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 | |