// SPDX-License-Identifier: GPL-2.0-or-later

  /*
   * dummy.c
   *
   * Copyright 2010 Wolfson Microelectronics PLC.
   *
   * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   *

   * This is useful for systems with mixed controllable and
   * non-controllable regulators, as well as for allowing testing on
   * systems with no controllable regulators.
   */
  
  #include <linux/err.h>

  #include <linux/export.h>

  #include <linux/platform_device.h>
  #include <linux/regulator/driver.h>
  #include <linux/regulator/machine.h>
  
  #include "dummy.h"
  
  struct regulator_dev *dummy_regulator_rdev;

  static const struct regulator_init_data dummy_initdata = {

  	.constraints = {
  		.always_on = 1,
  	},
  };

  static const struct regulator_ops dummy_ops;

  static const struct regulator_desc dummy_desc = {

  	.name = "regulator-dummy",

  	.id = -1,
  	.type = REGULATOR_VOLTAGE,
  	.owner = THIS_MODULE,
  	.ops = &dummy_ops,
  };

  static int dummy_regulator_probe(struct platform_device *pdev)

  {

  	struct regulator_config config = { };

  	int ret;

  	config.dev = &pdev->dev;

  	config.init_data = &dummy_initdata;
  
  	dummy_regulator_rdev = regulator_register(&dummy_desc, &config);

  	if (IS_ERR(dummy_regulator_rdev)) {
  		ret = PTR_ERR(dummy_regulator_rdev);
  		pr_err("Failed to register regulator: %d
  ", ret);
  		return ret;
  	}
  
  	return 0;
  }
  
  static struct platform_driver dummy_regulator_driver = {
  	.probe		= dummy_regulator_probe,
  	.driver		= {
  		.name		= "reg-dummy",

  	},
  };

  static struct platform_device *dummy_pdev;
  
  void __init regulator_dummy_init(void)
  {
  	int ret;
  
  	dummy_pdev = platform_device_alloc("reg-dummy", -1);
  	if (!dummy_pdev) {
  		pr_err("Failed to allocate dummy regulator device
  ");
  		return;
  	}
  
  	ret = platform_device_add(dummy_pdev);
  	if (ret != 0) {
  		pr_err("Failed to register dummy regulator device: %d
  ", ret);
  		platform_device_put(dummy_pdev);
  		return;
  	}

  	ret = platform_driver_register(&dummy_regulator_driver);
  	if (ret != 0) {
  		pr_err("Failed to register dummy regulator driver: %d
  ", ret);

  		platform_device_unregister(dummy_pdev);

  	}
  }