Commit 3eb2c7ec authored by Philipp Zabel's avatar Philipp Zabel Committed by Mark Brown
Browse files

regulator: Add LTC3589 support 



This patch adds support for the Linear Technology LTC3589, LTC3589-1,
and LTC3589-2 8-output I2C voltage regulator ICs.

Signed-off-by: default avatarLucas Stach <l.stach@pengutronix.de>
Signed-off-by: default avatarPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: default avatarMark Brown <broonie@linaro.org>
parent a3cd1de4

drivers/regulator/Kconfig

+6 −0
Original line number Diff line number Diff line
@@ -265,6 +265,12 @@ config REGULATOR_LP8788 
	help

	  This driver supports LP8788 voltage regulator chip.



config REGULATOR_LTC3589

	bool "LTC3589 8-output voltage regulator"

	help

	  This enables support for the LTC3589, LTC3589-1, and LTC3589-2

	  8-output regulators controlled via I2C.



config REGULATOR_MAX14577

	tristate "Maxim 14577 regulator"

	depends on MFD_MAX14577

drivers/regulator/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -37,6 +37,7 @@ obj-$(CONFIG_REGULATOR_LP872X) += lp872x.o 
obj-$(CONFIG_REGULATOR_LP8788) += lp8788-buck.o

obj-$(CONFIG_REGULATOR_LP8788) += lp8788-ldo.o

obj-$(CONFIG_REGULATOR_LP8755) += lp8755.o

obj-$(CONFIG_REGULATOR_LTC3589) += ltc3589.o

obj-$(CONFIG_REGULATOR_MAX14577) += max14577.o

obj-$(CONFIG_REGULATOR_MAX1586) += max1586.o

obj-$(CONFIG_REGULATOR_MAX8649)	+= max8649.o

drivers/regulator/ltc3589.c

0 → 100644
+565 −0
Original line number Diff line number Diff line 
/*

 * Linear Technology LTC3589,LTC3589-1 regulator support

 *

 * Copyright (c) 2014 Philipp Zabel <p.zabel@pengutronix.de>, Pengutronix

 *

 * See file CREDITS for list of people who contributed to this

 * project.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2

 * as published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 */

#include <linux/i2c.h>

#include <linux/init.h>

#include <linux/interrupt.h>

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/of.h>

#include <linux/regmap.h>

#include <linux/regulator/driver.h>

#include <linux/regulator/of_regulator.h>



#define DRIVER_NAME		"ltc3589"



#define LTC3589_IRQSTAT		0x02

#define LTC3589_SCR1		0x07

#define LTC3589_OVEN		0x10

#define LTC3589_SCR2		0x12

#define LTC3589_PGSTAT		0x13

#define LTC3589_VCCR		0x20

#define LTC3589_CLIRQ		0x21

#define LTC3589_B1DTV1		0x23

#define LTC3589_B1DTV2		0x24

#define LTC3589_VRRCR		0x25

#define LTC3589_B2DTV1		0x26

#define LTC3589_B2DTV2		0x27

#define LTC3589_B3DTV1		0x29

#define LTC3589_B3DTV2		0x2a

#define LTC3589_L2DTV1		0x32

#define LTC3589_L2DTV2		0x33



#define LTC3589_IRQSTAT_PGOOD_TIMEOUT	BIT(3)

#define LTC3589_IRQSTAT_UNDERVOLT_WARN	BIT(4)

#define LTC3589_IRQSTAT_UNDERVOLT_FAULT	BIT(5)

#define LTC3589_IRQSTAT_THERMAL_WARN	BIT(6)

#define LTC3589_IRQSTAT_THERMAL_FAULT	BIT(7)



#define LTC3589_OVEN_SW1		BIT(0)

#define LTC3589_OVEN_SW2		BIT(1)

#define LTC3589_OVEN_SW3		BIT(2)

#define LTC3589_OVEN_BB_OUT		BIT(3)

#define LTC3589_OVEN_LDO2		BIT(4)

#define LTC3589_OVEN_LDO3		BIT(5)

#define LTC3589_OVEN_LDO4		BIT(6)

#define LTC3589_OVEN_SW_CTRL		BIT(7)



#define LTC3589_VCCR_SW1_GO		BIT(0)

#define LTC3589_VCCR_SW2_GO		BIT(2)

#define LTC3589_VCCR_SW3_GO		BIT(4)

#define LTC3589_VCCR_LDO2_GO		BIT(6)



enum ltc3589_variant {

	LTC3589,

	LTC3589_1,

	LTC3589_2,

};



enum ltc3589_reg {

	LTC3589_SW1,

	LTC3589_SW2,

	LTC3589_SW3,

	LTC3589_BB_OUT,

	LTC3589_LDO1,

	LTC3589_LDO2,

	LTC3589_LDO3,

	LTC3589_LDO4,

	LTC3589_NUM_REGULATORS,

};



struct ltc3589_regulator {

	struct regulator_desc desc;



	/* External feedback voltage divider */

	unsigned int r1;

	unsigned int r2;

};



struct ltc3589 {

	struct regmap *regmap;

	struct device *dev;

	enum ltc3589_variant variant;

	struct ltc3589_regulator regulator_descs[LTC3589_NUM_REGULATORS];

	struct regulator_dev *regulators[LTC3589_NUM_REGULATORS];

};



static const int ltc3589_ldo4[] = {

	2800000, 2500000, 1800000, 3300000,

};



static const int ltc3589_12_ldo4[] = {

	1200000, 1800000, 2500000, 3200000,

};



static int ltc3589_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)

{

	struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);

	int sel, shift;



	if (unlikely(ramp_delay <= 0))

		return -EINVAL;



	/* VRRCR slew rate offsets are the same as VCCR go bit offsets */

	shift = ffs(rdev->desc->apply_bit) - 1;



	/* The slew rate can be set to 0.88, 1.75, 3.5, or 7 mV/uS */

	for (sel = 0; sel < 4; sel++) {

		if ((880 << sel) >= ramp_delay) {

			return regmap_update_bits(ltc3589->regmap,

						  LTC3589_VRRCR,

						  0x3 << shift, sel << shift);

		}

	}

	return -EINVAL;

}



static int ltc3589_set_suspend_voltage(struct regulator_dev *rdev, int uV)

{

	struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);

	int sel;



	sel = regulator_map_voltage_linear(rdev, uV, uV);

	if (sel < 0)

		return sel;



	/* DTV2 register follows right after the corresponding DTV1 register */

	return regmap_update_bits(ltc3589->regmap, rdev->desc->vsel_reg + 1,

				  rdev->desc->vsel_mask, sel);

}



static int ltc3589_set_suspend_mode(struct regulator_dev *rdev,

				    unsigned int mode)

{

	struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev);

	int mask, bit = 0;



	/* VCCR reference selects are right next to the VCCR go bits */

	mask = rdev->desc->apply_bit << 1;



	if (mode == REGULATOR_MODE_STANDBY)

		bit = mask;	/* Select DTV2 */



	mask |= rdev->desc->apply_bit;

	bit |= rdev->desc->apply_bit;

	return regmap_update_bits(ltc3589->regmap, LTC3589_VCCR, mask, bit);

}



static int ltc3589_list_voltage_fixed(struct regulator_dev *rdev,

				      unsigned int selector)

{

	if (selector)

		return -EINVAL;



	return rdev->desc->fixed_uV;

}



/* SW1, SW2, SW3, LDO2 */

static struct regulator_ops ltc3589_linear_regulator_ops = {

	.enable = regulator_enable_regmap,

	.disable = regulator_disable_regmap,

	.is_enabled = regulator_is_enabled_regmap,

	.list_voltage = regulator_list_voltage_linear,

	.set_voltage_sel = regulator_set_voltage_sel_regmap,

	.get_voltage_sel = regulator_get_voltage_sel_regmap,

	.set_ramp_delay = ltc3589_set_ramp_delay,

	.set_voltage_time_sel = regulator_set_voltage_time_sel,

	.set_suspend_voltage = ltc3589_set_suspend_voltage,

	.set_suspend_mode = ltc3589_set_suspend_mode,

};



/* BB_OUT, LDO3 */

static struct regulator_ops ltc3589_fixed_regulator_ops = {

	.enable = regulator_enable_regmap,

	.disable = regulator_disable_regmap,

	.is_enabled = regulator_is_enabled_regmap,

	.list_voltage = ltc3589_list_voltage_fixed,

};



/* LDO1 */

static struct regulator_ops ltc3589_standby_regulator_ops = {

	.list_voltage = ltc3589_list_voltage_fixed,

};



/* LDO4 */

static struct regulator_ops ltc3589_table_regulator_ops = {

	.enable = regulator_enable_regmap,

	.disable = regulator_disable_regmap,

	.is_enabled = regulator_is_enabled_regmap,

	.list_voltage = regulator_list_voltage_table,

	.set_voltage_sel = regulator_set_voltage_sel_regmap,

	.get_voltage_sel = regulator_get_voltage_sel_regmap,

};





#define LTC3589_REG(_name, _ops, en_bit, dtv1_reg, dtv_mask, go_bit)	\

	[LTC3589_ ## _name] = {						\

		.desc = {						\

			.name = #_name,					\

			.n_voltages = (dtv_mask) + 1,			\

			.min_uV = (go_bit) ? 362500 : 0,		\

			.uV_step = (go_bit) ? 12500 : 0,		\

			.ramp_delay = (go_bit) ? 1750 : 0,		\

			.fixed_uV = (dtv_mask) ? 0 : 800000,		\

			.ops = &ltc3589_ ## _ops ## _regulator_ops,	\

			.type = REGULATOR_VOLTAGE,			\

			.id = LTC3589_ ## _name,			\

			.owner = THIS_MODULE,				\

			.vsel_reg = (dtv1_reg),			\

			.vsel_mask = (dtv_mask),			\

			.apply_reg = (go_bit) ? LTC3589_VCCR : 0,	\

			.apply_bit = (go_bit),				\

			.enable_reg = (en_bit) ? LTC3589_OVEN : 0,	\

			.enable_mask = (en_bit),			\

		},							\

	}



#define LTC3589_LINEAR_REG(_name, _dtv1)				\

	LTC3589_REG(_name, linear, LTC3589_OVEN_ ## _name,		\

		    LTC3589_ ## _dtv1, 0x1f,				\

		    LTC3589_VCCR_ ## _name ## _GO)



#define LTC3589_FIXED_REG(_name) \

	LTC3589_REG(_name, fixed, LTC3589_OVEN_ ## _name, 0, 0, 0)



static struct ltc3589_regulator ltc3589_regulators[LTC3589_NUM_REGULATORS] = {

	LTC3589_LINEAR_REG(SW1, B1DTV1),

	LTC3589_LINEAR_REG(SW2, B2DTV1),

	LTC3589_LINEAR_REG(SW3, B3DTV1),

	LTC3589_FIXED_REG(BB_OUT),

	LTC3589_REG(LDO1, standby, 0, 0, 0, 0),

	LTC3589_LINEAR_REG(LDO2, L2DTV1),

	LTC3589_FIXED_REG(LDO3),

	LTC3589_REG(LDO4, table, LTC3589_OVEN_LDO4, LTC3589_L2DTV2, 0x60, 0),

};



#ifdef CONFIG_OF

static struct of_regulator_match ltc3589_matches[LTC3589_NUM_REGULATORS] = {

	{ .name = "sw1",    },

	{ .name = "sw2",    },

	{ .name = "sw3",    },

	{ .name = "bb-out", },

	{ .name = "ldo1",   }, /* standby */

	{ .name = "ldo2",   },

	{ .name = "ldo3",   },

	{ .name = "ldo4",   },

};



static int ltc3589_parse_regulators_dt(struct ltc3589 *ltc3589)

{

	struct device *dev = ltc3589->dev;

	struct device_node *node;

	int i, ret;



	node = of_find_node_by_name(dev->of_node, "regulators");

	if (!node) {

		dev_err(dev, "regulators node not found\n");

		return -EINVAL;

	}



	ret = of_regulator_match(dev, node, ltc3589_matches,

				 ARRAY_SIZE(ltc3589_matches));

	of_node_put(node);

	if (ret < 0) {

		dev_err(dev, "Error parsing regulator init data: %d\n", ret);

		return ret;

	}

	if (ret != LTC3589_NUM_REGULATORS) {

		dev_err(dev, "Only %d regulators described in device tree\n",

			ret);

		return -EINVAL;

	}



	/* Parse feedback voltage dividers. LDO3 and LDO4 don't have them */

	for (i = 0; i < LTC3589_LDO3; i++) {

		struct ltc3589_regulator *desc = &ltc3589->regulator_descs[i];

		struct device_node *np = ltc3589_matches[i].of_node;

		u32 vdiv[2];



		ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider",

						 vdiv, 2);

		if (ret) {

			dev_err(dev, "Failed to parse voltage divider: %d\n",

				ret);

			return ret;

		}



		desc->r1 = vdiv[0];

		desc->r2 = vdiv[1];

	}



	return 0;

}



static inline struct regulator_init_data *match_init_data(int index)

{

	return ltc3589_matches[index].init_data;

}



static inline struct device_node *match_of_node(int index)

{

	return ltc3589_matches[index].of_node;

}

#else

static inline int ltc3589_parse_regulators_dt(struct ltc3589 *ltc3589)

{

	return 0;

}



static inline struct regulator_init_data *match_init_data(int index)

{

	return NULL;

}



static inline struct device_node *match_of_node(int index)

{

	return NULL;

}

#endif



static bool ltc3589_writeable_reg(struct device *dev, unsigned int reg)

{

	switch (reg) {

	case LTC3589_IRQSTAT:

	case LTC3589_SCR1:

	case LTC3589_OVEN:

	case LTC3589_SCR2:

	case LTC3589_VCCR:

	case LTC3589_CLIRQ:

	case LTC3589_B1DTV1:

	case LTC3589_B1DTV2:

	case LTC3589_VRRCR:

	case LTC3589_B2DTV1:

	case LTC3589_B2DTV2:

	case LTC3589_B3DTV1:

	case LTC3589_B3DTV2:

	case LTC3589_L2DTV1:

	case LTC3589_L2DTV2:

		return true;

	}

	return false;

}



static bool ltc3589_readable_reg(struct device *dev, unsigned int reg)

{

	switch (reg) {

	case LTC3589_IRQSTAT:

	case LTC3589_SCR1:

	case LTC3589_OVEN:

	case LTC3589_SCR2:

	case LTC3589_PGSTAT:

	case LTC3589_VCCR:

	case LTC3589_B1DTV1:

	case LTC3589_B1DTV2:

	case LTC3589_VRRCR:

	case LTC3589_B2DTV1:

	case LTC3589_B2DTV2:

	case LTC3589_B3DTV1:

	case LTC3589_B3DTV2:

	case LTC3589_L2DTV1:

	case LTC3589_L2DTV2:

		return true;

	}

	return false;

}



static bool ltc3589_volatile_reg(struct device *dev, unsigned int reg)

{

	switch (reg) {

	case LTC3589_IRQSTAT:

	case LTC3589_PGSTAT:

		return true;

	}

	return false;

}



struct reg_default ltc3589_reg_defaults[] = {

	{ LTC3589_SCR1,   0x00 },

	{ LTC3589_OVEN,   0x00 },

	{ LTC3589_SCR2,   0x00 },

	{ LTC3589_VCCR,   0x00 },

	{ LTC3589_B1DTV1, 0x19 },

	{ LTC3589_B1DTV2, 0x19 },

	{ LTC3589_VRRCR,  0xff },

	{ LTC3589_B2DTV1, 0x19 },

	{ LTC3589_B2DTV2, 0x19 },

	{ LTC3589_B3DTV1, 0x19 },

	{ LTC3589_B3DTV2, 0x19 },

	{ LTC3589_L2DTV1, 0x19 },

	{ LTC3589_L2DTV2, 0x19 },

};



static const struct regmap_config ltc3589_regmap_config = {

	.reg_bits = 8,

	.val_bits = 8,

	.writeable_reg = ltc3589_writeable_reg,

	.readable_reg = ltc3589_readable_reg,

	.volatile_reg = ltc3589_volatile_reg,

	.max_register = LTC3589_L2DTV2,

	.reg_defaults = ltc3589_reg_defaults,

	.num_reg_defaults = ARRAY_SIZE(ltc3589_reg_defaults),

	.use_single_rw = true,

	.cache_type = REGCACHE_RBTREE,

};





static irqreturn_t ltc3589_isr(int irq, void *dev_id)

{

	struct ltc3589 *ltc3589 = dev_id;

	unsigned int i, irqstat, event;



	regmap_read(ltc3589->regmap, LTC3589_IRQSTAT, &irqstat);



	if (irqstat & LTC3589_IRQSTAT_THERMAL_WARN) {

		event = REGULATOR_EVENT_OVER_TEMP;

		for (i = 0; i < LTC3589_NUM_REGULATORS; i++)

			regulator_notifier_call_chain(ltc3589->regulators[i],

						      event, NULL);

	}



	if (irqstat & LTC3589_IRQSTAT_UNDERVOLT_WARN) {

		event = REGULATOR_EVENT_UNDER_VOLTAGE;

		for (i = 0; i < LTC3589_NUM_REGULATORS; i++)

			regulator_notifier_call_chain(ltc3589->regulators[i],

						      event, NULL);

	}



	/* Clear warning condition */

	regmap_write(ltc3589->regmap, LTC3589_CLIRQ, 0);



	return IRQ_HANDLED;

}



static inline unsigned int ltc3589_scale(unsigned int uV, u32 r1, u32 r2)

{

	uint64_t tmp;

	if (uV == 0)

		return 0;

	tmp = (uint64_t)uV * r1;

	do_div(tmp, r2);

	return uV + (unsigned int)tmp;

}



static void ltc3589_apply_fb_voltage_divider(struct ltc3589_regulator *rdesc)

{

	struct regulator_desc *desc = &rdesc->desc;



	if (!rdesc->r1 || !rdesc->r2)

		return;



	desc->min_uV = ltc3589_scale(desc->min_uV, rdesc->r1, rdesc->r2);

	desc->uV_step = ltc3589_scale(desc->uV_step, rdesc->r1, rdesc->r2);

	desc->fixed_uV = ltc3589_scale(desc->fixed_uV, rdesc->r1, rdesc->r2);

}



static int ltc3589_probe(struct i2c_client *client,

			 const struct i2c_device_id *id)

{

	struct device *dev = &client->dev;

	struct ltc3589_regulator *descs;

	struct ltc3589 *ltc3589;

	int i, ret;



	ltc3589 = devm_kzalloc(dev, sizeof(*ltc3589), GFP_KERNEL);

	if (!ltc3589)

		return -ENOMEM;



	i2c_set_clientdata(client, ltc3589);

	ltc3589->variant = id->driver_data;

	ltc3589->dev = dev;



	descs = ltc3589->regulator_descs;

	memcpy(descs, ltc3589_regulators, sizeof(ltc3589_regulators));

	if (ltc3589->variant == LTC3589) {

		descs[LTC3589_LDO3].desc.fixed_uV = 1800000;

		descs[LTC3589_LDO4].desc.volt_table = ltc3589_ldo4;

	} else {

		descs[LTC3589_LDO3].desc.fixed_uV = 2800000;

		descs[LTC3589_LDO4].desc.volt_table = ltc3589_12_ldo4;

	}



	ltc3589->regmap = devm_regmap_init_i2c(client, &ltc3589_regmap_config);

	if (IS_ERR(ltc3589->regmap)) {

		ret = PTR_ERR(ltc3589->regmap);

		dev_err(dev, "failed to initialize regmap: %d\n", ret);

		return ret;

	}



	ret = ltc3589_parse_regulators_dt(ltc3589);

	if (ret)

		return ret;



	for (i = 0; i < LTC3589_NUM_REGULATORS; i++) {

		struct ltc3589_regulator *rdesc = &ltc3589->regulator_descs[i];

		struct regulator_desc *desc = &rdesc->desc;

		struct regulator_init_data *init_data;

		struct regulator_config config = { };



		init_data = match_init_data(i);



		if (i < LTC3589_LDO3)

			ltc3589_apply_fb_voltage_divider(rdesc);



		config.dev = dev;

		config.init_data = init_data;

		config.driver_data = ltc3589;

		config.of_node = match_of_node(i);



		ltc3589->regulators[i] = devm_regulator_register(dev, desc,

								 &config);

		if (IS_ERR(ltc3589->regulators[i])) {

			ret = PTR_ERR(ltc3589->regulators[i]);

			dev_err(dev, "failed to register regulator %s: %d\n",

				desc->name, ret);

			return ret;

		}

	}



	ret = devm_request_threaded_irq(dev, client->irq, NULL, ltc3589_isr,

					IRQF_TRIGGER_LOW | IRQF_ONESHOT,

					client->name, ltc3589);

	if (ret) {

		dev_err(dev, "Failed to request IRQ: %d\n", ret);

		return ret;

	}



	return 0;

}



static struct i2c_device_id ltc3589_i2c_id[] = {

	{ "ltc3589",   LTC3589   },

	{ "ltc3589-1", LTC3589_1 },

	{ "ltc3589-2", LTC3589_2 },

	{ }

};

MODULE_DEVICE_TABLE(i2c, ltc3589_i2c_id);



static struct i2c_driver ltc3589_driver = {

	.driver = {

		.name = DRIVER_NAME,

		.owner = THIS_MODULE,

	},

	.probe = ltc3589_probe,

	.id_table = ltc3589_i2c_id,

};

module_i2c_driver(ltc3589_driver);



MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>");

MODULE_DESCRIPTION("Regulator driver for Linear Technology LTC3589(-1,2)");

MODULE_LICENSE("GPL v2");

MODULE_ALIAS("i2c:ltc3589");

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