Quoting Satya Priya (2021-10-28 08:14:31)

Add parenthesis around base as well ((base) + 0x46)

+#define ENABLE_BIT                     BIT(7)
+
+#define LDO_STATUS1_REG(base)          (base + 0x08)
+#define VREG_READY_BIT                 BIT(7)
+
+#define LDO_VSET_LB_REG(base)          (base + 0x40)
+
+#define LDO_STEPPER_CTL_REG(base)      (base + 0x3b)
+#define DEFAULT_VOLTAGE_STEPPER_RATE   38400
+#define STEP_RATE_MASK                 GENMASK(1, 0)
+
+struct regulator_data {
+       const char      *name;
+       const char      *supply_name;
+       int             min_uv;
+       int             max_uv;
+       int             min_dropout_uv;
+};
+
+struct pm8008_regulator {
+       struct device           *dev;
+       struct regmap           *regmap;
+       struct regulator_desc   rdesc;
+       struct regulator_dev    *rdev;
+       struct device_node      *of_node;

This isn't used outside of probe so please drop it. Same goes for any
other struct member that we don't need to keep around beyond probe. Drop
them. rdev?

+       u16                     base;
+       int                     step_rate;
+};
+
+static const struct regulator_data reg_data[] = {
+       /* name  parent      min_uv  max_uv  headroom_uv */
+       { "l1", "vdd_l1_l2",  528000, 1504000, 225000 },
+       { "l2", "vdd_l1_l2",  528000, 1504000, 225000 },
+       { "l3", "vdd_l3_l4", 1504000, 3400000, 200000 },
+       { "l4", "vdd_l3_l4", 1504000, 3400000, 200000 },
+       { "l5", "vdd_l5",    1504000, 3400000, 300000 },
+       { "l6", "vdd_l6",    1504000, 3400000, 300000 },
+       { "l7", "vdd_l7",    1504000, 3400000, 300000 },
+       { }
+};
+
+static int pm8008_regulator_get_voltage(struct regulator_dev *rdev)
+{
+       struct pm8008_regulator *pm8008_reg = rdev_get_drvdata(rdev);
+       __le16 mV;
+       int rc;
+
+       rc = regmap_bulk_read(pm8008_reg->regmap,
+                       LDO_VSET_LB_REG(pm8008_reg->base), (void *)&mV, 2);
+       if (rc < 0) {
+               dev_err(pm8008_reg->dev,
+                                       "failed to read regulator voltage rc=%d\n", rc);

Put it all on one line?

+               return rc;
+       }
+
+       return le16_to_cpu(mV) * 1000;
+}
+
+static inline int pm8008_write_voltage(struct pm8008_regulator *pm8008_reg,
+                                       int min_uv, int max_uv)
+{
+       int rc, mv;
+       u16 vset_raw;
+
+       mv = DIV_ROUND_UP(min_uv, 1000);
+
+       /*
+        * Each LSB of regulator is 1mV and the voltage setpoint
+        * should be multiple of 8mV(step).
+        */
+       mv = DIV_ROUND_UP(mv, VSET_STEP_MV) * VSET_STEP_MV;
+       if (mv * 1000 > max_uv) {
+               dev_err(pm8008_reg->dev,
+                       "requested voltage (%d uV) above maximum limit (%d uV)\n",
+                               mv*1000, max_uv);
+               return -EINVAL;
+       }
+
+       vset_raw = cpu_to_le16(mv);
+
+       rc = regmap_bulk_write(pm8008_reg->regmap,
+                       LDO_VSET_LB_REG(pm8008_reg->base),
+                       (const void *)&vset_raw, sizeof(vset_raw));
+       if (rc < 0) {
+               dev_err(pm8008_reg->dev, "failed to write voltage rc=%d\n", rc);

If this uses the regulator_dev::dev then we'll know which regulator is
failing, instead of just that some regulator failed inside the PMIC.

+               return rc;
+       }
+
+       return 0;
+}
+
+static int pm8008_regulator_set_voltage_time(struct regulator_dev *rdev,
+                               int old_uV, int new_uv)
+{
+       struct pm8008_regulator *pm8008_reg = rdev_get_drvdata(rdev);
+
+       return DIV_ROUND_UP(abs(new_uv - old_uV), pm8008_reg->step_rate);
+}
+
+static int pm8008_regulator_set_voltage(struct regulator_dev *rdev,
+                               int min_uv, int max_uv, unsigned int *selector)
+{
+       struct pm8008_regulator *pm8008_reg = rdev_get_drvdata(rdev);
+       int rc;
+
+       rc = pm8008_write_voltage(pm8008_reg, min_uv, max_uv);
+       if (rc < 0)
+               return rc;
+
+       *selector = DIV_ROUND_UP(min_uv - pm8008_reg->rdesc.min_uV,
+                               VSET_STEP_UV);
+
+       dev_dbg(pm8008_reg->dev, "voltage set to %d\n", min_uv);
+       return 0;
+}
+
+static const struct regulator_ops pm8008_regulator_ops = {
+       .enable                 = regulator_enable_regmap,
+       .disable                = regulator_disable_regmap,
+       .is_enabled             = regulator_is_enabled_regmap,
+       .set_voltage            = pm8008_regulator_set_voltage,

Can we use set_voltage_sel instead?

+       .get_voltage            = pm8008_regulator_get_voltage,
+       .list_voltage           = regulator_list_voltage_linear,
+       .set_voltage_time       = pm8008_regulator_set_voltage_time,
+};
+
+static int pm8008_regulator_of_parse(struct device_node *node,
+                       const struct regulator_desc *desc,
+                       struct regulator_config *config)
+{
+       struct pm8008_regulator *pm8008_reg = config->driver_data;
+       struct device *dev = config->dev;
+       int rc;
+       u8 reg;
+
+       rc = of_property_read_u32(node, "regulator-min-dropout-voltage-microvolt",
+                       &pm8008_reg->rdesc.min_dropout_uV);
+       if (rc) {
+               dev_err(dev, "failed to read min-dropout voltage rc=%d\n", rc);
+               return rc;
+       }
+
+       /* get slew rate */
+       rc = regmap_bulk_read(pm8008_reg->regmap,
+                       LDO_STEPPER_CTL_REG(pm8008_reg->base), (void *)&reg, 1);

Just make reg unsigned int to avoid the cast.

+       if (rc < 0) {
+               dev_err(dev, "%s: failed to read step rate configuration rc=%d\n",
+                               pm8008_reg->rdesc.name, rc);
+               return rc;
+       }

	reg &= STEP_RATE_MASK;
	pm8008_reg->step_rate = DEFAULT_VOLTAGE_STEPPER_RATE >> reg;

+       pm8008_reg->step_rate
+                       = DEFAULT_VOLTAGE_STEPPER_RATE >> (reg & STEP_RATE_MASK);
+
+       return 0;
+}
+
+static int pm8008_regulator_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct device_node *node = pdev->dev.of_node;
+       struct pm8008_regulator *pm8008_reg;
+       struct regmap *regmap;
+       struct regulator_config reg_config = {};
+       const struct regulator_data *reg;
+       struct regulator_init_data *init_data;
+       int rc;
+       u32 base;
+
+       regmap = dev_get_regmap(dev->parent, NULL);
+       if (!regmap) {
+               dev_err(dev, "parent regmap is missing\n");
+               return -EINVAL;
+       }
+
+       for (reg = &reg_data[0]; reg->name; reg++) {
+               pm8008_reg = devm_kzalloc(dev, sizeof(*pm8008_reg), GFP_KERNEL);
+
+               pm8008_reg->regmap = regmap;
+
+               pm8008_reg->of_node = of_get_child_by_name(node, reg->name);

This of_node reference needs to be put somewhere.

+               if (!pm8008_reg->of_node) {
+                       dev_err(dev, "child node %s not found\n", reg->name);
+                       return -ENODEV;
+               }
+
+               pm8008_reg->dev = dev;
+
+               rc = of_property_read_u32(pm8008_reg->of_node, "reg", &base);
+               if (rc < 0) {
+                       dev_err(dev, "%s: failed to get regulator base rc=%d\n",
+                                               reg->name, rc);
+                       return rc;
+               }
+               pm8008_reg->base = base;
+
+               init_data = of_get_regulator_init_data(dev, pm8008_reg->of_node,
+                                                       &pm8008_reg->rdesc);

Is this necessary?

+               if (!init_data) {
+                       dev_err(dev, "%s: failed to get regulator data\n", reg->name);
+                       return -ENODATA;
+               }
+
+               pm8008_reg->rdesc.type = REGULATOR_VOLTAGE;
+               pm8008_reg->rdesc.ops = &pm8008_regulator_ops;
+               pm8008_reg->rdesc.name = init_data->constraints.name;
+               pm8008_reg->rdesc.supply_name = reg->supply_name;
+               pm8008_reg->rdesc.of_match = reg->name;
+               pm8008_reg->rdesc.of_parse_cb = pm8008_regulator_of_parse;
+               pm8008_reg->rdesc.uV_step = VSET_STEP_UV;
+               pm8008_reg->rdesc.min_uV = reg->min_uv;
+               pm8008_reg->rdesc.n_voltages
+                       = ((reg->max_uv - reg->min_uv)
+                               / pm8008_reg->rdesc.uV_step) + 1;
+
+               pm8008_reg->rdesc.enable_reg = LDO_ENABLE_REG(base);
+               pm8008_reg->rdesc.enable_mask = ENABLE_BIT;
+               pm8008_reg->rdesc.min_dropout_uV = reg->min_dropout_uv;
+
+               init_data->constraints.input_uV = init_data->constraints.max_uV;
+               reg_config.dev = dev;
+               reg_config.init_data = init_data;
+               reg_config.driver_data = pm8008_reg;
+               reg_config.of_node = pm8008_reg->of_node;

I think we don't need to do this?

+
+               return PTR_ERR_OR_ZERO(devm_regulator_register(dev, &pm8008_reg->rdesc,
+                                                               &reg_config));

Why are we returning here? Shouldn't we check return value and only
return on failure and otherwise continue with registering the rest of
the regulators?

+       }
+
+       return 0;
+}
+