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 = 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 58 static struct platform_driver dummy_regulator_driver = { 59 .probe = dummy_regulator_probe, 60 .driver = { 61 .name = "reg-dummy", 62 }, 63 }; 64 65 static struct platform_device *dummy_pdev; 66 67 void __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