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;
  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         anatop_set_bits(anatop_reg->mfd,
  75                         anatop_reg->control_reg,
  76                         anatop_reg->vol_bit_shift,
  77                         anatop_reg->vol_bit_width,
  78                         val);
  79
  80         return 0;
  81 }
  82
  83 static int anatop_get_voltage_sel(struct regulator_dev *reg)
  84 {
  85         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
  86         u32 val;
  87
  88         if (!anatop_reg->control_reg)
  89                 return -ENOTSUPP;
  90
  91         val = anatop_get_bits(anatop_reg->mfd,
  92                               anatop_reg->control_reg,
  93                               anatop_reg->vol_bit_shift,
  94                               anatop_reg->vol_bit_width);
  95
  96         return val - anatop_reg->min_bit_val;
  97 }
  98
  99 static int anatop_list_voltage(struct regulator_dev *reg, unsigned selector)
 100 {
 101         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
 102         int uv;
 103
 104         uv = anatop_reg->min_voltage + selector * 25000;
 105         dev_dbg(&reg->dev, "vddio = %d, selector = %u\n", uv, selector);
 106
 107         return uv;
 108 }
 109
 110 static struct regulator_ops anatop_rops = {
 111         .set_voltage     = anatop_set_voltage,
 112         .get_voltage_sel = anatop_get_voltage_sel,
 113         .list_voltage    = anatop_list_voltage,
 114 };
 115
 116 static int __devinit anatop_regulator_probe(struct platform_device *pdev)
 117 {
 118         struct device *dev = &pdev->dev;
 119         struct device_node *np = dev->of_node;
 120         struct regulator_desc *rdesc;
 121         struct regulator_dev *rdev;
 122         struct anatop_regulator *sreg;
 123         struct regulator_init_data *initdata;
 124         struct anatop *anatopmfd = dev_get_drvdata(pdev->dev.parent);
 125         int ret = 0;
 126
 127         initdata = of_get_regulator_init_data(dev, np);
 128         sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL);
 129         if (!sreg)
 130                 return -ENOMEM;
 131         sreg->initdata = initdata;
 132         sreg->name = kstrdup(of_get_property(np, "regulator-name", NULL),
 133                              GFP_KERNEL);
 134         rdesc = &sreg->rdesc;
 135         memset(rdesc, 0, sizeof(*rdesc));
 136         rdesc->name = sreg->name;
 137         rdesc->ops = &anatop_rops;
 138         rdesc->type = REGULATOR_VOLTAGE;
 139         rdesc->owner = THIS_MODULE;
 140         sreg->mfd = anatopmfd;
 141         ret = of_property_read_u32(np, "anatop-reg-offset",
 142                                    &sreg->control_reg);
 143         if (ret) {
 144                 dev_err(dev, "no anatop-reg-offset property set\n");
 145                 goto anatop_probe_end;
 146         }
 147         ret = of_property_read_u32(np, "anatop-vol-bit-width",
 148                                    &sreg->vol_bit_width);
 149         if (ret) {
 150                 dev_err(dev, "no anatop-vol-bit-width property set\n");
 151                 goto anatop_probe_end;
 152         }
 153         ret = of_property_read_u32(np, "anatop-vol-bit-shift",
 154                                    &sreg->vol_bit_shift);
 155         if (ret) {
 156                 dev_err(dev, "no anatop-vol-bit-shift property set\n");
 157                 goto anatop_probe_end;
 158         }
 159         ret = of_property_read_u32(np, "anatop-min-bit-val",
 160                                    &sreg->min_bit_val);
 161         if (ret) {
 162                 dev_err(dev, "no anatop-min-bit-val property set\n");
 163                 goto anatop_probe_end;
 164         }
 165         ret = of_property_read_u32(np, "anatop-min-voltage",
 166                                    &sreg->min_voltage);
 167         if (ret) {
 168                 dev_err(dev, "no anatop-min-voltage property set\n");
 169                 goto anatop_probe_end;
 170         }
 171         ret = of_property_read_u32(np, "anatop-max-voltage",
 172                                    &sreg->max_voltage);
 173         if (ret) {
 174                 dev_err(dev, "no anatop-max-voltage property set\n");
 175                 goto anatop_probe_end;
 176         }
 177
 178         rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage)
 179                 / 25000 + 1;
 180
 181         /* register regulator */
 182         rdev = regulator_register(rdesc, dev,
 183                                   initdata, sreg, pdev->dev.of_node);
 184         if (IS_ERR(rdev)) {
 185                 dev_err(dev, "failed to register %s\n",
 186                         rdesc->name);
 187                 ret = PTR_ERR(rdev);
 188                 goto anatop_probe_end;
 189         }
 190
 191         platform_set_drvdata(pdev, rdev);
 192
 193 anatop_probe_end:
 194         if (ret)
 195                 kfree(sreg->name);
 196
 197         return ret;
 198 }
 199
 200 static int __devexit anatop_regulator_remove(struct platform_device *pdev)
 201 {
 202         struct regulator_dev *rdev = platform_get_drvdata(pdev);
 203         struct anatop_regulator *sreg = rdev_get_drvdata(rdev);
 204         const char *name = sreg->name;
 205
 206         regulator_unregister(rdev);
 207         kfree(name);
 208
 209         return 0;
 210 }
 211
 212 static struct of_device_id __devinitdata of_anatop_regulator_match_tbl[] = {
 213         { .compatible = "fsl,anatop-regulator", },
 214         { /* end */ }
 215 };
 216
 217 static struct platform_driver anatop_regulator_driver = {
 218         .driver = {
 219                 .name   = "anatop_regulator",
 220                 .owner  = THIS_MODULE,
 221                 .of_match_table = of_anatop_regulator_match_tbl,
 222         },
 223         .probe  = anatop_regulator_probe,
 224         .remove = anatop_regulator_remove,
 225 };
 226
 227 static int __init anatop_regulator_init(void)
 228 {
 229         return platform_driver_register(&anatop_regulator_driver);
 230 }
 231 postcore_initcall(anatop_regulator_init);
 232
 233 static void __exit anatop_regulator_exit(void)
 234 {
 235         platform_driver_unregister(&anatop_regulator_driver);
 236 }
 237 module_exit(anatop_regulator_exit);
 238
 239 MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>, "
 240               "Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>");
 241 MODULE_DESCRIPTION("ANATOP Regulator driver");
 242 MODULE_LICENSE("GPL v2");