/*
   * rfkill-regulator.c - Regulator consumer driver for rfkill
   *
   * Copyright (C) 2009  Guiming Zhuo <gmzhuo@gmail.com>
   * Copyright (C) 2011  Antonio Ospite <ospite@studenti.unina.it>
   *
   * Implementation inspired by leds-regulator driver.
   *
   * 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/module.h>
  #include <linux/err.h>
  #include <linux/of_irq.h>
  #include <linux/slab.h>
  #include <linux/platform_device.h>
  #include <linux/regulator/consumer.h>
  #include <linux/rfkill.h>
  #include <linux/rfkill-regulator.h>
  
  struct rfkill_regulator_data {
  	struct rfkill *rf_kill;
  	bool reg_enabled;
  
  	struct regulator *vcc;
  };
  
  static int rfkill_regulator_set_block(void *data, bool blocked)
  {
  	struct rfkill_regulator_data *rfkill_data = data;
  	int ret = 0;
  
  	pr_debug("%s: blocked: %d
  ", __func__, blocked);
  
  	if (blocked) {
  		if (rfkill_data->reg_enabled) {
  			regulator_disable(rfkill_data->vcc);
  			rfkill_data->reg_enabled = false;
  		}
  	} else {
  		if (!rfkill_data->reg_enabled) {
  			ret = regulator_enable(rfkill_data->vcc);
  			if (!ret)
  				rfkill_data->reg_enabled = true;
  		}
  	}
  
  	pr_debug("%s: regulator_is_enabled after set_block: %d
  ", __func__,
  		regulator_is_enabled(rfkill_data->vcc));
  
  	return ret;
  }
  
  static struct rfkill_ops rfkill_regulator_ops = {
  	.set_block = rfkill_regulator_set_block,
  };
  
  static struct rfkill_regulator_platform_data *rfkill_regulator_get_pdata_from_of(struct device *dev)
  {
  	struct rfkill_regulator_platform_data *pdata;
  	struct device_node *np = dev->of_node;
  
  	if (!np) {
  		np = of_find_matching_node(NULL, dev->driver->of_match_table);
  		if (!np) {
  			dev_notice(dev, "device tree node not available
  ");
  			return ERR_PTR(-ENODEV);
  		}
  	}
  
  	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
  	if (!pdata) {
  		dev_err(dev, "can't allocate platform data
  ");
  		return ERR_PTR(-ENODEV);
  	}
  	of_property_read_u32(np, "type", &pdata->type);
  	of_property_read_string(np, "name", &pdata->name);
  	return pdata;
  }
  
  static int rfkill_regulator_probe(struct platform_device *pdev)
  {
  	struct rfkill_regulator_platform_data *pdata = pdev->dev.platform_data;
  	struct rfkill_regulator_platform_data *p = NULL;
  	struct rfkill_regulator_data *rfkill_data;
  	struct regulator *vcc;
  	struct rfkill *rf_kill;
  	int ret = 0;
  
  	if (pdata == NULL) {
  		p = pdata = rfkill_regulator_get_pdata_from_of(&pdev->dev);
  		if (IS_ERR(p)) {
  			dev_err(&pdev->dev, "no platform data
  ");
  			return PTR_ERR(p);
  		}
  	}
  
  	if (pdata->name == NULL || pdata->type == 0) {
  		dev_err(&pdev->dev, "invalid name or type in platform data
  ");
  		ret = -EINVAL;
  		goto out;
  	}
  
  	vcc = regulator_get_exclusive(&pdev->dev, "vrfkill");
  	if (IS_ERR(vcc)) {
  		dev_err(&pdev->dev, "Cannot get vcc for %s
  ", pdata->name);
  		ret = PTR_ERR(vcc);
  		goto out;
  	}
  
  	rfkill_data = kzalloc(sizeof(*rfkill_data), GFP_KERNEL);
  	if (rfkill_data == NULL) {
  		ret = -ENOMEM;
  		goto err_data_alloc;
  	}
  
  	rf_kill = rfkill_alloc(pdata->name, &pdev->dev,
  				pdata->type,
  				&rfkill_regulator_ops, rfkill_data);
  	if (rf_kill == NULL) {
  		ret = -ENOMEM;
  		goto err_rfkill_alloc;
  	}
  
  	if (regulator_is_enabled(vcc)) {
  		dev_dbg(&pdev->dev, "Regulator already enabled
  ");
  		rfkill_data->reg_enabled = true;
  	}
  	rfkill_data->vcc = vcc;
  	rfkill_data->rf_kill = rf_kill;
  
  	ret = rfkill_register(rf_kill);
  	if (ret) {
  		dev_err(&pdev->dev, "Cannot register rfkill device
  ");
  		goto err_rfkill_register;
  	}
  
  	platform_set_drvdata(pdev, rfkill_data);
  	dev_info(&pdev->dev, "%s initialized
  ", pdata->name);
  	kfree(p);
  	return 0;
  
  err_rfkill_register:
  	rfkill_destroy(rf_kill);
  err_rfkill_alloc:
  	kfree(rfkill_data);
  err_data_alloc:
  	regulator_put(vcc);
  out:
  	kfree(p);
  	return ret;
  }
  
  static int rfkill_regulator_remove(struct platform_device *pdev)
  {
  	struct rfkill_regulator_data *rfkill_data = platform_get_drvdata(pdev);
  	struct rfkill *rf_kill = rfkill_data->rf_kill;
  
  	rfkill_unregister(rf_kill);
  	rfkill_destroy(rf_kill);
  	regulator_put(rfkill_data->vcc);
  	kfree(rfkill_data);
  
  	return 0;
  }
  
  static const struct of_device_id rfkill_regulator_of_match_table[] = {
  	{ .compatible = "net,rfkill-reg" },
  	{ }
  };
  MODULE_DEVICE_TABLE(of, rfkill_regulator_of_match_table);
  
  static struct platform_driver rfkill_regulator_driver = {
  	.probe = rfkill_regulator_probe,
  	.remove = rfkill_regulator_remove,
  	.driver = {
  		.name = "rfkill-regulator",
  		.owner = THIS_MODULE,
  		.of_match_table = of_match_ptr(rfkill_regulator_of_match_table),
  	},
  };
  
  module_platform_driver(rfkill_regulator_driver);
  
  MODULE_AUTHOR("Guiming Zhuo <gmzhuo@gmail.com>");
  MODULE_AUTHOR("Antonio Ospite <ospite@studenti.unina.it>");
  MODULE_DESCRIPTION("Regulator consumer driver for rfkill");
  MODULE_LICENSE("GPL");
  MODULE_ALIAS("platform:rfkill-regulator");