2 * Regulators driver for Maxim max8649
4 * Copyright (C) 2009-2010 Marvell International Ltd.
5 * Haojian Zhuang <haojian.zhuang@marvell.com>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/err.h>
14 #include <linux/i2c.h>
15 #include <linux/platform_device.h>
16 #include <linux/regulator/driver.h>
17 #include <linux/slab.h>
18 #include <linux/regulator/max8649.h>
19 #include <linux/regmap.h>
21 #define MAX8649_DCDC_VMIN 750000 /* uV */
22 #define MAX8649_DCDC_VMAX 1380000 /* uV */
23 #define MAX8649_DCDC_STEP 10000 /* uV */
24 #define MAX8649_VOL_MASK 0x3f
27 #define MAX8649_MODE0 0x00
28 #define MAX8649_MODE1 0x01
29 #define MAX8649_MODE2 0x02
30 #define MAX8649_MODE3 0x03
31 #define MAX8649_CONTROL 0x04
32 #define MAX8649_SYNC 0x05
33 #define MAX8649_RAMP 0x06
34 #define MAX8649_CHIP_ID1 0x08
35 #define MAX8649_CHIP_ID2 0x09
38 #define MAX8649_EN_PD (1 << 7)
39 #define MAX8649_VID0_PD (1 << 6)
40 #define MAX8649_VID1_PD (1 << 5)
41 #define MAX8649_VID_MASK (3 << 5)
43 #define MAX8649_FORCE_PWM (1 << 7)
44 #define MAX8649_SYNC_EXTCLK (1 << 6)
46 #define MAX8649_EXT_MASK (3 << 6)
48 #define MAX8649_RAMP_MASK (7 << 5)
49 #define MAX8649_RAMP_DOWN (1 << 1)
51 struct max8649_regulator_info {
52 struct regulator_dev *regulator;
54 struct regmap *regmap;
57 unsigned mode:2; /* bit[1:0] = VID1, VID0 */
58 unsigned extclk_freq:2;
60 unsigned ramp_timing:3;
66 static inline int check_range(int min_uV, int max_uV)
68 if ((min_uV < MAX8649_DCDC_VMIN) || (max_uV > MAX8649_DCDC_VMAX)
74 static int max8649_list_voltage(struct regulator_dev *rdev, unsigned index)
76 return (MAX8649_DCDC_VMIN + index * MAX8649_DCDC_STEP);
79 static int max8649_get_voltage(struct regulator_dev *rdev)
81 struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
86 ret = regmap_read(info->regmap, info->vol_reg, &val);
89 data = (unsigned char)val & MAX8649_VOL_MASK;
90 return max8649_list_voltage(rdev, data);
93 static int max8649_set_voltage(struct regulator_dev *rdev,
94 int min_uV, int max_uV, unsigned *selector)
96 struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
97 unsigned char data, mask;
99 if (check_range(min_uV, max_uV)) {
100 dev_err(info->dev, "invalid voltage range (%d, %d) uV\n",
104 data = (min_uV - MAX8649_DCDC_VMIN + MAX8649_DCDC_STEP - 1)
106 mask = MAX8649_VOL_MASK;
107 *selector = data & mask;
109 return regmap_update_bits(info->regmap, info->vol_reg, mask, data);
112 /* EN_PD means pulldown on EN input */
113 static int max8649_enable(struct regulator_dev *rdev)
115 struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
116 return regmap_update_bits(info->regmap, MAX8649_CONTROL, MAX8649_EN_PD, 0);
120 * Applied internal pulldown resistor on EN input pin.
121 * If pulldown EN pin outside, it would be better.
123 static int max8649_disable(struct regulator_dev *rdev)
125 struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
126 return regmap_update_bits(info->regmap, MAX8649_CONTROL, MAX8649_EN_PD,
130 static int max8649_is_enabled(struct regulator_dev *rdev)
132 struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
136 ret = regmap_read(info->regmap, MAX8649_CONTROL, &val);
139 return !((unsigned char)val & MAX8649_EN_PD);
142 static int max8649_enable_time(struct regulator_dev *rdev)
144 struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
145 int voltage, rate, ret;
149 ret = regmap_read(info->regmap, info->vol_reg, &val);
152 val &= MAX8649_VOL_MASK;
153 voltage = max8649_list_voltage(rdev, (unsigned char)ret); /* uV */
156 ret = regmap_read(info->regmap, MAX8649_RAMP, &val);
159 ret = (val & MAX8649_RAMP_MASK) >> 5;
160 rate = (32 * 1000) >> ret; /* uV/uS */
162 return DIV_ROUND_UP(voltage, rate);
165 static int max8649_set_mode(struct regulator_dev *rdev, unsigned int mode)
167 struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
170 case REGULATOR_MODE_FAST:
171 regmap_update_bits(info->regmap, info->vol_reg, MAX8649_FORCE_PWM,
174 case REGULATOR_MODE_NORMAL:
175 regmap_update_bits(info->regmap, info->vol_reg,
176 MAX8649_FORCE_PWM, 0);
184 static unsigned int max8649_get_mode(struct regulator_dev *rdev)
186 struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
190 ret = regmap_read(info->regmap, info->vol_reg, &val);
193 if (val & MAX8649_FORCE_PWM)
194 return REGULATOR_MODE_FAST;
195 return REGULATOR_MODE_NORMAL;
198 static struct regulator_ops max8649_dcdc_ops = {
199 .set_voltage = max8649_set_voltage,
200 .get_voltage = max8649_get_voltage,
201 .list_voltage = max8649_list_voltage,
202 .enable = max8649_enable,
203 .disable = max8649_disable,
204 .is_enabled = max8649_is_enabled,
205 .enable_time = max8649_enable_time,
206 .set_mode = max8649_set_mode,
207 .get_mode = max8649_get_mode,
211 static struct regulator_desc dcdc_desc = {
213 .ops = &max8649_dcdc_ops,
214 .type = REGULATOR_VOLTAGE,
215 .n_voltages = 1 << 6,
216 .owner = THIS_MODULE,
219 static struct regmap_config max8649_regmap_config = {
224 static int __devinit max8649_regulator_probe(struct i2c_client *client,
225 const struct i2c_device_id *id)
227 struct max8649_platform_data *pdata = client->dev.platform_data;
228 struct max8649_regulator_info *info = NULL;
233 info = kzalloc(sizeof(struct max8649_regulator_info), GFP_KERNEL);
235 dev_err(&client->dev, "No enough memory\n");
239 info->regmap = regmap_init_i2c(client, &max8649_regmap_config);
240 if (IS_ERR(info->regmap)) {
241 ret = PTR_ERR(info->regmap);
242 dev_err(&client->dev, "Failed to allocate register map: %d\n", ret);
246 info->dev = &client->dev;
247 i2c_set_clientdata(client, info);
249 info->mode = pdata->mode;
250 switch (info->mode) {
252 info->vol_reg = MAX8649_MODE0;
255 info->vol_reg = MAX8649_MODE1;
258 info->vol_reg = MAX8649_MODE2;
261 info->vol_reg = MAX8649_MODE3;
267 ret = regmap_read(info->regmap, MAX8649_CHIP_ID1, &val);
269 dev_err(info->dev, "Failed to detect ID of MAX8649:%d\n",
273 dev_info(info->dev, "Detected MAX8649 (ID:%x)\n", ret);
275 /* enable VID0 & VID1 */
276 regmap_update_bits(info->regmap, MAX8649_CONTROL, MAX8649_VID_MASK, 0);
278 /* enable/disable external clock synchronization */
279 info->extclk = pdata->extclk;
280 data = (info->extclk) ? MAX8649_SYNC_EXTCLK : 0;
281 regmap_update_bits(info->regmap, info->vol_reg, MAX8649_SYNC_EXTCLK, data);
283 /* set external clock frequency */
284 info->extclk_freq = pdata->extclk_freq;
285 regmap_update_bits(info->regmap, MAX8649_SYNC, MAX8649_EXT_MASK,
286 info->extclk_freq << 6);
289 if (pdata->ramp_timing) {
290 info->ramp_timing = pdata->ramp_timing;
291 regmap_update_bits(info->regmap, MAX8649_RAMP, MAX8649_RAMP_MASK,
292 info->ramp_timing << 5);
295 info->ramp_down = pdata->ramp_down;
296 if (info->ramp_down) {
297 regmap_update_bits(info->regmap, MAX8649_RAMP, MAX8649_RAMP_DOWN,
301 info->regulator = regulator_register(&dcdc_desc, &client->dev,
302 pdata->regulator, info, NULL);
303 if (IS_ERR(info->regulator)) {
304 dev_err(info->dev, "failed to register regulator %s\n",
306 ret = PTR_ERR(info->regulator);
310 dev_info(info->dev, "Max8649 regulator device is detected.\n");
313 regmap_exit(info->regmap);
319 static int __devexit max8649_regulator_remove(struct i2c_client *client)
321 struct max8649_regulator_info *info = i2c_get_clientdata(client);
325 regulator_unregister(info->regulator);
326 regmap_exit(info->regmap);
333 static const struct i2c_device_id max8649_id[] = {
337 MODULE_DEVICE_TABLE(i2c, max8649_id);
339 static struct i2c_driver max8649_driver = {
340 .probe = max8649_regulator_probe,
341 .remove = __devexit_p(max8649_regulator_remove),
345 .id_table = max8649_id,
348 static int __init max8649_init(void)
350 return i2c_add_driver(&max8649_driver);
352 subsys_initcall(max8649_init);
354 static void __exit max8649_exit(void)
356 i2c_del_driver(&max8649_driver);
358 module_exit(max8649_exit);
360 /* Module information */
361 MODULE_DESCRIPTION("MAXIM 8649 voltage regulator driver");
362 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
363 MODULE_LICENSE("GPL");