drivers/regulator/dummy.c

   1 /*
   2  * dummy.c
   3  *
   4  * Copyright 2010 Wolfson Microelectronics PLC.
   5  *
   6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of the
  11  * License, or (at your option) any later version.
  12  *
  13  * This is useful for systems with mixed controllable and
  14  * non-controllable regulators, as well as for allowing testing on
  15  * systems with no controllable regulators.
  16  */
  17
  18 #include <linux/err.h>
  19 #include <linux/export.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/regulator/driver.h>
  22 #include <linux/regulator/machine.h>
  23
  24 #include "dummy.h"
  25
  26 struct regulator_dev *dummy_regulator_rdev;
  27
  28 static struct regulator_init_data dummy_initdata = {
  29         .constraints = {
  30                 .always_on = 1,
  31         },
  32 };
  33
  34 static struct regulator_ops dummy_ops;
  35
  36 static const struct regulator_desc dummy_desc = {
  37         .name = "regulator-dummy",
  38         .id = -1,
  39         .type = REGULATOR_VOLTAGE,
  40         .owner = THIS_MODULE,
  41         .ops = &dummy_ops,
  42 };
  43
  44 static int dummy_regulator_probe(struct platform_device *pdev)
  45 {
  46         struct regulator_config config = { };
  47         int ret;
  48
  49         config.dev = &pdev->dev;
  50         config.init_data = &dummy_initdata;
  51
  52         dummy_regulator_rdev = regulator_register(&dummy_desc, &config);
  53         if (IS_ERR(dummy_regulator_rdev)) {
  54                 ret = PTR_ERR(dummy_regulator_rdev);
  55                 pr_err("Failed to register regulator: %d\n", ret);
  56                 return ret;
  57         }
  58
  59         return 0;
  60 }
  61
  62 static struct platform_driver dummy_regulator_driver = {
  63         .probe          = dummy_regulator_probe,
  64         .driver         = {
  65                 .name           = "reg-dummy",
  66         },
  67 };
  68
  69 static struct platform_device *dummy_pdev;
  70
  71 void __init regulator_dummy_init(void)
  72 {
  73         int ret;
  74
  75         dummy_pdev = platform_device_alloc("reg-dummy", -1);
  76         if (!dummy_pdev) {
  77                 pr_err("Failed to allocate dummy regulator device\n");
  78                 return;
  79         }
  80
  81         ret = platform_device_add(dummy_pdev);
  82         if (ret != 0) {
  83                 pr_err("Failed to register dummy regulator device: %d\n", ret);
  84                 platform_device_put(dummy_pdev);
  85                 return;
  86         }
  87
  88         ret = platform_driver_register(&dummy_regulator_driver);
  89         if (ret != 0) {
  90                 pr_err("Failed to register dummy regulator driver: %d\n", ret);
  91                 platform_device_unregister(dummy_pdev);
  92         }
  93 }