1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * dummy.c
4 *
5 * Copyright 2010 Wolfson Microelectronics PLC.
6 *
7 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
8 *
9 * This is useful for systems with mixed controllable and
10 * non-controllable regulators, as well as for allowing testing on
11 * systems with no controllable regulators.
12 */
13
14#include <linux/err.h>
15#include <linux/export.h>
16#include <linux/platform_device.h>
17#include <linux/regulator/driver.h>
18#include <linux/regulator/machine.h>
19
20#include "dummy.h"
21
22struct regulator_dev *dummy_regulator_rdev;
23
24static const struct regulator_init_data dummy_initdata = {
25	.constraints = {
26		.always_on = 1,
27	},
28};
29
30static const struct regulator_ops dummy_ops;
31
32static const struct regulator_desc dummy_desc = {
33	.name = "regulator-dummy",
34	.id = -1,
35	.type = REGULATOR_VOLTAGE,
36	.owner = THIS_MODULE,
37	.ops = &dummy_ops,
38};
39
40static int dummy_regulator_probe(struct platform_device *pdev)
41{
42	struct regulator_config config = { };
43	int ret;
44
45	config.dev = &pdev->dev;
46	config.init_data = &dummy_initdata;
47
48	dummy_regulator_rdev = regulator_register(&dummy_desc, &config);
49	if (IS_ERR(dummy_regulator_rdev)) {
50		ret = PTR_ERR(dummy_regulator_rdev);
51		pr_err("Failed to register regulator: %d\n", ret);
52		return ret;
53	}
54
55	return 0;
56}
57
58static struct platform_driver dummy_regulator_driver = {
59	.probe		= dummy_regulator_probe,
60	.driver		= {
61		.name		= "reg-dummy",
62	},
63};
64
65static struct platform_device *dummy_pdev;
66
67void __init regulator_dummy_init(void)
68{
69	int ret;
70
71	dummy_pdev = platform_device_alloc("reg-dummy", -1);
72	if (!dummy_pdev) {
73		pr_err("Failed to allocate dummy regulator device\n");
74		return;
75	}
76
77	ret = platform_device_add(dummy_pdev);
78	if (ret != 0) {
79		pr_err("Failed to register dummy regulator device: %d\n", ret);
80		platform_device_put(dummy_pdev);
81		return;
82	}
83
84	ret = platform_driver_register(&dummy_regulator_driver);
85	if (ret != 0) {
86		pr_err("Failed to register dummy regulator driver: %d\n", ret);
87		platform_device_unregister(dummy_pdev);
88	}
89}
90