diff options
Diffstat (limited to 'drivers/regulator/ltc3589.c')
| -rw-r--r-- | drivers/regulator/ltc3589.c | 554 | 
1 files changed, 554 insertions, 0 deletions
diff --git a/drivers/regulator/ltc3589.c b/drivers/regulator/ltc3589.c new file mode 100644 index 00000000000..c8105182b8b --- /dev/null +++ b/drivers/regulator/ltc3589.c @@ -0,0 +1,554 @@ +/* + * 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); +} + +/* 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, +}; + +/* LDO1 */ +static struct regulator_ops ltc3589_fixed_standby_regulator_ops = { +}; + +/* 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 = <c3589_ ## _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, fixed_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_get_child_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 = <c3589->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, <c3589_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 = <c3589->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");  | 
