drivers/regulator/rt4801-regulator.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2
   3 #include <linux/gpio/consumer.h>
   4 #include <linux/i2c.h>
   5 #include <linux/kernel.h>
   6 #include <linux/module.h>
   7 #include <linux/of.h>
   8 #include <linux/regmap.h>
   9 #include <linux/regulator/driver.h>
  10
  11 #define RT4801_REG_VOP  0x00
  12 #define RT4801_REG_VON  0x01
  13 #define RT4801_REG_APPS 0x03
  14
  15 #define VOUT_MASK       0x1F
  16
  17 #define MIN_UV          4000000
  18 #define STEP_UV         100000
  19 #define MAX_UV          6000000
  20 #define N_VOLTAGES      ((MAX_UV - MIN_UV) / STEP_UV + 1)
  21
  22 #define DSV_OUT_POS     0
  23 #define DSV_OUT_NEG     1
  24 #define DSV_OUT_MAX     2
  25
  26 #define DSVP_ENABLE     BIT(0)
  27 #define DSVN_ENABLE     BIT(1)
  28 #define DSVALL_ENABLE   (DSVP_ENABLE | DSVN_ENABLE)
  29
  30 struct rt4801_priv {
  31         struct device *dev;
  32         struct gpio_desc *enable_gpios[DSV_OUT_MAX];
  33         unsigned int enable_flag;
  34         unsigned int volt_sel[DSV_OUT_MAX];
  35 };
  36
  37 static int rt4801_of_parse_cb(struct device_node *np,
  38                               const struct regulator_desc *desc,
  39                               struct regulator_config *config)
  40 {
  41         struct rt4801_priv *priv = config->driver_data;
  42         int id = desc->id;
  43
  44         if (priv->enable_gpios[id]) {
  45                 dev_warn(priv->dev, "duplicated enable-gpios property\n");
  46                 return 0;
  47         }
  48         priv->enable_gpios[id] = devm_fwnode_gpiod_get_index(priv->dev,
  49                                                              of_fwnode_handle(np),
  50                                                              "enable", 0,
  51                                                              GPIOD_OUT_HIGH,
  52                                                              "rt4801");
  53         if (IS_ERR(priv->enable_gpios[id]))
  54                 priv->enable_gpios[id] = NULL;
  55
  56         return 0;
  57 }
  58
  59 static int rt4801_set_voltage_sel(struct regulator_dev *rdev, unsigned int selector)
  60 {
  61         struct rt4801_priv *priv = rdev_get_drvdata(rdev);
  62         int id = rdev_get_id(rdev), ret;
  63
  64         if (priv->enable_flag & BIT(id)) {
  65                 ret = regulator_set_voltage_sel_regmap(rdev, selector);
  66                 if (ret)
  67                         return ret;
  68         }
  69
  70         priv->volt_sel[id] = selector;
  71         return 0;
  72 }
  73
  74 static int rt4801_get_voltage_sel(struct regulator_dev *rdev)
  75 {
  76         struct rt4801_priv *priv = rdev_get_drvdata(rdev);
  77         int id = rdev_get_id(rdev);
  78
  79         if (priv->enable_flag & BIT(id))
  80                 return regulator_get_voltage_sel_regmap(rdev);
  81
  82         return priv->volt_sel[id];
  83 }
  84
  85 static int rt4801_enable(struct regulator_dev *rdev)
  86 {
  87         struct rt4801_priv *priv = rdev_get_drvdata(rdev);
  88         int id = rdev_get_id(rdev), ret;
  89
  90         if (!priv->enable_gpios[id]) {
  91                 dev_warn(&rdev->dev, "no dedicated gpio can control\n");
  92                 goto bypass_gpio;
  93         }
  94
  95         gpiod_set_value(priv->enable_gpios[id], 1);
  96
  97 bypass_gpio:
  98         ret = regmap_write(rdev->regmap, rdev->desc->vsel_reg, priv->volt_sel[id]);
  99         if (ret)
 100                 return ret;
 101
 102         priv->enable_flag |= BIT(id);
 103         return 0;
 104 }
 105
 106 static int rt4801_disable(struct regulator_dev *rdev)
 107 {
 108         struct rt4801_priv *priv = rdev_get_drvdata(rdev);
 109         int id = rdev_get_id(rdev);
 110
 111         if (!priv->enable_gpios[id]) {
 112                 dev_warn(&rdev->dev, "no dedicated gpio can control\n");
 113                 goto bypass_gpio;
 114         }
 115
 116         gpiod_set_value(priv->enable_gpios[id], 0);
 117
 118 bypass_gpio:
 119         priv->enable_flag &= ~BIT(id);
 120         return 0;
 121 }
 122
 123 static int rt4801_is_enabled(struct regulator_dev *rdev)
 124 {
 125         struct rt4801_priv *priv = rdev_get_drvdata(rdev);
 126         int id = rdev_get_id(rdev);
 127
 128         return !!(priv->enable_flag & BIT(id));
 129 }
 130
 131 static const struct regulator_ops rt4801_regulator_ops = {
 132         .list_voltage = regulator_list_voltage_linear,
 133         .set_voltage_sel = rt4801_set_voltage_sel,
 134         .get_voltage_sel = rt4801_get_voltage_sel,
 135         .enable = rt4801_enable,
 136         .disable = rt4801_disable,
 137         .is_enabled = rt4801_is_enabled,
 138 };
 139
 140 static const struct regulator_desc rt4801_regulator_descs[] = {
 141         {
 142                 .name = "DSVP",
 143                 .ops = &rt4801_regulator_ops,
 144                 .of_match = of_match_ptr("DSVP"),
 145                 .of_parse_cb = rt4801_of_parse_cb,
 146                 .type = REGULATOR_VOLTAGE,
 147                 .id = DSV_OUT_POS,
 148                 .min_uV = MIN_UV,
 149                 .uV_step = STEP_UV,
 150                 .n_voltages = N_VOLTAGES,
 151                 .owner = THIS_MODULE,
 152                 .vsel_reg = RT4801_REG_VOP,
 153                 .vsel_mask = VOUT_MASK,
 154         },
 155         {
 156                 .name = "DSVN",
 157                 .ops = &rt4801_regulator_ops,
 158                 .of_match = of_match_ptr("DSVN"),
 159                 .of_parse_cb = rt4801_of_parse_cb,
 160                 .type = REGULATOR_VOLTAGE,
 161                 .id = DSV_OUT_NEG,
 162                 .min_uV = MIN_UV,
 163                 .uV_step = STEP_UV,
 164                 .n_voltages = N_VOLTAGES,
 165                 .owner = THIS_MODULE,
 166                 .vsel_reg = RT4801_REG_VON,
 167                 .vsel_mask = VOUT_MASK,
 168         },
 169 };
 170
 171 static const struct regmap_config rt4801_regmap_config = {
 172         .reg_bits = 8,
 173         .val_bits = 8,
 174         .max_register = RT4801_REG_APPS,
 175 };
 176
 177 static int rt4801_probe(struct i2c_client *i2c)
 178 {
 179         struct rt4801_priv *priv;
 180         struct regmap *regmap;
 181         int i;
 182
 183         priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
 184         if (!priv)
 185                 return -ENOMEM;
 186
 187         priv->dev = &i2c->dev;
 188         /* bootloader will on, driver only reconfigure enable to all output high */
 189         priv->enable_flag = DSVALL_ENABLE;
 190
 191         regmap = devm_regmap_init_i2c(i2c, &rt4801_regmap_config);
 192         if (IS_ERR(regmap)) {
 193                 dev_err(&i2c->dev, "Failed to init regmap\n");
 194                 return PTR_ERR(regmap);
 195         }
 196
 197         for (i = 0; i < DSV_OUT_MAX; i++) {
 198                 priv->enable_gpios[i] = devm_gpiod_get_index_optional(&i2c->dev,
 199                                                                       "enable",
 200                                                                       i,
 201                                                                       GPIOD_OUT_HIGH);
 202                 if (IS_ERR(priv->enable_gpios[i])) {
 203                         dev_err(&i2c->dev, "Failed to get gpios\n");
 204                         return PTR_ERR(priv->enable_gpios[i]);
 205                 }
 206         }
 207
 208         for (i = 0; i < DSV_OUT_MAX; i++) {
 209                 const struct regulator_desc *desc = rt4801_regulator_descs + i;
 210                 struct regulator_config config = { .dev = &i2c->dev, .driver_data = priv,
 211                                                    .regmap = regmap, };
 212                 struct regulator_dev *rdev;
 213                 unsigned int val;
 214                 int ret;
 215
 216                 /* initialize volt_sel variable */
 217                 ret = regmap_read(regmap, desc->vsel_reg, &val);
 218                 if (ret)
 219                         return ret;
 220
 221                 priv->volt_sel[i] = val & desc->vsel_mask;
 222
 223                 rdev = devm_regulator_register(&i2c->dev, desc, &config);
 224                 if (IS_ERR(rdev)) {
 225                         dev_err(&i2c->dev, "Failed to register [%d] regulator\n", i);
 226                         return PTR_ERR(rdev);
 227                 }
 228         }
 229
 230         return 0;
 231 }
 232
 233 static const struct of_device_id __maybe_unused rt4801_of_id[] = {
 234         { .compatible = "richtek,rt4801", },
 235         { },
 236 };
 237 MODULE_DEVICE_TABLE(of, rt4801_of_id);
 238
 239 static struct i2c_driver rt4801_driver = {
 240         .driver = {
 241                 .name = "rt4801",
 242                 .of_match_table = of_match_ptr(rt4801_of_id),
 243         },
 244         .probe_new = rt4801_probe,
 245 };
 246 module_i2c_driver(rt4801_driver);
 247
 248 MODULE_AUTHOR("ChiYuan Hwang <cy_huang@richtek.com>");
 249 MODULE_DESCRIPTION("Richtek RT4801 Display Bias Driver");
 250 MODULE_LICENSE("GPL v2");