drivers/regulator/anatop-regulator.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
   4
   5 #include <linux/slab.h>
   6 #include <linux/device.h>
   7 #include <linux/module.h>
   8 #include <linux/mfd/syscon.h>
   9 #include <linux/err.h>
  10 #include <linux/io.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/of.h>
  13 #include <linux/of_address.h>
  14 #include <linux/regmap.h>
  15 #include <linux/regulator/driver.h>
  16 #include <linux/regulator/of_regulator.h>
  17 #include <linux/regulator/machine.h>
  18
  19 #define LDO_RAMP_UP_UNIT_IN_CYCLES      64 /* 64 cycles per step */
  20 #define LDO_RAMP_UP_FREQ_IN_MHZ         24 /* cycle based on 24M OSC */
  21
  22 #define LDO_POWER_GATE                  0x00
  23 #define LDO_FET_FULL_ON                 0x1f
  24
  25 struct anatop_regulator {
  26         u32 control_reg;
  27         struct regmap *anatop;
  28         int vol_bit_shift;
  29         int vol_bit_width;
  30         u32 delay_reg;
  31         int delay_bit_shift;
  32         int delay_bit_width;
  33         int min_bit_val;
  34         int min_voltage;
  35         int max_voltage;
  36         struct regulator_desc rdesc;
  37         struct regulator_init_data *initdata;
  38         bool bypass;
  39         int sel;
  40 };
  41
  42 static int anatop_regmap_set_voltage_time_sel(struct regulator_dev *reg,
  43         unsigned int old_sel,
  44         unsigned int new_sel)
  45 {
  46         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
  47         u32 val;
  48         int ret = 0;
  49
  50         /* check whether need to care about LDO ramp up speed */
  51         if (anatop_reg->delay_bit_width && new_sel > old_sel) {
  52                 /*
  53                  * the delay for LDO ramp up time is
  54                  * based on the register setting, we need
  55                  * to calculate how many steps LDO need to
  56                  * ramp up, and how much delay needed. (us)
  57                  */
  58                 regmap_read(anatop_reg->anatop, anatop_reg->delay_reg, &val);
  59                 val = (val >> anatop_reg->delay_bit_shift) &
  60                         ((1 << anatop_reg->delay_bit_width) - 1);
  61                 ret = (new_sel - old_sel) * (LDO_RAMP_UP_UNIT_IN_CYCLES <<
  62                         val) / LDO_RAMP_UP_FREQ_IN_MHZ + 1;
  63         }
  64
  65         return ret;
  66 }
  67
  68 static int anatop_regmap_enable(struct regulator_dev *reg)
  69 {
  70         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
  71         int sel;
  72
  73         sel = anatop_reg->bypass ? LDO_FET_FULL_ON : anatop_reg->sel;
  74         return regulator_set_voltage_sel_regmap(reg, sel);
  75 }
  76
  77 static int anatop_regmap_disable(struct regulator_dev *reg)
  78 {
  79         return regulator_set_voltage_sel_regmap(reg, LDO_POWER_GATE);
  80 }
  81
  82 static int anatop_regmap_is_enabled(struct regulator_dev *reg)
  83 {
  84         return regulator_get_voltage_sel_regmap(reg) != LDO_POWER_GATE;
  85 }
  86
  87 static int anatop_regmap_core_set_voltage_sel(struct regulator_dev *reg,
  88                                               unsigned selector)
  89 {
  90         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
  91         int ret;
  92
  93         if (anatop_reg->bypass || !anatop_regmap_is_enabled(reg)) {
  94                 anatop_reg->sel = selector;
  95                 return 0;
  96         }
  97
  98         ret = regulator_set_voltage_sel_regmap(reg, selector);
  99         if (!ret)
 100                 anatop_reg->sel = selector;
 101         return ret;
 102 }
 103
 104 static int anatop_regmap_core_get_voltage_sel(struct regulator_dev *reg)
 105 {
 106         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
 107
 108         if (anatop_reg->bypass || !anatop_regmap_is_enabled(reg))
 109                 return anatop_reg->sel;
 110
 111         return regulator_get_voltage_sel_regmap(reg);
 112 }
 113
 114 static int anatop_regmap_get_bypass(struct regulator_dev *reg, bool *enable)
 115 {
 116         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
 117         int sel;
 118
 119         sel = regulator_get_voltage_sel_regmap(reg);
 120         if (sel == LDO_FET_FULL_ON)
 121                 WARN_ON(!anatop_reg->bypass);
 122         else if (sel != LDO_POWER_GATE)
 123                 WARN_ON(anatop_reg->bypass);
 124
 125         *enable = anatop_reg->bypass;
 126         return 0;
 127 }
 128
 129 static int anatop_regmap_set_bypass(struct regulator_dev *reg, bool enable)
 130 {
 131         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
 132         int sel;
 133
 134         if (enable == anatop_reg->bypass)
 135                 return 0;
 136
 137         sel = enable ? LDO_FET_FULL_ON : anatop_reg->sel;
 138         anatop_reg->bypass = enable;
 139
 140         return regulator_set_voltage_sel_regmap(reg, sel);
 141 }
 142
 143 static struct regulator_ops anatop_rops = {
 144         .set_voltage_sel = regulator_set_voltage_sel_regmap,
 145         .get_voltage_sel = regulator_get_voltage_sel_regmap,
 146         .list_voltage = regulator_list_voltage_linear,
 147         .map_voltage = regulator_map_voltage_linear,
 148 };
 149
 150 static struct regulator_ops anatop_core_rops = {
 151         .enable = anatop_regmap_enable,
 152         .disable = anatop_regmap_disable,
 153         .is_enabled = anatop_regmap_is_enabled,
 154         .set_voltage_sel = anatop_regmap_core_set_voltage_sel,
 155         .set_voltage_time_sel = anatop_regmap_set_voltage_time_sel,
 156         .get_voltage_sel = anatop_regmap_core_get_voltage_sel,
 157         .list_voltage = regulator_list_voltage_linear,
 158         .map_voltage = regulator_map_voltage_linear,
 159         .get_bypass = anatop_regmap_get_bypass,
 160         .set_bypass = anatop_regmap_set_bypass,
 161 };
 162
 163 static int anatop_regulator_probe(struct platform_device *pdev)
 164 {
 165         struct device *dev = &pdev->dev;
 166         struct device_node *np = dev->of_node;
 167         struct device_node *anatop_np;
 168         struct regulator_desc *rdesc;
 169         struct regulator_dev *rdev;
 170         struct anatop_regulator *sreg;
 171         struct regulator_init_data *initdata;
 172         struct regulator_config config = { };
 173         int ret = 0;
 174         u32 val;
 175
 176         sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL);
 177         if (!sreg)
 178                 return -ENOMEM;
 179
 180         rdesc = &sreg->rdesc;
 181         rdesc->type = REGULATOR_VOLTAGE;
 182         rdesc->owner = THIS_MODULE;
 183
 184         of_property_read_string(np, "regulator-name", &rdesc->name);
 185         if (!rdesc->name) {
 186                 dev_err(dev, "failed to get a regulator-name\n");
 187                 return -EINVAL;
 188         }
 189
 190         initdata = of_get_regulator_init_data(dev, np, rdesc);
 191         if (!initdata)
 192                 return -ENOMEM;
 193
 194         initdata->supply_regulator = "vin";
 195         sreg->initdata = initdata;
 196
 197         anatop_np = of_get_parent(np);
 198         if (!anatop_np)
 199                 return -ENODEV;
 200         sreg->anatop = syscon_node_to_regmap(anatop_np);
 201         of_node_put(anatop_np);
 202         if (IS_ERR(sreg->anatop))
 203                 return PTR_ERR(sreg->anatop);
 204
 205         ret = of_property_read_u32(np, "anatop-reg-offset",
 206                                    &sreg->control_reg);
 207         if (ret) {
 208                 dev_err(dev, "no anatop-reg-offset property set\n");
 209                 return ret;
 210         }
 211         ret = of_property_read_u32(np, "anatop-vol-bit-width",
 212                                    &sreg->vol_bit_width);
 213         if (ret) {
 214                 dev_err(dev, "no anatop-vol-bit-width property set\n");
 215                 return ret;
 216         }
 217         ret = of_property_read_u32(np, "anatop-vol-bit-shift",
 218                                    &sreg->vol_bit_shift);
 219         if (ret) {
 220                 dev_err(dev, "no anatop-vol-bit-shift property set\n");
 221                 return ret;
 222         }
 223         ret = of_property_read_u32(np, "anatop-min-bit-val",
 224                                    &sreg->min_bit_val);
 225         if (ret) {
 226                 dev_err(dev, "no anatop-min-bit-val property set\n");
 227                 return ret;
 228         }
 229         ret = of_property_read_u32(np, "anatop-min-voltage",
 230                                    &sreg->min_voltage);
 231         if (ret) {
 232                 dev_err(dev, "no anatop-min-voltage property set\n");
 233                 return ret;
 234         }
 235         ret = of_property_read_u32(np, "anatop-max-voltage",
 236                                    &sreg->max_voltage);
 237         if (ret) {
 238                 dev_err(dev, "no anatop-max-voltage property set\n");
 239                 return ret;
 240         }
 241
 242         /* read LDO ramp up setting, only for core reg */
 243         of_property_read_u32(np, "anatop-delay-reg-offset",
 244                              &sreg->delay_reg);
 245         of_property_read_u32(np, "anatop-delay-bit-width",
 246                              &sreg->delay_bit_width);
 247         of_property_read_u32(np, "anatop-delay-bit-shift",
 248                              &sreg->delay_bit_shift);
 249
 250         rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage) / 25000 + 1
 251                             + sreg->min_bit_val;
 252         rdesc->min_uV = sreg->min_voltage;
 253         rdesc->uV_step = 25000;
 254         rdesc->linear_min_sel = sreg->min_bit_val;
 255         rdesc->vsel_reg = sreg->control_reg;
 256         rdesc->vsel_mask = ((1 << sreg->vol_bit_width) - 1) <<
 257                            sreg->vol_bit_shift;
 258         rdesc->min_dropout_uV = 125000;
 259
 260         config.dev = &pdev->dev;
 261         config.init_data = initdata;
 262         config.driver_data = sreg;
 263         config.of_node = pdev->dev.of_node;
 264         config.regmap = sreg->anatop;
 265
 266         /* Only core regulators have the ramp up delay configuration. */
 267         if (sreg->control_reg && sreg->delay_bit_width) {
 268                 rdesc->ops = &anatop_core_rops;
 269
 270                 ret = regmap_read(config.regmap, rdesc->vsel_reg, &val);
 271                 if (ret) {
 272                         dev_err(dev, "failed to read initial state\n");
 273                         return ret;
 274                 }
 275
 276                 sreg->sel = (val & rdesc->vsel_mask) >> sreg->vol_bit_shift;
 277                 if (sreg->sel == LDO_FET_FULL_ON) {
 278                         sreg->sel = 0;
 279                         sreg->bypass = true;
 280                 }
 281
 282                 /*
 283                  * In case vddpu was disabled by the bootloader, we need to set
 284                  * a sane default until imx6-cpufreq was probed and changes the
 285                  * voltage to the correct value. In this case we set 1.25V.
 286                  */
 287                 if (!sreg->sel && !strcmp(rdesc->name, "vddpu"))
 288                         sreg->sel = 22;
 289
 290                 /* set the default voltage of the pcie phy to be 1.100v */
 291                 if (!sreg->sel && !strcmp(rdesc->name, "vddpcie"))
 292                         sreg->sel = 0x10;
 293
 294                 if (!sreg->bypass && !sreg->sel) {
 295                         dev_err(&pdev->dev, "Failed to read a valid default voltage selector.\n");
 296                         return -EINVAL;
 297                 }
 298         } else {
 299                 u32 enable_bit;
 300
 301                 rdesc->ops = &anatop_rops;
 302
 303                 if (!of_property_read_u32(np, "anatop-enable-bit",
 304                                           &enable_bit)) {
 305                         anatop_rops.enable  = regulator_enable_regmap;
 306                         anatop_rops.disable = regulator_disable_regmap;
 307                         anatop_rops.is_enabled = regulator_is_enabled_regmap;
 308
 309                         rdesc->enable_reg = sreg->control_reg;
 310                         rdesc->enable_mask = BIT(enable_bit);
 311                 }
 312         }
 313
 314         /* register regulator */
 315         rdev = devm_regulator_register(dev, rdesc, &config);
 316         if (IS_ERR(rdev)) {
 317                 dev_err(dev, "failed to register %s\n",
 318                         rdesc->name);
 319                 return PTR_ERR(rdev);
 320         }
 321
 322         platform_set_drvdata(pdev, rdev);
 323
 324         return 0;
 325 }
 326
 327 static const struct of_device_id of_anatop_regulator_match_tbl[] = {
 328         { .compatible = "fsl,anatop-regulator", },
 329         { /* end */ }
 330 };
 331 MODULE_DEVICE_TABLE(of, of_anatop_regulator_match_tbl);
 332
 333 static struct platform_driver anatop_regulator_driver = {
 334         .driver = {
 335                 .name   = "anatop_regulator",
 336                 .of_match_table = of_anatop_regulator_match_tbl,
 337         },
 338         .probe  = anatop_regulator_probe,
 339 };
 340
 341 static int __init anatop_regulator_init(void)
 342 {
 343         return platform_driver_register(&anatop_regulator_driver);
 344 }
 345 postcore_initcall(anatop_regulator_init);
 346
 347 static void __exit anatop_regulator_exit(void)
 348 {
 349         platform_driver_unregister(&anatop_regulator_driver);
 350 }
 351 module_exit(anatop_regulator_exit);
 352
 353 MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>");
 354 MODULE_AUTHOR("Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>");
 355 MODULE_DESCRIPTION("ANATOP Regulator driver");
 356 MODULE_LICENSE("GPL v2");
 357 MODULE_ALIAS("platform:anatop_regulator");