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1// SPDX-License-Identifier: GPL-2.02//3// Copyright (C) 2012 ARM Limited4 5#define DRVNAME "vexpress-regulator"6#define pr_fmt(fmt) DRVNAME ": " fmt7 8#include <linux/device.h>9#include <linux/err.h>10#include <linux/module.h>11#include <linux/mod_devicetable.h>12#include <linux/platform_device.h>13#include <linux/regulator/driver.h>14#include <linux/regulator/machine.h>15#include <linux/regulator/of_regulator.h>16#include <linux/vexpress.h>17 18static int vexpress_regulator_get_voltage(struct regulator_dev *regdev)19{20 unsigned int uV;21 int err = regmap_read(regdev->regmap, 0, &uV);22 23 return err ? err : uV;24}25 26static int vexpress_regulator_set_voltage(struct regulator_dev *regdev,27 int min_uV, int max_uV, unsigned *selector)28{29 return regmap_write(regdev->regmap, 0, min_uV);30}31 32static const struct regulator_ops vexpress_regulator_ops_ro = {33 .get_voltage = vexpress_regulator_get_voltage,34};35 36static const struct regulator_ops vexpress_regulator_ops = {37 .get_voltage = vexpress_regulator_get_voltage,38 .set_voltage = vexpress_regulator_set_voltage,39};40 41static int vexpress_regulator_probe(struct platform_device *pdev)42{43 struct regulator_desc *desc;44 struct regulator_init_data *init_data;45 struct regulator_config config = { };46 struct regulator_dev *rdev;47 struct regmap *regmap;48 49 desc = devm_kzalloc(&pdev->dev, sizeof(*desc), GFP_KERNEL);50 if (!desc)51 return -ENOMEM;52 53 regmap = devm_regmap_init_vexpress_config(&pdev->dev);54 if (IS_ERR(regmap))55 return PTR_ERR(regmap);56 57 desc->name = dev_name(&pdev->dev);58 desc->type = REGULATOR_VOLTAGE;59 desc->owner = THIS_MODULE;60 desc->continuous_voltage_range = true;61 62 init_data = of_get_regulator_init_data(&pdev->dev, pdev->dev.of_node,63 desc);64 if (!init_data)65 return -EINVAL;66 67 init_data->constraints.apply_uV = 0;68 if (init_data->constraints.min_uV && init_data->constraints.max_uV)69 desc->ops = &vexpress_regulator_ops;70 else71 desc->ops = &vexpress_regulator_ops_ro;72 73 config.regmap = regmap;74 config.dev = &pdev->dev;75 config.init_data = init_data;76 config.of_node = pdev->dev.of_node;77 78 rdev = devm_regulator_register(&pdev->dev, desc, &config);79 return PTR_ERR_OR_ZERO(rdev);80}81 82static const struct of_device_id vexpress_regulator_of_match[] = {83 { .compatible = "arm,vexpress-volt", },84 { }85};86MODULE_DEVICE_TABLE(of, vexpress_regulator_of_match);87 88static struct platform_driver vexpress_regulator_driver = {89 .probe = vexpress_regulator_probe,90 .driver = {91 .name = DRVNAME,92 .probe_type = PROBE_PREFER_ASYNCHRONOUS,93 .of_match_table = vexpress_regulator_of_match,94 },95};96 97module_platform_driver(vexpress_regulator_driver);98 99MODULE_AUTHOR("Pawel Moll <pawel.moll@arm.com>");100MODULE_DESCRIPTION("Versatile Express regulator");101MODULE_LICENSE("GPL");102MODULE_ALIAS("platform:vexpress-regulator");103