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 struct regulator_ops wm8994_ldo1_ops = {
  74         .enable = wm8994_ldo_enable,
  75         .disable = wm8994_ldo_disable,
  76         .is_enabled = wm8994_ldo_is_enabled,
  77
  78         .list_voltage = regulator_list_voltage_linear,
  79         .map_voltage = regulator_map_voltage_linear,
  80         .get_voltage_sel = regulator_get_voltage_sel_regmap,
  81         .set_voltage_sel = regulator_set_voltage_sel_regmap,
  82 };
  83
  84 static int wm8994_ldo2_list_voltage(struct regulator_dev *rdev,
  85                                     unsigned int selector)
  86 {
  87         struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
  88
  89         if (selector > WM8994_LDO2_MAX_SELECTOR)
  90                 return -EINVAL;
  91
  92         switch (ldo->wm8994->type) {
  93         case WM8994:
  94                 return (selector * 100000) + 900000;
  95         case WM8958:
  96                 return (selector * 100000) + 1000000;
  97         case WM1811:
  98                 switch (selector) {
  99                 case 0:
 100                         return -EINVAL;
 101                 default:
 102                         return (selector * 100000) + 950000;
 103                 }
 104                 break;
 105         default:
 106                 return -EINVAL;
 107         }
 108 }
 109
 110 static struct regulator_ops wm8994_ldo2_ops = {
 111         .enable = wm8994_ldo_enable,
 112         .disable = wm8994_ldo_disable,
 113         .is_enabled = wm8994_ldo_is_enabled,
 114
 115         .list_voltage = wm8994_ldo2_list_voltage,
 116         .get_voltage_sel = regulator_get_voltage_sel_regmap,
 117         .set_voltage_sel = regulator_set_voltage_sel_regmap,
 118 };
 119
 120 static const struct regulator_desc wm8994_ldo_desc[] = {
 121         {
 122                 .name = "LDO1",
 123                 .id = 1,
 124                 .type = REGULATOR_VOLTAGE,
 125                 .n_voltages = WM8994_LDO1_MAX_SELECTOR + 1,
 126                 .vsel_reg = WM8994_LDO_1,
 127                 .vsel_mask = WM8994_LDO1_VSEL_MASK,
 128                 .ops = &wm8994_ldo1_ops,
 129                 .min_uV = 2400000,
 130                 .uV_step = 100000,
 131                 .enable_time = 3000,
 132                 .owner = THIS_MODULE,
 133         },
 134         {
 135                 .name = "LDO2",
 136                 .id = 2,
 137                 .type = REGULATOR_VOLTAGE,
 138                 .n_voltages = WM8994_LDO2_MAX_SELECTOR + 1,
 139                 .vsel_reg = WM8994_LDO_2,
 140                 .vsel_mask = WM8994_LDO2_VSEL_MASK,
 141                 .ops = &wm8994_ldo2_ops,
 142                 .enable_time = 3000,
 143                 .owner = THIS_MODULE,
 144         },
 145 };
 146
 147 static __devinit int wm8994_ldo_probe(struct platform_device *pdev)
 148 {
 149         struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
 150         struct wm8994_pdata *pdata = wm8994->dev->platform_data;
 151         int id = pdev->id % ARRAY_SIZE(pdata->ldo);
 152         struct regulator_config config = { };
 153         struct wm8994_ldo *ldo;
 154         int ret;
 155
 156         dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1);
 157
 158         ldo = devm_kzalloc(&pdev->dev, sizeof(struct wm8994_ldo), GFP_KERNEL);
 159         if (ldo == NULL) {
 160                 dev_err(&pdev->dev, "Unable to allocate private data\n");
 161                 return -ENOMEM;
 162         }
 163
 164         ldo->wm8994 = wm8994;
 165
 166         if (pdata->ldo[id].enable && gpio_is_valid(pdata->ldo[id].enable)) {
 167                 ldo->enable = pdata->ldo[id].enable;
 168
 169                 ret = gpio_request_one(ldo->enable, 0, "WM8994 LDO enable");
 170                 if (ret < 0) {
 171                         dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n",
 172                                 ret);
 173                         goto err;
 174                 }
 175         } else
 176                 ldo->is_enabled = true;
 177
 178         config.dev = wm8994->dev;
 179         config.driver_data = ldo;
 180         config.regmap = wm8994->regmap;
 181         if (pdata)
 182                 config.init_data = pdata->ldo[id].init_data;
 183
 184         ldo->regulator = regulator_register(&wm8994_ldo_desc[id], &config);
 185         if (IS_ERR(ldo->regulator)) {
 186                 ret = PTR_ERR(ldo->regulator);
 187                 dev_err(wm8994->dev, "Failed to register LDO%d: %d\n",
 188                         id + 1, ret);
 189                 goto err_gpio;
 190         }
 191
 192         platform_set_drvdata(pdev, ldo);
 193
 194         return 0;
 195
 196 err_gpio:
 197         if (gpio_is_valid(ldo->enable))
 198                 gpio_free(ldo->enable);
 199 err:
 200         return ret;
 201 }
 202
 203 static __devexit int wm8994_ldo_remove(struct platform_device *pdev)
 204 {
 205         struct wm8994_ldo *ldo = platform_get_drvdata(pdev);
 206
 207         platform_set_drvdata(pdev, NULL);
 208
 209         regulator_unregister(ldo->regulator);
 210         if (gpio_is_valid(ldo->enable))
 211                 gpio_free(ldo->enable);
 212
 213         return 0;
 214 }
 215
 216 static struct platform_driver wm8994_ldo_driver = {
 217         .probe = wm8994_ldo_probe,
 218         .remove = __devexit_p(wm8994_ldo_remove),
 219         .driver         = {
 220                 .name   = "wm8994-ldo",
 221                 .owner  = THIS_MODULE,
 222         },
 223 };
 224
 225 static int __init wm8994_ldo_init(void)
 226 {
 227         int ret;
 228
 229         ret = platform_driver_register(&wm8994_ldo_driver);
 230         if (ret != 0)
 231                 pr_err("Failed to register Wm8994 GP LDO driver: %d\n", ret);
 232
 233         return ret;
 234 }
 235 subsys_initcall(wm8994_ldo_init);
 236
 237 static void __exit wm8994_ldo_exit(void)
 238 {
 239         platform_driver_unregister(&wm8994_ldo_driver);
 240 }
 241 module_exit(wm8994_ldo_exit);
 242
 243 /* Module information */
 244 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 245 MODULE_DESCRIPTION("WM8994 LDO driver");
 246 MODULE_LICENSE("GPL");
 247 MODULE_ALIAS("platform:wm8994-ldo");