| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (C) 2016 Gateworks Corporation, Inc. All Rights Reserved. |
| */ |
| #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_DVBxB_PGOOD_MASK 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 int ltc3676_set_voltage_sel(struct regulator_dev *rdev, unsigned selector) |
| { |
| struct ltc3676 *ltc3676 = rdev_get_drvdata(rdev); |
| struct device *dev = ltc3676->dev; |
| int ret, dcdc = rdev_get_id(rdev); |
| |
| dev_dbg(dev, "%s id=%d selector=%d\n", __func__, dcdc, selector); |
| |
| ret = regmap_update_bits(ltc3676->regmap, rdev->desc->vsel_reg + 1, |
| LTC3676_DVBxB_PGOOD_MASK, |
| LTC3676_DVBxB_PGOOD_MASK); |
| if (ret) |
| return ret; |
| |
| return regulator_set_voltage_sel_regmap(rdev, selector); |
| } |
| |
| 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 const 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 = ltc3676_set_voltage_sel, |
| .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 const struct regulator_ops ltc3676_fixed_standby_regulator_ops = { |
| }; |
| |
| /* LDO2, LDO3 fixed (LDO2 has external scalar via R1/R2 feedback res) */ |
| static const 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_readable_writeable_reg(struct device *dev, unsigned int reg) |
| { |
| switch (reg) { |
| case LTC3676_BUCK1 ... LTC3676_IRQSTAT: |
| 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 ... LTC3676_PGSTATRT: |
| return true; |
| } |
| return false; |
| } |
| |
| static const struct regmap_config ltc3676_regmap_config = { |
| .reg_bits = 8, |
| .val_bits = 8, |
| .writeable_reg = ltc3676_readable_writeable_reg, |
| .readable_reg = ltc3676_readable_writeable_reg, |
| .volatile_reg = ltc3676_volatile_reg, |
| .max_register = LTC3676_CLIRQ, |
| .use_single_read = true, |
| .use_single_write = 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_lock(ltc3676->regulators[i]); |
| regulator_notifier_call_chain(ltc3676->regulators[i], |
| event, NULL); |
| regulator_unlock(ltc3676->regulators[i]); |
| } |
| } |
| |
| 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_lock(ltc3676->regulators[i]); |
| regulator_notifier_call_chain(ltc3676->regulators[i], |
| event, NULL); |
| regulator_unlock(ltc3676->regulators[i]); |
| } |
| } |
| |
| /* Clear warning condition */ |
| regmap_write(ltc3676->regmap, LTC3676_CLIRQ, 0); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int ltc3676_regulator_probe(struct i2c_client *client) |
| { |
| 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 const struct of_device_id ltc3676_of_match[] = { |
| { .compatible = "lltc,ltc3676" }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, ltc3676_of_match); |
| |
| static struct i2c_driver ltc3676_driver = { |
| .driver = { |
| .name = DRIVER_NAME, |
| .of_match_table = of_match_ptr(ltc3676_of_match), |
| }, |
| .probe_new = 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 LTC3676"); |
| MODULE_LICENSE("GPL v2"); |
