/*

   * I2C driver for Marvell 88PM860x

   *
   * Copyright (C) 2009 Marvell International Ltd.

   *
   * Author: Haojian Zhuang <haojian.zhuang@marvell.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.
   */
  #include <linux/kernel.h>
  #include <linux/module.h>

  #include <linux/i2c.h>

  #include <linux/regmap.h>

  #include <linux/mfd/88pm860x.h>

  int pm860x_reg_read(struct i2c_client *i2c, int reg)

  {

  	struct pm860x_chip *chip = i2c_get_clientdata(i2c);

  	struct regmap *map = (i2c == chip->client) ? chip->regmap
  				: chip->regmap_companion;
  	unsigned int data;

  	int ret;

  	ret = regmap_read(map, reg, &data);

  	if (ret < 0)
  		return ret;
  	else
  		return (int)data;
  }

  EXPORT_SYMBOL(pm860x_reg_read);

  int pm860x_reg_write(struct i2c_client *i2c, int reg,

  		     unsigned char data)
  {

  	struct pm860x_chip *chip = i2c_get_clientdata(i2c);

  	struct regmap *map = (i2c == chip->client) ? chip->regmap
  				: chip->regmap_companion;

  	int ret;

  	ret = regmap_write(map, reg, data);

  	return ret;
  }

  EXPORT_SYMBOL(pm860x_reg_write);

  int pm860x_bulk_read(struct i2c_client *i2c, int reg,

  		     int count, unsigned char *buf)
  {

  	struct pm860x_chip *chip = i2c_get_clientdata(i2c);

  	struct regmap *map = (i2c == chip->client) ? chip->regmap
  				: chip->regmap_companion;

  	int ret;

  	ret = regmap_raw_read(map, reg, buf, count);

  	return ret;
  }

  EXPORT_SYMBOL(pm860x_bulk_read);

  int pm860x_bulk_write(struct i2c_client *i2c, int reg,

  		      int count, unsigned char *buf)
  {

  	struct pm860x_chip *chip = i2c_get_clientdata(i2c);

  	struct regmap *map = (i2c == chip->client) ? chip->regmap
  				: chip->regmap_companion;

  	int ret;

  	ret = regmap_raw_write(map, reg, buf, count);

  	return ret;
  }

  EXPORT_SYMBOL(pm860x_bulk_write);

  int pm860x_set_bits(struct i2c_client *i2c, int reg,

  		    unsigned char mask, unsigned char data)
  {

  	struct pm860x_chip *chip = i2c_get_clientdata(i2c);

  	struct regmap *map = (i2c == chip->client) ? chip->regmap
  				: chip->regmap_companion;

  	int ret;

  	ret = regmap_update_bits(map, reg, mask, data);

  	return ret;
  }

  EXPORT_SYMBOL(pm860x_set_bits);

  static int read_device(struct i2c_client *i2c, int reg,
  		       int bytes, void *dest)
  {
  	unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX + 3];
  	unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX + 2];
  	struct i2c_adapter *adap = i2c->adapter;

  	struct i2c_msg msg[2] = {
  					{
  						.addr = i2c->addr,
  						.flags = 0,
  						.len = 1,
  						.buf = msgbuf0
  					},
  					{	.addr = i2c->addr,
  						.flags = I2C_M_RD,
  						.len = 0,
  						.buf = msgbuf1
  					},

  				};
  	int num = 1, ret = 0;
  
  	if (dest == NULL)
  		return -EINVAL;
  	msgbuf0[0] = (unsigned char)reg;	/* command */
  	msg[1].len = bytes;
  
  	/* if data needs to read back, num should be 2 */
  	if (bytes > 0)
  		num = 2;
  	ret = adap->algo->master_xfer(adap, msg, num);
  	memcpy(dest, msgbuf1, bytes);
  	if (ret < 0)
  		return ret;
  	return 0;
  }
  
  static int write_device(struct i2c_client *i2c, int reg,
  			int bytes, void *src)
  {

  	unsigned char buf[2];

  	struct i2c_adapter *adap = i2c->adapter;
  	struct i2c_msg msg;
  	int ret;
  
  	buf[0] = (unsigned char)reg;
  	memcpy(&buf[1], src, bytes);
  	msg.addr = i2c->addr;
  	msg.flags = 0;
  	msg.len = bytes + 1;
  	msg.buf = buf;
  
  	ret = adap->algo->master_xfer(adap, &msg, 1);
  	if (ret < 0)
  		return ret;
  	return 0;
  }

  int pm860x_page_reg_write(struct i2c_client *i2c, int reg,
  			  unsigned char data)
  {

  	unsigned char zero;
  	int ret;

  	i2c_lock_adapter(i2c->adapter);
  	read_device(i2c, 0xFA, 0, &zero);
  	read_device(i2c, 0xFB, 0, &zero);
  	read_device(i2c, 0xFF, 0, &zero);
  	ret = write_device(i2c, reg, 1, &data);
  	read_device(i2c, 0xFE, 0, &zero);
  	read_device(i2c, 0xFC, 0, &zero);
  	i2c_unlock_adapter(i2c->adapter);

  	return ret;
  }
  EXPORT_SYMBOL(pm860x_page_reg_write);
  
  int pm860x_page_bulk_read(struct i2c_client *i2c, int reg,
  			  int count, unsigned char *buf)
  {

  	unsigned char zero = 0;
  	int ret;

  	i2c_lock_adapter(i2c->adapter);
  	read_device(i2c, 0xfa, 0, &zero);
  	read_device(i2c, 0xfb, 0, &zero);
  	read_device(i2c, 0xff, 0, &zero);
  	ret = read_device(i2c, reg, count, buf);
  	read_device(i2c, 0xFE, 0, &zero);
  	read_device(i2c, 0xFC, 0, &zero);
  	i2c_unlock_adapter(i2c->adapter);

  	return ret;
  }
  EXPORT_SYMBOL(pm860x_page_bulk_read);