regulator Add Richtek RT5759 buck converter support

Merge series from cy_huang <u0084500@gmail.com>:

This patch series add Richtek RT5759 buck converter support.

4 files changed, 470 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/regulator/richtek,rt5759-regulator.yaml b/Documentation/devicetree/bindings/regulator/richtek,rt5759-regulator.yaml
new file mode 100644
index 000000000000..0a4c9576a432
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/richtek,rt5759-regulator.yaml
@@ -0,0 +1,90 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/regulator/richtek,rt5759-regulator.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Richtek RT5759 High Performance DCDC Converter
+
+maintainers:
+  - ChiYuan Huang <cy_huang@richtek.com>
+
+description: |
+  The RT5759 is a high-performance, synchronous step-down DC-DC converter that
+  can deliver up to 9A output current from 3V to 6.5V input supply, The output
+  voltage can be programmable with I2C controlled 7-Bit VID.
+
+  Datasheet is available at
+  https://www.richtek.com/assets/product_file/RT5759/DS5759-00.pdf
+
+properties:
+  compatible:
+    enum:
+      - richtek,rt5759
+      - richtek,rt5759a
+
+  reg:
+    maxItems: 1
+
+  regulator-allowed-modes:
+    description: |
+      buck allowed operating mode
+        0: auto mode (PSKIP: pulse skipping)
+        1: force pwm mode
+    items:
+      enum: [0, 1]
+
+  richtek,watchdog-enable:
+    description: enable the external watchdog reset pin listening
+    type: boolean
+
+allOf:
+  - $ref: regulator.yaml#
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: richtek,rt5759
+    then:
+      properties:
+        richtek,watchdog-enable: false
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  # example 1 for RT5759
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      regulator@62 {
+        compatible = "richtek,rt5759";
+        reg = <0x62>;
+        regulator-name = "rt5759-buck";
+        regulator-min-microvolt = <600000>;
+        regulator-max-microvolt = <1500000>;
+        regulator-boot-on;
+      };
+    };
+  # example 2 for RT5759A
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      regulator@62 {
+        compatible = "richtek,rt5759a";
+        reg = <0x62>;
+        regulator-name = "rt5759a-buck";
+        regulator-min-microvolt = <600000>;
+        regulator-max-microvolt = <1725000>;
+        regulator-boot-on;
+        richtek,watchdog-enable;
+      };
+    };
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 5ef2306fce04..a7effc57bbdb 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -1057,6 +1057,16 @@ config REGULATOR_RT5190A
 	  buck converters, 1 LDO, mute AC OFF depop function, with the general
 	  I2C control interface.
 
+config REGULATOR_RT5759
+	tristate "Richtek RT5759 Regulator"
+	depends on I2C
+	select REGMAP_I2C
+	help
+	  This adds support for voltage regulator in Richtek RT5759.
+	  The RT5759 is a high-performance, synchronous step-down DC-DC
+	  converter that can deliver up to 9A output current from 3V to 6.5V
+	  input supply.
+
 config REGULATOR_RT6160
 	tristate "Richtek RT6160 BuckBoost voltage regulator"
 	depends on I2C
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 1b64ad5767be..69b5a196acd2 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -127,6 +127,7 @@ obj-$(CONFIG_REGULATOR_RT4801)	+= rt4801-regulator.o
 obj-$(CONFIG_REGULATOR_RT4831)	+= rt4831-regulator.o
 obj-$(CONFIG_REGULATOR_RT5033)	+= rt5033-regulator.o
 obj-$(CONFIG_REGULATOR_RT5190A) += rt5190a-regulator.o
+obj-$(CONFIG_REGULATOR_RT5759)	+= rt5759-regulator.o
 obj-$(CONFIG_REGULATOR_RT6160)	+= rt6160-regulator.o
 obj-$(CONFIG_REGULATOR_RT6245)	+= rt6245-regulator.o
 obj-$(CONFIG_REGULATOR_RTMV20)	+= rtmv20-regulator.o
diff --git a/drivers/regulator/rt5759-regulator.c b/drivers/regulator/rt5759-regulator.c
new file mode 100644
index 000000000000..6b96899eb27e
--- /dev/null
+++ b/drivers/regulator/rt5759-regulator.c
@@ -0,0 +1,369 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/bits.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/of_regulator.h>
+
+#define RT5759_REG_VENDORINFO	0x00
+#define RT5759_REG_FREQ		0x01
+#define RT5759_REG_VSEL		0x02
+#define RT5759_REG_DCDCCTRL	0x03
+#define RT5759_REG_STATUS	0x04
+#define RT5759_REG_DCDCSET	0x05
+#define RT5759A_REG_WDTEN	0x42
+
+#define RT5759_TSTEP_MASK	GENMASK(3, 2)
+#define RT5759_VSEL_MASK	GENMASK(6, 0)
+#define RT5759_DISCHARGE_MASK	BIT(3)
+#define RT5759_FPWM_MASK	BIT(2)
+#define RT5759_ENABLE_MASK	BIT(1)
+#define RT5759_OT_MASK		BIT(1)
+#define RT5759_UV_MASK		BIT(0)
+#define RT5957_OCLVL_MASK	GENMASK(7, 6)
+#define RT5759_OCLVL_SHIFT	6
+#define RT5957_OTLVL_MASK	GENMASK(5, 4)
+#define RT5759_OTLVL_SHIFT	4
+#define RT5759A_WDTEN_MASK	BIT(1)
+
+#define RT5759_MANUFACTURER_ID	0x82
+/* vsel range 0x00 ~ 0x5A */
+#define RT5759_NUM_VOLTS	91
+#define RT5759_MIN_UV		600000
+#define RT5759_STEP_UV		10000
+#define RT5759A_STEP_UV		12500
+#define RT5759_MINSS_TIMEUS	1500
+
+#define RT5759_PSKIP_MODE	0
+#define RT5759_FPWM_MODE	1
+
+enum {
+	CHIP_TYPE_RT5759 = 0,
+	CHIP_TYPE_RT5759A,
+	CHIP_TYPE_MAX
+};
+
+struct rt5759_priv {
+	struct device *dev;
+	struct regmap *regmap;
+	struct regulator_desc desc;
+	unsigned long chip_type;
+};
+
+static int rt5759_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int mode_val;
+
+	switch (mode) {
+	case REGULATOR_MODE_NORMAL:
+		mode_val = 0;
+		break;
+	case REGULATOR_MODE_FAST:
+		mode_val = RT5759_FPWM_MASK;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return regmap_update_bits(regmap, RT5759_REG_STATUS, RT5759_FPWM_MASK,
+				  mode_val);
+}
+
+static unsigned int rt5759_get_mode(struct regulator_dev *rdev)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int regval;
+	int ret;
+
+	ret = regmap_read(regmap, RT5759_REG_DCDCCTRL, &regval);
+	if (ret)
+		return REGULATOR_MODE_INVALID;
+
+	if (regval & RT5759_FPWM_MASK)
+		return REGULATOR_MODE_FAST;
+
+	return REGULATOR_MODE_NORMAL;
+}
+
+static int rt5759_get_error_flags(struct regulator_dev *rdev,
+				  unsigned int *flags)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	unsigned int status, events = 0;
+	int ret;
+
+	ret = regmap_read(regmap, RT5759_REG_STATUS, &status);
+	if (ret)
+		return ret;
+
+	if (status & RT5759_OT_MASK)
+		events |= REGULATOR_ERROR_OVER_TEMP;
+
+	if (status & RT5759_UV_MASK)
+		events |= REGULATOR_ERROR_UNDER_VOLTAGE;
+
+	*flags = events;
+	return 0;
+}
+
+static int rt5759_set_ocp(struct regulator_dev *rdev, int lim_uA, int severity,
+			  bool enable)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	int ocp_lvl[] = { 9800000, 10800000, 11800000 };
+	unsigned int ocp_regval;
+	int i;
+
+	/* Only support over current protection parameter */
+	if (severity != REGULATOR_SEVERITY_PROT)
+		return 0;
+
+	if (enable) {
+		/* Default ocp level is 10.8A */
+		if (lim_uA == 0)
+			lim_uA = 10800000;
+
+		for (i = 0; i < ARRAY_SIZE(ocp_lvl); i++) {
+			if (lim_uA <= ocp_lvl[i])
+				break;
+		}
+
+		if (i == ARRAY_SIZE(ocp_lvl))
+			i = ARRAY_SIZE(ocp_lvl) - 1;
+
+		ocp_regval = i + 1;
+	} else
+		ocp_regval = 0;
+
+	return regmap_update_bits(regmap, RT5759_REG_DCDCSET, RT5957_OCLVL_MASK,
+				  ocp_regval << RT5759_OCLVL_SHIFT);
+}
+
+static int rt5759_set_otp(struct regulator_dev *rdev, int lim, int severity,
+			  bool enable)
+{
+	struct regmap *regmap = rdev_get_regmap(rdev);
+	int otp_lvl[] = { 140, 150, 170 };
+	unsigned int otp_regval;
+	int i;
+
+	/* Only support over temperature protection parameter */
+	if (severity != REGULATOR_SEVERITY_PROT)
+		return 0;
+
+	if (enable) {
+		/* Default otp level is 150'c */
+		if (lim == 0)
+			lim = 150;
+
+		for (i = 0; i < ARRAY_SIZE(otp_lvl); i++) {
+			if (lim <= otp_lvl[i])
+				break;
+		}
+
+		if (i == ARRAY_SIZE(otp_lvl))
+			i = ARRAY_SIZE(otp_lvl) - 1;
+
+		otp_regval = i + 1;
+	} else
+		otp_regval = 0;
+
+	return regmap_update_bits(regmap, RT5759_REG_DCDCSET, RT5957_OTLVL_MASK,
+				  otp_regval << RT5759_OTLVL_SHIFT);
+}
+
+static const struct regulator_ops rt5759_regulator_ops = {
+	.list_voltage = regulator_list_voltage_linear,
+	.set_voltage_sel = regulator_set_voltage_sel_regmap,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.set_active_discharge = regulator_set_active_discharge_regmap,
+	.set_mode = rt5759_set_mode,
+	.get_mode = rt5759_get_mode,
+	.set_ramp_delay = regulator_set_ramp_delay_regmap,
+	.get_error_flags = rt5759_get_error_flags,
+	.set_over_current_protection = rt5759_set_ocp,
+	.set_thermal_protection = rt5759_set_otp,
+};
+
+static unsigned int rt5759_of_map_mode(unsigned int mode)
+{
+	switch (mode) {
+	case RT5759_FPWM_MODE:
+		return REGULATOR_MODE_FAST;
+	case RT5759_PSKIP_MODE:
+		return REGULATOR_MODE_NORMAL;
+	default:
+		return REGULATOR_MODE_INVALID;
+	}
+}
+
+static const unsigned int rt5759_ramp_table[] = { 20000, 15000, 10000, 5000 };
+
+static int rt5759_regulator_register(struct rt5759_priv *priv)
+{
+	struct device_node *np = priv->dev->of_node;
+	struct regulator_desc *reg_desc = &priv->desc;
+	struct regulator_config reg_cfg;
+	struct regulator_dev *rdev;
+	int ret;
+
+	reg_desc->name = "rt5759-buck";
+	reg_desc->type = REGULATOR_VOLTAGE;
+	reg_desc->owner = THIS_MODULE;
+	reg_desc->ops = &rt5759_regulator_ops;
+	reg_desc->n_voltages = RT5759_NUM_VOLTS;
+	reg_desc->min_uV = RT5759_MIN_UV;
+	reg_desc->uV_step = RT5759_STEP_UV;
+	reg_desc->vsel_reg = RT5759_REG_VSEL;
+	reg_desc->vsel_mask = RT5759_VSEL_MASK;
+	reg_desc->enable_reg = RT5759_REG_DCDCCTRL;
+	reg_desc->enable_mask = RT5759_ENABLE_MASK;
+	reg_desc->active_discharge_reg = RT5759_REG_DCDCCTRL;
+	reg_desc->active_discharge_mask = RT5759_DISCHARGE_MASK;
+	reg_desc->active_discharge_on = RT5759_DISCHARGE_MASK;
+	reg_desc->ramp_reg = RT5759_REG_FREQ;
+	reg_desc->ramp_mask = RT5759_TSTEP_MASK;
+	reg_desc->ramp_delay_table = rt5759_ramp_table;
+	reg_desc->n_ramp_values = ARRAY_SIZE(rt5759_ramp_table);
+	reg_desc->enable_time = RT5759_MINSS_TIMEUS;
+	reg_desc->of_map_mode = rt5759_of_map_mode;
+
+	/*
+	 * RT5759 step uV = 10000
+	 * RT5759A step uV = 12500
+	 */
+	if (priv->chip_type == CHIP_TYPE_RT5759A)
+		reg_desc->uV_step = RT5759A_STEP_UV;
+
+	reg_cfg.dev = priv->dev;
+	reg_cfg.of_node = np;
+	reg_cfg.init_data = of_get_regulator_init_data(priv->dev, np, reg_desc);
+	reg_cfg.regmap = priv->regmap;
+
+	rdev = devm_regulator_register(priv->dev, reg_desc, &reg_cfg);
+	if (IS_ERR(rdev)) {
+		ret = PTR_ERR(rdev);
+		dev_err(priv->dev, "Failed to register regulator (%d)\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int rt5759_init_device_property(struct rt5759_priv *priv)
+{
+	unsigned int val = 0;
+
+	/*
+	 * Only RT5759A support external watchdog input
+	 */
+	if (priv->chip_type != CHIP_TYPE_RT5759A)
+		return 0;
+
+	if (device_property_read_bool(priv->dev, "richtek,watchdog-enable"))
+		val = RT5759A_WDTEN_MASK;
+
+	return regmap_update_bits(priv->regmap, RT5759A_REG_WDTEN,
+				  RT5759A_WDTEN_MASK, val);
+}
+
+static int rt5759_manufacturer_check(struct rt5759_priv *priv)
+{
+	unsigned int vendor;
+	int ret;
+
+	ret = regmap_read(priv->regmap, RT5759_REG_VENDORINFO, &vendor);
+	if (ret)
+		return ret;
+
+	if (vendor != RT5759_MANUFACTURER_ID) {
+		dev_err(priv->dev, "vendor info not correct (%d)\n", vendor);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static bool rt5759_is_accessible_reg(struct device *dev, unsigned int reg)
+{
+	struct rt5759_priv *priv = dev_get_drvdata(dev);
+
+	if (reg <= RT5759_REG_DCDCSET)
+		return true;
+
+	if (priv->chip_type == CHIP_TYPE_RT5759A && reg == RT5759A_REG_WDTEN)
+		return true;
+
+	return false;
+}
+
+static const struct regmap_config rt5759_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = RT5759A_REG_WDTEN,
+	.readable_reg = rt5759_is_accessible_reg,
+	.writeable_reg = rt5759_is_accessible_reg,
+};
+
+static int rt5759_probe(struct i2c_client *i2c)
+{
+	struct rt5759_priv *priv;
+	int ret;
+
+	priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = &i2c->dev;
+	priv->chip_type = (unsigned long)of_device_get_match_data(&i2c->dev);
+	i2c_set_clientdata(i2c, priv);
+
+	priv->regmap = devm_regmap_init_i2c(i2c, &rt5759_regmap_config);
+	if (IS_ERR(priv->regmap)) {
+		ret = PTR_ERR(priv->regmap);
+		dev_err(&i2c->dev, "Failed to allocate regmap (%d)\n", ret);
+		return ret;
+	}
+
+	ret = rt5759_manufacturer_check(priv);
+	if (ret) {
+		dev_err(&i2c->dev, "Failed to check device (%d)\n", ret);
+		return ret;
+	}
+
+	ret = rt5759_init_device_property(priv);
+	if (ret) {
+		dev_err(&i2c->dev, "Failed to init device (%d)\n", ret);
+		return ret;
+	}
+
+	return rt5759_regulator_register(priv);
+}
+
+static const struct of_device_id __maybe_unused rt5759_device_table[] = {
+	{ .compatible = "richtek,rt5759", .data = (void *)CHIP_TYPE_RT5759 },
+	{ .compatible = "richtek,rt5759a", .data = (void *)CHIP_TYPE_RT5759A },
+	{}
+};
+MODULE_DEVICE_TABLE(of, rt5759_device_table);
+
+static struct i2c_driver rt5759_driver = {
+	.driver = {
+		.name = "rt5759",
+		.of_match_table = of_match_ptr(rt5759_device_table),
+	},
+	.probe_new = rt5759_probe,
+};
+module_i2c_driver(rt5759_driver);
+
+MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
+MODULE_DESCRIPTION("Richtek RT5759 Regulator Driver");
+MODULE_LICENSE("GPL v2");