1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Regulator driver for STw4810/STw4811 VMMC regulator.
4 *
5 * Copyright (C) 2013 ST-Ericsson SA
6 * Written on behalf of Linaro for ST-Ericsson
7 *
8 * Author: Linus Walleij <linus.walleij@linaro.org>
9 */
10
11#include <linux/err.h>
12#include <linux/init.h>
13#include <linux/mfd/stw481x.h>
14#include <linux/module.h>
15#include <linux/platform_device.h>
16#include <linux/regulator/driver.h>
17#include <linux/regulator/of_regulator.h>
18
19static const unsigned int stw481x_vmmc_voltages[] = {
20	1800000,
21	1800000,
22	2850000,
23	3000000,
24	1850000,
25	2600000,
26	2700000,
27	3300000,
28};
29
30static const struct regulator_ops stw481x_vmmc_ops = {
31	.list_voltage = regulator_list_voltage_table,
32	.enable      = regulator_enable_regmap,
33	.disable     = regulator_disable_regmap,
34	.is_enabled  = regulator_is_enabled_regmap,
35	.get_voltage_sel = regulator_get_voltage_sel_regmap,
36	.set_voltage_sel = regulator_set_voltage_sel_regmap,
37};
38
39static const struct regulator_desc vmmc_regulator = {
40	.name = "VMMC",
41	.id   = 0,
42	.ops  = &stw481x_vmmc_ops,
43	.type = REGULATOR_VOLTAGE,
44	.owner = THIS_MODULE,
45	.n_voltages = ARRAY_SIZE(stw481x_vmmc_voltages),
46	.volt_table = stw481x_vmmc_voltages,
47	.enable_time = 200, /* FIXME: look this up */
48	.enable_reg = STW_CONF1,
49	.enable_mask = STW_CONF1_PDN_VMMC | STW_CONF1_MMC_LS_STATUS,
50	.enable_val = STW_CONF1_PDN_VMMC,
51	.vsel_reg = STW_CONF1,
52	.vsel_mask = STW_CONF1_VMMC_MASK,
53};
54
55static int stw481x_vmmc_regulator_probe(struct platform_device *pdev)
56{
57	struct stw481x *stw481x = dev_get_platdata(&pdev->dev);
58	struct regulator_config config = { };
59	struct regulator_dev *rdev;
60	int ret;
61
62	/* First disable the external VMMC if it's active */
63	ret = regmap_update_bits(stw481x->map, STW_CONF2,
64				 STW_CONF2_VMMC_EXT, 0);
65	if (ret) {
66		dev_err(&pdev->dev, "could not disable external VMMC\n");
67		return ret;
68	}
69
70	/* Register VMMC regulator */
71	config.dev = &pdev->dev;
72	config.driver_data = stw481x;
73	config.regmap = stw481x->map;
74	config.of_node = pdev->dev.of_node;
75	config.init_data = of_get_regulator_init_data(&pdev->dev,
76						      pdev->dev.of_node,
77						      &vmmc_regulator);
78
79	rdev = devm_regulator_register(&pdev->dev, &vmmc_regulator, &config);
80	if (IS_ERR(rdev)) {
81		dev_err(&pdev->dev,
82			"error initializing STw481x VMMC regulator\n");
83		return PTR_ERR(rdev);
84	}
85
86	dev_info(&pdev->dev, "initialized STw481x VMMC regulator\n");
87	return 0;
88}
89
90static const struct of_device_id stw481x_vmmc_match[] = {
91	{ .compatible = "st,stw481x-vmmc", },
92	{},
93};
94
95static struct platform_driver stw481x_vmmc_regulator_driver = {
96	.driver = {
97		.name  = "stw481x-vmmc-regulator",
98		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
99		.of_match_table = stw481x_vmmc_match,
100	},
101	.probe = stw481x_vmmc_regulator_probe,
102};
103
104module_platform_driver(stw481x_vmmc_regulator_driver);
105