drivers/regulator/wm8994-regulator.c

   1 /*
   2  * wm8994-regulator.c  --  Regulator driver for the WM8994
   3  *
   4  * Copyright 2009 Wolfson Microelectronics PLC.
   5  *
   6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7  *
   8  *  This program is free software; you can redistribute  it and/or modify it
   9  *  under  the terms of  the GNU General  Public License as published by the
  10  *  Free Software Foundation;  either version 2 of the  License, or (at your
  11  *  option) any later version.
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/moduleparam.h>
  16 #include <linux/init.h>
  17 #include <linux/bitops.h>
  18 #include <linux/err.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/regulator/driver.h>
  21 #include <linux/gpio.h>
  22 #include <linux/slab.h>
  23
  24 #include <linux/mfd/wm8994/core.h>
  25 #include <linux/mfd/wm8994/registers.h>
  26 #include <linux/mfd/wm8994/pdata.h>
  27
  28 struct wm8994_ldo {
  29         int enable;
  30         bool is_enabled;
  31         struct regulator_dev *regulator;
  32         struct wm8994 *wm8994;
  33 };
  34
  35 #define WM8994_LDO1_MAX_SELECTOR 0x7
  36 #define WM8994_LDO2_MAX_SELECTOR 0x3
  37
  38 static int wm8994_ldo_enable(struct regulator_dev *rdev)
  39 {
  40         struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
  41
  42         /* If we have no soft control assume that the LDO is always enabled. */
  43         if (!ldo->enable)
  44                 return 0;
  45
  46         gpio_set_value_cansleep(ldo->enable, 1);
  47         ldo->is_enabled = true;
  48
  49         return 0;
  50 }
  51
  52 static int wm8994_ldo_disable(struct regulator_dev *rdev)
  53 {
  54         struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
  55
  56         /* If we have no soft control assume that the LDO is always enabled. */
  57         if (!ldo->enable)
  58                 return -EINVAL;
  59
  60         gpio_set_value_cansleep(ldo->enable, 0);
  61         ldo->is_enabled = false;
  62
  63         return 0;
  64 }
  65
  66 static int wm8994_ldo_is_enabled(struct regulator_dev *rdev)
  67 {
  68         struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
  69
  70         return ldo->is_enabled;
  71 }
  72
  73 static int wm8994_ldo_enable_time(struct regulator_dev *rdev)
  74 {
  75         /* 3ms is fairly conservative but this shouldn't be too performance
  76          * critical; can be tweaked per-system if required. */
  77         return 3000;
  78 }
  79
  80 static int wm8994_ldo1_list_voltage(struct regulator_dev *rdev,
  81                                     unsigned int selector)
  82 {
  83         if (selector > WM8994_LDO1_MAX_SELECTOR)
  84                 return -EINVAL;
  85
  86         return (selector * 100000) + 2400000;
  87 }
  88
  89 static int wm8994_ldo1_get_voltage_sel(struct regulator_dev *rdev)
  90 {
  91         struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
  92         int val;
  93
  94         val = wm8994_reg_read(ldo->wm8994, WM8994_LDO_1);
  95         if (val < 0)
  96                 return val;
  97
  98         return (val & WM8994_LDO1_VSEL_MASK) >> WM8994_LDO1_VSEL_SHIFT;
  99 }
 100
 101 static int wm8994_ldo1_set_voltage_sel(struct regulator_dev *rdev,
 102                                        unsigned selector)
 103 {
 104         struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
 105
 106         selector <<= WM8994_LDO1_VSEL_SHIFT;
 107
 108         return wm8994_set_bits(ldo->wm8994, WM8994_LDO_1,
 109                                WM8994_LDO1_VSEL_MASK, selector);
 110 }
 111
 112 static struct regulator_ops wm8994_ldo1_ops = {
 113         .enable = wm8994_ldo_enable,
 114         .disable = wm8994_ldo_disable,
 115         .is_enabled = wm8994_ldo_is_enabled,
 116         .enable_time = wm8994_ldo_enable_time,
 117
 118         .list_voltage = wm8994_ldo1_list_voltage,
 119         .get_voltage_sel = wm8994_ldo1_get_voltage_sel,
 120         .set_voltage_sel = wm8994_ldo1_set_voltage_sel,
 121 };
 122
 123 static int wm8994_ldo2_list_voltage(struct regulator_dev *rdev,
 124                                     unsigned int selector)
 125 {
 126         struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
 127
 128         if (selector > WM8994_LDO2_MAX_SELECTOR)
 129                 return -EINVAL;
 130
 131         switch (ldo->wm8994->type) {
 132         case WM8994:
 133                 return (selector * 100000) + 900000;
 134         case WM8958:
 135                 return (selector * 100000) + 1000000;
 136         case WM1811:
 137                 switch (selector) {
 138                 case 0:
 139                         return -EINVAL;
 140                 default:
 141                         return (selector * 100000) + 950000;
 142                 }
 143                 break;
 144         default:
 145                 return -EINVAL;
 146         }
 147 }
 148
 149 static int wm8994_ldo2_get_voltage_sel(struct regulator_dev *rdev)
 150 {
 151         struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
 152         int val;
 153
 154         val = wm8994_reg_read(ldo->wm8994, WM8994_LDO_2);
 155         if (val < 0)
 156                 return val;
 157
 158         return (val & WM8994_LDO2_VSEL_MASK) >> WM8994_LDO2_VSEL_SHIFT;
 159 }
 160
 161 static int wm8994_ldo2_set_voltage_sel(struct regulator_dev *rdev,
 162                                        unsigned selector)
 163 {
 164         struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
 165
 166         selector <<= WM8994_LDO2_VSEL_SHIFT;
 167
 168         return wm8994_set_bits(ldo->wm8994, WM8994_LDO_2,
 169                                WM8994_LDO2_VSEL_MASK, selector);
 170 }
 171
 172 static struct regulator_ops wm8994_ldo2_ops = {
 173         .enable = wm8994_ldo_enable,
 174         .disable = wm8994_ldo_disable,
 175         .is_enabled = wm8994_ldo_is_enabled,
 176         .enable_time = wm8994_ldo_enable_time,
 177
 178         .list_voltage = wm8994_ldo2_list_voltage,
 179         .get_voltage_sel = wm8994_ldo2_get_voltage_sel,
 180         .set_voltage_sel = wm8994_ldo2_set_voltage_sel,
 181 };
 182
 183 static const struct regulator_desc wm8994_ldo_desc[] = {
 184         {
 185                 .name = "LDO1",
 186                 .id = 1,
 187                 .type = REGULATOR_VOLTAGE,
 188                 .n_voltages = WM8994_LDO1_MAX_SELECTOR + 1,
 189                 .ops = &wm8994_ldo1_ops,
 190                 .owner = THIS_MODULE,
 191         },
 192         {
 193                 .name = "LDO2",
 194                 .id = 2,
 195                 .type = REGULATOR_VOLTAGE,
 196                 .n_voltages = WM8994_LDO2_MAX_SELECTOR + 1,
 197                 .ops = &wm8994_ldo2_ops,
 198                 .owner = THIS_MODULE,
 199         },
 200 };
 201
 202 static __devinit int wm8994_ldo_probe(struct platform_device *pdev)
 203 {
 204         struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
 205         struct wm8994_pdata *pdata = wm8994->dev->platform_data;
 206         int id = pdev->id % ARRAY_SIZE(pdata->ldo);
 207         struct regulator_config config = { };
 208         struct wm8994_ldo *ldo;
 209         int ret;
 210
 211         dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1);
 212
 213         if (!pdata)
 214                 return -ENODEV;
 215
 216         ldo = devm_kzalloc(&pdev->dev, sizeof(struct wm8994_ldo), GFP_KERNEL);
 217         if (ldo == NULL) {
 218                 dev_err(&pdev->dev, "Unable to allocate private data\n");
 219                 return -ENOMEM;
 220         }
 221
 222         ldo->wm8994 = wm8994;
 223
 224         if (pdata->ldo[id].enable && gpio_is_valid(pdata->ldo[id].enable)) {
 225                 ldo->enable = pdata->ldo[id].enable;
 226
 227                 ret = gpio_request_one(ldo->enable, 0, "WM8994 LDO enable");
 228                 if (ret < 0) {
 229                         dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n",
 230                                 ret);
 231                         goto err;
 232                 }
 233         } else
 234                 ldo->is_enabled = true;
 235
 236         config.dev = wm8994->dev;
 237         config.init_data = pdata->ldo[id].init_data;
 238         config.driver_data = ldo;
 239
 240         ldo->regulator = regulator_register(&wm8994_ldo_desc[id], &config);
 241         if (IS_ERR(ldo->regulator)) {
 242                 ret = PTR_ERR(ldo->regulator);
 243                 dev_err(wm8994->dev, "Failed to register LDO%d: %d\n",
 244                         id + 1, ret);
 245                 goto err_gpio;
 246         }
 247
 248         platform_set_drvdata(pdev, ldo);
 249
 250         return 0;
 251
 252 err_gpio:
 253         if (gpio_is_valid(ldo->enable))
 254                 gpio_free(ldo->enable);
 255 err:
 256         return ret;
 257 }
 258
 259 static __devexit int wm8994_ldo_remove(struct platform_device *pdev)
 260 {
 261         struct wm8994_ldo *ldo = platform_get_drvdata(pdev);
 262
 263         platform_set_drvdata(pdev, NULL);
 264
 265         regulator_unregister(ldo->regulator);
 266         if (gpio_is_valid(ldo->enable))
 267                 gpio_free(ldo->enable);
 268
 269         return 0;
 270 }
 271
 272 static struct platform_driver wm8994_ldo_driver = {
 273         .probe = wm8994_ldo_probe,
 274         .remove = __devexit_p(wm8994_ldo_remove),
 275         .driver         = {
 276                 .name   = "wm8994-ldo",
 277                 .owner  = THIS_MODULE,
 278         },
 279 };
 280
 281 static int __init wm8994_ldo_init(void)
 282 {
 283         int ret;
 284
 285         ret = platform_driver_register(&wm8994_ldo_driver);
 286         if (ret != 0)
 287                 pr_err("Failed to register Wm8994 GP LDO driver: %d\n", ret);
 288
 289         return ret;
 290 }
 291 subsys_initcall(wm8994_ldo_init);
 292
 293 static void __exit wm8994_ldo_exit(void)
 294 {
 295         platform_driver_unregister(&wm8994_ldo_driver);
 296 }
 297 module_exit(wm8994_ldo_exit);
 298
 299 /* Module information */
 300 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 301 MODULE_DESCRIPTION("WM8994 LDO driver");
 302 MODULE_LICENSE("GPL");
 303 MODULE_ALIAS("platform:wm8994-ldo");