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Diffstat (limited to 'drivers/regulator/mcp16502.c')
| -rw-r--r-- | drivers/regulator/mcp16502.c | 520 |
1 files changed, 520 insertions, 0 deletions
diff --git a/drivers/regulator/mcp16502.c b/drivers/regulator/mcp16502.c new file mode 100644 index 000000000000..7cbc96f7afcf --- /dev/null +++ b/drivers/regulator/mcp16502.c @@ -0,0 +1,520 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// MCP16502 PMIC driver +// +// Copyright (C) 2018 Microchip Technology Inc. and its subsidiaries +// +// Author: Andrei Stefanescu <andrei.stefanescu@microchip.com> +// +// Inspired from tps65086-regulator.c + +#include <linux/gpio.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/regmap.h> +#include <linux/regulator/driver.h> +#include <linux/suspend.h> + +#define VDD_LOW_SEL 0x0D +#define VDD_HIGH_SEL 0x3F + +#define MCP16502_FLT BIT(7) +#define MCP16502_ENS BIT(0) + +/* + * The PMIC has four sets of registers corresponding to four power modes: + * Performance, Active, Low-power, Hibernate. + * + * Registers: + * Each regulator has a register for each power mode. To access a register + * for a specific regulator and mode BASE_* and OFFSET_* need to be added. + * + * Operating modes: + * In order for the PMIC to transition to operating modes it has to be + * controlled via GPIO lines called LPM and HPM. + * + * The registers are fully configurable such that you can put all regulators in + * a low-power state while the PMIC is in Active mode. They are supposed to be + * configured at startup and then simply transition to/from a global low-power + * state by setting the GPIO lpm pin high/low. + * + * This driver keeps the PMIC in Active mode, Low-power state is set for the + * regulators by enabling/disabling operating mode (FPWM or Auto PFM). + * + * The PMIC's Low-power and Hibernate modes are used during standby/suspend. + * To enter standby/suspend the PMIC will go to Low-power mode. From there, it + * will transition to Hibernate when the PWRHLD line is set to low by the MPU. + */ + +/* + * This function is useful for iterating over all regulators and accessing their + * registers in a generic way or accessing a regulator device by its id. + */ +#define MCP16502_BASE(i) (((i) + 1) << 4) +#define MCP16502_STAT_BASE(i) ((i) + 5) + +#define MCP16502_OFFSET_MODE_A 0 +#define MCP16502_OFFSET_MODE_LPM 1 +#define MCP16502_OFFSET_MODE_HIB 2 + +#define MCP16502_OPMODE_ACTIVE REGULATOR_MODE_NORMAL +#define MCP16502_OPMODE_LPM REGULATOR_MODE_IDLE +#define MCP16502_OPMODE_HIB REGULATOR_MODE_STANDBY + +#define MCP16502_MODE_AUTO_PFM 0 +#define MCP16502_MODE_FPWM BIT(6) + +#define MCP16502_VSEL 0x3F +#define MCP16502_EN BIT(7) +#define MCP16502_MODE BIT(6) + +#define MCP16502_MIN_REG 0x0 +#define MCP16502_MAX_REG 0x65 + +static unsigned int mcp16502_of_map_mode(unsigned int mode) +{ + if (mode == REGULATOR_MODE_NORMAL || mode == REGULATOR_MODE_IDLE) + return mode; + + return REGULATOR_MODE_INVALID; +} + +#define MCP16502_REGULATOR(_name, _id, _ranges, _ops) \ + [_id] = { \ + .name = _name, \ + .regulators_node = of_match_ptr("regulators"), \ + .id = _id, \ + .ops = &(_ops), \ + .type = REGULATOR_VOLTAGE, \ + .owner = THIS_MODULE, \ + .linear_ranges = _ranges, \ + .n_linear_ranges = ARRAY_SIZE(_ranges), \ + .of_match = of_match_ptr(_name), \ + .of_map_mode = mcp16502_of_map_mode, \ + .vsel_reg = (((_id) + 1) << 4), \ + .vsel_mask = MCP16502_VSEL, \ + .enable_reg = (((_id) + 1) << 4), \ + .enable_mask = MCP16502_EN, \ + } + +enum { + BUCK1 = 0, + BUCK2, + BUCK3, + BUCK4, + LDO1, + LDO2, + NUM_REGULATORS +}; + +/* + * struct mcp16502 - PMIC representation + * @rdev: the regulators belonging to this chip + * @rmap: regmap to be used for I2C communication + * @lpm: LPM GPIO descriptor + */ +struct mcp16502 { + struct regulator_dev *rdev[NUM_REGULATORS]; + struct regmap *rmap; + struct gpio_desc *lpm; +}; + +/* + * mcp16502_gpio_set_mode() - set the GPIO corresponding value + * + * Used to prepare transitioning into hibernate or resuming from it. + */ +static void mcp16502_gpio_set_mode(struct mcp16502 *mcp, int mode) +{ + switch (mode) { + case MCP16502_OPMODE_ACTIVE: + gpiod_set_value(mcp->lpm, 0); + break; + case MCP16502_OPMODE_LPM: + case MCP16502_OPMODE_HIB: + gpiod_set_value(mcp->lpm, 1); + break; + default: + pr_err("%s: %d invalid\n", __func__, mode); + } +} + +/* + * mcp16502_get_reg() - get the PMIC's configuration register for opmode + * + * @rdev: the regulator whose register we are searching + * @opmode: the PMIC's operating mode ACTIVE, Low-power, Hibernate + */ +static int mcp16502_get_reg(struct regulator_dev *rdev, int opmode) +{ + int reg = MCP16502_BASE(rdev_get_id(rdev)); + + switch (opmode) { + case MCP16502_OPMODE_ACTIVE: + return reg + MCP16502_OFFSET_MODE_A; + case MCP16502_OPMODE_LPM: + return reg + MCP16502_OFFSET_MODE_LPM; + case MCP16502_OPMODE_HIB: + return reg + MCP16502_OFFSET_MODE_HIB; + default: + return -EINVAL; + } +} + +/* + * mcp16502_get_mode() - return the current operating mode of a regulator + * + * Note: all functions that are not part of entering/exiting standby/suspend + * use the Active mode registers. + * + * Note: this is different from the PMIC's operatig mode, it is the + * MODE bit from the regulator's register. + */ +static unsigned int mcp16502_get_mode(struct regulator_dev *rdev) +{ + unsigned int val; + int ret, reg; + struct mcp16502 *mcp = rdev_get_drvdata(rdev); + + reg = mcp16502_get_reg(rdev, MCP16502_OPMODE_ACTIVE); + if (reg < 0) + return reg; + + ret = regmap_read(mcp->rmap, reg, &val); + if (ret) + return ret; + + switch (val & MCP16502_MODE) { + case MCP16502_MODE_FPWM: + return REGULATOR_MODE_NORMAL; + case MCP16502_MODE_AUTO_PFM: + return REGULATOR_MODE_IDLE; + default: + return REGULATOR_MODE_INVALID; + } +} + +/* + * _mcp16502_set_mode() - helper for set_mode and set_suspend_mode + * + * @rdev: the regulator for which we are setting the mode + * @mode: the regulator's mode (the one from MODE bit) + * @opmode: the PMIC's operating mode: Active/Low-power/Hibernate + */ +static int _mcp16502_set_mode(struct regulator_dev *rdev, unsigned int mode, + unsigned int op_mode) +{ + int val; + int reg; + struct mcp16502 *mcp = rdev_get_drvdata(rdev); + + reg = mcp16502_get_reg(rdev, op_mode); + if (reg < 0) + return reg; + + switch (mode) { + case REGULATOR_MODE_NORMAL: + val = MCP16502_MODE_FPWM; + break; + case REGULATOR_MODE_IDLE: + val = MCP16502_MODE_AUTO_PFM; + break; + default: + return -EINVAL; + } + + reg = regmap_update_bits(mcp->rmap, reg, MCP16502_MODE, val); + return reg; +} + +/* + * mcp16502_set_mode() - regulator_ops set_mode + */ +static int mcp16502_set_mode(struct regulator_dev *rdev, unsigned int mode) +{ + return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_ACTIVE); +} + +/* + * mcp16502_get_status() - regulator_ops get_status + */ +static int mcp16502_get_status(struct regulator_dev *rdev) +{ + int ret; + unsigned int val; + struct mcp16502 *mcp = rdev_get_drvdata(rdev); + + ret = regmap_read(mcp->rmap, MCP16502_STAT_BASE(rdev_get_id(rdev)), + &val); + if (ret) + return ret; + + if (val & MCP16502_FLT) + return REGULATOR_STATUS_ERROR; + else if (val & MCP16502_ENS) + return REGULATOR_STATUS_ON; + else if (!(val & MCP16502_ENS)) + return REGULATOR_STATUS_OFF; + + return REGULATOR_STATUS_UNDEFINED; +} + +#ifdef CONFIG_SUSPEND +/* + * mcp16502_suspend_get_target_reg() - get the reg of the target suspend PMIC + * mode + */ +static int mcp16502_suspend_get_target_reg(struct regulator_dev *rdev) +{ + switch (pm_suspend_target_state) { + case PM_SUSPEND_STANDBY: + return mcp16502_get_reg(rdev, MCP16502_OPMODE_LPM); + case PM_SUSPEND_ON: + case PM_SUSPEND_MEM: + return mcp16502_get_reg(rdev, MCP16502_OPMODE_HIB); + default: + dev_err(&rdev->dev, "invalid suspend target: %d\n", + pm_suspend_target_state); + } + + return -EINVAL; +} + +/* + * mcp16502_set_suspend_voltage() - regulator_ops set_suspend_voltage + */ +static int mcp16502_set_suspend_voltage(struct regulator_dev *rdev, int uV) +{ + struct mcp16502 *mcp = rdev_get_drvdata(rdev); + int sel = regulator_map_voltage_linear_range(rdev, uV, uV); + int reg = mcp16502_suspend_get_target_reg(rdev); + + if (sel < 0) + return sel; + + if (reg < 0) + return reg; + + return regmap_update_bits(mcp->rmap, reg, MCP16502_VSEL, sel); +} + +/* + * mcp16502_set_suspend_mode() - regulator_ops set_suspend_mode + */ +static int mcp16502_set_suspend_mode(struct regulator_dev *rdev, + unsigned int mode) +{ + switch (pm_suspend_target_state) { + case PM_SUSPEND_STANDBY: + return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_LPM); + case PM_SUSPEND_ON: + case PM_SUSPEND_MEM: + return _mcp16502_set_mode(rdev, mode, MCP16502_OPMODE_HIB); + default: + dev_err(&rdev->dev, "invalid suspend target: %d\n", + pm_suspend_target_state); + } + + return -EINVAL; +} + +/* + * mcp16502_set_suspend_enable() - regulator_ops set_suspend_enable + */ +static int mcp16502_set_suspend_enable(struct regulator_dev *rdev) +{ + struct mcp16502 *mcp = rdev_get_drvdata(rdev); + int reg = mcp16502_suspend_get_target_reg(rdev); + + if (reg < 0) + return reg; + + return regmap_update_bits(mcp->rmap, reg, MCP16502_EN, MCP16502_EN); +} + +/* + * mcp16502_set_suspend_disable() - regulator_ops set_suspend_disable + */ +static int mcp16502_set_suspend_disable(struct regulator_dev *rdev) +{ + struct mcp16502 *mcp = rdev_get_drvdata(rdev); + int reg = mcp16502_suspend_get_target_reg(rdev); + + if (reg < 0) + return reg; + + return regmap_update_bits(mcp->rmap, reg, MCP16502_EN, 0); +} +#endif /* CONFIG_SUSPEND */ + +static const struct regulator_ops mcp16502_buck_ops = { + .list_voltage = regulator_list_voltage_linear_range, + .map_voltage = regulator_map_voltage_linear_range, + .get_voltage_sel = regulator_get_voltage_sel_regmap, + .set_voltage_sel = regulator_set_voltage_sel_regmap, + .enable = regulator_enable_regmap, + .disable = regulator_disable_regmap, + .is_enabled = regulator_is_enabled_regmap, + .get_status = mcp16502_get_status, + + .set_mode = mcp16502_set_mode, + .get_mode = mcp16502_get_mode, + +#ifdef CONFIG_SUSPEND + .set_suspend_voltage = mcp16502_set_suspend_voltage, + .set_suspend_mode = mcp16502_set_suspend_mode, + .set_suspend_enable = mcp16502_set_suspend_enable, + .set_suspend_disable = mcp16502_set_suspend_disable, +#endif /* CONFIG_SUSPEND */ +}; + +/* + * LDOs cannot change operating modes. + */ +static const struct regulator_ops mcp16502_ldo_ops = { + .list_voltage = regulator_list_voltage_linear_range, + .map_voltage = regulator_map_voltage_linear_range, + .get_voltage_sel = regulator_get_voltage_sel_regmap, + .set_voltage_sel = regulator_set_voltage_sel_regmap, + .enable = regulator_enable_regmap, + .disable = regulator_disable_regmap, + .is_enabled = regulator_is_enabled_regmap, + .get_status = mcp16502_get_status, + +#ifdef CONFIG_SUSPEND + .set_suspend_voltage = mcp16502_set_suspend_voltage, + .set_suspend_enable = mcp16502_set_suspend_enable, + .set_suspend_disable = mcp16502_set_suspend_disable, +#endif /* CONFIG_SUSPEND */ +}; + +static const struct of_device_id mcp16502_ids[] = { + { .compatible = "microchip,mcp16502", }, + {} +}; +MODULE_DEVICE_TABLE(of, mcp16502_ids); + +static const struct regulator_linear_range b1l12_ranges[] = { + REGULATOR_LINEAR_RANGE(1200000, VDD_LOW_SEL, VDD_HIGH_SEL, 50000), +}; + +static const struct regulator_linear_range b234_ranges[] = { + REGULATOR_LINEAR_RANGE(600000, VDD_LOW_SEL, VDD_HIGH_SEL, 25000), +}; + +static const struct regulator_desc mcp16502_desc[] = { + /* MCP16502_REGULATOR(_name, _id, ranges, regulator_ops) */ + MCP16502_REGULATOR("VDD_IO", BUCK1, b1l12_ranges, mcp16502_buck_ops), + MCP16502_REGULATOR("VDD_DDR", BUCK2, b234_ranges, mcp16502_buck_ops), + MCP16502_REGULATOR("VDD_CORE", BUCK3, b234_ranges, mcp16502_buck_ops), + MCP16502_REGULATOR("VDD_OTHER", BUCK4, b234_ranges, mcp16502_buck_ops), + MCP16502_REGULATOR("LDO1", LDO1, b1l12_ranges, mcp16502_ldo_ops), + MCP16502_REGULATOR("LDO2", LDO2, b1l12_ranges, mcp16502_ldo_ops) +}; + +static const struct regmap_range mcp16502_ranges[] = { + regmap_reg_range(MCP16502_MIN_REG, MCP16502_MAX_REG) +}; + +static const struct regmap_access_table mcp16502_yes_reg_table = { + .yes_ranges = mcp16502_ranges, + .n_yes_ranges = ARRAY_SIZE(mcp16502_ranges), +}; + +static const struct regmap_config mcp16502_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = MCP16502_MAX_REG, + .cache_type = REGCACHE_NONE, + .rd_table = &mcp16502_yes_reg_table, + .wr_table = &mcp16502_yes_reg_table, +}; + +/* + * set_up_regulators() - initialize all regulators + */ +static int setup_regulators(struct mcp16502 *mcp, struct device *dev, + struct regulator_config config) +{ + int i; + + for (i = 0; i < NUM_REGULATORS; i++) { + mcp->rdev[i] = devm_regulator_register(dev, + &mcp16502_desc[i], + &config); + if (IS_ERR(mcp->rdev[i])) { + dev_err(dev, + "failed to register %s regulator %ld\n", + mcp16502_desc[i].name, PTR_ERR(mcp->rdev[i])); + return PTR_ERR(mcp->rdev[i]); + } + } + + return 0; +} + +static int mcp16502_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct regulator_config config = { }; + struct device *dev; + struct mcp16502 *mcp; + int ret = 0; + + dev = &client->dev; + config.dev = dev; + + mcp = devm_kzalloc(dev, sizeof(*mcp), GFP_KERNEL); + if (!mcp) + return -ENOMEM; + + mcp->rmap = devm_regmap_init_i2c(client, &mcp16502_regmap_config); + if (IS_ERR(mcp->rmap)) { + ret = PTR_ERR(mcp->rmap); + dev_err(dev, "regmap init failed: %d\n", ret); + return ret; + } + + i2c_set_clientdata(client, mcp); + config.regmap = mcp->rmap; + config.driver_data = mcp; + + mcp->lpm = devm_gpiod_get(dev, "lpm", GPIOD_OUT_LOW); + if (IS_ERR(mcp->lpm)) { + dev_err(dev, "failed to get lpm pin: %ld\n", PTR_ERR(mcp->lpm)); + return PTR_ERR(mcp->lpm); + } + + ret = setup_regulators(mcp, dev, config); + if (ret != 0) + return ret; + + mcp16502_gpio_set_mode(mcp, MCP16502_OPMODE_ACTIVE); + + return 0; +} + +static const struct i2c_device_id mcp16502_i2c_id[] = { + { "mcp16502", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, mcp16502_i2c_id); + +static struct i2c_driver mcp16502_drv = { + .probe = mcp16502_probe, + .driver = { + .name = "mcp16502-regulator", + .of_match_table = of_match_ptr(mcp16502_ids), + }, + .id_table = mcp16502_i2c_id, +}; + +module_i2c_driver(mcp16502_drv); + +MODULE_VERSION("1.0"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("MCP16502 PMIC driver"); +MODULE_AUTHOR("Andrei Stefanescu andrei.stefanescu@microchip.com"); |