1 /*
2  * Copyright (c) 2015 MediaTek Inc.
3  * Author: Henry Chen <henryc.chen@mediatek.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  */
14 
15 #include <linux/err.h>
16 #include <linux/gpio.h>
17 #include <linux/i2c.h>
18 #include <linux/init.h>
19 #include <linux/interrupt.h>
20 #include <linux/module.h>
21 #include <linux/regmap.h>
22 #include <linux/regulator/driver.h>
23 #include <linux/regulator/machine.h>
24 #include <linux/regulator/of_regulator.h>
25 #include <linux/regulator/mt6311.h>
26 #include <linux/slab.h>
27 #include "mt6311-regulator.h"
28 
29 static const struct regmap_config mt6311_regmap_config = {
30 	.reg_bits = 8,
31 	.val_bits = 8,
32 	.max_register = MT6311_FQMTR_CON4,
33 	.cache_type = REGCACHE_RBTREE,
34 };
35 
36 /* Default limits measured in millivolts and milliamps */
37 #define MT6311_MIN_UV		600000
38 #define MT6311_MAX_UV		1393750
39 #define MT6311_STEP_UV		6250
40 
41 static const struct regulator_linear_range buck_volt_range[] = {
42 	REGULATOR_LINEAR_RANGE(MT6311_MIN_UV, 0, 0x7f, MT6311_STEP_UV),
43 };
44 
45 static const struct regulator_ops mt6311_buck_ops = {
46 	.list_voltage = regulator_list_voltage_linear_range,
47 	.map_voltage = regulator_map_voltage_linear_range,
48 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
49 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
50 	.set_voltage_time_sel = regulator_set_voltage_time_sel,
51 	.enable = regulator_enable_regmap,
52 	.disable = regulator_disable_regmap,
53 	.is_enabled = regulator_is_enabled_regmap,
54 };
55 
56 static const struct regulator_ops mt6311_ldo_ops = {
57 	.enable = regulator_enable_regmap,
58 	.disable = regulator_disable_regmap,
59 	.is_enabled = regulator_is_enabled_regmap,
60 };
61 
62 #define MT6311_BUCK(_id) \
63 {\
64 	.name = #_id,\
65 	.ops = &mt6311_buck_ops,\
66 	.of_match = of_match_ptr(#_id),\
67 	.regulators_node = of_match_ptr("regulators"),\
68 	.type = REGULATOR_VOLTAGE,\
69 	.id = MT6311_ID_##_id,\
70 	.n_voltages = (MT6311_MAX_UV - MT6311_MIN_UV) / MT6311_STEP_UV + 1,\
71 	.min_uV = MT6311_MIN_UV,\
72 	.uV_step = MT6311_STEP_UV,\
73 	.owner = THIS_MODULE,\
74 	.linear_ranges = buck_volt_range, \
75 	.n_linear_ranges = ARRAY_SIZE(buck_volt_range), \
76 	.enable_reg = MT6311_VDVFS11_CON9,\
77 	.enable_mask = MT6311_PMIC_VDVFS11_EN_MASK,\
78 	.vsel_reg = MT6311_VDVFS11_CON12,\
79 	.vsel_mask = MT6311_PMIC_VDVFS11_VOSEL_MASK,\
80 }
81 
82 #define MT6311_LDO(_id) \
83 {\
84 	.name = #_id,\
85 	.ops = &mt6311_ldo_ops,\
86 	.of_match = of_match_ptr(#_id),\
87 	.regulators_node = of_match_ptr("regulators"),\
88 	.type = REGULATOR_VOLTAGE,\
89 	.id = MT6311_ID_##_id,\
90 	.owner = THIS_MODULE,\
91 	.enable_reg = MT6311_LDO_CON3,\
92 	.enable_mask = MT6311_PMIC_RG_VBIASN_EN_MASK,\
93 }
94 
95 static const struct regulator_desc mt6311_regulators[] = {
96 	MT6311_BUCK(VDVFS),
97 	MT6311_LDO(VBIASN),
98 };
99 
100 /*
101  * I2C driver interface functions
102  */
103 static int mt6311_i2c_probe(struct i2c_client *i2c,
104 		const struct i2c_device_id *id)
105 {
106 	struct regulator_config config = { };
107 	struct regulator_dev *rdev;
108 	struct regmap *regmap;
109 	int i, ret;
110 	unsigned int data;
111 
112 	regmap = devm_regmap_init_i2c(i2c, &mt6311_regmap_config);
113 	if (IS_ERR(regmap)) {
114 		ret = PTR_ERR(regmap);
115 		dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
116 			ret);
117 		return ret;
118 	}
119 
120 	ret = regmap_read(regmap, MT6311_SWCID, &data);
121 	if (ret < 0) {
122 		dev_err(&i2c->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
123 		return ret;
124 	}
125 
126 	switch (data) {
127 	case MT6311_E1_CID_CODE:
128 	case MT6311_E2_CID_CODE:
129 	case MT6311_E3_CID_CODE:
130 		break;
131 	default:
132 		dev_err(&i2c->dev, "Unsupported device id = 0x%x.\n", data);
133 		return -ENODEV;
134 	}
135 
136 	for (i = 0; i < MT6311_MAX_REGULATORS; i++) {
137 		config.dev = &i2c->dev;
138 		config.regmap = regmap;
139 
140 		rdev = devm_regulator_register(&i2c->dev,
141 			&mt6311_regulators[i], &config);
142 		if (IS_ERR(rdev)) {
143 			dev_err(&i2c->dev,
144 				"Failed to register MT6311 regulator\n");
145 			return PTR_ERR(rdev);
146 		}
147 	}
148 
149 	return 0;
150 }
151 
152 static const struct i2c_device_id mt6311_i2c_id[] = {
153 	{"mt6311", 0},
154 	{},
155 };
156 MODULE_DEVICE_TABLE(i2c, mt6311_i2c_id);
157 
158 #ifdef CONFIG_OF
159 static const struct of_device_id mt6311_dt_ids[] = {
160 	{ .compatible = "mediatek,mt6311-regulator",
161 	  .data = &mt6311_i2c_id[0] },
162 	{},
163 };
164 MODULE_DEVICE_TABLE(of, mt6311_dt_ids);
165 #endif
166 
167 static struct i2c_driver mt6311_regulator_driver = {
168 	.driver = {
169 		.name = "mt6311",
170 		.of_match_table = of_match_ptr(mt6311_dt_ids),
171 	},
172 	.probe = mt6311_i2c_probe,
173 	.id_table = mt6311_i2c_id,
174 };
175 
176 module_i2c_driver(mt6311_regulator_driver);
177 
178 MODULE_AUTHOR("Henry Chen <henryc.chen@mediatek.com>");
179 MODULE_DESCRIPTION("Regulator device driver for Mediatek MT6311");
180 MODULE_LICENSE("GPL v2");
181