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/delay.h>
28#include <linux/platform_device.h>
29#include <linux/regulator/driver.h>
30#include <linux/regulator/machine.h>
31#include <linux/mfd/aat2870.h>
32
33struct aat2870_regulator {
34	struct platform_device *pdev;
35	struct regulator_desc desc;
36
37	const int *voltages; /* uV */
38
39	int min_uV;
40	int max_uV;
41
42	u8 enable_addr;
43	u8 enable_shift;
44	u8 enable_mask;
45
46	u8 voltage_addr;
47	u8 voltage_shift;
48	u8 voltage_mask;
49};
50
51static int aat2870_ldo_list_voltage(struct regulator_dev *rdev,
52				    unsigned selector)
53{
54	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
55
56	return ri->voltages[selector];
57}
58
59static int aat2870_ldo_set_voltage_sel(struct regulator_dev *rdev,
60				       unsigned selector)
61{
62	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
63	struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
64
65	return aat2870->update(aat2870, ri->voltage_addr, ri->voltage_mask,
66			       selector << ri->voltage_shift);
67}
68
69static int aat2870_ldo_get_voltage_sel(struct regulator_dev *rdev)
70{
71	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
72	struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
73	u8 val;
74	int ret;
75
76	ret = aat2870->read(aat2870, ri->voltage_addr, &val);
77	if (ret)
78		return ret;
79
80	return (val & ri->voltage_mask) >> ri->voltage_shift;
81}
82
83static int aat2870_ldo_enable(struct regulator_dev *rdev)
84{
85	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
86	struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
87
88	return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask,
89			       ri->enable_mask);
90}
91
92static int aat2870_ldo_disable(struct regulator_dev *rdev)
93{
94	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
95	struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
96
97	return aat2870->update(aat2870, ri->enable_addr, ri->enable_mask, 0);
98}
99
100static int aat2870_ldo_is_enabled(struct regulator_dev *rdev)
101{
102	struct aat2870_regulator *ri = rdev_get_drvdata(rdev);
103	struct aat2870_data *aat2870 = dev_get_drvdata(ri->pdev->dev.parent);
104	u8 val;
105	int ret;
106
107	ret = aat2870->read(aat2870, ri->enable_addr, &val);
108	if (ret)
109		return ret;
110
111	return val & ri->enable_mask ? 1 : 0;
112}
113
114static struct regulator_ops aat2870_ldo_ops = {
115	.list_voltage = aat2870_ldo_list_voltage,
116	.set_voltage_sel = aat2870_ldo_set_voltage_sel,
117	.get_voltage_sel = aat2870_ldo_get_voltage_sel,
118	.enable = aat2870_ldo_enable,
119	.disable = aat2870_ldo_disable,
120	.is_enabled = aat2870_ldo_is_enabled,
121};
122
123static const int aat2870_ldo_voltages[] = {
124	1200000, 1300000, 1500000, 1600000,
125	1800000, 2000000, 2200000, 2500000,
126	2600000, 2700000, 2800000, 2900000,
127	3000000, 3100000, 3200000, 3300000,
128};
129
130#define AAT2870_LDO(ids)				\
131	{						\
132		.desc = {				\
133			.name = #ids,			\
134			.id = AAT2870_ID_##ids,		\
135			.n_voltages = ARRAY_SIZE(aat2870_ldo_voltages),	\
136			.ops = &aat2870_ldo_ops,	\
137			.type = REGULATOR_VOLTAGE,	\
138			.owner = THIS_MODULE,		\
139		},					\
140		.voltages = aat2870_ldo_voltages,	\
141		.min_uV = 1200000,			\
142		.max_uV = 3300000,			\
143	}
144
145static struct aat2870_regulator aat2870_regulators[] = {
146	AAT2870_LDO(LDOA),
147	AAT2870_LDO(LDOB),
148	AAT2870_LDO(LDOC),
149	AAT2870_LDO(LDOD),
150};
151
152static struct aat2870_regulator *aat2870_get_regulator(int id)
153{
154	struct aat2870_regulator *ri = NULL;
155	int i;
156
157	for (i = 0; i < ARRAY_SIZE(aat2870_regulators); i++) {
158		ri = &aat2870_regulators[i];
159		if (ri->desc.id == id)
160			break;
161	}
162
163	if (i == ARRAY_SIZE(aat2870_regulators))
164		return NULL;
165
166	ri->enable_addr = AAT2870_LDO_EN;
167	ri->enable_shift = id - AAT2870_ID_LDOA;
168	ri->enable_mask = 0x1 << ri->enable_shift;
169
170	ri->voltage_addr = (id - AAT2870_ID_LDOA) / 2 ?
171			   AAT2870_LDO_CD : AAT2870_LDO_AB;
172	ri->voltage_shift = (id - AAT2870_ID_LDOA) % 2 ? 0 : 4;
173	ri->voltage_mask = 0xF << ri->voltage_shift;
174
175	return ri;
176}
177
178static int aat2870_regulator_probe(struct platform_device *pdev)
179{
180	struct aat2870_regulator *ri;
181	struct regulator_dev *rdev;
182
183	ri = aat2870_get_regulator(pdev->id);
184	if (!ri) {
185		dev_err(&pdev->dev, "Invalid device ID, %d\n", pdev->id);
186		return -EINVAL;
187	}
188	ri->pdev = pdev;
189
190	rdev = regulator_register(&ri->desc, &pdev->dev,
191				  pdev->dev.platform_data, ri, NULL);
192	if (IS_ERR(rdev)) {
193		dev_err(&pdev->dev, "Failed to register regulator %s\n",
194			ri->desc.name);
195		return PTR_ERR(rdev);
196	}
197	platform_set_drvdata(pdev, rdev);
198
199	return 0;
200}
201
202static int __devexit aat2870_regulator_remove(struct platform_device *pdev)
203{
204	struct regulator_dev *rdev = platform_get_drvdata(pdev);
205
206	regulator_unregister(rdev);
207	return 0;
208}
209
210static struct platform_driver aat2870_regulator_driver = {
211	.driver = {
212		.name	= "aat2870-regulator",
213		.owner	= THIS_MODULE,
214	},
215	.probe	= aat2870_regulator_probe,
216	.remove	= __devexit_p(aat2870_regulator_remove),
217};
218
219static int __init aat2870_regulator_init(void)
220{
221	return platform_driver_register(&aat2870_regulator_driver);
222}
223subsys_initcall(aat2870_regulator_init);
224
225static void __exit aat2870_regulator_exit(void)
226{
227	platform_driver_unregister(&aat2870_regulator_driver);
228}
229module_exit(aat2870_regulator_exit);
230
231MODULE_DESCRIPTION("AnalogicTech AAT2870 Regulator");
232MODULE_LICENSE("GPL");
233MODULE_AUTHOR("Jin Park <jinyoungp@nvidia.com>");
234