Linux 3.16-rc1
[linux-2.6-block.git] / drivers / regulator / max8952.c
CommitLineData
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1/*
2 * max8952.c - Voltage and current regulation for the Maxim 8952
3 *
4 * Copyright (C) 2010 Samsung Electronics
5 * MyungJoo Ham <myungjoo.ham@samsung.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22#include <linux/module.h>
23#include <linux/init.h>
24#include <linux/i2c.h>
25#include <linux/err.h>
26#include <linux/platform_device.h>
27#include <linux/regulator/driver.h>
28#include <linux/regulator/max8952.h>
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29#include <linux/gpio.h>
30#include <linux/io.h>
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31#include <linux/of.h>
32#include <linux/of_gpio.h>
33#include <linux/regulator/of_regulator.h>
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34#include <linux/slab.h>
35
36/* Registers */
37enum {
38 MAX8952_REG_MODE0,
39 MAX8952_REG_MODE1,
40 MAX8952_REG_MODE2,
41 MAX8952_REG_MODE3,
42 MAX8952_REG_CONTROL,
43 MAX8952_REG_SYNC,
44 MAX8952_REG_RAMP,
45 MAX8952_REG_CHIP_ID1,
46 MAX8952_REG_CHIP_ID2,
47};
48
49struct max8952_data {
50 struct i2c_client *client;
202f4f53 51 struct max8952_platform_data *pdata;
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52
53 bool vid0;
54 bool vid1;
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55};
56
57static int max8952_read_reg(struct max8952_data *max8952, u8 reg)
58{
59 int ret = i2c_smbus_read_byte_data(max8952->client, reg);
a5f8f963 60
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61 if (ret > 0)
62 ret &= 0xff;
63
64 return ret;
65}
66
67static int max8952_write_reg(struct max8952_data *max8952,
68 u8 reg, u8 value)
69{
70 return i2c_smbus_write_byte_data(max8952->client, reg, value);
71}
72
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73static int max8952_list_voltage(struct regulator_dev *rdev,
74 unsigned int selector)
75{
76 struct max8952_data *max8952 = rdev_get_drvdata(rdev);
77
78 if (rdev_get_id(rdev) != 0)
79 return -EINVAL;
80
b9b49af5 81 return (max8952->pdata->dvs_mode[selector] * 10 + 770) * 1000;
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82}
83
b9b49af5 84static int max8952_get_voltage_sel(struct regulator_dev *rdev)
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85{
86 struct max8952_data *max8952 = rdev_get_drvdata(rdev);
87 u8 vid = 0;
88
89 if (max8952->vid0)
90 vid += 1;
91 if (max8952->vid1)
92 vid += 2;
93
b9b49af5 94 return vid;
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95}
96
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97static int max8952_set_voltage_sel(struct regulator_dev *rdev,
98 unsigned selector)
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99{
100 struct max8952_data *max8952 = rdev_get_drvdata(rdev);
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101
102 if (!gpio_is_valid(max8952->pdata->gpio_vid0) ||
e2cf3137 103 !gpio_is_valid(max8952->pdata->gpio_vid1)) {
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104 /* DVS not supported */
105 return -EPERM;
106 }
107
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108 max8952->vid0 = selector & 0x1;
109 max8952->vid1 = (selector >> 1) & 0x1;
110 gpio_set_value(max8952->pdata->gpio_vid0, max8952->vid0);
111 gpio_set_value(max8952->pdata->gpio_vid1, max8952->vid1);
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112
113 return 0;
114}
115
116static struct regulator_ops max8952_ops = {
117 .list_voltage = max8952_list_voltage,
b9b49af5 118 .get_voltage_sel = max8952_get_voltage_sel,
6ea67d04 119 .set_voltage_sel = max8952_set_voltage_sel,
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120};
121
bd6ff0d6 122static const struct regulator_desc regulator = {
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123 .name = "MAX8952_VOUT",
124 .id = 0,
125 .n_voltages = MAX8952_NUM_DVS_MODE,
126 .ops = &max8952_ops,
127 .type = REGULATOR_VOLTAGE,
128 .owner = THIS_MODULE,
129};
130
3ff4aa95 131#ifdef CONFIG_OF
cfe6e333 132static const struct of_device_id max8952_dt_match[] = {
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133 { .compatible = "maxim,max8952" },
134 {},
135};
136MODULE_DEVICE_TABLE(of, max8952_dt_match);
137
138static struct max8952_platform_data *max8952_parse_dt(struct device *dev)
139{
140 struct max8952_platform_data *pd;
141 struct device_node *np = dev->of_node;
142 int ret;
143 int i;
144
145 pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
7752d964 146 if (!pd)
3ff4aa95 147 return NULL;
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148
149 pd->gpio_vid0 = of_get_named_gpio(np, "max8952,vid-gpios", 0);
150 pd->gpio_vid1 = of_get_named_gpio(np, "max8952,vid-gpios", 1);
151 pd->gpio_en = of_get_named_gpio(np, "max8952,en-gpio", 0);
152
153 if (of_property_read_u32(np, "max8952,default-mode", &pd->default_mode))
154 dev_warn(dev, "Default mode not specified, assuming 0\n");
155
156 ret = of_property_read_u32_array(np, "max8952,dvs-mode-microvolt",
157 pd->dvs_mode, ARRAY_SIZE(pd->dvs_mode));
158 if (ret) {
159 dev_err(dev, "max8952,dvs-mode-microvolt property not specified");
160 return NULL;
161 }
162
163 for (i = 0; i < ARRAY_SIZE(pd->dvs_mode); ++i) {
164 if (pd->dvs_mode[i] < 770000 || pd->dvs_mode[i] > 1400000) {
165 dev_err(dev, "DVS voltage %d out of range\n", i);
166 return NULL;
167 }
168 pd->dvs_mode[i] = (pd->dvs_mode[i] - 770000) / 10000;
169 }
170
171 if (of_property_read_u32(np, "max8952,sync-freq", &pd->sync_freq))
172 dev_warn(dev, "max8952,sync-freq property not specified, defaulting to 26MHz\n");
173
174 if (of_property_read_u32(np, "max8952,ramp-speed", &pd->ramp_speed))
175 dev_warn(dev, "max8952,ramp-speed property not specified, defaulting to 32mV/us\n");
176
177 pd->reg_data = of_get_regulator_init_data(dev, np);
178 if (!pd->reg_data) {
179 dev_err(dev, "Failed to parse regulator init data\n");
180 return NULL;
181 }
182
183 return pd;
184}
185#else
186static struct max8952_platform_data *max8952_parse_dt(struct device *dev)
187{
188 return NULL;
189}
190#endif
191
a5023574 192static int max8952_pmic_probe(struct i2c_client *client,
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193 const struct i2c_device_id *i2c_id)
194{
195 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
dff91d0b 196 struct max8952_platform_data *pdata = dev_get_platdata(&client->dev);
c172708d 197 struct regulator_config config = { };
202f4f53 198 struct max8952_data *max8952;
b874f41c 199 struct regulator_dev *rdev;
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200
201 int ret = 0, err = 0;
202
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203 if (client->dev.of_node)
204 pdata = max8952_parse_dt(&client->dev);
205
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206 if (!pdata) {
207 dev_err(&client->dev, "Require the platform data\n");
208 return -EINVAL;
209 }
210
211 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
212 return -EIO;
213
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214 max8952 = devm_kzalloc(&client->dev, sizeof(struct max8952_data),
215 GFP_KERNEL);
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216 if (!max8952)
217 return -ENOMEM;
218
219 max8952->client = client;
202f4f53 220 max8952->pdata = pdata;
202f4f53 221
b874f41c 222 config.dev = &client->dev;
3ec6eb9c 223 config.init_data = pdata->reg_data;
c172708d 224 config.driver_data = max8952;
71622e15 225 config.of_node = client->dev.of_node;
c172708d 226
b669e0ad 227 config.ena_gpio = pdata->gpio_en;
3ec6eb9c 228 if (pdata->reg_data->constraints.boot_on)
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229 config.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
230
b874f41c 231 rdev = devm_regulator_register(&client->dev, &regulator, &config);
202f4f53 232
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233 if (IS_ERR(rdev)) {
234 ret = PTR_ERR(rdev);
235 dev_err(&client->dev, "regulator init failed (%d)\n", ret);
372de4aa 236 return ret;
da05738e 237 }
202f4f53 238
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239 max8952->vid0 = pdata->default_mode & 0x1;
240 max8952->vid1 = (pdata->default_mode >> 1) & 0x1;
202f4f53 241
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242 if (gpio_is_valid(pdata->gpio_vid0) &&
243 gpio_is_valid(pdata->gpio_vid1)) {
244 if (!gpio_request(pdata->gpio_vid0, "MAX8952 VID0"))
245 gpio_direction_output(pdata->gpio_vid0,
c8237f01 246 (pdata->default_mode) & 0x1);
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247 else
248 err = 1;
249
250 if (!gpio_request(pdata->gpio_vid1, "MAX8952 VID1"))
251 gpio_direction_output(pdata->gpio_vid1,
c8237f01 252 (pdata->default_mode >> 1) & 0x1);
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253 else {
254 if (!err)
255 gpio_free(pdata->gpio_vid0);
256 err = 2;
257 }
258
259 } else
260 err = 3;
261
262 if (err) {
b874f41c 263 dev_warn(&client->dev, "VID0/1 gpio invalid: "
25985edc 264 "DVS not available.\n");
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265 max8952->vid0 = 0;
266 max8952->vid1 = 0;
267 /* Mark invalid */
268 pdata->gpio_vid0 = -1;
269 pdata->gpio_vid1 = -1;
270
271 /* Disable Pulldown of EN only */
272 max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x60);
273
b874f41c 274 dev_err(&client->dev, "DVS modes disabled because VID0 and VID1"
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275 " do not have proper controls.\n");
276 } else {
277 /*
278 * Disable Pulldown on EN, VID0, VID1 to reduce
279 * leakage current of MAX8952 assuming that MAX8952
280 * is turned on (EN==1). Note that without having VID0/1
281 * properly connected, turning pulldown off can be
282 * problematic. Thus, turn this off only when they are
283 * controllable by GPIO.
284 */
285 max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x0);
286 }
287
288 max8952_write_reg(max8952, MAX8952_REG_MODE0,
289 (max8952_read_reg(max8952,
290 MAX8952_REG_MODE0) & 0xC0) |
291 (pdata->dvs_mode[0] & 0x3F));
292 max8952_write_reg(max8952, MAX8952_REG_MODE1,
293 (max8952_read_reg(max8952,
294 MAX8952_REG_MODE1) & 0xC0) |
295 (pdata->dvs_mode[1] & 0x3F));
296 max8952_write_reg(max8952, MAX8952_REG_MODE2,
297 (max8952_read_reg(max8952,
298 MAX8952_REG_MODE2) & 0xC0) |
299 (pdata->dvs_mode[2] & 0x3F));
300 max8952_write_reg(max8952, MAX8952_REG_MODE3,
301 (max8952_read_reg(max8952,
302 MAX8952_REG_MODE3) & 0xC0) |
303 (pdata->dvs_mode[3] & 0x3F));
304
305 max8952_write_reg(max8952, MAX8952_REG_SYNC,
306 (max8952_read_reg(max8952, MAX8952_REG_SYNC) & 0x3F) |
307 ((pdata->sync_freq & 0x3) << 6));
308 max8952_write_reg(max8952, MAX8952_REG_RAMP,
309 (max8952_read_reg(max8952, MAX8952_REG_RAMP) & 0x1F) |
310 ((pdata->ramp_speed & 0x7) << 5));
311
312 i2c_set_clientdata(client, max8952);
313
da05738e 314 return 0;
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315}
316
8dc995f5 317static int max8952_pmic_remove(struct i2c_client *client)
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318{
319 struct max8952_data *max8952 = i2c_get_clientdata(client);
320 struct max8952_platform_data *pdata = max8952->pdata;
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321
322 gpio_free(pdata->gpio_vid0);
323 gpio_free(pdata->gpio_vid1);
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324 return 0;
325}
326
327static const struct i2c_device_id max8952_ids[] = {
328 { "max8952", 0 },
329 { },
330};
331MODULE_DEVICE_TABLE(i2c, max8952_ids);
332
333static struct i2c_driver max8952_pmic_driver = {
334 .probe = max8952_pmic_probe,
5eb9f2b9 335 .remove = max8952_pmic_remove,
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336 .driver = {
337 .name = "max8952",
3ff4aa95 338 .of_match_table = of_match_ptr(max8952_dt_match),
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339 },
340 .id_table = max8952_ids,
341};
342
343static int __init max8952_pmic_init(void)
344{
345 return i2c_add_driver(&max8952_pmic_driver);
346}
347subsys_initcall(max8952_pmic_init);
348
349static void __exit max8952_pmic_exit(void)
350{
351 i2c_del_driver(&max8952_pmic_driver);
352}
353module_exit(max8952_pmic_exit);
354
355MODULE_DESCRIPTION("MAXIM 8952 voltage regulator driver");
356MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
357MODULE_LICENSE("GPL");