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 22 struct regulator_dev *dummy_regulator_rdev; 23 24 static const struct regulator_init_data dummy_initdata = { 25 .constraints = { 26 .always_on = 1, 27 }, 28 }; 29 30 static const struct regulator_ops dummy_ops; 31 32 static 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 40 static 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(&pdev->dev, &dummy_desc, 49 &config); 50 if (IS_ERR(dummy_regulator_rdev)) { 51 ret = PTR_ERR(dummy_regulator_rdev); 52 pr_err("Failed to register regulator: %d\n", ret); 53 return ret; 54 } 55 56 return 0; 57 } 58 59 static 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 67 static struct platform_device *dummy_pdev; 68 69 void __init regulator_dummy_init(void) 70 { 71 int ret; 72 73 dummy_pdev = platform_device_alloc("reg-dummy", -1); 74 if (!dummy_pdev) { 75 pr_err("Failed to allocate dummy regulator device\n"); 76 return; 77 } 78 79 ret = platform_device_add(dummy_pdev); 80 if (ret != 0) { 81 pr_err("Failed to register dummy regulator device: %d\n", ret); 82 platform_device_put(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