| 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | // |
| 3 | // Copyright (C) 2012 ARM Limited |
| 4 | |
| 5 | #define DRVNAME "vexpress-regulator" |
| 6 | #define pr_fmt(fmt) DRVNAME ": " fmt |
| 7 | |
| 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 | |
| 18 | static int vexpress_regulator_get_voltage(struct regulator_dev *regdev) |
| 19 | { |
| 20 | unsigned int uV; |
| 21 | int err = regmap_read(map: regdev->regmap, reg: 0, val: &uV); |
| 22 | |
| 23 | return err ? err : uV; |
| 24 | } |
| 25 | |
| 26 | static int vexpress_regulator_set_voltage(struct regulator_dev *regdev, |
| 27 | int min_uV, int max_uV, unsigned *selector) |
| 28 | { |
| 29 | return regmap_write(map: regdev->regmap, reg: 0, val: min_uV); |
| 30 | } |
| 31 | |
| 32 | static const struct regulator_ops vexpress_regulator_ops_ro = { |
| 33 | .get_voltage = vexpress_regulator_get_voltage, |
| 34 | }; |
| 35 | |
| 36 | static const struct regulator_ops vexpress_regulator_ops = { |
| 37 | .get_voltage = vexpress_regulator_get_voltage, |
| 38 | .set_voltage = vexpress_regulator_set_voltage, |
| 39 | }; |
| 40 | |
| 41 | static 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(dev: &pdev->dev, size: sizeof(*desc), GFP_KERNEL); |
| 50 | if (!desc) |
| 51 | return -ENOMEM; |
| 52 | |
| 53 | regmap = devm_regmap_init_vexpress_config(dev: &pdev->dev); |
| 54 | if (IS_ERR(ptr: regmap)) |
| 55 | return PTR_ERR(ptr: regmap); |
| 56 | |
| 57 | desc->name = dev_name(dev: &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(dev: &pdev->dev, node: 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 | else |
| 71 | 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(dev: &pdev->dev, regulator_desc: desc, config: &config); |
| 79 | return PTR_ERR_OR_ZERO(ptr: rdev); |
| 80 | } |
| 81 | |
| 82 | static const struct of_device_id vexpress_regulator_of_match[] = { |
| 83 | { .compatible = "arm,vexpress-volt" , }, |
| 84 | { } |
| 85 | }; |
| 86 | MODULE_DEVICE_TABLE(of, vexpress_regulator_of_match); |
| 87 | |
| 88 | static 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 | |
| 97 | module_platform_driver(vexpress_regulator_driver); |
| 98 | |
| 99 | MODULE_AUTHOR("Pawel Moll <pawel.moll@arm.com>" ); |
| 100 | MODULE_DESCRIPTION("Versatile Express regulator" ); |
| 101 | MODULE_LICENSE("GPL" ); |
| 102 | MODULE_ALIAS("platform:vexpress-regulator" ); |
| 103 | |