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/mfd/syscon.h>
  25 #include <linux/err.h>
  26 #include <linux/io.h>
  27 #include <linux/platform_device.h>
  28 #include <linux/of.h>
  29 #include <linux/of_address.h>
  30 #include <linux/regmap.h>
  31 #include <linux/regulator/driver.h>
  32 #include <linux/regulator/of_regulator.h>
  33
  34 struct anatop_regulator {
  35         const char *name;
  36         u32 control_reg;
  37         struct regmap *anatop;
  38         int vol_bit_shift;
  39         int vol_bit_width;
  40         int min_bit_val;
  41         int min_voltage;
  42         int max_voltage;
  43         struct regulator_desc rdesc;
  44         struct regulator_init_data *initdata;
  45 };
  46
  47 static int anatop_regmap_set_voltage_sel(struct regulator_dev *reg,
  48                                         unsigned selector)
  49 {
  50         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
  51         u32 val, mask;
  52
  53         if (!anatop_reg->control_reg)
  54                 return -ENOTSUPP;
  55
  56         val = anatop_reg->min_bit_val + selector;
  57         dev_dbg(&reg->dev, "%s: calculated val %d\n", __func__, val);
  58         mask = ((1 << anatop_reg->vol_bit_width) - 1) <<
  59                 anatop_reg->vol_bit_shift;
  60         val <<= anatop_reg->vol_bit_shift;
  61         regmap_update_bits(anatop_reg->anatop, anatop_reg->control_reg,
  62                                 mask, val);
  63
  64         return 0;
  65 }
  66
  67 static int anatop_regmap_get_voltage_sel(struct regulator_dev *reg)
  68 {
  69         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
  70         u32 val, mask;
  71
  72         if (!anatop_reg->control_reg)
  73                 return -ENOTSUPP;
  74
  75         regmap_read(anatop_reg->anatop, anatop_reg->control_reg, &val);
  76         mask = ((1 << anatop_reg->vol_bit_width) - 1) <<
  77                 anatop_reg->vol_bit_shift;
  78         val = (val & mask) >> anatop_reg->vol_bit_shift;
  79
  80         return val - anatop_reg->min_bit_val;
  81 }
  82
  83 static struct regulator_ops anatop_rops = {
  84         .set_voltage_sel = anatop_regmap_set_voltage_sel,
  85         .get_voltage_sel = anatop_regmap_get_voltage_sel,
  86         .list_voltage = regulator_list_voltage_linear,
  87         .map_voltage = regulator_map_voltage_linear,
  88 };
  89
  90 static int anatop_regulator_probe(struct platform_device *pdev)
  91 {
  92         struct device *dev = &pdev->dev;
  93         struct device_node *np = dev->of_node;
  94         struct device_node *anatop_np;
  95         struct regulator_desc *rdesc;
  96         struct regulator_dev *rdev;
  97         struct anatop_regulator *sreg;
  98         struct regulator_init_data *initdata;
  99         struct regulator_config config = { };
 100         int ret = 0;
 101
 102         initdata = of_get_regulator_init_data(dev, np);
 103         sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL);
 104         if (!sreg)
 105                 return -ENOMEM;
 106         sreg->initdata = initdata;
 107         sreg->name = kstrdup(of_get_property(np, "regulator-name", NULL),
 108                              GFP_KERNEL);
 109         rdesc = &sreg->rdesc;
 110         memset(rdesc, 0, sizeof(*rdesc));
 111         rdesc->name = sreg->name;
 112         rdesc->ops = &anatop_rops;
 113         rdesc->type = REGULATOR_VOLTAGE;
 114         rdesc->owner = THIS_MODULE;
 115
 116         anatop_np = of_get_parent(np);
 117         if (!anatop_np)
 118                 return -ENODEV;
 119         sreg->anatop = syscon_node_to_regmap(anatop_np);
 120         of_node_put(anatop_np);
 121         if (IS_ERR(sreg->anatop))
 122                 return PTR_ERR(sreg->anatop);
 123
 124         ret = of_property_read_u32(np, "anatop-reg-offset",
 125                                    &sreg->control_reg);
 126         if (ret) {
 127                 dev_err(dev, "no anatop-reg-offset property set\n");
 128                 goto anatop_probe_end;
 129         }
 130         ret = of_property_read_u32(np, "anatop-vol-bit-width",
 131                                    &sreg->vol_bit_width);
 132         if (ret) {
 133                 dev_err(dev, "no anatop-vol-bit-width property set\n");
 134                 goto anatop_probe_end;
 135         }
 136         ret = of_property_read_u32(np, "anatop-vol-bit-shift",
 137                                    &sreg->vol_bit_shift);
 138         if (ret) {
 139                 dev_err(dev, "no anatop-vol-bit-shift property set\n");
 140                 goto anatop_probe_end;
 141         }
 142         ret = of_property_read_u32(np, "anatop-min-bit-val",
 143                                    &sreg->min_bit_val);
 144         if (ret) {
 145                 dev_err(dev, "no anatop-min-bit-val property set\n");
 146                 goto anatop_probe_end;
 147         }
 148         ret = of_property_read_u32(np, "anatop-min-voltage",
 149                                    &sreg->min_voltage);
 150         if (ret) {
 151                 dev_err(dev, "no anatop-min-voltage property set\n");
 152                 goto anatop_probe_end;
 153         }
 154         ret = of_property_read_u32(np, "anatop-max-voltage",
 155                                    &sreg->max_voltage);
 156         if (ret) {
 157                 dev_err(dev, "no anatop-max-voltage property set\n");
 158                 goto anatop_probe_end;
 159         }
 160
 161         rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage)
 162                 / 25000 + 1;
 163         rdesc->min_uV = sreg->min_voltage;
 164         rdesc->uV_step = 25000;
 165
 166         config.dev = &pdev->dev;
 167         config.init_data = initdata;
 168         config.driver_data = sreg;
 169         config.of_node = pdev->dev.of_node;
 170
 171         /* register regulator */
 172         rdev = regulator_register(rdesc, &config);
 173         if (IS_ERR(rdev)) {
 174                 dev_err(dev, "failed to register %s\n",
 175                         rdesc->name);
 176                 ret = PTR_ERR(rdev);
 177                 goto anatop_probe_end;
 178         }
 179
 180         platform_set_drvdata(pdev, rdev);
 181
 182 anatop_probe_end:
 183         if (ret)
 184                 kfree(sreg->name);
 185
 186         return ret;
 187 }
 188
 189 static int anatop_regulator_remove(struct platform_device *pdev)
 190 {
 191         struct regulator_dev *rdev = platform_get_drvdata(pdev);
 192         struct anatop_regulator *sreg = rdev_get_drvdata(rdev);
 193         const char *name = sreg->name;
 194
 195         regulator_unregister(rdev);
 196         kfree(name);
 197
 198         return 0;
 199 }
 200
 201 static struct of_device_id __devinitdata of_anatop_regulator_match_tbl[] = {
 202         { .compatible = "fsl,anatop-regulator", },
 203         { /* end */ }
 204 };
 205
 206 static struct platform_driver anatop_regulator_driver = {
 207         .driver = {
 208                 .name   = "anatop_regulator",
 209                 .owner  = THIS_MODULE,
 210                 .of_match_table = of_anatop_regulator_match_tbl,
 211         },
 212         .probe  = anatop_regulator_probe,
 213         .remove = anatop_regulator_remove,
 214 };
 215
 216 static int __init anatop_regulator_init(void)
 217 {
 218         return platform_driver_register(&anatop_regulator_driver);
 219 }
 220 postcore_initcall(anatop_regulator_init);
 221
 222 static void __exit anatop_regulator_exit(void)
 223 {
 224         platform_driver_unregister(&anatop_regulator_driver);
 225 }
 226 module_exit(anatop_regulator_exit);
 227
 228 MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>, "
 229               "Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>");
 230 MODULE_DESCRIPTION("ANATOP Regulator driver");
 231 MODULE_LICENSE("GPL v2");