xref: /linux/drivers/regulator/dummy.c (revision fcc8487d477a3452a1d0ccbdd4c5e0e1e3cb8bed)
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 }
94