drivers/regulator/anatop-regulator.c

   1 /*
   2  * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
   3  */
   4
   5 /*
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #include <linux/slab.h>
  22 #include <linux/device.h>
  23 #include <linux/module.h>
  24 #include <linux/err.h>
  25 #include <linux/io.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/of.h>
  28 #include <linux/of_address.h>
  29 #include <linux/mfd/anatop.h>
  30 #include <linux/regulator/driver.h>
  31 #include <linux/regulator/of_regulator.h>
  32
  33 struct anatop_regulator {
  34         const char *name;
  35         u32 control_reg;
  36         struct anatop *mfd;
  37         int vol_bit_shift;
  38         int vol_bit_width;
  39         int min_bit_val;
  40         int min_voltage;
  41         int max_voltage;
  42         struct regulator_desc rdesc;
  43         struct regulator_init_data *initdata;
  44 };
  45
  46 static int anatop_set_voltage(struct regulator_dev *reg, int min_uV,
  47                                   int max_uV, unsigned *selector)
  48 {
  49         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
  50         u32 val, sel, mask;
  51         int uv;
  52
  53         uv = min_uV;
  54         dev_dbg(&reg->dev, "%s: uv %d, min %d, max %d\n", __func__,
  55                 uv, anatop_reg->min_voltage,
  56                 anatop_reg->max_voltage);
  57
  58         if (uv < anatop_reg->min_voltage) {
  59                 if (max_uV > anatop_reg->min_voltage)
  60                         uv = anatop_reg->min_voltage;
  61                 else
  62                         return -EINVAL;
  63         }
  64
  65         if (!anatop_reg->control_reg)
  66                 return -ENOTSUPP;
  67
  68         sel = DIV_ROUND_UP(uv - anatop_reg->min_voltage, 25000);
  69         if (sel * 25000 + anatop_reg->min_voltage > anatop_reg->max_voltage)
  70                 return -EINVAL;
  71         val = anatop_reg->min_bit_val + sel;
  72         *selector = sel;
  73         dev_dbg(&reg->dev, "%s: calculated val %d\n", __func__, val);
  74         mask = ((1 << anatop_reg->vol_bit_width) - 1) <<
  75                 anatop_reg->vol_bit_shift;
  76         val <<= anatop_reg->vol_bit_shift;
  77         anatop_write_reg(anatop_reg->mfd, anatop_reg->control_reg, val, mask);
  78
  79         return 0;
  80 }
  81
  82 static int anatop_get_voltage_sel(struct regulator_dev *reg)
  83 {
  84         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
  85         u32 val;
  86
  87         if (!anatop_reg->control_reg)
  88                 return -ENOTSUPP;
  89
  90         val = anatop_read_reg(anatop_reg->mfd, anatop_reg->control_reg);
  91         val = (val & ((1 << anatop_reg->vol_bit_width) - 1)) >>
  92                 anatop_reg->vol_bit_shift;
  93
  94         return val - anatop_reg->min_bit_val;
  95 }
  96
  97 static int anatop_list_voltage(struct regulator_dev *reg, unsigned selector)
  98 {
  99         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
 100         int uv;
 101
 102         uv = anatop_reg->min_voltage + selector * 25000;
 103         dev_dbg(&reg->dev, "vddio = %d, selector = %u\n", uv, selector);
 104
 105         return uv;
 106 }
 107
 108 static struct regulator_ops anatop_rops = {
 109         .set_voltage     = anatop_set_voltage,
 110         .get_voltage_sel = anatop_get_voltage_sel,
 111         .list_voltage    = anatop_list_voltage,
 112 };
 113
 114 static int __devinit anatop_regulator_probe(struct platform_device *pdev)
 115 {
 116         struct device *dev = &pdev->dev;
 117         struct device_node *np = dev->of_node;
 118         struct regulator_desc *rdesc;
 119         struct regulator_dev *rdev;
 120         struct anatop_regulator *sreg;
 121         struct regulator_init_data *initdata;
 122         struct anatop *anatopmfd = dev_get_drvdata(pdev->dev.parent);
 123         struct regulator_config config = { };
 124         int ret = 0;
 125
 126         initdata = of_get_regulator_init_data(dev, np);
 127         sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL);
 128         if (!sreg)
 129                 return -ENOMEM;
 130         sreg->initdata = initdata;
 131         sreg->name = kstrdup(of_get_property(np, "regulator-name", NULL),
 132                              GFP_KERNEL);
 133         rdesc = &sreg->rdesc;
 134         memset(rdesc, 0, sizeof(*rdesc));
 135         rdesc->name = sreg->name;
 136         rdesc->ops = &anatop_rops;
 137         rdesc->type = REGULATOR_VOLTAGE;
 138         rdesc->owner = THIS_MODULE;
 139         sreg->mfd = anatopmfd;
 140         ret = of_property_read_u32(np, "anatop-reg-offset",
 141                                    &sreg->control_reg);
 142         if (ret) {
 143                 dev_err(dev, "no anatop-reg-offset property set\n");
 144                 goto anatop_probe_end;
 145         }
 146         ret = of_property_read_u32(np, "anatop-vol-bit-width",
 147                                    &sreg->vol_bit_width);
 148         if (ret) {
 149                 dev_err(dev, "no anatop-vol-bit-width property set\n");
 150                 goto anatop_probe_end;
 151         }
 152         ret = of_property_read_u32(np, "anatop-vol-bit-shift",
 153                                    &sreg->vol_bit_shift);
 154         if (ret) {
 155                 dev_err(dev, "no anatop-vol-bit-shift property set\n");
 156                 goto anatop_probe_end;
 157         }
 158         ret = of_property_read_u32(np, "anatop-min-bit-val",
 159                                    &sreg->min_bit_val);
 160         if (ret) {
 161                 dev_err(dev, "no anatop-min-bit-val property set\n");
 162                 goto anatop_probe_end;
 163         }
 164         ret = of_property_read_u32(np, "anatop-min-voltage",
 165                                    &sreg->min_voltage);
 166         if (ret) {
 167                 dev_err(dev, "no anatop-min-voltage property set\n");
 168                 goto anatop_probe_end;
 169         }
 170         ret = of_property_read_u32(np, "anatop-max-voltage",
 171                                    &sreg->max_voltage);
 172         if (ret) {
 173                 dev_err(dev, "no anatop-max-voltage property set\n");
 174                 goto anatop_probe_end;
 175         }
 176
 177         rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage)
 178                 / 25000 + 1;
 179
 180         config.dev = &pdev->dev;
 181         config.init_data = initdata;
 182         config.driver_data = sreg;
 183         config.of_node = pdev->dev.of_node;
 184
 185         /* register regulator */
 186         rdev = regulator_register(rdesc, &config);
 187         if (IS_ERR(rdev)) {
 188                 dev_err(dev, "failed to register %s\n",
 189                         rdesc->name);
 190                 ret = PTR_ERR(rdev);
 191                 goto anatop_probe_end;
 192         }
 193
 194         platform_set_drvdata(pdev, rdev);
 195
 196 anatop_probe_end:
 197         if (ret)
 198                 kfree(sreg->name);
 199
 200         return ret;
 201 }
 202
 203 static int __devexit anatop_regulator_remove(struct platform_device *pdev)
 204 {
 205         struct regulator_dev *rdev = platform_get_drvdata(pdev);
 206         struct anatop_regulator *sreg = rdev_get_drvdata(rdev);
 207         const char *name = sreg->name;
 208
 209         regulator_unregister(rdev);
 210         kfree(name);
 211
 212         return 0;
 213 }
 214
 215 static struct of_device_id __devinitdata of_anatop_regulator_match_tbl[] = {
 216         { .compatible = "fsl,anatop-regulator", },
 217         { /* end */ }
 218 };
 219
 220 static struct platform_driver anatop_regulator_driver = {
 221         .driver = {
 222                 .name   = "anatop_regulator",
 223                 .owner  = THIS_MODULE,
 224                 .of_match_table = of_anatop_regulator_match_tbl,
 225         },
 226         .probe  = anatop_regulator_probe,
 227         .remove = anatop_regulator_remove,
 228 };
 229
 230 static int __init anatop_regulator_init(void)
 231 {
 232         return platform_driver_register(&anatop_regulator_driver);
 233 }
 234 postcore_initcall(anatop_regulator_init);
 235
 236 static void __exit anatop_regulator_exit(void)
 237 {
 238         platform_driver_unregister(&anatop_regulator_driver);
 239 }
 240 module_exit(anatop_regulator_exit);
 241
 242 MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>, "
 243               "Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>");
 244 MODULE_DESCRIPTION("ANATOP Regulator driver");
 245 MODULE_LICENSE("GPL v2");