/* NXP PCF50633 Main Battery Charger Driver
   *
   * (C) 2006-2008 by Openmoko, Inc.
   * Author: Balaji Rao <balajirrao@openmoko.org>
   * All rights reserved.
   *
   * Broken down from monstrous PCF50633 driver mainly by
   * Harald Welte, Andy Green and Werner Almesberger
   *
   *  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.
   *
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>

  #include <linux/slab.h>

  #include <linux/init.h>
  #include <linux/types.h>
  #include <linux/device.h>
  #include <linux/sysfs.h>
  #include <linux/platform_device.h>
  #include <linux/power_supply.h>
  
  #include <linux/mfd/pcf50633/core.h>
  #include <linux/mfd/pcf50633/mbc.h>
  
  struct pcf50633_mbc {
  	struct pcf50633 *pcf;

  	int adapter_online;

  	int usb_online;

  	struct power_supply *usb;
  	struct power_supply *adapter;
  	struct power_supply *ac;

  };
  
  int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma)
  {
  	struct pcf50633_mbc *mbc = platform_get_drvdata(pcf->mbc_pdev);
  	int ret = 0;
  	u8 bits;

  	int charging_start = 1;
  	u8 mbcs2, chgmod;

  	unsigned int mbcc5;

  	if (ma >= 1000) {

  		bits = PCF50633_MBCC7_USB_1000mA;

  		ma = 1000;
  	} else if (ma >= 500) {

  		bits = PCF50633_MBCC7_USB_500mA;

  		ma = 500;
  	} else if (ma >= 100) {

  		bits = PCF50633_MBCC7_USB_100mA;

  		ma = 100;
  	} else {

  		bits = PCF50633_MBCC7_USB_SUSPEND;

  		charging_start = 0;

  		ma = 0;

  	}

  
  	ret = pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC7,
  					PCF50633_MBCC7_USB_MASK, bits);
  	if (ret)
  		dev_err(pcf->dev, "error setting usb curlim to %d mA
  ", ma);
  	else
  		dev_info(pcf->dev, "usb curlim to %d mA
  ", ma);

  	/*
  	 * We limit the charging current to be the USB current limit.
  	 * The reason is that on pcf50633, when it enters PMU Standby mode,
  	 * which it does when the device goes "off", the USB current limit
  	 * reverts to the variant default.  In at least one common case, that
  	 * default is 500mA.  By setting the charging current to be the same
  	 * as the USB limit we set here before PMU standby, we enforce it only
  	 * using the correct amount of current even when the USB current limit
  	 * gets reset to the wrong thing
  	 */
  
  	if (mbc->pcf->pdata->charger_reference_current_ma) {
  		mbcc5 = (ma << 8) / mbc->pcf->pdata->charger_reference_current_ma;
  		if (mbcc5 > 255)
  			mbcc5 = 255;
  		pcf50633_reg_write(mbc->pcf, PCF50633_REG_MBCC5, mbcc5);
  	}

  	mbcs2 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS2);

  	chgmod = (mbcs2 & PCF50633_MBCS2_MBC_MASK);
  
  	/* If chgmod == BATFULL, setting chgena has no effect.

  	 * Datasheet says we need to set resume instead but when autoresume is
  	 * used resume doesn't work. Clear and set chgena instead.

  	 */
  	if (chgmod != PCF50633_MBCS2_MBC_BAT_FULL)
  		pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC1,
  				PCF50633_MBCC1_CHGENA, PCF50633_MBCC1_CHGENA);

  	else {
  		pcf50633_reg_clear_bits(pcf, PCF50633_REG_MBCC1,
  				PCF50633_MBCC1_CHGENA);

  		pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC1,

  				PCF50633_MBCC1_CHGENA, PCF50633_MBCC1_CHGENA);
  	}

  	power_supply_changed(mbc->usb);

  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(pcf50633_mbc_usb_curlim_set);
  
  int pcf50633_mbc_get_status(struct pcf50633 *pcf)
  {
  	struct pcf50633_mbc *mbc  = platform_get_drvdata(pcf->mbc_pdev);
  	int status = 0;

  	u8 chgmod;
  
  	if (!mbc)
  		return 0;
  
  	chgmod = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS2)
  		& PCF50633_MBCS2_MBC_MASK;

  
  	if (mbc->usb_online)
  		status |= PCF50633_MBC_USB_ONLINE;

  	if (chgmod == PCF50633_MBCS2_MBC_USB_PRE ||
  	    chgmod == PCF50633_MBCS2_MBC_USB_PRE_WAIT ||
  	    chgmod == PCF50633_MBCS2_MBC_USB_FAST ||
  	    chgmod == PCF50633_MBCS2_MBC_USB_FAST_WAIT)

  		status |= PCF50633_MBC_USB_ACTIVE;
  	if (mbc->adapter_online)
  		status |= PCF50633_MBC_ADAPTER_ONLINE;

  	if (chgmod == PCF50633_MBCS2_MBC_ADP_PRE ||
  	    chgmod == PCF50633_MBCS2_MBC_ADP_PRE_WAIT ||
  	    chgmod == PCF50633_MBCS2_MBC_ADP_FAST ||
  	    chgmod == PCF50633_MBCS2_MBC_ADP_FAST_WAIT)

  		status |= PCF50633_MBC_ADAPTER_ACTIVE;
  
  	return status;
  }
  EXPORT_SYMBOL_GPL(pcf50633_mbc_get_status);

  int pcf50633_mbc_get_usb_online_status(struct pcf50633 *pcf)
  {
  	struct pcf50633_mbc *mbc  = platform_get_drvdata(pcf->mbc_pdev);
  
  	if (!mbc)
  		return 0;
  
  	return mbc->usb_online;
  }
  EXPORT_SYMBOL_GPL(pcf50633_mbc_get_usb_online_status);

  static ssize_t
  show_chgmode(struct device *dev, struct device_attribute *attr, char *buf)
  {
  	struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
  
  	u8 mbcs2 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS2);
  	u8 chgmod = (mbcs2 & PCF50633_MBCS2_MBC_MASK);
  
  	return sprintf(buf, "%d
  ", chgmod);
  }
  static DEVICE_ATTR(chgmode, S_IRUGO, show_chgmode, NULL);
  
  static ssize_t
  show_usblim(struct device *dev, struct device_attribute *attr, char *buf)
  {
  	struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
  	u8 usblim = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC7) &
  						PCF50633_MBCC7_USB_MASK;
  	unsigned int ma;
  
  	if (usblim == PCF50633_MBCC7_USB_1000mA)
  		ma = 1000;
  	else if (usblim == PCF50633_MBCC7_USB_500mA)
  		ma = 500;
  	else if (usblim == PCF50633_MBCC7_USB_100mA)
  		ma = 100;
  	else
  		ma = 0;
  
  	return sprintf(buf, "%u
  ", ma);
  }
  
  static ssize_t set_usblim(struct device *dev,
  		struct device_attribute *attr, const char *buf, size_t count)
  {
  	struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
  	unsigned long ma;
  	int ret;

  	ret = kstrtoul(buf, 10, &ma);

  	if (ret)

  		return ret;

  
  	pcf50633_mbc_usb_curlim_set(mbc->pcf, ma);
  
  	return count;
  }
  
  static DEVICE_ATTR(usb_curlim, S_IRUGO | S_IWUSR, show_usblim, set_usblim);

  static ssize_t
  show_chglim(struct device *dev, struct device_attribute *attr, char *buf)
  {
  	struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
  	u8 mbcc5 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC5);
  	unsigned int ma;
  
  	if (!mbc->pcf->pdata->charger_reference_current_ma)
  		return -ENODEV;
  
  	ma = (mbc->pcf->pdata->charger_reference_current_ma *  mbcc5) >> 8;
  
  	return sprintf(buf, "%u
  ", ma);
  }
  
  static ssize_t set_chglim(struct device *dev,
  		struct device_attribute *attr, const char *buf, size_t count)
  {
  	struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
  	unsigned long ma;
  	unsigned int mbcc5;
  	int ret;
  
  	if (!mbc->pcf->pdata->charger_reference_current_ma)
  		return -ENODEV;

  	ret = kstrtoul(buf, 10, &ma);

  	if (ret)

  		return ret;

  
  	mbcc5 = (ma << 8) / mbc->pcf->pdata->charger_reference_current_ma;
  	if (mbcc5 > 255)
  		mbcc5 = 255;
  	pcf50633_reg_write(mbc->pcf, PCF50633_REG_MBCC5, mbcc5);
  
  	return count;
  }
  
  /*
   * This attribute allows to change MBC charging limit on the fly
   * independently of usb current limit. It also gets set automatically every
   * time usb current limit is changed.
   */
  static DEVICE_ATTR(chg_curlim, S_IRUGO | S_IWUSR, show_chglim, set_chglim);

  static struct attribute *pcf50633_mbc_sysfs_entries[] = {
  	&dev_attr_chgmode.attr,
  	&dev_attr_usb_curlim.attr,

  	&dev_attr_chg_curlim.attr,

  	NULL,
  };
  
  static struct attribute_group mbc_attr_group = {
  	.name	= NULL,			/* put in device directory */
  	.attrs	= pcf50633_mbc_sysfs_entries,
  };
  
  static void
  pcf50633_mbc_irq_handler(int irq, void *data)
  {
  	struct pcf50633_mbc *mbc = data;
  
  	/* USB */
  	if (irq == PCF50633_IRQ_USBINS) {
  		mbc->usb_online = 1;
  	} else if (irq == PCF50633_IRQ_USBREM) {
  		mbc->usb_online = 0;

  		pcf50633_mbc_usb_curlim_set(mbc->pcf, 0);
  	}
  
  	/* Adapter */

  	if (irq == PCF50633_IRQ_ADPINS)

  		mbc->adapter_online = 1;

  	else if (irq == PCF50633_IRQ_ADPREM)

  		mbc->adapter_online = 0;

  	power_supply_changed(mbc->ac);
  	power_supply_changed(mbc->usb);
  	power_supply_changed(mbc->adapter);

  
  	if (mbc->pcf->pdata->mbc_event_callback)
  		mbc->pcf->pdata->mbc_event_callback(mbc->pcf, irq);
  }
  
  static int adapter_get_property(struct power_supply *psy,
  			enum power_supply_property psp,
  			union power_supply_propval *val)
  {

  	struct pcf50633_mbc *mbc = power_supply_get_drvdata(psy);

  	int ret = 0;
  
  	switch (psp) {
  	case POWER_SUPPLY_PROP_ONLINE:
  		val->intval =  mbc->adapter_online;
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  	return ret;
  }
  
  static int usb_get_property(struct power_supply *psy,
  			enum power_supply_property psp,
  			union power_supply_propval *val)
  {

  	struct pcf50633_mbc *mbc = power_supply_get_drvdata(psy);

  	int ret = 0;

  	u8 usblim = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC7) &
  						PCF50633_MBCC7_USB_MASK;

  
  	switch (psp) {
  	case POWER_SUPPLY_PROP_ONLINE:

  		val->intval = mbc->usb_online &&
  				(usblim <= PCF50633_MBCC7_USB_500mA);
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  	return ret;
  }
  
  static int ac_get_property(struct power_supply *psy,
  			enum power_supply_property psp,
  			union power_supply_propval *val)
  {

  	struct pcf50633_mbc *mbc = power_supply_get_drvdata(psy);

  	int ret = 0;
  	u8 usblim = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC7) &
  						PCF50633_MBCC7_USB_MASK;

  
  	switch (psp) {
  	case POWER_SUPPLY_PROP_ONLINE:

  		val->intval = mbc->usb_online &&
  				(usblim == PCF50633_MBCC7_USB_1000mA);

  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  	return ret;
  }
  
  static enum power_supply_property power_props[] = {
  	POWER_SUPPLY_PROP_ONLINE,
  };
  
  static const u8 mbc_irq_handlers[] = {
  	PCF50633_IRQ_ADPINS,
  	PCF50633_IRQ_ADPREM,
  	PCF50633_IRQ_USBINS,
  	PCF50633_IRQ_USBREM,
  	PCF50633_IRQ_BATFULL,
  	PCF50633_IRQ_CHGHALT,
  	PCF50633_IRQ_THLIMON,
  	PCF50633_IRQ_THLIMOFF,
  	PCF50633_IRQ_USBLIMON,
  	PCF50633_IRQ_USBLIMOFF,
  	PCF50633_IRQ_LOWSYS,
  	PCF50633_IRQ_LOWBAT,
  };

  static const struct power_supply_desc pcf50633_mbc_adapter_desc = {
  	.name		= "adapter",
  	.type		= POWER_SUPPLY_TYPE_MAINS,
  	.properties	= power_props,
  	.num_properties	= ARRAY_SIZE(power_props),
  	.get_property	= &adapter_get_property,
  };
  
  static const struct power_supply_desc pcf50633_mbc_usb_desc = {
  	.name		= "usb",
  	.type		= POWER_SUPPLY_TYPE_USB,
  	.properties	= power_props,
  	.num_properties	= ARRAY_SIZE(power_props),
  	.get_property	= usb_get_property,
  };
  
  static const struct power_supply_desc pcf50633_mbc_ac_desc = {
  	.name		= "ac",
  	.type		= POWER_SUPPLY_TYPE_MAINS,
  	.properties	= power_props,
  	.num_properties	= ARRAY_SIZE(power_props),
  	.get_property	= ac_get_property,
  };

  static int pcf50633_mbc_probe(struct platform_device *pdev)

  {

  	struct power_supply_config psy_cfg = {};

  	struct pcf50633_mbc *mbc;

  	int ret;
  	int i;
  	u8 mbcs1;

  	mbc = devm_kzalloc(&pdev->dev, sizeof(*mbc), GFP_KERNEL);

  	if (!mbc)
  		return -ENOMEM;
  
  	platform_set_drvdata(pdev, mbc);

  	mbc->pcf = dev_to_pcf50633(pdev->dev.parent);

  
  	/* Set up IRQ handlers */
  	for (i = 0; i < ARRAY_SIZE(mbc_irq_handlers); i++)
  		pcf50633_register_irq(mbc->pcf, mbc_irq_handlers[i],
  					pcf50633_mbc_irq_handler, mbc);

  	psy_cfg.supplied_to		= mbc->pcf->pdata->batteries;
  	psy_cfg.num_supplicants		= mbc->pcf->pdata->num_batteries;

  	psy_cfg.drv_data		= mbc;

  	/* Create power supplies */

  	mbc->adapter = power_supply_register(&pdev->dev,
  					     &pcf50633_mbc_adapter_desc,
  					     &psy_cfg);
  	if (IS_ERR(mbc->adapter)) {

  		dev_err(mbc->pcf->dev, "failed to register adapter
  ");

  		ret = PTR_ERR(mbc->adapter);

  		return ret;
  	}

  	mbc->usb = power_supply_register(&pdev->dev, &pcf50633_mbc_usb_desc,
  					 &psy_cfg);
  	if (IS_ERR(mbc->usb)) {

  		dev_err(mbc->pcf->dev, "failed to register usb
  ");

  		power_supply_unregister(mbc->adapter);
  		ret = PTR_ERR(mbc->usb);

  		return ret;
  	}

  	mbc->ac = power_supply_register(&pdev->dev, &pcf50633_mbc_ac_desc,
  					&psy_cfg);
  	if (IS_ERR(mbc->ac)) {

  		dev_err(mbc->pcf->dev, "failed to register ac
  ");

  		power_supply_unregister(mbc->adapter);
  		power_supply_unregister(mbc->usb);
  		ret = PTR_ERR(mbc->ac);

  		return ret;
  	}

  	ret = sysfs_create_group(&pdev->dev.kobj, &mbc_attr_group);
  	if (ret)
  		dev_err(mbc->pcf->dev, "failed to create sysfs entries
  ");
  
  	mbcs1 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS1);
  	if (mbcs1 & PCF50633_MBCS1_USBPRES)
  		pcf50633_mbc_irq_handler(PCF50633_IRQ_USBINS, mbc);
  	if (mbcs1 & PCF50633_MBCS1_ADAPTPRES)
  		pcf50633_mbc_irq_handler(PCF50633_IRQ_ADPINS, mbc);
  
  	return 0;
  }

  static int pcf50633_mbc_remove(struct platform_device *pdev)

  {
  	struct pcf50633_mbc *mbc = platform_get_drvdata(pdev);
  	int i;
  
  	/* Remove IRQ handlers */
  	for (i = 0; i < ARRAY_SIZE(mbc_irq_handlers); i++)
  		pcf50633_free_irq(mbc->pcf, mbc_irq_handlers[i]);

  	sysfs_remove_group(&pdev->dev.kobj, &mbc_attr_group);

  	power_supply_unregister(mbc->usb);
  	power_supply_unregister(mbc->adapter);
  	power_supply_unregister(mbc->ac);

  	return 0;
  }
  
  static struct platform_driver pcf50633_mbc_driver = {
  	.driver = {
  		.name = "pcf50633-mbc",
  	},
  	.probe = pcf50633_mbc_probe,

  	.remove = pcf50633_mbc_remove,

  };

  module_platform_driver(pcf50633_mbc_driver);

  
  MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
  MODULE_DESCRIPTION("PCF50633 mbc driver");
  MODULE_LICENSE("GPL");
  MODULE_ALIAS("platform:pcf50633-mbc");