drivers/regulator/max8925-regulator.c

   1 /*
   2  * Regulators driver for Maxim max8925
   3  *
   4  * Copyright (C) 2009 Marvell International Ltd.
   5  *      Haojian Zhuang <haojian.zhuang@marvell.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 version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/err.h>
  15 #include <linux/i2c.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/regulator/driver.h>
  18 #include <linux/regulator/machine.h>
  19 #include <linux/mfd/max8925.h>
  20
  21 #define SD1_DVM_VMIN            850000
  22 #define SD1_DVM_VMAX            1000000
  23 #define SD1_DVM_STEP            50000
  24 #define SD1_DVM_SHIFT           5               /* SDCTL1 bit5 */
  25 #define SD1_DVM_EN              6               /* SDV1 bit 6 */
  26
  27 /* bit definitions in LDO control registers */
  28 #define LDO_SEQ_I2C             0x7             /* Power U/D by i2c */
  29 #define LDO_SEQ_MASK            0x7             /* Power U/D sequence mask */
  30 #define LDO_SEQ_SHIFT           2               /* Power U/D sequence offset */
  31 #define LDO_I2C_EN              0x1             /* Enable by i2c */
  32 #define LDO_I2C_EN_MASK         0x1             /* Enable mask by i2c */
  33 #define LDO_I2C_EN_SHIFT        0               /* Enable offset by i2c */
  34
  35 struct max8925_regulator_info {
  36         struct regulator_desc   desc;
  37         struct regulator_dev    *regulator;
  38         struct i2c_client       *i2c;
  39         struct max8925_chip     *chip;
  40
  41         int     min_uV;
  42         int     max_uV;
  43         int     step_uV;
  44         int     vol_reg;
  45         int     vol_shift;
  46         int     vol_nbits;
  47         int     enable_reg;
  48 };
  49
  50 static inline int check_range(struct max8925_regulator_info *info,
  51                               int min_uV, int max_uV)
  52 {
  53         if (min_uV < info->min_uV || min_uV > info->max_uV)
  54                 return -EINVAL;
  55
  56         return 0;
  57 }
  58
  59 static int max8925_list_voltage(struct regulator_dev *rdev, unsigned index)
  60 {
  61         struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
  62         return info->min_uV + index * info->step_uV;
  63 }
  64
  65 static int max8925_set_voltage(struct regulator_dev *rdev,
  66                                int min_uV, int max_uV, unsigned int *selector)
  67 {
  68         struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
  69         unsigned char data, mask;
  70
  71         if (check_range(info, min_uV, max_uV)) {
  72                 dev_err(info->chip->dev, "invalid voltage range (%d, %d) uV\n",
  73                         min_uV, max_uV);
  74                 return -EINVAL;
  75         }
  76         data = (min_uV - info->min_uV + info->step_uV - 1) / info->step_uV;
  77         *selector = data;
  78         data <<= info->vol_shift;
  79         mask = ((1 << info->vol_nbits) - 1) << info->vol_shift;
  80
  81         return max8925_set_bits(info->i2c, info->vol_reg, mask, data);
  82 }
  83
  84 static int max8925_get_voltage(struct regulator_dev *rdev)
  85 {
  86         struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
  87         unsigned char data, mask;
  88         int ret;
  89
  90         ret = max8925_reg_read(info->i2c, info->vol_reg);
  91         if (ret < 0)
  92                 return ret;
  93         mask = ((1 << info->vol_nbits) - 1) << info->vol_shift;
  94         data = (ret & mask) >> info->vol_shift;
  95
  96         return max8925_list_voltage(rdev, data);
  97 }
  98
  99 static int max8925_enable(struct regulator_dev *rdev)
 100 {
 101         struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
 102
 103         return max8925_set_bits(info->i2c, info->enable_reg,
 104                                 LDO_SEQ_MASK << LDO_SEQ_SHIFT |
 105                                 LDO_I2C_EN_MASK << LDO_I2C_EN_SHIFT,
 106                                 LDO_SEQ_I2C << LDO_SEQ_SHIFT |
 107                                 LDO_I2C_EN << LDO_I2C_EN_SHIFT);
 108 }
 109
 110 static int max8925_disable(struct regulator_dev *rdev)
 111 {
 112         struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
 113
 114         return max8925_set_bits(info->i2c, info->enable_reg,
 115                                 LDO_SEQ_MASK << LDO_SEQ_SHIFT |
 116                                 LDO_I2C_EN_MASK << LDO_I2C_EN_SHIFT,
 117                                 LDO_SEQ_I2C << LDO_SEQ_SHIFT);
 118 }
 119
 120 static int max8925_is_enabled(struct regulator_dev *rdev)
 121 {
 122         struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
 123         int ldo_seq, ret;
 124
 125         ret = max8925_reg_read(info->i2c, info->enable_reg);
 126         if (ret < 0)
 127                 return ret;
 128         ldo_seq = (ret >> LDO_SEQ_SHIFT) & LDO_SEQ_MASK;
 129         if (ldo_seq != LDO_SEQ_I2C)
 130                 return 1;
 131         else
 132                 return ret & (LDO_I2C_EN_MASK << LDO_I2C_EN_SHIFT);
 133 }
 134
 135 static int max8925_set_dvm_voltage(struct regulator_dev *rdev, int uV)
 136 {
 137         struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
 138         unsigned char data, mask;
 139
 140         if (uV < SD1_DVM_VMIN || uV > SD1_DVM_VMAX)
 141                 return -EINVAL;
 142
 143         data = (uV - SD1_DVM_VMIN + SD1_DVM_STEP - 1) / SD1_DVM_STEP;
 144         data <<= SD1_DVM_SHIFT;
 145         mask = 3 << SD1_DVM_SHIFT;
 146
 147         return max8925_set_bits(info->i2c, info->enable_reg, mask, data);
 148 }
 149
 150 static int max8925_set_dvm_enable(struct regulator_dev *rdev)
 151 {
 152         struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
 153
 154         return max8925_set_bits(info->i2c, info->vol_reg, 1 << SD1_DVM_EN,
 155                                 1 << SD1_DVM_EN);
 156 }
 157
 158 static int max8925_set_dvm_disable(struct regulator_dev *rdev)
 159 {
 160         struct max8925_regulator_info *info = rdev_get_drvdata(rdev);
 161
 162         return max8925_set_bits(info->i2c, info->vol_reg, 1 << SD1_DVM_EN, 0);
 163 }
 164
 165 static struct regulator_ops max8925_regulator_sdv_ops = {
 166         .set_voltage            = max8925_set_voltage,
 167         .get_voltage            = max8925_get_voltage,
 168         .enable                 = max8925_enable,
 169         .disable                = max8925_disable,
 170         .is_enabled             = max8925_is_enabled,
 171         .set_suspend_voltage    = max8925_set_dvm_voltage,
 172         .set_suspend_enable     = max8925_set_dvm_enable,
 173         .set_suspend_disable    = max8925_set_dvm_disable,
 174 };
 175
 176 static struct regulator_ops max8925_regulator_ldo_ops = {
 177         .set_voltage            = max8925_set_voltage,
 178         .get_voltage            = max8925_get_voltage,
 179         .enable                 = max8925_enable,
 180         .disable                = max8925_disable,
 181         .is_enabled             = max8925_is_enabled,
 182 };
 183
 184 #define MAX8925_SDV(_id, min, max, step)                        \
 185 {                                                               \
 186         .desc   = {                                             \
 187                 .name   = "SDV" #_id,                           \
 188                 .ops    = &max8925_regulator_sdv_ops,           \
 189                 .type   = REGULATOR_VOLTAGE,                    \
 190                 .id     = MAX8925_ID_SD##_id,                   \
 191                 .owner  = THIS_MODULE,                          \
 192         },                                                      \
 193         .min_uV         = min * 1000,                           \
 194         .max_uV         = max * 1000,                           \
 195         .step_uV        = step * 1000,                          \
 196         .vol_reg        = MAX8925_SDV##_id,                     \
 197         .vol_shift      = 0,                                    \
 198         .vol_nbits      = 6,                                    \
 199         .enable_reg     = MAX8925_SDCTL##_id,                   \
 200 }
 201
 202 #define MAX8925_LDO(_id, min, max, step)                        \
 203 {                                                               \
 204         .desc   = {                                             \
 205                 .name   = "LDO" #_id,                           \
 206                 .ops    = &max8925_regulator_ldo_ops,           \
 207                 .type   = REGULATOR_VOLTAGE,                    \
 208                 .id     = MAX8925_ID_LDO##_id,                  \
 209                 .owner  = THIS_MODULE,                          \
 210         },                                                      \
 211         .min_uV         = min * 1000,                           \
 212         .max_uV         = max * 1000,                           \
 213         .step_uV        = step * 1000,                          \
 214         .vol_reg        = MAX8925_LDOVOUT##_id,                 \
 215         .vol_shift      = 0,                                    \
 216         .vol_nbits      = 6,                                    \
 217         .enable_reg     = MAX8925_LDOCTL##_id,                  \
 218 }
 219
 220 static struct max8925_regulator_info max8925_regulator_info[] = {
 221         MAX8925_SDV(1, 637.5, 1425, 12.5),
 222         MAX8925_SDV(2,   650, 2225,   25),
 223         MAX8925_SDV(3,   750, 3900,   50),
 224
 225         MAX8925_LDO(1,  750, 3900, 50),
 226         MAX8925_LDO(2,  650, 2250, 25),
 227         MAX8925_LDO(3,  650, 2250, 25),
 228         MAX8925_LDO(4,  750, 3900, 50),
 229         MAX8925_LDO(5,  750, 3900, 50),
 230         MAX8925_LDO(6,  750, 3900, 50),
 231         MAX8925_LDO(7,  750, 3900, 50),
 232         MAX8925_LDO(8,  750, 3900, 50),
 233         MAX8925_LDO(9,  750, 3900, 50),
 234         MAX8925_LDO(10, 750, 3900, 50),
 235         MAX8925_LDO(11, 750, 3900, 50),
 236         MAX8925_LDO(12, 750, 3900, 50),
 237         MAX8925_LDO(13, 750, 3900, 50),
 238         MAX8925_LDO(14, 750, 3900, 50),
 239         MAX8925_LDO(15, 750, 3900, 50),
 240         MAX8925_LDO(16, 750, 3900, 50),
 241         MAX8925_LDO(17, 650, 2250, 25),
 242         MAX8925_LDO(18, 650, 2250, 25),
 243         MAX8925_LDO(19, 750, 3900, 50),
 244         MAX8925_LDO(20, 750, 3900, 50),
 245 };
 246
 247 static struct max8925_regulator_info * __devinit find_regulator_info(int id)
 248 {
 249         struct max8925_regulator_info *ri;
 250         int i;
 251
 252         for (i = 0; i < ARRAY_SIZE(max8925_regulator_info); i++) {
 253                 ri = &max8925_regulator_info[i];
 254                 if (ri->desc.id == id)
 255                         return ri;
 256         }
 257         return NULL;
 258 }
 259
 260 static int __devinit max8925_regulator_probe(struct platform_device *pdev)
 261 {
 262         struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
 263         struct max8925_platform_data *pdata = chip->dev->platform_data;
 264         struct max8925_regulator_info *ri;
 265         struct regulator_dev *rdev;
 266
 267         ri = find_regulator_info(pdev->id);
 268         if (ri == NULL) {
 269                 dev_err(&pdev->dev, "invalid regulator ID specified\n");
 270                 return -EINVAL;
 271         }
 272         ri->i2c = chip->i2c;
 273         ri->chip = chip;
 274
 275         rdev = regulator_register(&ri->desc, &pdev->dev,
 276                                   pdata->regulator[pdev->id], ri, NULL);
 277         if (IS_ERR(rdev)) {
 278                 dev_err(&pdev->dev, "failed to register regulator %s\n",
 279                                 ri->desc.name);
 280                 return PTR_ERR(rdev);
 281         }
 282
 283         platform_set_drvdata(pdev, rdev);
 284         return 0;
 285 }
 286
 287 static int __devexit max8925_regulator_remove(struct platform_device *pdev)
 288 {
 289         struct regulator_dev *rdev = platform_get_drvdata(pdev);
 290
 291         platform_set_drvdata(pdev, NULL);
 292         regulator_unregister(rdev);
 293
 294         return 0;
 295 }
 296
 297 static struct platform_driver max8925_regulator_driver = {
 298         .driver         = {
 299                 .name   = "max8925-regulator",
 300                 .owner  = THIS_MODULE,
 301         },
 302         .probe          = max8925_regulator_probe,
 303         .remove         = __devexit_p(max8925_regulator_remove),
 304 };
 305
 306 static int __init max8925_regulator_init(void)
 307 {
 308         return platform_driver_register(&max8925_regulator_driver);
 309 }
 310 subsys_initcall(max8925_regulator_init);
 311
 312 static void __exit max8925_regulator_exit(void)
 313 {
 314         platform_driver_unregister(&max8925_regulator_driver);
 315 }
 316 module_exit(max8925_regulator_exit);
 317
 318 MODULE_LICENSE("GPL");
 319 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
 320 MODULE_DESCRIPTION("Regulator Driver for Maxim 8925 PMIC");
 321 MODULE_ALIAS("platform:max8925-regulator");
 322