--- /dev/null
+// 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");
projects / openwrt / staging / blogic.git / commitdiff