diff options
| -rw-r--r-- | Documentation/devicetree/bindings/regulator/ltc3676.txt | 94 | ||||
| -rw-r--r-- | drivers/regulator/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/regulator/Makefile | 1 | ||||
| -rw-r--r-- | drivers/regulator/ltc3676.c | 420 |
4 files changed, 523 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/regulator/ltc3676.txt b/Documentation/devicetree/bindings/regulator/ltc3676.txt new file mode 100644 index 000000000000..d4eb366ce18c --- /dev/null +++ b/Documentation/devicetree/bindings/regulator/ltc3676.txt @@ -0,0 +1,94 @@ +Linear Technology LTC3676 8-output regulators + +Required properties: +- compatible: "lltc,ltc3676" +- reg: I2C slave address + +Required child node: +- regulators: Contains eight regulator child nodes sw1, sw2, sw3, sw4, + ldo1, ldo2, ldo3, and ldo4, specifying the initialization data as + documented in Documentation/devicetree/bindings/regulator/regulator.txt. + +Each regulator is defined using the standard binding for regulators. The +nodes for sw1, sw2, sw3, sw4, ldo1, ldo2 and ldo4 additionally need to specify +the resistor values of their external feedback voltage dividers: + +Required properties (not on ldo3): +- lltc,fb-voltage-divider: An array of two integers containing the resistor + values R1 and R2 of the feedback voltage divider in ohms. + +Regulators sw1, sw2, sw3, sw4 can regulate the feedback reference from: +412.5mV to 800mV in 12.5 mV steps. The output voltage thus ranges between +0.4125 * (1 + R1/R2) V and 0.8 * (1 + R1/R2) V. + +Regulators ldo1, ldo2, and ldo4 have a fixed 0.725 V reference and thus output +0.725 * (1 + R1/R2) V. The ldo3 regulator is fixed to 1.8 V. The ldo1 standby +regulator can not be disabled and thus should have the regulator-always-on +property set. + +Example: + + ltc3676: pmic@3c { + compatible = "lltc,ltc3676"; + reg = <0x3c>; + + regulators { + sw1_reg: sw1 { + regulator-min-microvolt = <674400>; + regulator-max-microvolt = <1308000>; + lltc,fb-voltage-divider = <127000 200000>; + regulator-ramp-delay = <7000>; + regulator-boot-on; + regulator-always-on; + }; + + sw2_reg: sw2 { + regulator-min-microvolt = <1033310>; + regulator-max-microvolt = <200400>; + lltc,fb-voltage-divider = <301000 200000>; + regulator-ramp-delay = <7000>; + regulator-boot-on; + regulator-always-on; + }; + + sw3_reg: sw3 { + regulator-min-microvolt = <674400>; + regulator-max-microvolt = <130800>; + lltc,fb-voltage-divider = <127000 200000>; + regulator-ramp-delay = <7000>; + regulator-boot-on; + regulator-always-on; + }; + + sw4_reg: sw4 { + regulator-min-microvolt = <868310>; + regulator-max-microvolt = <168400>; + lltc,fb-voltage-divider = <221000 200000>; + regulator-ramp-delay = <7000>; + regulator-boot-on; + regulator-always-on; + }; + + ldo2_reg: ldo2 { + regulator-min-microvolt = <2490375>; + regulator-max-microvolt = <2490375>; + lltc,fb-voltage-divider = <487000 200000>; + regulator-boot-on; + regulator-always-on; + }; + + ldo3_reg: ldo3 { + regulator-min-microvolt = <1800000>; + regulator-max-microvolt = <1800000>; + regulator-boot-on; + }; + + ldo4_reg: ldo4 { + regulator-min-microvolt = <3023250>; + regulator-max-microvolt = <3023250>; + lltc,fb-voltage-divider = <634000 200000>; + regulator-boot-on; + regulator-always-on; + }; + }; + }; diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig index 6c88e31c01f7..527bd6a51ef8 100644 --- a/drivers/regulator/Kconfig +++ b/drivers/regulator/Kconfig @@ -353,6 +353,14 @@ config REGULATOR_LTC3589 This enables support for the LTC3589, LTC3589-1, and LTC3589-2 8-output regulators controlled via I2C. +config REGULATOR_LTC3676 + tristate "LTC3676 8-output voltage regulator" + depends on I2C + select REGMAP_I2C + help + This enables support for the LTC3676 + 8-output regulators controlled via I2C. + config REGULATOR_MAX14577 tristate "Maxim 14577/77836 regulator" depends on MFD_MAX14577 diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile index f3da9eea9ab6..2142a5d3fc08 100644 --- a/drivers/regulator/Makefile +++ b/drivers/regulator/Makefile @@ -47,6 +47,7 @@ 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-$(CONFIG_REGULATOR_LTC3676) += ltc3676.o obj-$(CONFIG_REGULATOR_MAX14577) += max14577-regulator.o obj-$(CONFIG_REGULATOR_MAX1586) += max1586.o obj-$(CONFIG_REGULATOR_MAX77620) += max77620-regulator.o diff --git a/drivers/regulator/ltc3676.c b/drivers/regulator/ltc3676.c new file mode 100644 index 000000000000..e2b476ca2b4d --- /dev/null +++ b/drivers/regulator/ltc3676.c @@ -0,0 +1,420 @@ +/* + * Copyright (C) 2016 Gateworks Corporation, Inc. All Rights Reserved. + * + * 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/machine.h> +#include <linux/regulator/of_regulator.h> + +#define DRIVER_NAME "ltc3676" + +/* LTC3676 Registers */ +#define LTC3676_BUCK1 0x01 +#define LTC3676_BUCK2 0x02 +#define LTC3676_BUCK3 0x03 +#define LTC3676_BUCK4 0x04 +#define LTC3676_LDOA 0x05 +#define LTC3676_LDOB 0x06 +#define LTC3676_SQD1 0x07 +#define LTC3676_SQD2 0x08 +#define LTC3676_CNTRL 0x09 +#define LTC3676_DVB1A 0x0A +#define LTC3676_DVB1B 0x0B +#define LTC3676_DVB2A 0x0C +#define LTC3676_DVB2B 0x0D +#define LTC3676_DVB3A 0x0E +#define LTC3676_DVB3B 0x0F +#define LTC3676_DVB4A 0x10 +#define LTC3676_DVB4B 0x11 +#define LTC3676_MSKIRQ 0x12 +#define LTC3676_MSKPG 0x13 +#define LTC3676_USER 0x14 +#define LTC3676_IRQSTAT 0x15 +#define LTC3676_PGSTATL 0x16 +#define LTC3676_PGSTATRT 0x17 +#define LTC3676_HRST 0x1E +#define LTC3676_CLIRQ 0x1F + +#define LTC3676_DVBxA_REF_SELECT BIT(5) + +#define LTC3676_IRQSTAT_PGOOD_TIMEOUT BIT(3) +#define LTC3676_IRQSTAT_UNDERVOLT_WARN BIT(4) +#define LTC3676_IRQSTAT_UNDERVOLT_FAULT BIT(5) +#define LTC3676_IRQSTAT_THERMAL_WARN BIT(6) +#define LTC3676_IRQSTAT_THERMAL_FAULT BIT(7) + +enum ltc3676_reg { + LTC3676_SW1, + LTC3676_SW2, + LTC3676_SW3, + LTC3676_SW4, + LTC3676_LDO1, + LTC3676_LDO2, + LTC3676_LDO3, + LTC3676_LDO4, + LTC3676_NUM_REGULATORS, +}; + +struct ltc3676 { + struct regmap *regmap; + struct device *dev; + struct regulator_desc regulator_descs[LTC3676_NUM_REGULATORS]; + struct regulator_dev *regulators[LTC3676_NUM_REGULATORS]; +}; + +static int ltc3676_set_suspend_voltage(struct regulator_dev *rdev, int uV) +{ + struct ltc3676 *ltc3676 = rdev_get_drvdata(rdev); + struct device *dev = ltc3676->dev; + int dcdc = rdev_get_id(rdev); + int sel; + + dev_dbg(dev, "%s id=%d uV=%d\n", __func__, dcdc, uV); + sel = regulator_map_voltage_linear(rdev, uV, uV); + if (sel < 0) + return sel; + + /* DVBB register follows right after the corresponding DVBA register */ + return regmap_update_bits(ltc3676->regmap, rdev->desc->vsel_reg + 1, + rdev->desc->vsel_mask, sel); +} + +static int ltc3676_set_suspend_mode(struct regulator_dev *rdev, + unsigned int mode) +{ + struct ltc3676 *ltc3676= rdev_get_drvdata(rdev); + struct device *dev = ltc3676->dev; + int mask, val; + int dcdc = rdev_get_id(rdev); + + dev_dbg(dev, "%s id=%d mode=%d\n", __func__, dcdc, mode); + + mask = LTC3676_DVBxA_REF_SELECT; + switch (mode) { + case REGULATOR_MODE_STANDBY: + val = 0; /* select DVBxA */ + break; + case REGULATOR_MODE_NORMAL: + val = LTC3676_DVBxA_REF_SELECT; /* select DVBxB */ + break; + default: + dev_warn(&rdev->dev, "%s: regulator mode: 0x%x not supported\n", + rdev->desc->name, mode); + return -EINVAL; + } + + return regmap_update_bits(ltc3676->regmap, rdev->desc->vsel_reg, + mask, val); +} + +static inline unsigned int ltc3676_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 int ltc3676_of_parse_cb(struct device_node *np, + const struct regulator_desc *desc, + struct regulator_config *config) +{ + struct ltc3676 *ltc3676 = config->driver_data; + struct regulator_desc *rdesc = <c3676->regulator_descs[desc->id]; + u32 r[2]; + int ret; + + /* LDO3 has a fixed output */ + if (desc->id == LTC3676_LDO3) + return 0; + + ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider", r, 2); + if (ret) { + dev_err(ltc3676->dev, "Failed to parse voltage divider: %d\n", + ret); + return ret; + } + + rdesc->min_uV = ltc3676_scale(desc->min_uV, r[0], r[1]); + rdesc->uV_step = ltc3676_scale(desc->uV_step, r[0], r[1]); + rdesc->fixed_uV = ltc3676_scale(desc->fixed_uV, r[0], r[1]); + + return 0; +} + +/* SW1, SW2, SW3, SW4 linear 0.8V-3.3V with scalar via R1/R2 feeback res */ +static struct regulator_ops ltc3676_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_suspend_voltage = ltc3676_set_suspend_voltage, + .set_suspend_mode = ltc3676_set_suspend_mode, +}; + +/* LDO1 always on fixed 0.8V-3.3V via scalar via R1/R2 feeback res */ +static struct regulator_ops ltc3676_fixed_standby_regulator_ops = { +}; + +/* LDO2, LDO3 fixed (LDO2 has external scalar via R1/R2 feedback res) */ +static struct regulator_ops ltc3676_fixed_regulator_ops = { + .enable = regulator_enable_regmap, + .disable = regulator_disable_regmap, + .is_enabled = regulator_is_enabled_regmap, +}; + +#define LTC3676_REG(_id, _name, _ops, en_reg, en_bit, dvba_reg, dvb_mask) \ + [LTC3676_ ## _id] = { \ + .name = #_name, \ + .of_match = of_match_ptr(#_name), \ + .regulators_node = of_match_ptr("regulators"), \ + .of_parse_cb = ltc3676_of_parse_cb, \ + .n_voltages = (dvb_mask) + 1, \ + .min_uV = (dvba_reg) ? 412500 : 0, \ + .uV_step = (dvba_reg) ? 12500 : 0, \ + .ramp_delay = (dvba_reg) ? 800 : 0, \ + .fixed_uV = (dvb_mask) ? 0 : 725000, \ + .ops = <c3676_ ## _ops ## _regulator_ops, \ + .type = REGULATOR_VOLTAGE, \ + .id = LTC3676_ ## _id, \ + .owner = THIS_MODULE, \ + .vsel_reg = (dvba_reg), \ + .vsel_mask = (dvb_mask), \ + .enable_reg = (en_reg), \ + .enable_mask = (1 << en_bit), \ + } + +#define LTC3676_LINEAR_REG(_id, _name, _en, _dvba) \ + LTC3676_REG(_id, _name, linear, \ + LTC3676_ ## _en, 7, \ + LTC3676_ ## _dvba, 0x1f) + +#define LTC3676_FIXED_REG(_id, _name, _en_reg, _en_bit) \ + LTC3676_REG(_id, _name, fixed, LTC3676_ ## _en_reg, _en_bit, 0, 0) + +static struct regulator_desc ltc3676_regulators[LTC3676_NUM_REGULATORS] = { + LTC3676_LINEAR_REG(SW1, sw1, BUCK1, DVB1A), + LTC3676_LINEAR_REG(SW2, sw2, BUCK2, DVB2A), + LTC3676_LINEAR_REG(SW3, sw3, BUCK3, DVB3A), + LTC3676_LINEAR_REG(SW4, sw4, BUCK4, DVB4A), + LTC3676_REG(LDO1, ldo1, fixed_standby, 0, 0, 0, 0), + LTC3676_FIXED_REG(LDO2, ldo2, LDOA, 2), + LTC3676_FIXED_REG(LDO3, ldo3, LDOA, 5), + LTC3676_FIXED_REG(LDO4, ldo4, LDOB, 2), +}; + +static bool ltc3676_writeable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LTC3676_IRQSTAT: + case LTC3676_BUCK1: + case LTC3676_BUCK2: + case LTC3676_BUCK3: + case LTC3676_BUCK4: + case LTC3676_LDOA: + case LTC3676_LDOB: + case LTC3676_SQD1: + case LTC3676_SQD2: + case LTC3676_CNTRL: + case LTC3676_DVB1A: + case LTC3676_DVB1B: + case LTC3676_DVB2A: + case LTC3676_DVB2B: + case LTC3676_DVB3A: + case LTC3676_DVB3B: + case LTC3676_DVB4A: + case LTC3676_DVB4B: + case LTC3676_MSKIRQ: + case LTC3676_MSKPG: + case LTC3676_USER: + case LTC3676_HRST: + case LTC3676_CLIRQ: + return true; + } + return false; +} + +static bool ltc3676_readable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LTC3676_IRQSTAT: + case LTC3676_BUCK1: + case LTC3676_BUCK2: + case LTC3676_BUCK3: + case LTC3676_BUCK4: + case LTC3676_LDOA: + case LTC3676_LDOB: + case LTC3676_SQD1: + case LTC3676_SQD2: + case LTC3676_CNTRL: + case LTC3676_DVB1A: + case LTC3676_DVB1B: + case LTC3676_DVB2A: + case LTC3676_DVB2B: + case LTC3676_DVB3A: + case LTC3676_DVB3B: + case LTC3676_DVB4A: + case LTC3676_DVB4B: + case LTC3676_MSKIRQ: + case LTC3676_MSKPG: + case LTC3676_USER: + case LTC3676_HRST: + case LTC3676_CLIRQ: + return true; + } + return false; +} + +static bool ltc3676_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LTC3676_IRQSTAT: + case LTC3676_PGSTATL: + case LTC3676_PGSTATRT: + return true; + } + return false; +} + +static const struct regmap_config ltc3676_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .writeable_reg = ltc3676_writeable_reg, + .readable_reg = ltc3676_readable_reg, + .volatile_reg = ltc3676_volatile_reg, + .max_register = LTC3676_CLIRQ, + .use_single_rw = true, + .cache_type = REGCACHE_RBTREE, +}; + +static irqreturn_t ltc3676_isr(int irq, void *dev_id) +{ + struct ltc3676 *ltc3676 = dev_id; + struct device *dev = ltc3676->dev; + unsigned int i, irqstat, event; + + regmap_read(ltc3676->regmap, LTC3676_IRQSTAT, &irqstat); + + dev_dbg(dev, "irq%d irqstat=0x%02x\n", irq, irqstat); + if (irqstat & LTC3676_IRQSTAT_THERMAL_WARN) { + dev_warn(dev, "Over-temperature Warning\n"); + event = REGULATOR_EVENT_OVER_TEMP; + for (i = 0; i < LTC3676_NUM_REGULATORS; i++) + regulator_notifier_call_chain(ltc3676->regulators[i], + event, NULL); + } + + if (irqstat & LTC3676_IRQSTAT_UNDERVOLT_WARN) { + dev_info(dev, "Undervoltage Warning\n"); + event = REGULATOR_EVENT_UNDER_VOLTAGE; + for (i = 0; i < LTC3676_NUM_REGULATORS; i++) + regulator_notifier_call_chain(ltc3676->regulators[i], + event, NULL); + } + + /* Clear warning condition */ + regmap_write(ltc3676->regmap, LTC3676_CLIRQ, 0); + + return IRQ_HANDLED; +} + +static int ltc3676_regulator_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct regulator_init_data *init_data = dev_get_platdata(dev); + struct regulator_desc *descs; + struct ltc3676 *ltc3676; + int i, ret; + + ltc3676 = devm_kzalloc(dev, sizeof(*ltc3676), GFP_KERNEL); + if (!ltc3676) + return -ENOMEM; + + i2c_set_clientdata(client, ltc3676); + ltc3676->dev = dev; + + descs = ltc3676->regulator_descs; + memcpy(descs, ltc3676_regulators, sizeof(ltc3676_regulators)); + descs[LTC3676_LDO3].fixed_uV = 1800000; /* LDO3 is fixed 1.8V */ + + ltc3676->regmap = devm_regmap_init_i2c(client, <c3676_regmap_config); + if (IS_ERR(ltc3676->regmap)) { + ret = PTR_ERR(ltc3676->regmap); + dev_err(dev, "failed to initialize regmap: %d\n", ret); + return ret; + } + + for (i = 0; i < LTC3676_NUM_REGULATORS; i++) { + struct regulator_desc *desc = <c3676->regulator_descs[i]; + struct regulator_config config = { }; + + if (init_data) + config.init_data = &init_data[i]; + + config.dev = dev; + config.driver_data = ltc3676; + + ltc3676->regulators[i] = devm_regulator_register(dev, desc, + &config); + if (IS_ERR(ltc3676->regulators[i])) { + ret = PTR_ERR(ltc3676->regulators[i]); + dev_err(dev, "failed to register regulator %s: %d\n", + desc->name, ret); + return ret; + } + } + + regmap_write(ltc3676->regmap, LTC3676_CLIRQ, 0); + if (client->irq) { + ret = devm_request_threaded_irq(dev, client->irq, NULL, + ltc3676_isr, + IRQF_TRIGGER_LOW | IRQF_ONESHOT, + client->name, ltc3676); + if (ret) { + dev_err(dev, "Failed to request IRQ: %d\n", ret); + return ret; + } + } + + return 0; +} + +static const struct i2c_device_id ltc3676_i2c_id[] = { + { "ltc3676" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ltc3676_i2c_id); + +static struct i2c_driver ltc3676_driver = { + .driver = { + .name = DRIVER_NAME, + }, + .probe = ltc3676_regulator_probe, + .id_table = ltc3676_i2c_id, +}; +module_i2c_driver(ltc3676_driver); + +MODULE_AUTHOR("Tim Harvey <tharvey@gateworks.com>"); +MODULE_DESCRIPTION("Regulator driver for Linear Technology LTC1376"); +MODULE_LICENSE("GPL v2"); |