1/*
2 * max77843.c - Regulator driver for the Maxim MAX77843
3 *
4 * Copyright (C) 2015 Samsung Electronics
5 * Author: Jaewon Kim <jaewon02.kim@samsung.com>
6 * Author: Beomho Seo <beomho.seo@samsung.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 */
13
14#include <linux/module.h>
15#include <linux/platform_device.h>
16#include <linux/regulator/driver.h>
17#include <linux/regulator/machine.h>
18#include <linux/mfd/max77843-private.h>
19#include <linux/regulator/of_regulator.h>
20
21enum max77843_regulator_type {
22	MAX77843_SAFEOUT1 = 0,
23	MAX77843_SAFEOUT2,
24	MAX77843_CHARGER,
25
26	MAX77843_NUM,
27};
28
29static const unsigned int max77843_safeout_voltage_table[] = {
30	4850000,
31	4900000,
32	4950000,
33	3300000,
34};
35
36static int max77843_reg_is_enabled(struct regulator_dev *rdev)
37{
38	struct regmap *regmap = rdev->regmap;
39	int ret;
40	unsigned int reg;
41
42	ret = regmap_read(regmap, rdev->desc->enable_reg, &reg);
43	if (ret) {
44		dev_err(&rdev->dev, "Fialed to read charger register\n");
45		return ret;
46	}
47
48	return (reg & rdev->desc->enable_mask) == rdev->desc->enable_mask;
49}
50
51static int max77843_reg_get_current_limit(struct regulator_dev *rdev)
52{
53	struct regmap *regmap = rdev->regmap;
54	unsigned int chg_min_uA = rdev->constraints->min_uA;
55	unsigned int chg_max_uA = rdev->constraints->max_uA;
56	unsigned int val;
57	int ret;
58	unsigned int reg, sel;
59
60	ret = regmap_read(regmap, MAX77843_CHG_REG_CHG_CNFG_02, &reg);
61	if (ret) {
62		dev_err(&rdev->dev, "Failed to read charger register\n");
63		return ret;
64	}
65
66	sel = reg & MAX77843_CHG_FAST_CHG_CURRENT_MASK;
67
68	if (sel < 0x03)
69		sel = 0;
70	else
71		sel -= 2;
72
73	val = chg_min_uA + MAX77843_CHG_FAST_CHG_CURRENT_STEP * sel;
74	if (val > chg_max_uA)
75		return -EINVAL;
76
77	return val;
78}
79
80static int max77843_reg_set_current_limit(struct regulator_dev *rdev,
81		int min_uA, int max_uA)
82{
83	struct regmap *regmap = rdev->regmap;
84	unsigned int chg_min_uA = rdev->constraints->min_uA;
85	int sel = 0;
86
87	while (chg_min_uA + MAX77843_CHG_FAST_CHG_CURRENT_STEP * sel < min_uA)
88		sel++;
89
90	if (chg_min_uA + MAX77843_CHG_FAST_CHG_CURRENT_STEP * sel > max_uA)
91		return -EINVAL;
92
93	sel += 2;
94
95	return regmap_write(regmap, MAX77843_CHG_REG_CHG_CNFG_02, sel);
96}
97
98static struct regulator_ops max77843_charger_ops = {
99	.is_enabled		= max77843_reg_is_enabled,
100	.enable			= regulator_enable_regmap,
101	.disable		= regulator_disable_regmap,
102	.get_current_limit	= max77843_reg_get_current_limit,
103	.set_current_limit	= max77843_reg_set_current_limit,
104};
105
106static struct regulator_ops max77843_regulator_ops = {
107	.is_enabled             = regulator_is_enabled_regmap,
108	.enable                 = regulator_enable_regmap,
109	.disable                = regulator_disable_regmap,
110	.list_voltage		= regulator_list_voltage_table,
111	.get_voltage_sel        = regulator_get_voltage_sel_regmap,
112	.set_voltage_sel        = regulator_set_voltage_sel_regmap,
113};
114
115static const struct regulator_desc max77843_supported_regulators[] = {
116	[MAX77843_SAFEOUT1] = {
117		.name		= "SAFEOUT1",
118		.id		= MAX77843_SAFEOUT1,
119		.ops		= &max77843_regulator_ops,
120		.of_match	= of_match_ptr("SAFEOUT1"),
121		.regulators_node = of_match_ptr("regulators"),
122		.type		= REGULATOR_VOLTAGE,
123		.owner		= THIS_MODULE,
124		.n_voltages	= ARRAY_SIZE(max77843_safeout_voltage_table),
125		.volt_table	= max77843_safeout_voltage_table,
126		.enable_reg	= MAX77843_SYS_REG_SAFEOUTCTRL,
127		.enable_mask	= MAX77843_REG_SAFEOUTCTRL_ENSAFEOUT1,
128		.vsel_reg	= MAX77843_SYS_REG_SAFEOUTCTRL,
129		.vsel_mask	= MAX77843_REG_SAFEOUTCTRL_SAFEOUT1_MASK,
130	},
131	[MAX77843_SAFEOUT2] = {
132		.name           = "SAFEOUT2",
133		.id             = MAX77843_SAFEOUT2,
134		.ops            = &max77843_regulator_ops,
135		.of_match	= of_match_ptr("SAFEOUT2"),
136		.regulators_node = of_match_ptr("regulators"),
137		.type           = REGULATOR_VOLTAGE,
138		.owner          = THIS_MODULE,
139		.n_voltages	= ARRAY_SIZE(max77843_safeout_voltage_table),
140		.volt_table	= max77843_safeout_voltage_table,
141		.enable_reg     = MAX77843_SYS_REG_SAFEOUTCTRL,
142		.enable_mask    = MAX77843_REG_SAFEOUTCTRL_ENSAFEOUT2,
143		.vsel_reg	= MAX77843_SYS_REG_SAFEOUTCTRL,
144		.vsel_mask	= MAX77843_REG_SAFEOUTCTRL_SAFEOUT2_MASK,
145	},
146	[MAX77843_CHARGER] = {
147		.name		= "CHARGER",
148		.id		= MAX77843_CHARGER,
149		.ops		= &max77843_charger_ops,
150		.of_match	= of_match_ptr("CHARGER"),
151		.regulators_node = of_match_ptr("regulators"),
152		.type		= REGULATOR_CURRENT,
153		.owner		= THIS_MODULE,
154		.enable_reg	= MAX77843_CHG_REG_CHG_CNFG_00,
155		.enable_mask	= MAX77843_CHG_MASK,
156	},
157};
158
159static struct regmap *max77843_get_regmap(struct max77843 *max77843, int reg_id)
160{
161	switch (reg_id) {
162	case MAX77843_SAFEOUT1:
163	case MAX77843_SAFEOUT2:
164		return max77843->regmap;
165	case MAX77843_CHARGER:
166		return max77843->regmap_chg;
167	default:
168		return max77843->regmap;
169	}
170}
171
172static int max77843_regulator_probe(struct platform_device *pdev)
173{
174	struct max77843 *max77843 = dev_get_drvdata(pdev->dev.parent);
175	struct regulator_config config = {};
176	int i;
177
178	config.dev = max77843->dev;
179	config.driver_data = max77843;
180
181	for (i = 0; i < ARRAY_SIZE(max77843_supported_regulators); i++) {
182		struct regulator_dev *regulator;
183
184		config.regmap = max77843_get_regmap(max77843,
185				max77843_supported_regulators[i].id);
186
187		regulator = devm_regulator_register(&pdev->dev,
188				&max77843_supported_regulators[i], &config);
189		if (IS_ERR(regulator)) {
190			dev_err(&pdev->dev,
191					"Failed to regiser regulator-%d\n", i);
192			return PTR_ERR(regulator);
193		}
194	}
195
196	return 0;
197}
198
199static const struct platform_device_id max77843_regulator_id[] = {
200	{ "max77843-regulator", },
201	{ /* sentinel */ },
202};
203
204static struct platform_driver max77843_regulator_driver = {
205	.driver	= {
206		.name = "max77843-regulator",
207	},
208	.probe		= max77843_regulator_probe,
209	.id_table	= max77843_regulator_id,
210};
211
212static int __init max77843_regulator_init(void)
213{
214	return platform_driver_register(&max77843_regulator_driver);
215}
216subsys_initcall(max77843_regulator_init);
217
218static void __exit max77843_regulator_exit(void)
219{
220	platform_driver_unregister(&max77843_regulator_driver);
221}
222module_exit(max77843_regulator_exit);
223
224MODULE_AUTHOR("Jaewon Kim <jaewon02.kim@samsung.com>");
225MODULE_AUTHOR("Beomho Seo <beomho.seo@samsung.com>");
226MODULE_DESCRIPTION("Maxim MAX77843 regulator driver");
227MODULE_LICENSE("GPL");
228