Merge remote-tracking branches 'regulator/topic/rc5t619' and...

STM32 VREFBUF - Voltage reference buffer

Some STM32 devices embed a voltage reference buffer which can be used as

voltage reference for ADCs, DACs and also as voltage reference for external

components through the dedicated VREF+ pin.

Required properties:

- compatible:		Must be "st,stm32-vrefbuf".

- reg:			Offset and length of VREFBUF register set.

- clocks:		Must contain an entry for peripheral clock.

Example:

	vrefbuf: regulator@58003C00 {

		compatible = "st,stm32-vrefbuf";

		reg = <0x58003C00 0x8>;

		clocks = <&rcc VREF_CK>;

		regulator-min-microvolt = <1500000>;

		regulator-max-microvolt = <2500000>;

		vdda-supply = <&vdda>;

	};

	tristate "Ricoh RN5T567/618 voltage regulators"

	depends on MFD_RN5T618

	help

	  Say y here to support the regulators found on Ricoh RN5T567 or

	  RN5T618 PMIC.

	  Say y here to support the regulators found on Ricoh RN5T567,

	  RN5T618 or RC5T619 PMIC.

config REGULATOR_RT5033

	tristate "Richtek RT5033 Regulators"

	  This driver can also be built as a module. If so, the module

	  will be called sky81452-regulator.

config REGULATOR_STM32_VREFBUF

	tristate "STMicroelectronics STM32 VREFBUF"

	depends on ARCH_STM32 || COMPILE_TEST

	help

	  This driver supports STMicroelectronics STM32 VREFBUF (voltage

	  reference buffer) which can be used as voltage reference for

	  internal ADCs, DACs and also for external components through

	  dedicated Vref+ pin.

	  This driver can also be built as a module. If so, the module

	  will be called stm32-vrefbuf.

config REGULATOR_TI_ABB

	tristate "TI Adaptive Body Bias on-chip LDO"

	depends on ARCH_OMAP

obj-$(CONFIG_REGULATOR_S2MPS11) += s2mps11.o

obj-$(CONFIG_REGULATOR_S5M8767) += s5m8767.o

obj-$(CONFIG_REGULATOR_SKY81452) += sky81452-regulator.o

obj-$(CONFIG_REGULATOR_STM32_VREFBUF) += stm32-vrefbuf.o

obj-$(CONFIG_REGULATOR_STW481X_VMMC) += stw481x-vmmc.o

obj-$(CONFIG_REGULATOR_TI_ABB) += ti-abb-regulator.o

obj-$(CONFIG_REGULATOR_TPS6105X) += tps6105x-regulator.o

	REG(LDORTC2, LDOEN2, BIT(5), LDORTC2DAC, 0x7f, 900000, 3500000, 25000),

};

static struct regulator_desc rc5t619_regulators[] = {

	/* DCDC */

	REG(DCDC1, DC1CTL, BIT(0), DC1DAC, 0xff, 600000, 3500000, 12500),

	REG(DCDC2, DC2CTL, BIT(0), DC2DAC, 0xff, 600000, 3500000, 12500),

	REG(DCDC3, DC3CTL, BIT(0), DC3DAC, 0xff, 600000, 3500000, 12500),

	REG(DCDC4, DC4CTL, BIT(0), DC4DAC, 0xff, 600000, 3500000, 12500),

	REG(DCDC5, DC5CTL, BIT(0), DC5DAC, 0xff, 600000, 3500000, 12500),

	/* LDO */

	REG(LDO1, LDOEN1, BIT(0), LDO1DAC, 0x7f, 900000, 3500000, 25000),

	REG(LDO2, LDOEN1, BIT(1), LDO2DAC, 0x7f, 900000, 3500000, 25000),

	REG(LDO3, LDOEN1, BIT(2), LDO3DAC, 0x7f, 900000, 3500000, 25000),

	REG(LDO4, LDOEN1, BIT(3), LDO4DAC, 0x7f, 900000, 3500000, 25000),

	REG(LDO5, LDOEN1, BIT(4), LDO5DAC, 0x7f, 600000, 3500000, 25000),

	REG(LDO6, LDOEN1, BIT(5), LDO6DAC, 0x7f, 600000, 3500000, 25000),

	REG(LDO7, LDOEN1, BIT(6), LDO7DAC, 0x7f, 900000, 3500000, 25000),

	REG(LDO8, LDOEN1, BIT(7), LDO8DAC, 0x7f, 900000, 3500000, 25000),

	REG(LDO9, LDOEN2, BIT(0), LDO9DAC, 0x7f, 900000, 3500000, 25000),

	REG(LDO10, LDOEN2, BIT(0), LDO10DAC, 0x7f, 900000, 3500000, 25000),

	/* LDO RTC */

	REG(LDORTC1, LDOEN2, BIT(4), LDORTCDAC, 0x7f, 1700000, 3500000, 25000),

	REG(LDORTC2, LDOEN2, BIT(5), LDORTC2DAC, 0x7f, 900000, 3500000, 25000),

};

static int rn5t618_regulator_probe(struct platform_device *pdev)

{

	struct rn5t618 *rn5t618 = dev_get_drvdata(pdev->dev.parent);

	struct regulator_dev *rdev;

	struct regulator_desc *regulators;

	int i;

	int num_regulators = 0;

	switch (rn5t618->variant) {

	case RN5T567:

		regulators = rn5t567_regulators;

		num_regulators = ARRAY_SIZE(rn5t567_regulators);

		break;

	case RN5T618:

		regulators = rn5t618_regulators;

		num_regulators = ARRAY_SIZE(rn5t618_regulators);

		break;

	case RC5T619:

		regulators = rc5t619_regulators;

		num_regulators = ARRAY_SIZE(rc5t619_regulators);

		break;

	default:

		return -EINVAL;

	config.dev = pdev->dev.parent;

	config.regmap = rn5t618->regmap;

	for (i = 0; i < RN5T618_REG_NUM; i++) {

		if (!regulators[i].name)

			continue;

	for (i = 0; i < num_regulators; i++) {

		rdev = devm_regulator_register(&pdev->dev,

					       &regulators[i],

					       &config);

/*

 * Copyright (C) STMicroelectronics 2017

 *

 * Author: Fabrice Gasnier <fabrice.gasnier@st.com>

 *

 * License terms:  GNU General Public License (GPL), version 2

 */

#include <linux/bitfield.h>

#include <linux/clk.h>

#include <linux/io.h>

#include <linux/iopoll.h>

#include <linux/module.h>

#include <linux/of_device.h>

#include <linux/platform_device.h>

#include <linux/regulator/driver.h>

#include <linux/regulator/of_regulator.h>

/* STM32 VREFBUF registers */

#define STM32_VREFBUF_CSR		0x00

/* STM32 VREFBUF CSR bitfields */

#define STM32_VRS			GENMASK(6, 4)

#define STM32_VRR			BIT(3)

#define STM32_HIZ			BIT(1)

#define STM32_ENVR			BIT(0)

struct stm32_vrefbuf {

	void __iomem *base;

	struct clk *clk;

};

static const unsigned int stm32_vrefbuf_voltages[] = {

	/* Matches resp. VRS = 000b, 001b, 010b, 011b */

	2500000, 2048000, 1800000, 1500000,

};

static int stm32_vrefbuf_enable(struct regulator_dev *rdev)

{

	struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);

	u32 val = readl_relaxed(priv->base + STM32_VREFBUF_CSR);

	int ret;

	val = (val & ~STM32_HIZ) | STM32_ENVR;

	writel_relaxed(val, priv->base + STM32_VREFBUF_CSR);

	/*

	 * Vrefbuf startup time depends on external capacitor: wait here for

	 * VRR to be set. That means output has reached expected value.

	 * ~650us sleep should be enough for caps up to 1.5uF. Use 10ms as

	 * arbitrary timeout.

	 */

	ret = readl_poll_timeout(priv->base + STM32_VREFBUF_CSR, val,

				 !(val & STM32_VRR), 650, 10000);

	if (ret) {

		dev_err(&rdev->dev, "stm32 vrefbuf timed out!\n");

		val = readl_relaxed(priv->base + STM32_VREFBUF_CSR);

		val = (val & ~STM32_ENVR) | STM32_HIZ;

		writel_relaxed(val, priv->base + STM32_VREFBUF_CSR);

	}

	return ret;

}

static int stm32_vrefbuf_disable(struct regulator_dev *rdev)

{

	struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);

	u32 val = readl_relaxed(priv->base + STM32_VREFBUF_CSR);

	val = (val & ~STM32_ENVR) | STM32_HIZ;

	writel_relaxed(val, priv->base + STM32_VREFBUF_CSR);

	return 0;

}

static int stm32_vrefbuf_is_enabled(struct regulator_dev *rdev)

{

	struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);

	return readl_relaxed(priv->base + STM32_VREFBUF_CSR) & STM32_ENVR;

}

static int stm32_vrefbuf_set_voltage_sel(struct regulator_dev *rdev,

					 unsigned sel)

{

	struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);

	u32 val = readl_relaxed(priv->base + STM32_VREFBUF_CSR);

	val = (val & ~STM32_VRS) | FIELD_PREP(STM32_VRS, sel);

	writel_relaxed(val, priv->base + STM32_VREFBUF_CSR);

	return 0;

}

static int stm32_vrefbuf_get_voltage_sel(struct regulator_dev *rdev)

{

	struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);

	u32 val = readl_relaxed(priv->base + STM32_VREFBUF_CSR);

	return FIELD_GET(STM32_VRS, val);

}

static const struct regulator_ops stm32_vrefbuf_volt_ops = {

	.enable		= stm32_vrefbuf_enable,

	.disable	= stm32_vrefbuf_disable,

	.is_enabled	= stm32_vrefbuf_is_enabled,

	.get_voltage_sel = stm32_vrefbuf_get_voltage_sel,

	.set_voltage_sel = stm32_vrefbuf_set_voltage_sel,

	.list_voltage	= regulator_list_voltage_table,

};

static const struct regulator_desc stm32_vrefbuf_regu = {

	.name = "vref",

	.supply_name = "vdda",

	.volt_table = stm32_vrefbuf_voltages,

	.n_voltages = ARRAY_SIZE(stm32_vrefbuf_voltages),

	.ops = &stm32_vrefbuf_volt_ops,

	.type = REGULATOR_VOLTAGE,

	.owner = THIS_MODULE,

};

static int stm32_vrefbuf_probe(struct platform_device *pdev)

{

	struct resource *res;

	struct stm32_vrefbuf *priv;

	struct regulator_config config = { };

	struct regulator_dev *rdev;

	int ret;

	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);

	if (!priv)

		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	priv->base = devm_ioremap_resource(&pdev->dev, res);

	if (IS_ERR(priv->base))

		return PTR_ERR(priv->base);

	priv->clk = devm_clk_get(&pdev->dev, NULL);

	if (IS_ERR(priv->clk))

		return PTR_ERR(priv->clk);

	ret = clk_prepare_enable(priv->clk);

	if (ret) {

		dev_err(&pdev->dev, "clk prepare failed with error %d\n", ret);

		return ret;

	}

	config.dev = &pdev->dev;

	config.driver_data = priv;

	config.of_node = pdev->dev.of_node;

	config.init_data = of_get_regulator_init_data(&pdev->dev,

						      pdev->dev.of_node,

						      &stm32_vrefbuf_regu);

	rdev = regulator_register(&stm32_vrefbuf_regu, &config);

	if (IS_ERR(rdev)) {

		ret = PTR_ERR(rdev);

		dev_err(&pdev->dev, "register failed with error %d\n", ret);

		goto err_clk_dis;

	}

	platform_set_drvdata(pdev, rdev);

	return 0;

err_clk_dis:

	clk_disable_unprepare(priv->clk);

	return ret;

}

static int stm32_vrefbuf_remove(struct platform_device *pdev)

{

	struct regulator_dev *rdev = platform_get_drvdata(pdev);

	struct stm32_vrefbuf *priv = rdev_get_drvdata(rdev);

	regulator_unregister(rdev);

	clk_disable_unprepare(priv->clk);

	return 0;

};

static const struct of_device_id stm32_vrefbuf_of_match[] = {

	{ .compatible = "st,stm32-vrefbuf", },

	{},

};

MODULE_DEVICE_TABLE(of, stm32_vrefbuf_of_match);

static struct platform_driver stm32_vrefbuf_driver = {

	.probe = stm32_vrefbuf_probe,

	.remove = stm32_vrefbuf_remove,

	.driver = {

		.name  = "stm32-vrefbuf",

		.of_match_table = of_match_ptr(stm32_vrefbuf_of_match),

	},

};

module_platform_driver(stm32_vrefbuf_driver);

MODULE_LICENSE("GPL v2");

MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");

MODULE_DESCRIPTION("STMicroelectronics STM32 VREFBUF driver");

MODULE_ALIAS("platform:stm32-vrefbuf");