1047ebaffSBjorn Andersson // SPDX-License-Identifier: GPL-2.0-only
2047ebaffSBjorn Andersson /*
3047ebaffSBjorn Andersson * Copyright (c) 2021, The Linux Foundation. All rights reserved.
4047ebaffSBjorn Andersson * Copyright (c) 2022, Linaro Ltd.
5047ebaffSBjorn Andersson */
6047ebaffSBjorn Andersson
7d5b4c8b9SMark Brown #include <linux/bitfield.h>
8047ebaffSBjorn Andersson #include <linux/gpio/consumer.h>
9047ebaffSBjorn Andersson #include <linux/i2c.h>
10047ebaffSBjorn Andersson #include <linux/module.h>
11047ebaffSBjorn Andersson #include <linux/of_platform.h>
12047ebaffSBjorn Andersson #include <linux/regmap.h>
13047ebaffSBjorn Andersson #include <linux/regulator/driver.h>
14047ebaffSBjorn Andersson #include <linux/regulator/machine.h>
15047ebaffSBjorn Andersson #include <linux/regulator/of_regulator.h>
16047ebaffSBjorn Andersson
17047ebaffSBjorn Andersson #define MAX20411_UV_STEP 6250
18047ebaffSBjorn Andersson #define MAX20411_BASE_UV 243750
19047ebaffSBjorn Andersson #define MAX20411_MIN_SEL 41 /* 0.5V */
20047ebaffSBjorn Andersson #define MAX20411_MAX_SEL 165 /* 1.275V */
21047ebaffSBjorn Andersson #define MAX20411_VID_OFFSET 0x7
22047ebaffSBjorn Andersson #define MAX20411_VID_MASK 0xff
23047ebaffSBjorn Andersson #define MAX20411_SLEW_OFFSET 0x6
24047ebaffSBjorn Andersson #define MAX20411_SLEW_DVS_MASK 0xc
25047ebaffSBjorn Andersson #define MAX20411_SLEW_SR_MASK 0x3
26047ebaffSBjorn Andersson
27047ebaffSBjorn Andersson struct max20411 {
28047ebaffSBjorn Andersson struct device *dev;
29047ebaffSBjorn Andersson struct device_node *of_node;
30047ebaffSBjorn Andersson struct regulator_desc desc;
31047ebaffSBjorn Andersson struct regulator_dev *rdev;
32047ebaffSBjorn Andersson struct regmap *regmap;
33047ebaffSBjorn Andersson };
34047ebaffSBjorn Andersson
35047ebaffSBjorn Andersson static const unsigned int max20411_slew_rates[] = { 13100, 6600, 3300, 1600 };
36047ebaffSBjorn Andersson
max20411_enable_time(struct regulator_dev * rdev)37047ebaffSBjorn Andersson static int max20411_enable_time(struct regulator_dev *rdev)
38047ebaffSBjorn Andersson {
39047ebaffSBjorn Andersson int voltage, rate, ret;
40047ebaffSBjorn Andersson unsigned int val;
41047ebaffSBjorn Andersson
42047ebaffSBjorn Andersson /* get voltage */
43047ebaffSBjorn Andersson ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val);
44047ebaffSBjorn Andersson if (ret)
45047ebaffSBjorn Andersson return ret;
46047ebaffSBjorn Andersson
47047ebaffSBjorn Andersson val &= rdev->desc->vsel_mask;
48047ebaffSBjorn Andersson voltage = regulator_list_voltage_linear(rdev, val);
49047ebaffSBjorn Andersson
50047ebaffSBjorn Andersson /* get rate */
51047ebaffSBjorn Andersson ret = regmap_read(rdev->regmap, MAX20411_SLEW_OFFSET, &val);
52047ebaffSBjorn Andersson if (ret)
53047ebaffSBjorn Andersson return ret;
54047ebaffSBjorn Andersson
55047ebaffSBjorn Andersson val = FIELD_GET(MAX20411_SLEW_SR_MASK, val);
56047ebaffSBjorn Andersson rate = max20411_slew_rates[val];
57047ebaffSBjorn Andersson
58047ebaffSBjorn Andersson return DIV_ROUND_UP(voltage, rate);
59047ebaffSBjorn Andersson }
60047ebaffSBjorn Andersson
61047ebaffSBjorn Andersson static const struct regmap_config max20411_regmap_config = {
62047ebaffSBjorn Andersson .reg_bits = 8,
63047ebaffSBjorn Andersson .val_bits = 8,
64047ebaffSBjorn Andersson .max_register = 0xe,
65047ebaffSBjorn Andersson };
66047ebaffSBjorn Andersson
67047ebaffSBjorn Andersson static const struct regulator_ops max20411_ops = {
68047ebaffSBjorn Andersson .get_voltage_sel = regulator_get_voltage_sel_regmap,
69047ebaffSBjorn Andersson .set_voltage_sel = regulator_set_voltage_sel_regmap,
70047ebaffSBjorn Andersson .list_voltage = regulator_list_voltage_linear,
71047ebaffSBjorn Andersson .enable_time = max20411_enable_time,
72047ebaffSBjorn Andersson };
73047ebaffSBjorn Andersson
74047ebaffSBjorn Andersson static const struct regulator_desc max20411_desc = {
75047ebaffSBjorn Andersson .ops = &max20411_ops,
76047ebaffSBjorn Andersson .owner = THIS_MODULE,
77047ebaffSBjorn Andersson .type = REGULATOR_VOLTAGE,
78047ebaffSBjorn Andersson .supply_name = "vin",
79047ebaffSBjorn Andersson .name = "max20411",
80047ebaffSBjorn Andersson
81047ebaffSBjorn Andersson /*
82047ebaffSBjorn Andersson * voltage = 0.24375V + selector * 6.25mV
83047ebaffSBjorn Andersson * with valid selector between 41 to 165 (0.5V to 1.275V)
84047ebaffSBjorn Andersson */
85047ebaffSBjorn Andersson .min_uV = MAX20411_BASE_UV,
86047ebaffSBjorn Andersson .uV_step = MAX20411_UV_STEP,
87047ebaffSBjorn Andersson .linear_min_sel = MAX20411_MIN_SEL,
889d1c7319SAxel Lin .n_voltages = MAX20411_MAX_SEL + 1,
89047ebaffSBjorn Andersson
90047ebaffSBjorn Andersson .vsel_reg = MAX20411_VID_OFFSET,
91047ebaffSBjorn Andersson .vsel_mask = MAX20411_VID_MASK,
92047ebaffSBjorn Andersson
93047ebaffSBjorn Andersson .ramp_reg = MAX20411_SLEW_OFFSET,
94047ebaffSBjorn Andersson .ramp_mask = MAX20411_SLEW_DVS_MASK,
95047ebaffSBjorn Andersson .ramp_delay_table = max20411_slew_rates,
96047ebaffSBjorn Andersson .n_ramp_values = ARRAY_SIZE(max20411_slew_rates),
97047ebaffSBjorn Andersson };
98047ebaffSBjorn Andersson
max20411_probe(struct i2c_client * client)99fad8dddaSUwe Kleine-König static int max20411_probe(struct i2c_client *client)
100047ebaffSBjorn Andersson {
101047ebaffSBjorn Andersson struct regulator_init_data *init_data;
102047ebaffSBjorn Andersson struct device *dev = &client->dev;
103047ebaffSBjorn Andersson struct regulator_config cfg = {};
104047ebaffSBjorn Andersson struct max20411 *max20411;
105047ebaffSBjorn Andersson
106047ebaffSBjorn Andersson max20411 = devm_kzalloc(dev, sizeof(*max20411), GFP_KERNEL);
107047ebaffSBjorn Andersson if (!max20411)
108047ebaffSBjorn Andersson return -ENOMEM;
109047ebaffSBjorn Andersson
110047ebaffSBjorn Andersson max20411->regmap = devm_regmap_init_i2c(client, &max20411_regmap_config);
111047ebaffSBjorn Andersson if (IS_ERR(max20411->regmap)) {
112047ebaffSBjorn Andersson dev_err(dev, "Failed to allocate regmap!\n");
113047ebaffSBjorn Andersson return PTR_ERR(max20411->regmap);
114047ebaffSBjorn Andersson }
115047ebaffSBjorn Andersson
116047ebaffSBjorn Andersson max20411->dev = dev;
117047ebaffSBjorn Andersson max20411->of_node = dev->of_node;
118047ebaffSBjorn Andersson
119047ebaffSBjorn Andersson max20411->desc = max20411_desc;
120047ebaffSBjorn Andersson init_data = of_get_regulator_init_data(max20411->dev, max20411->of_node, &max20411->desc);
121047ebaffSBjorn Andersson if (!init_data)
122047ebaffSBjorn Andersson return -ENODATA;
123047ebaffSBjorn Andersson
124047ebaffSBjorn Andersson cfg.dev = max20411->dev;
125047ebaffSBjorn Andersson cfg.init_data = init_data;
126047ebaffSBjorn Andersson cfg.of_node = max20411->of_node;
127047ebaffSBjorn Andersson cfg.driver_data = max20411;
128047ebaffSBjorn Andersson
129047ebaffSBjorn Andersson cfg.ena_gpiod = gpiod_get(max20411->dev, "enable", GPIOD_ASIS);
130047ebaffSBjorn Andersson if (IS_ERR(cfg.ena_gpiod))
131047ebaffSBjorn Andersson return dev_err_probe(dev, PTR_ERR(cfg.ena_gpiod),
132047ebaffSBjorn Andersson "unable to acquire enable gpio\n");
133047ebaffSBjorn Andersson
134047ebaffSBjorn Andersson max20411->rdev = devm_regulator_register(max20411->dev, &max20411->desc, &cfg);
135047ebaffSBjorn Andersson if (IS_ERR(max20411->rdev))
136047ebaffSBjorn Andersson dev_err(max20411->dev, "Failed to register regulator\n");
137047ebaffSBjorn Andersson
138047ebaffSBjorn Andersson return PTR_ERR_OR_ZERO(max20411->rdev);
139047ebaffSBjorn Andersson }
140047ebaffSBjorn Andersson
141047ebaffSBjorn Andersson static const struct of_device_id of_max20411_match_tbl[] = {
142047ebaffSBjorn Andersson { .compatible = "maxim,max20411", },
143047ebaffSBjorn Andersson { },
144047ebaffSBjorn Andersson };
145047ebaffSBjorn Andersson MODULE_DEVICE_TABLE(of, of_max20411_match_tbl);
146047ebaffSBjorn Andersson
147047ebaffSBjorn Andersson static const struct i2c_device_id max20411_id[] = {
148047ebaffSBjorn Andersson { "max20411", 0 },
149047ebaffSBjorn Andersson { },
150047ebaffSBjorn Andersson };
151047ebaffSBjorn Andersson MODULE_DEVICE_TABLE(i2c, max20411_id);
152047ebaffSBjorn Andersson
153047ebaffSBjorn Andersson static struct i2c_driver max20411_i2c_driver = {
154047ebaffSBjorn Andersson .driver = {
155047ebaffSBjorn Andersson .name = "max20411",
156bdce47bbSDouglas Anderson .probe_type = PROBE_PREFER_ASYNCHRONOUS,
157047ebaffSBjorn Andersson .of_match_table = of_max20411_match_tbl,
158047ebaffSBjorn Andersson },
159*964e1865SUwe Kleine-König .probe = max20411_probe,
160047ebaffSBjorn Andersson .id_table = max20411_id,
161047ebaffSBjorn Andersson };
162047ebaffSBjorn Andersson module_i2c_driver(max20411_i2c_driver);
163047ebaffSBjorn Andersson
164047ebaffSBjorn Andersson MODULE_LICENSE("GPL");
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