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 = devm_regulator_register(dev: &pdev->dev, regulator_desc: &dummy_desc,
49 config: &config);
50 if (IS_ERR(ptr: dummy_regulator_rdev)) {
51 ret = PTR_ERR(ptr: dummy_regulator_rdev);
52 pr_err("Failed to register regulator: %d\n", ret);
53 return ret;
54 }
55
56 return 0;
57}
58
59static struct platform_driver dummy_regulator_driver = {
60 .probe = dummy_regulator_probe,
61 .driver = {
62 .name = "reg-dummy",
63 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
64 },
65};
66
67static struct platform_device *dummy_pdev;
68
69void __init regulator_dummy_init(void)
70{
71 int ret;
72
73 dummy_pdev = platform_device_alloc(name: "reg-dummy", id: -1);
74 if (!dummy_pdev) {
75 pr_err("Failed to allocate dummy regulator device\n");
76 return;
77 }
78
79 ret = platform_device_add(pdev: dummy_pdev);
80 if (ret != 0) {
81 pr_err("Failed to register dummy regulator device: %d\n", ret);
82 platform_device_put(pdev: dummy_pdev);
83 return;
84 }
85
86 ret = platform_driver_register(&dummy_regulator_driver);
87 if (ret != 0) {
88 pr_err("Failed to register dummy regulator driver: %d\n", ret);
89 platform_device_unregister(dummy_pdev);
90 }
91}
92

source code of linux/drivers/regulator/dummy.c