1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (c) 2015 MediaTek Inc.
4 // Author: Henry Chen <henryc.chen@mediatek.com>
5 
6 #include <linux/err.h>
7 #include <linux/i2c.h>
8 #include <linux/init.h>
9 #include <linux/interrupt.h>
10 #include <linux/module.h>
11 #include <linux/regmap.h>
12 #include <linux/regulator/driver.h>
13 #include <linux/regulator/machine.h>
14 #include <linux/regulator/of_regulator.h>
15 #include <linux/regulator/mt6311.h>
16 #include <linux/slab.h>
17 #include "mt6311-regulator.h"
18 
19 static const struct regmap_config mt6311_regmap_config = {
20 	.reg_bits = 8,
21 	.val_bits = 8,
22 	.max_register = MT6311_FQMTR_CON4,
23 	.cache_type = REGCACHE_MAPLE,
24 };
25 
26 /* Default limits measured in millivolts and milliamps */
27 #define MT6311_MIN_UV		600000
28 #define MT6311_MAX_UV		1393750
29 #define MT6311_STEP_UV		6250
30 
31 static const struct regulator_ops mt6311_buck_ops = {
32 	.list_voltage = regulator_list_voltage_linear,
33 	.map_voltage = regulator_map_voltage_linear,
34 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
35 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
36 	.set_voltage_time_sel = regulator_set_voltage_time_sel,
37 	.enable = regulator_enable_regmap,
38 	.disable = regulator_disable_regmap,
39 	.is_enabled = regulator_is_enabled_regmap,
40 };
41 
42 static const struct regulator_ops mt6311_ldo_ops = {
43 	.enable = regulator_enable_regmap,
44 	.disable = regulator_disable_regmap,
45 	.is_enabled = regulator_is_enabled_regmap,
46 };
47 
48 #define MT6311_BUCK(_id) \
49 {\
50 	.name = #_id,\
51 	.ops = &mt6311_buck_ops,\
52 	.of_match = of_match_ptr(#_id),\
53 	.regulators_node = of_match_ptr("regulators"),\
54 	.type = REGULATOR_VOLTAGE,\
55 	.id = MT6311_ID_##_id,\
56 	.n_voltages = (MT6311_MAX_UV - MT6311_MIN_UV) / MT6311_STEP_UV + 1,\
57 	.min_uV = MT6311_MIN_UV,\
58 	.uV_step = MT6311_STEP_UV,\
59 	.owner = THIS_MODULE,\
60 	.enable_reg = MT6311_VDVFS11_CON9,\
61 	.enable_mask = MT6311_PMIC_VDVFS11_EN_MASK,\
62 	.vsel_reg = MT6311_VDVFS11_CON12,\
63 	.vsel_mask = MT6311_PMIC_VDVFS11_VOSEL_MASK,\
64 }
65 
66 #define MT6311_LDO(_id) \
67 {\
68 	.name = #_id,\
69 	.ops = &mt6311_ldo_ops,\
70 	.of_match = of_match_ptr(#_id),\
71 	.regulators_node = of_match_ptr("regulators"),\
72 	.type = REGULATOR_VOLTAGE,\
73 	.id = MT6311_ID_##_id,\
74 	.owner = THIS_MODULE,\
75 	.enable_reg = MT6311_LDO_CON3,\
76 	.enable_mask = MT6311_PMIC_RG_VBIASN_EN_MASK,\
77 }
78 
79 static const struct regulator_desc mt6311_regulators[] = {
80 	MT6311_BUCK(VDVFS),
81 	MT6311_LDO(VBIASN),
82 };
83 
84 /*
85  * I2C driver interface functions
86  */
mt6311_i2c_probe(struct i2c_client * i2c)87 static int mt6311_i2c_probe(struct i2c_client *i2c)
88 {
89 	struct regulator_config config = { };
90 	struct regulator_dev *rdev;
91 	struct regmap *regmap;
92 	int i, ret;
93 	unsigned int data;
94 
95 	regmap = devm_regmap_init_i2c(i2c, &mt6311_regmap_config);
96 	if (IS_ERR(regmap)) {
97 		ret = PTR_ERR(regmap);
98 		dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
99 			ret);
100 		return ret;
101 	}
102 
103 	ret = regmap_read(regmap, MT6311_SWCID, &data);
104 	if (ret < 0) {
105 		dev_err(&i2c->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
106 		return ret;
107 	}
108 
109 	switch (data) {
110 	case MT6311_E1_CID_CODE:
111 	case MT6311_E2_CID_CODE:
112 	case MT6311_E3_CID_CODE:
113 		break;
114 	default:
115 		dev_err(&i2c->dev, "Unsupported device id = 0x%x.\n", data);
116 		return -ENODEV;
117 	}
118 
119 	for (i = 0; i < MT6311_MAX_REGULATORS; i++) {
120 		config.dev = &i2c->dev;
121 		config.regmap = regmap;
122 
123 		rdev = devm_regulator_register(&i2c->dev,
124 			&mt6311_regulators[i], &config);
125 		if (IS_ERR(rdev)) {
126 			dev_err(&i2c->dev,
127 				"Failed to register MT6311 regulator\n");
128 			return PTR_ERR(rdev);
129 		}
130 	}
131 
132 	return 0;
133 }
134 
135 static const struct i2c_device_id mt6311_i2c_id[] = {
136 	{ "mt6311" },
137 	{}
138 };
139 MODULE_DEVICE_TABLE(i2c, mt6311_i2c_id);
140 
141 #ifdef CONFIG_OF
142 static const struct of_device_id mt6311_dt_ids[] = {
143 	{ .compatible = "mediatek,mt6311-regulator",
144 	  .data = &mt6311_i2c_id[0] },
145 	{},
146 };
147 MODULE_DEVICE_TABLE(of, mt6311_dt_ids);
148 #endif
149 
150 static struct i2c_driver mt6311_regulator_driver = {
151 	.driver = {
152 		.name = "mt6311",
153 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
154 		.of_match_table = of_match_ptr(mt6311_dt_ids),
155 	},
156 	.probe = mt6311_i2c_probe,
157 	.id_table = mt6311_i2c_id,
158 };
159 
160 module_i2c_driver(mt6311_regulator_driver);
161 
162 MODULE_AUTHOR("Henry Chen <henryc.chen@mediatek.com>");
163 MODULE_DESCRIPTION("Regulator device driver for Mediatek MT6311");
164 MODULE_LICENSE("GPL v2");
165