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_ops mt6311_buck_ops = {
42 	.list_voltage = regulator_list_voltage_linear,
43 	.map_voltage = regulator_map_voltage_linear,
44 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
45 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
46 	.set_voltage_time_sel = regulator_set_voltage_time_sel,
47 	.enable = regulator_enable_regmap,
48 	.disable = regulator_disable_regmap,
49 	.is_enabled = regulator_is_enabled_regmap,
50 };
51 
52 static const struct regulator_ops mt6311_ldo_ops = {
53 	.enable = regulator_enable_regmap,
54 	.disable = regulator_disable_regmap,
55 	.is_enabled = regulator_is_enabled_regmap,
56 };
57 
58 #define MT6311_BUCK(_id) \
59 {\
60 	.name = #_id,\
61 	.ops = &mt6311_buck_ops,\
62 	.of_match = of_match_ptr(#_id),\
63 	.regulators_node = of_match_ptr("regulators"),\
64 	.type = REGULATOR_VOLTAGE,\
65 	.id = MT6311_ID_##_id,\
66 	.n_voltages = (MT6311_MAX_UV - MT6311_MIN_UV) / MT6311_STEP_UV + 1,\
67 	.min_uV = MT6311_MIN_UV,\
68 	.uV_step = MT6311_STEP_UV,\
69 	.owner = THIS_MODULE,\
70 	.enable_reg = MT6311_VDVFS11_CON9,\
71 	.enable_mask = MT6311_PMIC_VDVFS11_EN_MASK,\
72 	.vsel_reg = MT6311_VDVFS11_CON12,\
73 	.vsel_mask = MT6311_PMIC_VDVFS11_VOSEL_MASK,\
74 }
75 
76 #define MT6311_LDO(_id) \
77 {\
78 	.name = #_id,\
79 	.ops = &mt6311_ldo_ops,\
80 	.of_match = of_match_ptr(#_id),\
81 	.regulators_node = of_match_ptr("regulators"),\
82 	.type = REGULATOR_VOLTAGE,\
83 	.id = MT6311_ID_##_id,\
84 	.owner = THIS_MODULE,\
85 	.enable_reg = MT6311_LDO_CON3,\
86 	.enable_mask = MT6311_PMIC_RG_VBIASN_EN_MASK,\
87 }
88 
89 static const struct regulator_desc mt6311_regulators[] = {
90 	MT6311_BUCK(VDVFS),
91 	MT6311_LDO(VBIASN),
92 };
93 
94 /*
95  * I2C driver interface functions
96  */
97 static int mt6311_i2c_probe(struct i2c_client *i2c,
98 		const struct i2c_device_id *id)
99 {
100 	struct regulator_config config = { };
101 	struct regulator_dev *rdev;
102 	struct regmap *regmap;
103 	int i, ret;
104 	unsigned int data;
105 
106 	regmap = devm_regmap_init_i2c(i2c, &mt6311_regmap_config);
107 	if (IS_ERR(regmap)) {
108 		ret = PTR_ERR(regmap);
109 		dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
110 			ret);
111 		return ret;
112 	}
113 
114 	ret = regmap_read(regmap, MT6311_SWCID, &data);
115 	if (ret < 0) {
116 		dev_err(&i2c->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
117 		return ret;
118 	}
119 
120 	switch (data) {
121 	case MT6311_E1_CID_CODE:
122 	case MT6311_E2_CID_CODE:
123 	case MT6311_E3_CID_CODE:
124 		break;
125 	default:
126 		dev_err(&i2c->dev, "Unsupported device id = 0x%x.\n", data);
127 		return -ENODEV;
128 	}
129 
130 	for (i = 0; i < MT6311_MAX_REGULATORS; i++) {
131 		config.dev = &i2c->dev;
132 		config.regmap = regmap;
133 
134 		rdev = devm_regulator_register(&i2c->dev,
135 			&mt6311_regulators[i], &config);
136 		if (IS_ERR(rdev)) {
137 			dev_err(&i2c->dev,
138 				"Failed to register MT6311 regulator\n");
139 			return PTR_ERR(rdev);
140 		}
141 	}
142 
143 	return 0;
144 }
145 
146 static const struct i2c_device_id mt6311_i2c_id[] = {
147 	{"mt6311", 0},
148 	{},
149 };
150 MODULE_DEVICE_TABLE(i2c, mt6311_i2c_id);
151 
152 #ifdef CONFIG_OF
153 static const struct of_device_id mt6311_dt_ids[] = {
154 	{ .compatible = "mediatek,mt6311-regulator",
155 	  .data = &mt6311_i2c_id[0] },
156 	{},
157 };
158 MODULE_DEVICE_TABLE(of, mt6311_dt_ids);
159 #endif
160 
161 static struct i2c_driver mt6311_regulator_driver = {
162 	.driver = {
163 		.name = "mt6311",
164 		.of_match_table = of_match_ptr(mt6311_dt_ids),
165 	},
166 	.probe = mt6311_i2c_probe,
167 	.id_table = mt6311_i2c_id,
168 };
169 
170 module_i2c_driver(mt6311_regulator_driver);
171 
172 MODULE_AUTHOR("Henry Chen <henryc.chen@mediatek.com>");
173 MODULE_DESCRIPTION("Regulator device driver for Mediatek MT6311");
174 MODULE_LICENSE("GPL v2");
175