/*
   *  acpi_ac.c - ACPI AC Adapter Driver ($Revision: 27 $)
   *
   *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.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; either version 2 of the License, or (at
   *  your option) any later version.
   *
   *  This program is distributed in the hope that it will be useful, but
   *  WITHOUT ANY WARRANTY; 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/module.h>

  #include <linux/slab.h>

  #include <linux/init.h>
  #include <linux/types.h>

  #include <linux/dmi.h>
  #include <linux/delay.h>

  #ifdef CONFIG_ACPI_PROCFS_POWER
  #include <linux/proc_fs.h>
  #include <linux/seq_file.h>
  #endif

  #include <linux/platform_device.h>

  #include <linux/power_supply.h>

  #include <linux/acpi.h>

  #include "battery.h"

  #define PREFIX "ACPI: "

  #define ACPI_AC_CLASS			"ac_adapter"

  #define ACPI_AC_DEVICE_NAME		"AC Adapter"
  #define ACPI_AC_FILE_STATE		"state"
  #define ACPI_AC_NOTIFY_STATUS		0x80
  #define ACPI_AC_STATUS_OFFLINE		0x00
  #define ACPI_AC_STATUS_ONLINE		0x01
  #define ACPI_AC_STATUS_UNKNOWN		0xFF
  
  #define _COMPONENT		ACPI_AC_COMPONENT

  ACPI_MODULE_NAME("ac");

  MODULE_AUTHOR("Paul Diefenbaugh");

  MODULE_DESCRIPTION("ACPI AC Adapter Driver");

  MODULE_LICENSE("GPL");

  static int acpi_ac_add(struct acpi_device *device);
  static int acpi_ac_remove(struct acpi_device *device);
  static void acpi_ac_notify(struct acpi_device *device, u32 event);
  
  static const struct acpi_device_id ac_device_ids[] = {
  	{"ACPI0003", 0},
  	{"", 0},
  };
  MODULE_DEVICE_TABLE(acpi, ac_device_ids);
  
  #ifdef CONFIG_PM_SLEEP
  static int acpi_ac_resume(struct device *dev);
  #endif
  static SIMPLE_DEV_PM_OPS(acpi_ac_pm, NULL, acpi_ac_resume);

  #ifdef CONFIG_ACPI_PROCFS_POWER
  extern struct proc_dir_entry *acpi_lock_ac_dir(void);
  extern void *acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
  static int acpi_ac_open_fs(struct inode *inode, struct file *file);
  #endif

  static int ac_sleep_before_get_state_ms;

  static struct acpi_driver acpi_ac_driver = {
  	.name = "ac",
  	.class = ACPI_AC_CLASS,
  	.ids = ac_device_ids,
  	.flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
  	.ops = {
  		.add = acpi_ac_add,
  		.remove = acpi_ac_remove,
  		.notify = acpi_ac_notify,
  		},
  	.drv.pm = &acpi_ac_pm,
  };

  struct acpi_ac {

  	struct power_supply *charger;
  	struct power_supply_desc charger_desc;

  	struct acpi_device * device;

  	unsigned long long state;

  	struct notifier_block battery_nb;

  };

  #define to_acpi_ac(x) power_supply_get_drvdata(x)

  #ifdef CONFIG_ACPI_PROCFS_POWER
  static const struct file_operations acpi_ac_fops = {
  	.owner = THIS_MODULE,
  	.open = acpi_ac_open_fs,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  };
  #endif

  /* --------------------------------------------------------------------------
                                 AC Adapter Management
     -------------------------------------------------------------------------- */

  static int acpi_ac_get_state(struct acpi_ac *ac)

  {

  	acpi_status status = AE_OK;
  
  	if (!ac)
  		return -EINVAL;

  	status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL,

  				       &ac->state);

  	if (ACPI_FAILURE(status)) {

  		ACPI_EXCEPTION((AE_INFO, status,
  				"Error reading AC Adapter state"));

  		ac->state = ACPI_AC_STATUS_UNKNOWN;

  		return -ENODEV;

  	}

  	return 0;

  }

  /* --------------------------------------------------------------------------
                              sysfs I/F
     -------------------------------------------------------------------------- */
  static int get_ac_property(struct power_supply *psy,
  			   enum power_supply_property psp,
  			   union power_supply_propval *val)
  {
  	struct acpi_ac *ac = to_acpi_ac(psy);
  
  	if (!ac)
  		return -ENODEV;
  
  	if (acpi_ac_get_state(ac))
  		return -ENODEV;
  
  	switch (psp) {
  	case POWER_SUPPLY_PROP_ONLINE:
  		val->intval = ac->state;
  		break;
  	default:
  		return -EINVAL;
  	}
  	return 0;
  }
  
  static enum power_supply_property ac_props[] = {
  	POWER_SUPPLY_PROP_ONLINE,
  };

  #ifdef CONFIG_ACPI_PROCFS_POWER
  /* --------------------------------------------------------------------------
                                FS Interface (/proc)
     -------------------------------------------------------------------------- */
  
  static struct proc_dir_entry *acpi_ac_dir;
  
  static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
  {
  	struct acpi_ac *ac = seq->private;
  
  
  	if (!ac)
  		return 0;
  
  	if (acpi_ac_get_state(ac)) {
  		seq_puts(seq, "ERROR: Unable to read AC Adapter state
  ");
  		return 0;
  	}
  
  	seq_puts(seq, "state:                   ");
  	switch (ac->state) {
  	case ACPI_AC_STATUS_OFFLINE:
  		seq_puts(seq, "off-line
  ");
  		break;
  	case ACPI_AC_STATUS_ONLINE:
  		seq_puts(seq, "on-line
  ");
  		break;
  	default:
  		seq_puts(seq, "unknown
  ");
  		break;
  	}
  
  	return 0;
  }
  
  static int acpi_ac_open_fs(struct inode *inode, struct file *file)
  {
  	return single_open(file, acpi_ac_seq_show, PDE_DATA(inode));
  }
  
  static int acpi_ac_add_fs(struct acpi_ac *ac)
  {
  	struct proc_dir_entry *entry = NULL;
  
  	printk(KERN_WARNING PREFIX "Deprecated procfs I/F for AC is loaded,"
  			" please retry with CONFIG_ACPI_PROCFS_POWER cleared
  ");
  	if (!acpi_device_dir(ac->device)) {
  		acpi_device_dir(ac->device) =
  			proc_mkdir(acpi_device_bid(ac->device), acpi_ac_dir);
  		if (!acpi_device_dir(ac->device))
  			return -ENODEV;
  	}
  
  	/* 'state' [R] */
  	entry = proc_create_data(ACPI_AC_FILE_STATE,
  				 S_IRUGO, acpi_device_dir(ac->device),
  				 &acpi_ac_fops, ac);
  	if (!entry)
  		return -ENODEV;
  	return 0;
  }
  
  static int acpi_ac_remove_fs(struct acpi_ac *ac)
  {
  
  	if (acpi_device_dir(ac->device)) {
  		remove_proc_entry(ACPI_AC_FILE_STATE,
  				  acpi_device_dir(ac->device));
  		remove_proc_entry(acpi_device_bid(ac->device), acpi_ac_dir);
  		acpi_device_dir(ac->device) = NULL;
  	}
  
  	return 0;
  }
  #endif

  /* --------------------------------------------------------------------------
                                     Driver Model
     -------------------------------------------------------------------------- */

  static void acpi_ac_notify(struct acpi_device *device, u32 event)

  {

  	struct acpi_ac *ac = acpi_driver_data(device);

  
  	if (!ac)

  		return;

  	switch (event) {

  	default:
  		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
  				  "Unsupported event [0x%x]
  ", event));

  	case ACPI_AC_NOTIFY_STATUS:

  	case ACPI_NOTIFY_BUS_CHECK:
  	case ACPI_NOTIFY_DEVICE_CHECK:

  		/*
  		 * A buggy BIOS may notify AC first and then sleep for
  		 * a specific time before doing actual operations in the
  		 * EC event handler (_Qxx). This will cause the AC state
  		 * reported by the ACPI event to be incorrect, so wait for a
  		 * specific time for the EC event handler to make progress.
  		 */
  		if (ac_sleep_before_get_state_ms > 0)
  			msleep(ac_sleep_before_get_state_ms);

  		acpi_ac_get_state(ac);

  		acpi_bus_generate_netlink_event(device->pnp.device_class,
  						  dev_name(&device->dev), event,
  						  (u32) ac->state);
  		acpi_notifier_call_chain(device, event, (u32) ac->state);

  		kobject_uevent(&ac->charger->dev.kobj, KOBJ_CHANGE);

  	}

  	return;

  }

  static int acpi_ac_battery_notify(struct notifier_block *nb,
  				  unsigned long action, void *data)
  {
  	struct acpi_ac *ac = container_of(nb, struct acpi_ac, battery_nb);
  	struct acpi_bus_event *event = (struct acpi_bus_event *)data;
  
  	/*
  	 * On HP Pavilion dv6-6179er AC status notifications aren't triggered
  	 * when adapter is plugged/unplugged. However, battery status
  	 * notifcations are triggered when battery starts charging or
  	 * discharging. Re-reading AC status triggers lost AC notifications,
  	 * if AC status has changed.
  	 */
  	if (strcmp(event->device_class, ACPI_BATTERY_CLASS) == 0 &&
  	    event->type == ACPI_BATTERY_NOTIFY_STATUS)
  		acpi_ac_get_state(ac);
  
  	return NOTIFY_OK;
  }

  static int thinkpad_e530_quirk(const struct dmi_system_id *d)
  {
  	ac_sleep_before_get_state_ms = 1000;
  	return 0;
  }

  static const struct dmi_system_id ac_dmi_table[] = {

  	{
  	.callback = thinkpad_e530_quirk,
  	.ident = "thinkpad e530",
  	.matches = {
  		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
  		DMI_MATCH(DMI_PRODUCT_NAME, "32597CG"),
  		},
  	},
  	{},
  };

  static int acpi_ac_add(struct acpi_device *device)

  {

  	struct power_supply_config psy_cfg = {};

  	int result = 0;

  	struct acpi_ac *ac = NULL;

  	if (!device)
  		return -EINVAL;

  	ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);

  	if (!ac)

  		return -ENOMEM;

  	ac->device = device;
  	strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
  	strcpy(acpi_device_class(device), ACPI_AC_CLASS);
  	device->driver_data = ac;

  
  	result = acpi_ac_get_state(ac);
  	if (result)
  		goto end;

  	psy_cfg.drv_data = ac;
  
  	ac->charger_desc.name = acpi_device_bid(device);

  #ifdef CONFIG_ACPI_PROCFS_POWER
  	result = acpi_ac_add_fs(ac);
  	if (result)
  		goto end;
  #endif

  	ac->charger_desc.type = POWER_SUPPLY_TYPE_MAINS;
  	ac->charger_desc.properties = ac_props;
  	ac->charger_desc.num_properties = ARRAY_SIZE(ac_props);
  	ac->charger_desc.get_property = get_ac_property;
  	ac->charger = power_supply_register(&ac->device->dev,
  					    &ac->charger_desc, &psy_cfg);
  	if (IS_ERR(ac->charger)) {
  		result = PTR_ERR(ac->charger);

  		goto end;

  	}

  	printk(KERN_INFO PREFIX "%s [%s] (%s)
  ",

  	       acpi_device_name(device), acpi_device_bid(device),

  	       ac->state ? "on-line" : "off-line");

  	ac->battery_nb.notifier_call = acpi_ac_battery_notify;
  	register_acpi_notifier(&ac->battery_nb);

  end:

  	if (result) {
  #ifdef CONFIG_ACPI_PROCFS_POWER
  		acpi_ac_remove_fs(ac);
  #endif

  		kfree(ac);

  	}

  	dmi_check_system(ac_dmi_table);

  	return result;

  }

  #ifdef CONFIG_PM_SLEEP

  static int acpi_ac_resume(struct device *dev)

  {
  	struct acpi_ac *ac;
  	unsigned old_state;

  
  	if (!dev)
  		return -EINVAL;

  	ac = acpi_driver_data(to_acpi_device(dev));

  	if (!ac)

  		return -EINVAL;

  	old_state = ac->state;
  	if (acpi_ac_get_state(ac))
  		return 0;
  	if (old_state != ac->state)

  		kobject_uevent(&ac->charger->dev.kobj, KOBJ_CHANGE);

  	return 0;
  }

  #else
  #define acpi_ac_resume NULL

  #endif

  static int acpi_ac_remove(struct acpi_device *device)

  {

  	struct acpi_ac *ac = NULL;

  	if (!device || !acpi_driver_data(device))

  		return -EINVAL;

  	ac = acpi_driver_data(device);

  	power_supply_unregister(ac->charger);

  	unregister_acpi_notifier(&ac->battery_nb);

  #ifdef CONFIG_ACPI_PROCFS_POWER
  	acpi_ac_remove_fs(ac);
  #endif

  	kfree(ac);

  	return 0;

  }

  static int __init acpi_ac_init(void)

  {

  	int result;

  	if (acpi_disabled)
  		return -ENODEV;

  #ifdef CONFIG_ACPI_PROCFS_POWER
  	acpi_ac_dir = acpi_lock_ac_dir();
  	if (!acpi_ac_dir)
  		return -ENODEV;
  #endif

  	result = acpi_bus_register_driver(&acpi_ac_driver);

  	if (result < 0) {
  #ifdef CONFIG_ACPI_PROCFS_POWER
  		acpi_unlock_ac_dir(acpi_ac_dir);
  #endif

  		return -ENODEV;

  	}

  	return 0;

  }

  static void __exit acpi_ac_exit(void)

  {

  	acpi_bus_unregister_driver(&acpi_ac_driver);

  #ifdef CONFIG_ACPI_PROCFS_POWER
  	acpi_unlock_ac_dir(acpi_ac_dir);
  #endif

  }

  module_init(acpi_ac_init);
  module_exit(acpi_ac_exit);