regulator: DIO5632: add regulator driver for DIO5632

The DIO5632 is designed to support general positive/negative driven
applications. The DIO5632 is primarily intended to supplying TFT LCD
displays, can be used for any application that requires positive and
negative supplies, ranging from ±4V to ±6V and current up to 80mA.

DIO5632 regulator driver supports to enable/disable and set voltage
on its output.

Signed-off-by: Guochun Huang <hero.huang@rock-chips.com>
Change-Id: I0746197fff9368e6c42cb6777a658ea0900e25bd

Documentation/devicetree/bindings/regulator/dio5632-regulator.txt

@@ -0,0 +1,39 @@
+DIO5632 regulators
+
+Required properties:
+- compatible: "DIO5632"
+- reg: I2C slave address
+
+Optional Subnode:
+Device supports two regulators OUTP and OUTN. A sub node within the
+   device node describe the properties of these regulators. The sub-node
+   names must be as follows:
+	-For regulator outp, the sub node name should be "outp".
+	-For regulator outn, the sub node name should be "outn".
+
+-enable-gpios:(active high, output) Regulators are controlled by the input pins.
+   If it is connected to GPIO through host system then provide the
+   gpio number as per gpio.txt.
+
+Each regulator is defined using the standard binding for regulators.
+
+Example:
+
+	dio5632@3e {
+		compatible = "DIO5632";
+		reg = <0x3e>;
+
+		outp {
+			regulator-name = "outp";
+			regulator-boot-on;
+			regulator-always-on;
+			enable-gpios = <&gpio0 RK_PB7 GPIO_ACTIVE_HIGH>;
+		};
+
+		outn {
+			regulator-name = "outn";
+			regulator-boot-on;
+			regulator-always-on;
+			enable-gpios = <&gpio0  RK_PC0 GPIO_ACTIVE_HIGH>;
+		};
+	};

drivers/regulator/Kconfig

@@ -1048,5 +1048,13 @@ config REGULATOR_XZ3216
 	help
 	  Support the voltage and current regulators of the XZ321X series of DCDC devices.
 
+config REGULATOR_DIO5632
+	tristate "DIO5632 Dual Output Power regulators"
+	depends on I2C && GPIOLIB
+	select REGMAP_I2C
+	help
+	  This driver supports DIO5632 single inductor - dual output
+	  power supply specifcally designed for display panels.
+
 endif
 

drivers/regulator/Makefile

@@ -133,5 +133,6 @@ obj-$(CONFIG_REGULATOR_WM8350) += wm8350-regulator.o
 obj-$(CONFIG_REGULATOR_WM8400) += wm8400-regulator.o
 obj-$(CONFIG_REGULATOR_WM8994) += wm8994-regulator.o
 obj-$(CONFIG_REGULATOR_XZ3216) += xz3216.o
+obj-$(CONFIG_REGULATOR_DIO5632) += dio5632-regulator.o
 
 ccflags-$(CONFIG_REGULATOR_DEBUG) += -DDEBUG

drivers/regulator/dio5632-regulator.c

@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2020 Rockchip Electronics Co. Ltd.
+ *
+ * Author: Guochun Huang <hero.huang@rock-chips.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+
+#define DIO5632_REG_VPOS		0x00
+#define DIO5632_REG_VNEG		0x01
+#define DIO5632_REG_APPS_DISP_DISN	0x03
+#define DIO5632_REG_CONTROL		0x0FF
+
+#define DIO5632_VOUT_MASK		0x1F
+#define DIO5632_VOUT_N_VOLTAGE		0x15
+#define DIO5632_VOUT_VMIN		4000000
+#define DIO5632_VOUT_VMAX		6000000
+#define DIO5632_VOUT_STEP		100000
+
+#define DIO5632_REG_DIS_VPOS		BIT(1)
+#define DIO5632_REG_DIS_VNEG		BIT(0)
+
+#define DIO5632_REGULATOR_ID_VPOS	0
+#define DIO5632_REGULATOR_ID_VNEG	1
+#define DIO5632_MAX_REGULATORS		2
+
+#define DIO5632_ACT_DIS_TIME_SLACK		1000
+
+struct DIO5632_reg_pdata {
+	struct gpio_desc *en_gpiod;
+	int ena_gpio_state;
+};
+
+struct DIO5632_regulator {
+	struct device *dev;
+	struct DIO5632_reg_pdata reg_pdata[DIO5632_MAX_REGULATORS];
+};
+
+static int DIO5632_regulator_enable(struct regulator_dev *rdev)
+{
+	struct DIO5632_regulator *dio = rdev_get_drvdata(rdev);
+	int id = rdev_get_id(rdev);
+	struct DIO5632_reg_pdata *rpdata = &dio->reg_pdata[id];
+	int ret;
+
+	if (!IS_ERR(rpdata->en_gpiod)) {
+		gpiod_set_value_cansleep(rpdata->en_gpiod, 1);
+		rpdata->ena_gpio_state = 1;
+	}
+
+	/* Hardware automatically enable discharge bit in enable */
+	if (rdev->constraints->active_discharge ==
+			REGULATOR_ACTIVE_DISCHARGE_DISABLE) {
+		ret = regulator_set_active_discharge_regmap(rdev, false);
+		if (ret < 0) {
+			dev_err(dio->dev, "Failed to disable active discharge: %d\n",
+				ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int DIO5632_regulator_disable(struct regulator_dev *rdev)
+{
+	struct DIO5632_regulator *dio = rdev_get_drvdata(rdev);
+	int id = rdev_get_id(rdev);
+	struct DIO5632_reg_pdata *rpdata = &dio->reg_pdata[id];
+
+	if (!IS_ERR(rpdata->en_gpiod)) {
+		gpiod_set_value_cansleep(rpdata->en_gpiod, 0);
+		rpdata->ena_gpio_state = 0;
+	}
+
+	return 0;
+}
+
+static int DIO5632_regulator_is_enabled(struct regulator_dev *rdev)
+{
+	struct DIO5632_regulator *dio = rdev_get_drvdata(rdev);
+	int id = rdev_get_id(rdev);
+	struct DIO5632_reg_pdata *rpdata = &dio->reg_pdata[id];
+
+	if (!IS_ERR(rpdata->en_gpiod))
+		return rpdata->ena_gpio_state;
+
+	return 1;
+}
+
+static const struct regulator_ops DIO5632_regulator_ops = {
+	.enable = DIO5632_regulator_enable,
+	.disable = DIO5632_regulator_disable,
+	.is_enabled = DIO5632_regulator_is_enabled,
+	.list_voltage = regulator_list_voltage_linear,
+	.map_voltage = regulator_map_voltage_linear,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+	.set_voltage_sel = regulator_set_voltage_sel_regmap,
+	.set_active_discharge = regulator_set_active_discharge_regmap,
+};
+
+static int DIO5632_of_parse_cb(struct device_node *np,
+				const struct regulator_desc *desc,
+				struct regulator_config *config)
+{
+	struct DIO5632_regulator *dio = config->driver_data;
+	struct DIO5632_reg_pdata *rpdata = &dio->reg_pdata[desc->id];
+	int ret;
+
+	rpdata->en_gpiod = devm_fwnode_get_index_gpiod_from_child(dio->dev,
+					"enable", 0, &np->fwnode,
+					GPIOD_OUT_HIGH, "enable");
+	if (IS_ERR_OR_NULL(rpdata->en_gpiod)) {
+		ret = PTR_ERR(rpdata->en_gpiod);
+
+		/* Ignore the error other than probe defer */
+		if (ret == -EPROBE_DEFER)
+			return ret;
+		return 0;
+	}
+
+	return 0;
+}
+
+#define DIO5632_REGULATOR_DESC(_id, _name)		\
+	[DIO5632_REGULATOR_ID_##_id] = {		\
+		.name = "DIO5632-"#_name,		\
+		.supply_name = "vin",			\
+		.id = DIO5632_REGULATOR_ID_##_id,	\
+		.of_match = of_match_ptr(#_name),	\
+		.of_parse_cb	= DIO5632_of_parse_cb,	\
+		.ops = &DIO5632_regulator_ops,		\
+		.n_voltages = DIO5632_VOUT_N_VOLTAGE,	\
+		.min_uV = DIO5632_VOUT_VMIN,		\
+		.uV_step = DIO5632_VOUT_STEP,		\
+		.enable_time = 500,			\
+		.vsel_mask = DIO5632_VOUT_MASK,	\
+		.vsel_reg = DIO5632_REG_##_id,		\
+		.active_discharge_off = 0,			\
+		.active_discharge_on = DIO5632_REG_DIS_##_id, \
+		.active_discharge_mask = DIO5632_REG_DIS_##_id, \
+		.active_discharge_reg = DIO5632_REG_APPS_DISP_DISN, \
+		.type = REGULATOR_VOLTAGE,		\
+		.owner = THIS_MODULE,			\
+	}
+
+static const struct regulator_desc dio_regs_desc[DIO5632_MAX_REGULATORS] = {
+	DIO5632_REGULATOR_DESC(VPOS, outp),
+	DIO5632_REGULATOR_DESC(VNEG, outn),
+};
+
+static const struct regmap_range DIO5632_no_reg_ranges[] = {
+	regmap_reg_range(DIO5632_REG_APPS_DISP_DISN + 1,
+			 DIO5632_REG_CONTROL - 1),
+};
+
+static const struct regmap_access_table DIO5632_no_reg_table = {
+	.no_ranges = DIO5632_no_reg_ranges,
+	.n_no_ranges = ARRAY_SIZE(DIO5632_no_reg_ranges),
+};
+
+static const struct regmap_config DIO5632_regmap_config = {
+	.reg_bits	= 8,
+	.val_bits	= 8,
+	.max_register	= DIO5632_REG_CONTROL,
+	.cache_type	= REGCACHE_NONE,
+	.rd_table	= &DIO5632_no_reg_table,
+	.wr_table	= &DIO5632_no_reg_table,
+};
+
+static int DIO5632_probe(struct i2c_client *client,
+			  const struct i2c_device_id *client_id)
+{
+	struct device *dev = &client->dev;
+	struct DIO5632_regulator *dio;
+	struct regulator_dev *rdev;
+	struct regmap *rmap;
+	struct regulator_config config = { };
+	int id;
+	int ret;
+
+	dio = devm_kzalloc(dev, sizeof(*dio), GFP_KERNEL);
+	if (!dio)
+		return -ENOMEM;
+
+	rmap = devm_regmap_init_i2c(client, &DIO5632_regmap_config);
+	if (IS_ERR(rmap)) {
+		ret = PTR_ERR(rmap);
+		dev_err(dev, "regmap init failed: %d\n", ret);
+		return ret;
+	}
+
+	i2c_set_clientdata(client, dio);
+	dio->dev = dev;
+
+	for (id = 0; id < DIO5632_MAX_REGULATORS; ++id) {
+		config.regmap = rmap;
+		config.dev = dev;
+		config.driver_data = dio;
+
+		rdev = devm_regulator_register(dev, &dio_regs_desc[id],
+					       &config);
+		if (IS_ERR(rdev)) {
+			ret = PTR_ERR(rdev);
+			dev_err(dev, "regulator %s register failed: %d\n",
+				dio_regs_desc[id].name, ret);
+			return ret;
+		}
+	}
+	return 0;
+}
+
+static const struct i2c_device_id DIO5632_id[] = {
+	{.name = "DIO5632",},
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, DIO5632_id);
+
+static struct i2c_driver DIO5632_i2c_driver = {
+	.driver = {
+		.name = "DIO5632",
+	},
+	.probe = DIO5632_probe,
+	.id_table = DIO5632_id,
+};
+
+module_i2c_driver(DIO5632_i2c_driver);
+
+MODULE_DESCRIPTION("DIO5632 regulator driver");
+MODULE_AUTHOR("Guochun Huang <hero.huang@rockchips.com>");
+MODULE_LICENSE("GPL v2");