From 38493f008deb435577361d4c4cdd69f7bb30f4b9 Mon Sep 17 00:00:00 2001 From: Patrick Rudolph Date: Tue, 5 Jul 2022 14:22:41 +0200 Subject: regulator: max597x: Add support for max597x regulator max597x is hot swap controller. This regulator driver controls the same & also configures fault protection features supported by the chip. Signed-off-by: Patrick Rudolph Signed-off-by: Marcello Sylvester Bauer Signed-off-by: Naresh Solanki Link: https://lore.kernel.org/r/20220705122244.472894-4-Naresh.Solanki@9elements.com Signed-off-by: Mark Brown --- drivers/regulator/Kconfig | 10 + drivers/regulator/Makefile | 1 + drivers/regulator/max597x-regulator.c | 506 ++++++++++++++++++++++++++++++++++ 3 files changed, 517 insertions(+) create mode 100644 drivers/regulator/max597x-regulator.c diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig index 03e8a4ef2ed6..aedc4cba9240 100644 --- a/drivers/regulator/Kconfig +++ b/drivers/regulator/Kconfig @@ -546,6 +546,16 @@ config REGULATOR_MAX1586 regulator via I2C bus. The provided regulator is suitable for PXA27x chips to control VCC_CORE and VCC_USIM voltages. +config REGULATOR_MAX597X + tristate "Maxim 597x power switch and monitor" + depends on I2C + depends on OF + select MFD_MAX597X + help + This driver controls a Maxim 5970/5978 switch via I2C bus. + The MAX5970/5978 is a smart switch with no output regulation, but + fault protection and voltage and current monitoring capabilities. + config REGULATOR_MAX77620 tristate "Maxim 77620/MAX20024 voltage regulator" depends on MFD_MAX77620 || COMPILE_TEST diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile index a9c392587120..fa49bb6cc544 100644 --- a/drivers/regulator/Makefile +++ b/drivers/regulator/Makefile @@ -67,6 +67,7 @@ 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-$(CONFIG_REGULATOR_MAX597X) += max597x-regulator.o obj-$(CONFIG_REGULATOR_MAX77620) += max77620-regulator.o obj-$(CONFIG_REGULATOR_MAX77650) += max77650-regulator.o obj-$(CONFIG_REGULATOR_MAX8649) += max8649.o diff --git a/drivers/regulator/max597x-regulator.c b/drivers/regulator/max597x-regulator.c new file mode 100644 index 000000000000..f95acd1c5e3a --- /dev/null +++ b/drivers/regulator/max597x-regulator.c @@ -0,0 +1,506 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Device driver for regulators in MAX5970 and MAX5978 IC + * + * Copyright (c) 2022 9elements GmbH + * + * Author: Patrick Rudolph + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +struct max597x_regulator { + int num_switches, mon_rng, irng, shunt_micro_ohms, lim_uA; + struct regmap *regmap; +}; + +enum max597x_regulator_id { + MAX597X_SW0, + MAX597X_SW1, +}; + +static int max597x_uvp_ovp_check_mode(struct regulator_dev *rdev, int severity) +{ + int ret, reg; + + /* Status1 register contains the soft strap values sampled at POR */ + ret = regmap_read(rdev->regmap, MAX5970_REG_STATUS1, ®); + if (ret) + return ret; + + /* Check soft straps match requested mode */ + if (severity == REGULATOR_SEVERITY_PROT) { + if (STATUS1_PROT(reg) != STATUS1_PROT_SHUTDOWN) + return -EOPNOTSUPP; + + return 0; + } + if (STATUS1_PROT(reg) == STATUS1_PROT_SHUTDOWN) + return -EOPNOTSUPP; + + return 0; +} + +static int max597x_set_vp(struct regulator_dev *rdev, int lim_uV, int severity, + bool enable, bool overvoltage) +{ + int off_h, off_l, reg, ret; + struct max597x_regulator *data = rdev_get_drvdata(rdev); + int channel = rdev_get_id(rdev); + + if (overvoltage) { + if (severity == REGULATOR_SEVERITY_WARN) { + off_h = MAX5970_REG_CH_OV_WARN_H(channel); + off_l = MAX5970_REG_CH_OV_WARN_L(channel); + } else { + off_h = MAX5970_REG_CH_OV_CRIT_H(channel); + off_l = MAX5970_REG_CH_OV_CRIT_L(channel); + } + } else { + if (severity == REGULATOR_SEVERITY_WARN) { + off_h = MAX5970_REG_CH_UV_WARN_H(channel); + off_l = MAX5970_REG_CH_UV_WARN_L(channel); + } else { + off_h = MAX5970_REG_CH_UV_CRIT_H(channel); + off_l = MAX5970_REG_CH_UV_CRIT_L(channel); + } + } + + if (enable) + /* reg = ADC_MASK * (lim_uV / 1000000) / (data->mon_rng / 1000000) */ + reg = ADC_MASK * lim_uV / data->mon_rng; + else + reg = 0; + + ret = regmap_write(rdev->regmap, off_h, MAX5970_VAL2REG_H(reg)); + if (ret) + return ret; + + ret = regmap_write(rdev->regmap, off_l, MAX5970_VAL2REG_L(reg)); + if (ret) + return ret; + + return 0; +} + +static int max597x_set_uvp(struct regulator_dev *rdev, int lim_uV, int severity, + bool enable) +{ + int ret; + + /* + * MAX5970 has enable control as a special value in limit reg. Can't + * set limit but keep feature disabled or enable W/O given limit. + */ + if ((lim_uV && !enable) || (!lim_uV && enable)) + return -EINVAL; + + ret = max597x_uvp_ovp_check_mode(rdev, severity); + if (ret) + return ret; + + return max597x_set_vp(rdev, lim_uV, severity, enable, false); +} + +static int max597x_set_ovp(struct regulator_dev *rdev, int lim_uV, int severity, + bool enable) +{ + int ret; + + /* + * MAX5970 has enable control as a special value in limit reg. Can't + * set limit but keep feature disabled or enable W/O given limit. + */ + if ((lim_uV && !enable) || (!lim_uV && enable)) + return -EINVAL; + + ret = max597x_uvp_ovp_check_mode(rdev, severity); + if (ret) + return ret; + + return max597x_set_vp(rdev, lim_uV, severity, enable, true); +} + +static int max597x_set_ocp(struct regulator_dev *rdev, int lim_uA, + int severity, bool enable) +{ + int ret, val, reg; + unsigned int vthst, vthfst; + + struct max597x_regulator *data = rdev_get_drvdata(rdev); + int rdev_id = rdev_get_id(rdev); + /* + * MAX5970 doesn't has enable control for ocp. + * If limit is specified but enable is not set then hold the value in + * variable & later use it when ocp needs to be enabled. + */ + if (lim_uA != 0 && lim_uA != data->lim_uA) + data->lim_uA = lim_uA; + + if (severity != REGULATOR_SEVERITY_PROT) + return -EINVAL; + + if (enable) { + + /* Calc Vtrip threshold in uV. */ + vthst = + div_u64(mul_u32_u32(data->shunt_micro_ohms, data->lim_uA), + 1000000); + + /* + * As recommended in datasheed, add 20% margin to avoid + * spurious event & passive component tolerance. + */ + vthst = div_u64(mul_u32_u32(vthst, 120), 100); + + /* Calc fast Vtrip threshold in uV */ + vthfst = vthst * (MAX5970_FAST2SLOW_RATIO / 100); + + if (vthfst > data->irng) { + dev_err(&rdev->dev, "Current limit out of range\n"); + return -EINVAL; + } + /* Fast trip threshold to be programmed */ + val = div_u64(mul_u32_u32(0xFF, vthfst), data->irng); + } else + /* + * Since there is no option to disable ocp, set limit to max + * value + */ + val = 0xFF; + + reg = MAX5970_REG_DAC_FAST(rdev_id); + ret = regmap_write(rdev->regmap, reg, val); + + return ret; +} + +static int max597x_get_status(struct regulator_dev *rdev) +{ + int val, ret; + + ret = regmap_read(rdev->regmap, MAX5970_REG_STATUS3, &val); + if (ret) + return REGULATOR_FAILED_RETRY; + + if (val & MAX5970_STATUS3_ALERT) + return REGULATOR_STATUS_ERROR; + + ret = regulator_is_enabled_regmap(rdev); + if (ret < 0) + return ret; + + if (ret) + return REGULATOR_STATUS_ON; + + return REGULATOR_STATUS_OFF; +} + +static const struct regulator_ops max597x_switch_ops = { + .enable = regulator_enable_regmap, + .disable = regulator_disable_regmap, + .is_enabled = regulator_is_enabled_regmap, + .get_status = max597x_get_status, + .set_over_voltage_protection = max597x_set_ovp, + .set_under_voltage_protection = max597x_set_uvp, + .set_over_current_protection = max597x_set_ocp, +}; + +static int max597x_dt_parse(struct device_node *np, + const struct regulator_desc *desc, + struct regulator_config *cfg) +{ + struct max597x_regulator *data = cfg->driver_data; + int ret = 0; + + ret = + of_property_read_u32(np, "shunt-resistor-micro-ohms", + &data->shunt_micro_ohms); + if (ret < 0) + dev_err(cfg->dev, + "property 'shunt-resistor-micro-ohms' not found, err %d\n", + ret); + return ret; + +} + +#define MAX597X_SWITCH(_ID, _ereg, _chan, _supply) { \ + .name = #_ID, \ + .of_match = of_match_ptr(#_ID), \ + .ops = &max597x_switch_ops, \ + .regulators_node = of_match_ptr("regulators"), \ + .type = REGULATOR_VOLTAGE, \ + .id = MAX597X_##_ID, \ + .owner = THIS_MODULE, \ + .supply_name = _supply, \ + .enable_reg = _ereg, \ + .enable_mask = CHXEN((_chan)), \ + .of_parse_cb = max597x_dt_parse, \ +} + +static const struct regulator_desc regulators[] = { + MAX597X_SWITCH(SW0, MAX5970_REG_CHXEN, 0, "vss1"), + MAX597X_SWITCH(SW1, MAX5970_REG_CHXEN, 1, "vss2"), +}; + +static int max597x_regmap_read_clear(struct regmap *map, unsigned int reg, + unsigned int *val) +{ + int ret; + + ret = regmap_read(map, reg, val); + if (ret) + return ret; + + if (*val) + return regmap_write(map, reg, *val); + + return 0; +} + +static int max597x_irq_handler(int irq, struct regulator_irq_data *rid, + unsigned long *dev_mask) +{ + struct regulator_err_state *stat; + struct max597x_regulator *d = (struct max597x_regulator *)rid->data; + int val, ret, i; + + ret = max597x_regmap_read_clear(d->regmap, MAX5970_REG_FAULT0, &val); + if (ret) + return REGULATOR_FAILED_RETRY; + + *dev_mask = 0; + for (i = 0; i < d->num_switches; i++) { + stat = &rid->states[i]; + stat->notifs = 0; + stat->errors = 0; + } + + for (i = 0; i < d->num_switches; i++) { + stat = &rid->states[i]; + + if (val & UV_STATUS_CRIT(i)) { + *dev_mask |= 1 << i; + stat->notifs |= REGULATOR_EVENT_UNDER_VOLTAGE; + stat->errors |= REGULATOR_ERROR_UNDER_VOLTAGE; + } else if (val & UV_STATUS_WARN(i)) { + *dev_mask |= 1 << i; + stat->notifs |= REGULATOR_EVENT_UNDER_VOLTAGE_WARN; + stat->errors |= REGULATOR_ERROR_UNDER_VOLTAGE_WARN; + } + } + + ret = max597x_regmap_read_clear(d->regmap, MAX5970_REG_FAULT1, &val); + if (ret) + return REGULATOR_FAILED_RETRY; + + for (i = 0; i < d->num_switches; i++) { + stat = &rid->states[i]; + + if (val & OV_STATUS_CRIT(i)) { + *dev_mask |= 1 << i; + stat->notifs |= REGULATOR_EVENT_REGULATION_OUT; + stat->errors |= REGULATOR_ERROR_REGULATION_OUT; + } else if (val & OV_STATUS_WARN(i)) { + *dev_mask |= 1 << i; + stat->notifs |= REGULATOR_EVENT_OVER_VOLTAGE_WARN; + stat->errors |= REGULATOR_ERROR_OVER_VOLTAGE_WARN; + } + } + + ret = max597x_regmap_read_clear(d->regmap, MAX5970_REG_FAULT2, &val); + if (ret) + return REGULATOR_FAILED_RETRY; + + for (i = 0; i < d->num_switches; i++) { + stat = &rid->states[i]; + + if (val & OC_STATUS_WARN(i)) { + *dev_mask |= 1 << i; + stat->notifs |= REGULATOR_EVENT_OVER_CURRENT_WARN; + stat->errors |= REGULATOR_ERROR_OVER_CURRENT_WARN; + } + } + + ret = regmap_read(d->regmap, MAX5970_REG_STATUS0, &val); + if (ret) + return REGULATOR_FAILED_RETRY; + + for (i = 0; i < d->num_switches; i++) { + stat = &rid->states[i]; + + if ((val & MAX5970_CB_IFAULTF(i)) + || (val & MAX5970_CB_IFAULTS(i))) { + *dev_mask |= 1 << i; + stat->notifs |= + REGULATOR_EVENT_OVER_CURRENT | + REGULATOR_EVENT_DISABLE; + stat->errors |= + REGULATOR_ERROR_OVER_CURRENT | REGULATOR_ERROR_FAIL; + + /* Clear the sub-IRQ status */ + regulator_disable_regmap(stat->rdev); + } + } + return 0; +} + +static const struct regmap_config max597x_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = MAX_REGISTERS, +}; + +static int max597x_adc_range(struct regmap *regmap, const int ch, + u32 *irng, u32 *mon_rng) +{ + unsigned int reg; + int ret; + + /* Decode current ADC range */ + ret = regmap_read(regmap, MAX5970_REG_STATUS2, ®); + if (ret) + return ret; + switch (MAX5970_IRNG(reg, ch)) { + case 0: + *irng = 100000; /* 100 mV */ + break; + case 1: + *irng = 50000; /* 50 mV */ + break; + case 2: + *irng = 25000; /* 25 mV */ + break; + default: + return -EINVAL; + } + + /* Decode current voltage monitor range */ + ret = regmap_read(regmap, MAX5970_REG_MON_RANGE, ®); + if (ret) + return ret; + + *mon_rng = MAX5970_MON_MAX_RANGE_UV >> MAX5970_MON(reg, ch); + + return 0; +} + +static int max597x_setup_irq(struct device *dev, + int irq, + struct regulator_dev *rdevs[MAX5970_NUM_SWITCHES], + int num_switches, struct max597x_regulator *data) +{ + struct regulator_irq_desc max597x_notif = { + .name = "max597x-irq", + .map_event = max597x_irq_handler, + .data = data, + }; + int errs = REGULATOR_ERROR_UNDER_VOLTAGE | + REGULATOR_ERROR_UNDER_VOLTAGE_WARN | + REGULATOR_ERROR_OVER_VOLTAGE_WARN | + REGULATOR_ERROR_REGULATION_OUT | + REGULATOR_ERROR_OVER_CURRENT | + REGULATOR_ERROR_OVER_CURRENT_WARN | REGULATOR_ERROR_FAIL; + void *irq_helper; + + /* Register notifiers - can fail if IRQ is not given */ + irq_helper = devm_regulator_irq_helper(dev, &max597x_notif, + irq, 0, errs, NULL, + &rdevs[0], num_switches); + if (IS_ERR(irq_helper)) { + if (PTR_ERR(irq_helper) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + dev_warn(dev, "IRQ disabled %pe\n", irq_helper); + } + + return 0; +} + +static int max597x_regulator_probe(struct platform_device *pdev) +{ + + + struct max597x_data *max597x = dev_get_drvdata(pdev->dev.parent); + struct max597x_regulator *data; + + struct regulator_config config = { }; + struct regulator_dev *rdev; + struct regulator_dev *rdevs[MAX5970_NUM_SWITCHES]; + int num_switches = max597x->num_switches; + int ret, i; + + for (i = 0; i < num_switches; i++) { + data = + devm_kzalloc(max597x->dev, sizeof(struct max597x_regulator), + GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->num_switches = num_switches; + data->regmap = max597x->regmap; + + if (ret < 0) + return ret; + + ret = max597x_adc_range(data->regmap, i, &max597x->irng[i], &max597x->mon_rng[i]); + if (ret < 0) + return ret; + + data->irng = max597x->irng[i]; + data->mon_rng = max597x->mon_rng[i]; + + config.dev = max597x->dev; + config.driver_data = (void *)data; + config.regmap = data->regmap; + rdev = devm_regulator_register(max597x->dev, + ®ulators[i], &config); + if (IS_ERR(rdev)) { + dev_err(max597x->dev, "failed to register regulator %s\n", + regulators[i].name); + return PTR_ERR(rdev); + } + rdevs[i] = rdev; + max597x->shunt_micro_ohms[i] = data->shunt_micro_ohms; + } + + if (max597x->irq) { + ret = + max597x_setup_irq(max597x->dev, max597x->irq, rdevs, num_switches, + data); + if (ret) { + dev_err(max597x->dev, "IRQ setup failed"); + return ret; + } + } + + return ret; +} + +static struct platform_driver max597x_regulator_driver = { + .driver = { + .name = "max597x-regulator", + }, + .probe = max597x_regulator_probe, +}; + +module_platform_driver(max597x_regulator_driver); + + +MODULE_AUTHOR("Patrick Rudolph "); +MODULE_DESCRIPTION("MAX5970_hot-swap controller driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3-59-g8ed1b