	else
  		msg[1].len = 2;
  
  	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
  	if (ret < 0)
  		return ret;
  
  	if (!single)
  		ret = get_unaligned_le16(data);
  	else
  		ret = data[0];
  
  	return ret;
  }

  static int bq27xxx_battery_i2c_write(struct bq27xxx_device_info *di, u8 reg,
  				     int value, bool single)
  {
  	struct i2c_client *client = to_i2c_client(di->dev);
  	struct i2c_msg msg;
  	u8 data[4];
  	int ret;
  
  	if (!client->adapter)
  		return -ENODEV;
  
  	data[0] = reg;
  	if (single) {
  		data[1] = (u8) value;
  		msg.len = 2;
  	} else {
  		put_unaligned_le16(value, &data[1]);
  		msg.len = 3;
  	}
  
  	msg.buf = data;
  	msg.addr = client->addr;
  	msg.flags = 0;
  
  	ret = i2c_transfer(client->adapter, &msg, 1);
  	if (ret < 0)
  		return ret;
  	if (ret != 1)
  		return -EINVAL;
  	return 0;
  }
  
  static int bq27xxx_battery_i2c_bulk_read(struct bq27xxx_device_info *di, u8 reg,
  					 u8 *data, int len)
  {
  	struct i2c_client *client = to_i2c_client(di->dev);
  	int ret;
  
  	if (!client->adapter)
  		return -ENODEV;
  
  	ret = i2c_smbus_read_i2c_block_data(client, reg, len, data);
  	if (ret < 0)
  		return ret;
  	if (ret != len)
  		return -EINVAL;
  	return 0;
  }
  
  static int bq27xxx_battery_i2c_bulk_write(struct bq27xxx_device_info *di,
  					  u8 reg, u8 *data, int len)
  {
  	struct i2c_client *client = to_i2c_client(di->dev);
  	struct i2c_msg msg;
  	u8 buf[33];
  	int ret;
  
  	if (!client->adapter)
  		return -ENODEV;
  
  	buf[0] = reg;
  	memcpy(&buf[1], data, len);
  
  	msg.buf = buf;
  	msg.addr = client->addr;
  	msg.flags = 0;
  	msg.len = len + 1;
  
  	ret = i2c_transfer(client->adapter, &msg, 1);
  	if (ret < 0)
  		return ret;
  	if (ret != 1)
  		return -EINVAL;
  	return 0;
  }

  static int bq27xxx_battery_i2c_probe(struct i2c_client *client,
  				     const struct i2c_device_id *id)
  {
  	struct bq27xxx_device_info *di;
  	int ret;

  	char *name;
  	int num;
  
  	/* Get new ID for the new battery device */
  	mutex_lock(&battery_mutex);
  	num = idr_alloc(&battery_id, client, 0, 0, GFP_KERNEL);
  	mutex_unlock(&battery_mutex);
  	if (num < 0)
  		return num;
  
  	name = devm_kasprintf(&client->dev, GFP_KERNEL, "%s-%d", id->name, num);
  	if (!name)
  		goto err_mem;

  
  	di = devm_kzalloc(&client->dev, sizeof(*di), GFP_KERNEL);
  	if (!di)

  		goto err_mem;

  	di->id = num;

  	di->dev = &client->dev;
  	di->chip = id->driver_data;

  	di->name = name;

  	di->bus.read = bq27xxx_battery_i2c_read;

  	di->bus.write = bq27xxx_battery_i2c_write;
  	di->bus.read_bulk = bq27xxx_battery_i2c_bulk_read;
  	di->bus.write_bulk = bq27xxx_battery_i2c_bulk_write;

  
  	ret = bq27xxx_battery_setup(di);
  	if (ret)

  		goto err_failed;

  
  	/* Schedule a polling after about 1 min */
  	schedule_delayed_work(&di->work, 60 * HZ);
  
  	i2c_set_clientdata(client, di);
  
  	if (client->irq) {
  		ret = devm_request_threaded_irq(&client->dev, client->irq,
  				NULL, bq27xxx_battery_irq_handler_thread,
  				IRQF_ONESHOT,
  				di->name, di);
  		if (ret) {
  			dev_err(&client->dev,
  				"Unable to register IRQ %d error %d
  ",
  				client->irq, ret);
  			return ret;
  		}
  	}
  
  	return 0;

  
  err_mem:
  	ret = -ENOMEM;
  
  err_failed:
  	mutex_lock(&battery_mutex);
  	idr_remove(&battery_id, num);
  	mutex_unlock(&battery_mutex);
  
  	return ret;

  }
  
  static int bq27xxx_battery_i2c_remove(struct i2c_client *client)
  {
  	struct bq27xxx_device_info *di = i2c_get_clientdata(client);
  
  	bq27xxx_battery_teardown(di);

  	mutex_lock(&battery_mutex);
  	idr_remove(&battery_id, di->id);
  	mutex_unlock(&battery_mutex);

  	return 0;
  }
  
  static const struct i2c_device_id bq27xxx_i2c_id_table[] = {
  	{ "bq27200", BQ27000 },
  	{ "bq27210", BQ27010 },

  	{ "bq27500", BQ2750X },

  	{ "bq27510", BQ2751X },

  	{ "bq27520", BQ2752X },

  	{ "bq27500-1", BQ27500 },

  	{ "bq27510g1", BQ27510G1 },

  	{ "bq27510g2", BQ27510G2 },

  	{ "bq27510g3", BQ27510G3 },

  	{ "bq27520g1", BQ27520G1 },

  	{ "bq27520g2", BQ27520G2 },

  	{ "bq27520g3", BQ27520G3 },

  	{ "bq27520g4", BQ27520G4 },

  	{ "bq27530", BQ27530 },

  	{ "bq27531", BQ27531 },

  	{ "bq27541", BQ27541 },

  	{ "bq27542", BQ27542 },
  	{ "bq27546", BQ27546 },
  	{ "bq27742", BQ27742 },

  	{ "bq27545", BQ27545 },
  	{ "bq27421", BQ27421 },

  	{ "bq27425", BQ27425 },
  	{ "bq27441", BQ27441 },
  	{ "bq27621", BQ27621 },

  	{},
  };
  MODULE_DEVICE_TABLE(i2c, bq27xxx_i2c_id_table);

  #ifdef CONFIG_OF
  static const struct of_device_id bq27xxx_battery_i2c_of_match_table[] = {
  	{ .compatible = "ti,bq27200" },
  	{ .compatible = "ti,bq27210" },
  	{ .compatible = "ti,bq27500" },
  	{ .compatible = "ti,bq27510" },
  	{ .compatible = "ti,bq27520" },

  	{ .compatible = "ti,bq27500-1" },

  	{ .compatible = "ti,bq27510g1" },

  	{ .compatible = "ti,bq27510g2" },

  	{ .compatible = "ti,bq27510g3" },

  	{ .compatible = "ti,bq27520g1" },

  	{ .compatible = "ti,bq27520g2" },

  	{ .compatible = "ti,bq27520g3" },

  	{ .compatible = "ti,bq27520g4" },

  	{ .compatible = "ti,bq27530" },
  	{ .compatible = "ti,bq27531" },
  	{ .compatible = "ti,bq27541" },
  	{ .compatible = "ti,bq27542" },
  	{ .compatible = "ti,bq27546" },
  	{ .compatible = "ti,bq27742" },
  	{ .compatible = "ti,bq27545" },
  	{ .compatible = "ti,bq27421" },
  	{ .compatible = "ti,bq27425" },
  	{ .compatible = "ti,bq27441" },
  	{ .compatible = "ti,bq27621" },
  	{},
  };
  MODULE_DEVICE_TABLE(of, bq27xxx_battery_i2c_of_match_table);
  #endif

  static struct i2c_driver bq27xxx_battery_i2c_driver = {
  	.driver = {
  		.name = "bq27xxx-battery",

  		.of_match_table = of_match_ptr(bq27xxx_battery_i2c_of_match_table),

  	},
  	.probe = bq27xxx_battery_i2c_probe,
  	.remove = bq27xxx_battery_i2c_remove,
  	.id_table = bq27xxx_i2c_id_table,
  };
  module_i2c_driver(bq27xxx_battery_i2c_driver);
  
  MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
  MODULE_DESCRIPTION("BQ27xxx battery monitor i2c driver");
  MODULE_LICENSE("GPL");