1 /*
2  * linux/drivers/regulator/aat2870-regulator.c
3  *
4  * Copyright (c) 2011, NVIDIA Corporation.
5  * Author: Jin Park <jinyoungp@nvidia.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * version 2 as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
19  * 02110-1301 USA
20  */
21 
22 #include <linux/kernel.h>
23 #include <linux/init.h>
24 #include <linux/err.h>
25 #include <linux/module.h>
26 #include <linux/slab.h>
27 #include <linux/platform_device.h>
28 #include <linux/regulator/driver.h>
29 #include <linux/regulator/machine.h>
30 #include <linux/mfd/aat2870.h>
31 
32 struct aat2870_regulator {
33 	struct aat2870_data *aat2870;
34 	struct regulator_desc desc;
35 
36 	u8 enable_addr;
37 	u8 enable_shift;
38 	u8 enable_mask;
39 
40 	u8 voltage_addr;
41 	u8 voltage_shift;
42 	u8 voltage_mask;
43 };
44 
45 static int aat2870_ldo_set_voltage_sel(struct regulator_dev *rdev,
46 				       unsigned selector)
47 {
48 	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
49 	struct aat2870_data *aat2870 = ri->aat2870;
50 
51 	return aat2870->update(aat2870, ri->voltage_addr, ri->voltage_mask,
52 			       selector << ri->voltage_shift);
53 }
54 
55 static int aat2870_ldo_get_voltage_sel(struct regulator_dev *rdev)
56 {
57 	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
58 	struct aat2870_data *aat2870 = ri->aat2870;
59 	u8 val;
60 	int ret;
61 
62 	ret = aat2870->read(aat2870, ri->voltage_addr, &val);
63 	if (ret)
64 		return ret;
65 
66 	return (val & ri->voltage_mask) >> ri->voltage_shift;
67 }
68 
69 static int aat2870_ldo_enable(struct regulator_dev *rdev)
70 {
71 	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
72 	struct aat2870_data *aat2870 = ri->aat2870;
73 
74 	return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask,
75 			       ri->enable_mask);
76 }
77 
78 static int aat2870_ldo_disable(struct regulator_dev *rdev)
79 {
80 	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
81 	struct aat2870_data *aat2870 = ri->aat2870;
82 
83 	return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask, 0);
84 }
85 
86 static int aat2870_ldo_is_enabled(struct regulator_dev *rdev)
87 {
88 	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
89 	struct aat2870_data *aat2870 = ri->aat2870;
90 	u8 val;
91 	int ret;
92 
93 	ret = aat2870->read(aat2870, ri->enable_addr, &val);
94 	if (ret)
95 		return ret;
96 
97 	return val & ri->enable_mask ? 1 : 0;
98 }
99 
100 static const struct regulator_ops aat2870_ldo_ops = {
101 	.list_voltage = regulator_list_voltage_table,
102 	.map_voltage = regulator_map_voltage_ascend,
103 	.set_voltage_sel = aat2870_ldo_set_voltage_sel,
104 	.get_voltage_sel = aat2870_ldo_get_voltage_sel,
105 	.enable = aat2870_ldo_enable,
106 	.disable = aat2870_ldo_disable,
107 	.is_enabled = aat2870_ldo_is_enabled,
108 };
109 
110 static const unsigned int aat2870_ldo_voltages[] = {
111 	1200000, 1300000, 1500000, 1600000,
112 	1800000, 2000000, 2200000, 2500000,
113 	2600000, 2700000, 2800000, 2900000,
114 	3000000, 3100000, 3200000, 3300000,
115 };
116 
117 #define AAT2870_LDO(ids)				\
118 	{						\
119 		.desc = {				\
120 			.name = #ids,			\
121 			.id = AAT2870_ID_##ids,		\
122 			.n_voltages = ARRAY_SIZE(aat2870_ldo_voltages),	\
123 			.volt_table = aat2870_ldo_voltages, \
124 			.ops = &aat2870_ldo_ops,	\
125 			.type = REGULATOR_VOLTAGE,	\
126 			.owner = THIS_MODULE,		\
127 		},					\
128 	}
129 
130 static struct aat2870_regulator aat2870_regulators[] = {
131 	AAT2870_LDO(LDOA),
132 	AAT2870_LDO(LDOB),
133 	AAT2870_LDO(LDOC),
134 	AAT2870_LDO(LDOD),
135 };
136 
137 static struct aat2870_regulator *aat2870_get_regulator(int id)
138 {
139 	struct aat2870_regulator *ri = NULL;
140 	int i;
141 
142 	for (i = 0; i < ARRAY_SIZE(aat2870_regulators); i++) {
143 		ri = &aat2870_regulators[i];
144 		if (ri->desc.id == id)
145 			break;
146 	}
147 
148 	if (i == ARRAY_SIZE(aat2870_regulators))
149 		return NULL;
150 
151 	ri->enable_addr = AAT2870_LDO_EN;
152 	ri->enable_shift = id - AAT2870_ID_LDOA;
153 	ri->enable_mask = 0x1 << ri->enable_shift;
154 
155 	ri->voltage_addr = (id - AAT2870_ID_LDOA) / 2 ?
156 			   AAT2870_LDO_CD : AAT2870_LDO_AB;
157 	ri->voltage_shift = (id - AAT2870_ID_LDOA) % 2 ? 0 : 4;
158 	ri->voltage_mask = 0xF << ri->voltage_shift;
159 
160 	return ri;
161 }
162 
163 static int aat2870_regulator_probe(struct platform_device *pdev)
164 {
165 	struct aat2870_regulator *ri;
166 	struct regulator_config config = { };
167 	struct regulator_dev *rdev;
168 
169 	ri = aat2870_get_regulator(pdev->id);
170 	if (!ri) {
171 		dev_err(&pdev->dev, "Invalid device ID, %d\n", pdev->id);
172 		return -EINVAL;
173 	}
174 	ri->aat2870 = dev_get_drvdata(pdev->dev.parent);
175 
176 	config.dev = &pdev->dev;
177 	config.driver_data = ri;
178 	config.init_data = dev_get_platdata(&pdev->dev);
179 
180 	rdev = devm_regulator_register(&pdev->dev, &ri->desc, &config);
181 	if (IS_ERR(rdev)) {
182 		dev_err(&pdev->dev, "Failed to register regulator %s\n",
183 			ri->desc.name);
184 		return PTR_ERR(rdev);
185 	}
186 	platform_set_drvdata(pdev, rdev);
187 
188 	return 0;
189 }
190 
191 static struct platform_driver aat2870_regulator_driver = {
192 	.driver = {
193 		.name	= "aat2870-regulator",
194 	},
195 	.probe	= aat2870_regulator_probe,
196 };
197 
198 static int __init aat2870_regulator_init(void)
199 {
200 	return platform_driver_register(&aat2870_regulator_driver);
201 }
202 subsys_initcall(aat2870_regulator_init);
203 
204 static void __exit aat2870_regulator_exit(void)
205 {
206 	platform_driver_unregister(&aat2870_regulator_driver);
207 }
208 module_exit(aat2870_regulator_exit);
209 
210 MODULE_DESCRIPTION("AnalogicTech AAT2870 Regulator");
211 MODULE_LICENSE("GPL");
212 MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");
213 MODULE_ALIAS("platform:aat2870-regulator");
214