Unverified Commit 5bbbfc7f authored by ChiYuan Huang's avatar ChiYuan Huang Committed by Mark Brown
Browse files

regulator: rt4801: Add support for RT4801 Display Bias regulator driver 



Adds support for the RT4801 DSV. It has two regulators (DSVP/DSVN) with
an I2C interface. DSVP/DSVN can provide the display panel module for the
positive/negative voltage range from (+/-)4V to (+/-)6V.

Signed-off-by: default avatarChiYuan Huang <cy_huang@richtek.com>
Link: https://lore.kernel.org/r/1597461262-25878-1-git-send-email-u0084500@gmail.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent b2ad0be5

drivers/regulator/Kconfig

+7 −0
Original line number Diff line number Diff line
@@ -894,6 +894,13 @@ config REGULATOR_RN5T618 
config REGULATOR_ROHM

	tristate



config REGULATOR_RT4801

	tristate "Richtek RT4801 Regulators"

	depends on I2C

	help

	  This adds support for voltage regulators in Richtek RT4801 Display Bias IC.

	  The device supports two regulators (DSVP/DSVN).



config REGULATOR_RT5033

	tristate "Richtek RT5033 Regulators"

	depends on MFD_RT5033

drivers/regulator/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -111,6 +111,7 @@ obj-$(CONFIG_REGULATOR_RC5T583) += rc5t583-regulator.o 
obj-$(CONFIG_REGULATOR_RK808)   += rk808-regulator.o

obj-$(CONFIG_REGULATOR_RN5T618) += rn5t618-regulator.o

obj-$(CONFIG_REGULATOR_ROHM)	+= rohm-regulator.o

obj-$(CONFIG_REGULATOR_RT4801)	+= rt4801-regulator.o

obj-$(CONFIG_REGULATOR_RT5033)	+= rt5033-regulator.o

obj-$(CONFIG_REGULATOR_S2MPA01) += s2mpa01.o

obj-$(CONFIG_REGULATOR_S2MPS11) += s2mps11.o

drivers/regulator/rt4801-regulator.c

0 → 100644
+223 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0+



#include <linux/gpio/consumer.h>

#include <linux/i2c.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/regmap.h>

#include <linux/regulator/driver.h>



#define RT4801_REG_VOP	0x00

#define RT4801_REG_VON	0x01

#define RT4801_REG_APPS	0x03



#define VOUT_MASK	0x1F



#define MIN_UV		4000000

#define STEP_UV		100000

#define MAX_UV		6000000

#define N_VOLTAGES	((MAX_UV - MIN_UV) / STEP_UV + 1)



#define DSV_OUT_POS	0

#define DSV_OUT_NEG	1

#define DSV_OUT_MAX	2



#define DSVP_ENABLE	BIT(0)

#define DSVN_ENABLE	BIT(1)

#define DSVALL_ENABLE	(DSVP_ENABLE | DSVN_ENABLE)



struct rt4801_priv {

	struct device *dev;

	struct gpio_descs *enable_gpios;

	unsigned int enable_flag;

	unsigned int volt_sel[DSV_OUT_MAX];

};



static int rt4801_set_voltage_sel(struct regulator_dev *rdev, unsigned int selector)

{

	struct rt4801_priv *priv = rdev_get_drvdata(rdev);

	int id = rdev_get_id(rdev), ret;



	if (priv->enable_flag & BIT(id)) {

		ret = regulator_set_voltage_sel_regmap(rdev, selector);

		if (ret)

			return ret;

	}



	priv->volt_sel[id] = selector;

	return 0;

}



static int rt4801_get_voltage_sel(struct regulator_dev *rdev)

{

	struct rt4801_priv *priv = rdev_get_drvdata(rdev);

	int id = rdev_get_id(rdev);



	if (priv->enable_flag & BIT(id))

		return regulator_get_voltage_sel_regmap(rdev);



	return priv->volt_sel[id];

}



static int rt4801_enable(struct regulator_dev *rdev)

{

	struct rt4801_priv *priv = rdev_get_drvdata(rdev);

	struct gpio_descs *gpios = priv->enable_gpios;

	int id = rdev_get_id(rdev), ret;



	if (gpios->ndescs <= id) {

		dev_warn(&rdev->dev, "no dedicated gpio can control\n");

		goto bypass_gpio;

	}



	gpiod_set_value(gpios->desc[id], 1);



bypass_gpio:

	ret = regmap_write(rdev->regmap, rdev->desc->vsel_reg, priv->volt_sel[id]);

	if (ret)

		return ret;



	priv->enable_flag |= BIT(id);

	return 0;

}



static int rt4801_disable(struct regulator_dev *rdev)

{

	struct rt4801_priv *priv = rdev_get_drvdata(rdev);

	struct gpio_descs *gpios = priv->enable_gpios;

	int id = rdev_get_id(rdev);



	if (gpios->ndescs <= id) {

		dev_warn(&rdev->dev, "no dedicated gpio can control\n");

		goto bypass_gpio;

	}



	gpiod_set_value(gpios->desc[id], 0);



bypass_gpio:

	priv->enable_flag &= ~BIT(id);

	return 0;

}



static int rt4801_is_enabled(struct regulator_dev *rdev)

{

	struct rt4801_priv *priv = rdev_get_drvdata(rdev);

	int id = rdev_get_id(rdev);



	return !!(priv->enable_flag & BIT(id));

}



static const struct regulator_ops rt4801_regulator_ops = {

	.list_voltage = regulator_list_voltage_linear,

	.set_voltage_sel = rt4801_set_voltage_sel,

	.get_voltage_sel = rt4801_get_voltage_sel,

	.enable = rt4801_enable,

	.disable = rt4801_disable,

	.is_enabled = rt4801_is_enabled,

};



static const struct regulator_desc rt4801_regulator_descs[] = {

	{

		.name = "DSVP",

		.ops = &rt4801_regulator_ops,

		.of_match = of_match_ptr("DSVP"),

		.type = REGULATOR_VOLTAGE,

		.id = DSV_OUT_POS,

		.min_uV = MIN_UV,

		.uV_step = STEP_UV,

		.n_voltages = N_VOLTAGES,

		.owner = THIS_MODULE,

		.vsel_reg = RT4801_REG_VOP,

		.vsel_mask = VOUT_MASK,

	},

	{

		.name = "DSVN",

		.ops = &rt4801_regulator_ops,

		.of_match = of_match_ptr("DSVN"),

		.type = REGULATOR_VOLTAGE,

		.id = DSV_OUT_NEG,

		.min_uV = MIN_UV,

		.uV_step = STEP_UV,

		.n_voltages = N_VOLTAGES,

		.owner = THIS_MODULE,

		.vsel_reg = RT4801_REG_VON,

		.vsel_mask = VOUT_MASK,

	},

};



static const struct regmap_config rt4801_regmap_config = {

	.reg_bits = 8,

	.val_bits = 8,

	.max_register = RT4801_REG_APPS,

};



static int rt4801_probe(struct i2c_client *i2c)

{

	struct rt4801_priv *priv;

	struct regmap *regmap;

	int i;



	priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL);

	if (!priv)

		return -ENOMEM;



	priv->dev = &i2c->dev;

	/* bootloader will on, driver only reconfigure enable to all output high */

	priv->enable_flag = DSVALL_ENABLE;



	regmap = devm_regmap_init_i2c(i2c, &rt4801_regmap_config);

	if (IS_ERR(regmap)) {

		dev_err(&i2c->dev, "Failed to init regmap\n");

		return PTR_ERR(regmap);

	}



	priv->enable_gpios = devm_gpiod_get_array_optional(&i2c->dev, "enable", GPIOD_OUT_HIGH);

	if (IS_ERR(priv->enable_gpios)) {

		dev_err(&i2c->dev, "Failed to get gpios\n");

		return PTR_ERR(priv->enable_gpios);

	}



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

		const struct regulator_desc *desc = rt4801_regulator_descs + i;

		struct regulator_config config = { .dev = &i2c->dev, .driver_data = priv,

						   .regmap = regmap, };

		struct regulator_dev *rdev;

		unsigned int val;

		int ret;



		/* initialize volt_sel variable */

		ret = regmap_read(regmap, desc->vsel_reg, &val);

		if (ret)

			return ret;



		priv->volt_sel[i] = val & desc->vsel_mask;



		rdev = devm_regulator_register(&i2c->dev, desc, &config);

		if (IS_ERR(rdev)) {

			dev_err(&i2c->dev, "Failed to register [%d] regulator\n", i);

			return PTR_ERR(rdev);

		}

	}



	return 0;

}



static const struct of_device_id rt4801_of_id[] = {

	{ .compatible = "richtek,rt4801", },

	{ },

};

MODULE_DEVICE_TABLE(of, rt4801_of_id);



static struct i2c_driver rt4801_driver = {

	.driver = {

		.name = "rt4801",

		.of_match_table = of_match_ptr(rt4801_of_id),

	},

	.probe_new = rt4801_probe,

};

module_i2c_driver(rt4801_driver);



MODULE_AUTHOR("ChiYuan Hwang <cy_huang@richtek.com>");

MODULE_DESCRIPTION("Richtek RT4801 Display Bias Driver");

MODULE_LICENSE("GPL v2");