/*
   * Battery and Power Management code for the Sharp SL-6000x
   *
   * Copyright (c) 2005 Dirk Opfer
   * Copyright (c) 2008 Dmitry Baryshkov
   *
   * 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/power_supply.h>
  #include <linux/wm97xx.h>
  #include <linux/delay.h>
  #include <linux/spinlock.h>
  #include <linux/interrupt.h>
  #include <linux/gpio.h>
  
  #include <asm/mach-types.h>
  #include <mach/tosa.h>
  
  static DEFINE_MUTEX(bat_lock); /* protects gpio pins */
  static struct work_struct bat_work;
  
  struct tosa_bat {
  	int status;
  	struct power_supply psy;
  	int full_chrg;
  
  	struct mutex work_lock; /* protects data */
  
  	bool (*is_present)(struct tosa_bat *bat);
  	int gpio_full;
  	int gpio_charge_off;
  
  	int technology;
  
  	int gpio_bat;
  	int adc_bat;
  	int adc_bat_divider;
  	int bat_max;
  	int bat_min;
  
  	int gpio_temp;
  	int adc_temp;
  	int adc_temp_divider;
  };
  
  static struct tosa_bat tosa_bat_main;
  static struct tosa_bat tosa_bat_jacket;
  
  static unsigned long tosa_read_bat(struct tosa_bat *bat)
  {
  	unsigned long value = 0;
  
  	if (bat->gpio_bat < 0 || bat->adc_bat < 0)
  		return 0;
  
  	mutex_lock(&bat_lock);
  	gpio_set_value(bat->gpio_bat, 1);
  	msleep(5);
  	value = wm97xx_read_aux_adc(dev_get_drvdata(bat->psy.dev->parent),
  			bat->adc_bat);
  	gpio_set_value(bat->gpio_bat, 0);
  	mutex_unlock(&bat_lock);
  
  	value = value * 1000000 / bat->adc_bat_divider;
  
  	return value;
  }
  
  static unsigned long tosa_read_temp(struct tosa_bat *bat)
  {
  	unsigned long value = 0;
  
  	if (bat->gpio_temp < 0 || bat->adc_temp < 0)
  		return 0;
  
  	mutex_lock(&bat_lock);
  	gpio_set_value(bat->gpio_temp, 1);
  	msleep(5);
  	value = wm97xx_read_aux_adc(dev_get_drvdata(bat->psy.dev->parent),
  			bat->adc_temp);
  	gpio_set_value(bat->gpio_temp, 0);
  	mutex_unlock(&bat_lock);
  
  	value = value * 10000 / bat->adc_temp_divider;
  
  	return value;
  }
  
  static int tosa_bat_get_property(struct power_supply *psy,
  			    enum power_supply_property psp,
  			    union power_supply_propval *val)
  {
  	int ret = 0;
  	struct tosa_bat *bat = container_of(psy, struct tosa_bat, psy);
  
  	if (bat->is_present && !bat->is_present(bat)
  			&& psp != POWER_SUPPLY_PROP_PRESENT) {
  		return -ENODEV;
  	}
  
  	switch (psp) {
  	case POWER_SUPPLY_PROP_STATUS:
  		val->intval = bat->status;
  		break;
  	case POWER_SUPPLY_PROP_TECHNOLOGY:
  		val->intval = bat->technology;
  		break;
  	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
  		val->intval = tosa_read_bat(bat);
  		break;
  	case POWER_SUPPLY_PROP_VOLTAGE_MAX:
  		if (bat->full_chrg == -1)
  			val->intval = bat->bat_max;
  		else
  			val->intval = bat->full_chrg;
  		break;
  	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
  		val->intval = bat->bat_max;
  		break;
  	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
  		val->intval = bat->bat_min;
  		break;
  	case POWER_SUPPLY_PROP_TEMP:
  		val->intval = tosa_read_temp(bat);
  		break;
  	case POWER_SUPPLY_PROP_PRESENT:
  		val->intval = bat->is_present ? bat->is_present(bat) : 1;
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  	return ret;
  }
  
  static bool tosa_jacket_bat_is_present(struct tosa_bat *bat)
  {
  	return gpio_get_value(TOSA_GPIO_JACKET_DETECT) == 0;
  }
  
  static void tosa_bat_external_power_changed(struct power_supply *psy)
  {
  	schedule_work(&bat_work);
  }
  
  static irqreturn_t tosa_bat_gpio_isr(int irq, void *data)
  {
  	pr_info("tosa_bat_gpio irq
  ");
  	schedule_work(&bat_work);
  	return IRQ_HANDLED;
  }
  
  static void tosa_bat_update(struct tosa_bat *bat)
  {
  	int old;
  	struct power_supply *psy = &bat->psy;
  
  	mutex_lock(&bat->work_lock);
  
  	old = bat->status;
  
  	if (bat->is_present && !bat->is_present(bat)) {
  		printk(KERN_NOTICE "%s not present
  ", psy->name);
  		bat->status = POWER_SUPPLY_STATUS_UNKNOWN;
  		bat->full_chrg = -1;
  	} else if (power_supply_am_i_supplied(psy)) {
  		if (bat->status == POWER_SUPPLY_STATUS_DISCHARGING) {
  			gpio_set_value(bat->gpio_charge_off, 0);
  			mdelay(15);
  		}
  
  		if (gpio_get_value(bat->gpio_full)) {
  			if (old == POWER_SUPPLY_STATUS_CHARGING ||
  					bat->full_chrg == -1)
  				bat->full_chrg = tosa_read_bat(bat);
  
  			gpio_set_value(bat->gpio_charge_off, 1);
  			bat->status = POWER_SUPPLY_STATUS_FULL;
  		} else {
  			gpio_set_value(bat->gpio_charge_off, 0);
  			bat->status = POWER_SUPPLY_STATUS_CHARGING;
  		}
  	} else {
  		gpio_set_value(bat->gpio_charge_off, 1);
  		bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
  	}
  
  	if (old != bat->status)
  		power_supply_changed(psy);
  
  	mutex_unlock(&bat->work_lock);
  }
  
  static void tosa_bat_work(struct work_struct *work)
  {
  	tosa_bat_update(&tosa_bat_main);
  	tosa_bat_update(&tosa_bat_jacket);
  }
  
  
  static enum power_supply_property tosa_bat_main_props[] = {
  	POWER_SUPPLY_PROP_STATUS,
  	POWER_SUPPLY_PROP_TECHNOLOGY,
  	POWER_SUPPLY_PROP_VOLTAGE_NOW,
  	POWER_SUPPLY_PROP_VOLTAGE_MAX,
  	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
  	POWER_SUPPLY_PROP_TEMP,
  	POWER_SUPPLY_PROP_PRESENT,
  };
  
  static enum power_supply_property tosa_bat_bu_props[] = {
  	POWER_SUPPLY_PROP_STATUS,
  	POWER_SUPPLY_PROP_TECHNOLOGY,
  	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
  	POWER_SUPPLY_PROP_VOLTAGE_NOW,
  	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
  	POWER_SUPPLY_PROP_PRESENT,
  };
  
  static struct tosa_bat tosa_bat_main = {
  	.status = POWER_SUPPLY_STATUS_DISCHARGING,
  	.full_chrg = -1,
  	.psy = {
  		.name		= "main-battery",
  		.type		= POWER_SUPPLY_TYPE_BATTERY,
  		.properties	= tosa_bat_main_props,
  		.num_properties	= ARRAY_SIZE(tosa_bat_main_props),
  		.get_property	= tosa_bat_get_property,
  		.external_power_changed = tosa_bat_external_power_changed,
  		.use_for_apm	= 1,
  	},
  
  	.gpio_full = TOSA_GPIO_BAT0_CRG,
  	.gpio_charge_off = TOSA_GPIO_CHARGE_OFF,
  
  	.technology = POWER_SUPPLY_TECHNOLOGY_LIPO,
  
  	.gpio_bat = TOSA_GPIO_BAT0_V_ON,
  	.adc_bat = WM97XX_AUX_ID3,
  	.adc_bat_divider = 414,
  	.bat_max = 4310000,
  	.bat_min = 1551 * 1000000 / 414,
  
  	.gpio_temp = TOSA_GPIO_BAT1_TH_ON,
  	.adc_temp = WM97XX_AUX_ID2,
  	.adc_temp_divider = 10000,
  };
  
  static struct tosa_bat tosa_bat_jacket = {
  	.status = POWER_SUPPLY_STATUS_DISCHARGING,
  	.full_chrg = -1,
  	.psy = {
  		.name		= "jacket-battery",
  		.type		= POWER_SUPPLY_TYPE_BATTERY,
  		.properties	= tosa_bat_main_props,
  		.num_properties	= ARRAY_SIZE(tosa_bat_main_props),
  		.get_property	= tosa_bat_get_property,
  		.external_power_changed = tosa_bat_external_power_changed,
  	},
  
  	.is_present = tosa_jacket_bat_is_present,
  	.gpio_full = TOSA_GPIO_BAT1_CRG,
  	.gpio_charge_off = TOSA_GPIO_CHARGE_OFF_JC,
  
  	.technology = POWER_SUPPLY_TECHNOLOGY_LIPO,
  
  	.gpio_bat = TOSA_GPIO_BAT1_V_ON,
  	.adc_bat = WM97XX_AUX_ID3,
  	.adc_bat_divider = 414,
  	.bat_max = 4310000,
  	.bat_min = 1551 * 1000000 / 414,
  
  	.gpio_temp = TOSA_GPIO_BAT0_TH_ON,
  	.adc_temp = WM97XX_AUX_ID2,
  	.adc_temp_divider = 10000,
  };
  
  static struct tosa_bat tosa_bat_bu = {
  	.status = POWER_SUPPLY_STATUS_UNKNOWN,
  	.full_chrg = -1,
  
  	.psy = {
  		.name		= "backup-battery",
  		.type		= POWER_SUPPLY_TYPE_BATTERY,
  		.properties	= tosa_bat_bu_props,
  		.num_properties	= ARRAY_SIZE(tosa_bat_bu_props),
  		.get_property	= tosa_bat_get_property,
  		.external_power_changed = tosa_bat_external_power_changed,
  	},
  
  	.gpio_full = -1,
  	.gpio_charge_off = -1,
  
  	.technology = POWER_SUPPLY_TECHNOLOGY_LiMn,
  
  	.gpio_bat = TOSA_GPIO_BU_CHRG_ON,
  	.adc_bat = WM97XX_AUX_ID4,
  	.adc_bat_divider = 1266,
  
  	.gpio_temp = -1,
  	.adc_temp = -1,
  	.adc_temp_divider = -1,
  };
  
  static struct gpio tosa_bat_gpios[] = {
  	{ TOSA_GPIO_CHARGE_OFF,	   GPIOF_OUT_INIT_HIGH, "main charge off" },
  	{ TOSA_GPIO_CHARGE_OFF_JC, GPIOF_OUT_INIT_HIGH, "jacket charge off" },
  	{ TOSA_GPIO_BAT_SW_ON,	   GPIOF_OUT_INIT_LOW,	"battery switch" },
  	{ TOSA_GPIO_BAT0_V_ON,	   GPIOF_OUT_INIT_LOW,	"main battery" },
  	{ TOSA_GPIO_BAT1_V_ON,	   GPIOF_OUT_INIT_LOW,	"jacket battery" },
  	{ TOSA_GPIO_BAT1_TH_ON,	   GPIOF_OUT_INIT_LOW,	"main battery temp" },
  	{ TOSA_GPIO_BAT0_TH_ON,	   GPIOF_OUT_INIT_LOW,	"jacket battery temp" },
  	{ TOSA_GPIO_BU_CHRG_ON,	   GPIOF_OUT_INIT_LOW,	"backup battery" },
  	{ TOSA_GPIO_BAT0_CRG,	   GPIOF_IN,		"main battery full" },
  	{ TOSA_GPIO_BAT1_CRG,	   GPIOF_IN,		"jacket battery full" },
  	{ TOSA_GPIO_BAT0_LOW,	   GPIOF_IN,		"main battery low" },
  	{ TOSA_GPIO_BAT1_LOW,	   GPIOF_IN,		"jacket battery low" },
  	{ TOSA_GPIO_JACKET_DETECT, GPIOF_IN,		"jacket detect" },
  };
  
  #ifdef CONFIG_PM
  static int tosa_bat_suspend(struct platform_device *dev, pm_message_t state)
  {
  	/* flush all pending status updates */
  	flush_work(&bat_work);
  	return 0;
  }
  
  static int tosa_bat_resume(struct platform_device *dev)
  {
  	/* things may have changed while we were away */
  	schedule_work(&bat_work);
  	return 0;
  }
  #else
  #define tosa_bat_suspend NULL
  #define tosa_bat_resume NULL
  #endif
  
  static int tosa_bat_probe(struct platform_device *dev)
  {
  	int ret;
  
  	if (!machine_is_tosa())
  		return -ENODEV;
  
  	ret = gpio_request_array(tosa_bat_gpios, ARRAY_SIZE(tosa_bat_gpios));
  	if (ret)
  		return ret;
  
  	mutex_init(&tosa_bat_main.work_lock);
  	mutex_init(&tosa_bat_jacket.work_lock);
  
  	INIT_WORK(&bat_work, tosa_bat_work);
  
  	ret = power_supply_register(&dev->dev, &tosa_bat_main.psy);
  	if (ret)
  		goto err_psy_reg_main;
  	ret = power_supply_register(&dev->dev, &tosa_bat_jacket.psy);
  	if (ret)
  		goto err_psy_reg_jacket;
  	ret = power_supply_register(&dev->dev, &tosa_bat_bu.psy);
  	if (ret)
  		goto err_psy_reg_bu;
  
  	ret = request_irq(gpio_to_irq(TOSA_GPIO_BAT0_CRG),
  				tosa_bat_gpio_isr,
  				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
  				"main full", &tosa_bat_main);
  	if (ret)
  		goto err_req_main;
  
  	ret = request_irq(gpio_to_irq(TOSA_GPIO_BAT1_CRG),
  				tosa_bat_gpio_isr,
  				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
  				"jacket full", &tosa_bat_jacket);
  	if (ret)
  		goto err_req_jacket;
  
  	ret = request_irq(gpio_to_irq(TOSA_GPIO_JACKET_DETECT),
  				tosa_bat_gpio_isr,
  				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
  				"jacket detect", &tosa_bat_jacket);
  	if (!ret) {
  		schedule_work(&bat_work);
  		return 0;
  	}
  
  	free_irq(gpio_to_irq(TOSA_GPIO_BAT1_CRG), &tosa_bat_jacket);
  err_req_jacket:
  	free_irq(gpio_to_irq(TOSA_GPIO_BAT0_CRG), &tosa_bat_main);
  err_req_main:
  	power_supply_unregister(&tosa_bat_bu.psy);
  err_psy_reg_bu:
  	power_supply_unregister(&tosa_bat_jacket.psy);
  err_psy_reg_jacket:
  	power_supply_unregister(&tosa_bat_main.psy);
  err_psy_reg_main:
  
  	/* see comment in tosa_bat_remove */
  	cancel_work_sync(&bat_work);
  
  	gpio_free_array(tosa_bat_gpios, ARRAY_SIZE(tosa_bat_gpios));
  	return ret;
  }
  
  static int tosa_bat_remove(struct platform_device *dev)
  {
  	free_irq(gpio_to_irq(TOSA_GPIO_JACKET_DETECT), &tosa_bat_jacket);
  	free_irq(gpio_to_irq(TOSA_GPIO_BAT1_CRG), &tosa_bat_jacket);
  	free_irq(gpio_to_irq(TOSA_GPIO_BAT0_CRG), &tosa_bat_main);
  
  	power_supply_unregister(&tosa_bat_bu.psy);
  	power_supply_unregister(&tosa_bat_jacket.psy);
  	power_supply_unregister(&tosa_bat_main.psy);
  
  	/*
  	 * Now cancel the bat_work.  We won't get any more schedules,
  	 * since all sources (isr and external_power_changed) are
  	 * unregistered now.
  	 */
  	cancel_work_sync(&bat_work);
  	gpio_free_array(tosa_bat_gpios, ARRAY_SIZE(tosa_bat_gpios));
  	return 0;
  }
  
  static struct platform_driver tosa_bat_driver = {
  	.driver.name	= "wm97xx-battery",
  	.driver.owner	= THIS_MODULE,
  	.probe		= tosa_bat_probe,
  	.remove		= tosa_bat_remove,
  	.suspend	= tosa_bat_suspend,
  	.resume		= tosa_bat_resume,
  };
  
  module_platform_driver(tosa_bat_driver);
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Dmitry Baryshkov");
  MODULE_DESCRIPTION("Tosa battery driver");
  MODULE_ALIAS("platform:wm97xx-battery");