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