| // SPDX-License-Identifier: GPL-2.0-or-later |
| // |
| // max20086-regulator.c - MAX20086-MAX20089 camera power protector driver |
| // |
| // Copyright (C) 2022 Laurent Pinchart <laurent.pinchart@idesonboard.com> |
| // Copyright (C) 2018 Avnet, Inc. |
| |
| #include <linux/err.h> |
| #include <linux/gpio.h> |
| #include <linux/i2c.h> |
| #include <linux/module.h> |
| #include <linux/regmap.h> |
| #include <linux/regulator/driver.h> |
| #include <linux/regulator/machine.h> |
| #include <linux/regulator/of_regulator.h> |
| #include <linux/slab.h> |
| |
| /* Register Offset */ |
| #define MAX20086_REG_MASK 0x00 |
| #define MAX20086_REG_CONFIG 0x01 |
| #define MAX20086_REG_ID 0x02 |
| #define MAX20086_REG_STAT1 0x03 |
| #define MAX20086_REG_STAT2_L 0x04 |
| #define MAX20086_REG_STAT2_H 0x05 |
| #define MAX20086_REG_ADC1 0x06 |
| #define MAX20086_REG_ADC2 0x07 |
| #define MAX20086_REG_ADC3 0x08 |
| #define MAX20086_REG_ADC4 0x09 |
| |
| /* DEVICE IDs */ |
| #define MAX20086_DEVICE_ID_MAX20086 0x40 |
| #define MAX20086_DEVICE_ID_MAX20087 0x20 |
| #define MAX20086_DEVICE_ID_MAX20088 0x10 |
| #define MAX20086_DEVICE_ID_MAX20089 0x00 |
| #define DEVICE_ID_MASK 0xf0 |
| |
| /* Register bits */ |
| #define MAX20086_EN_MASK 0x0f |
| #define MAX20086_EN_OUT1 0x01 |
| #define MAX20086_EN_OUT2 0x02 |
| #define MAX20086_EN_OUT3 0x04 |
| #define MAX20086_EN_OUT4 0x08 |
| #define MAX20086_INT_DISABLE_ALL 0x3f |
| |
| #define MAX20086_MAX_REGULATORS 4 |
| |
| struct max20086_chip_info { |
| u8 id; |
| unsigned int num_outputs; |
| }; |
| |
| struct max20086_regulator { |
| struct device_node *of_node; |
| struct regulator_init_data *init_data; |
| const struct regulator_desc *desc; |
| struct regulator_dev *rdev; |
| }; |
| |
| struct max20086 { |
| struct device *dev; |
| struct regmap *regmap; |
| struct gpio_desc *ena_gpiod; |
| |
| const struct max20086_chip_info *info; |
| |
| struct max20086_regulator regulators[MAX20086_MAX_REGULATORS]; |
| }; |
| |
| static const struct regulator_ops max20086_buck_ops = { |
| .enable = regulator_enable_regmap, |
| .disable = regulator_disable_regmap, |
| .is_enabled = regulator_is_enabled_regmap, |
| }; |
| |
| #define MAX20086_REGULATOR_DESC(n) \ |
| { \ |
| .name = "OUT"#n, \ |
| .supply_name = "in", \ |
| .id = (n) - 1, \ |
| .ops = &max20086_buck_ops, \ |
| .type = REGULATOR_VOLTAGE, \ |
| .owner = THIS_MODULE, \ |
| .enable_reg = MAX20086_REG_CONFIG, \ |
| .enable_mask = 1 << ((n) - 1), \ |
| .enable_val = 1 << ((n) - 1), \ |
| .disable_val = 0, \ |
| } |
| |
| static const char * const max20086_output_names[] = { |
| "OUT1", |
| "OUT2", |
| "OUT3", |
| "OUT4", |
| }; |
| |
| static const struct regulator_desc max20086_regulators[] = { |
| MAX20086_REGULATOR_DESC(1), |
| MAX20086_REGULATOR_DESC(2), |
| MAX20086_REGULATOR_DESC(3), |
| MAX20086_REGULATOR_DESC(4), |
| }; |
| |
| static int max20086_regulators_register(struct max20086 *chip) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < chip->info->num_outputs; i++) { |
| struct max20086_regulator *reg = &chip->regulators[i]; |
| struct regulator_config config = { }; |
| struct regulator_dev *rdev; |
| |
| config.dev = chip->dev; |
| config.init_data = reg->init_data; |
| config.driver_data = chip; |
| config.of_node = reg->of_node; |
| config.regmap = chip->regmap; |
| config.ena_gpiod = chip->ena_gpiod; |
| |
| rdev = devm_regulator_register(chip->dev, reg->desc, &config); |
| if (IS_ERR(rdev)) { |
| dev_err(chip->dev, |
| "Failed to register regulator output %s\n", |
| reg->desc->name); |
| return PTR_ERR(rdev); |
| } |
| |
| reg->rdev = rdev; |
| } |
| |
| return 0; |
| } |
| |
| static int max20086_parse_regulators_dt(struct max20086 *chip, bool *boot_on) |
| { |
| struct of_regulator_match matches[MAX20086_MAX_REGULATORS] = { }; |
| struct device_node *node; |
| unsigned int i; |
| int ret; |
| |
| node = of_get_child_by_name(chip->dev->of_node, "regulators"); |
| if (!node) { |
| dev_err(chip->dev, "regulators node not found\n"); |
| return PTR_ERR(node); |
| } |
| |
| for (i = 0; i < chip->info->num_outputs; ++i) |
| matches[i].name = max20086_output_names[i]; |
| |
| ret = of_regulator_match(chip->dev, node, matches, |
| chip->info->num_outputs); |
| of_node_put(node); |
| if (ret < 0) { |
| dev_err(chip->dev, "Failed to match regulators\n"); |
| return -EINVAL; |
| } |
| |
| *boot_on = false; |
| |
| for (i = 0; i < chip->info->num_outputs; i++) { |
| struct max20086_regulator *reg = &chip->regulators[i]; |
| |
| reg->init_data = matches[i].init_data; |
| reg->of_node = matches[i].of_node; |
| reg->desc = &max20086_regulators[i]; |
| |
| if (reg->init_data) { |
| if (reg->init_data->constraints.always_on || |
| reg->init_data->constraints.boot_on) |
| *boot_on = true; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int max20086_detect(struct max20086 *chip) |
| { |
| unsigned int data; |
| int ret; |
| |
| ret = regmap_read(chip->regmap, MAX20086_REG_ID, &data); |
| if (ret < 0) { |
| dev_err(chip->dev, "Failed to read DEVICE_ID reg: %d\n", ret); |
| return ret; |
| } |
| |
| if ((data & DEVICE_ID_MASK) != chip->info->id) { |
| dev_err(chip->dev, "Invalid device ID 0x%02x\n", data); |
| return -ENXIO; |
| } |
| |
| return 0; |
| } |
| |
| static bool max20086_gen_is_writeable_reg(struct device *dev, unsigned int reg) |
| { |
| switch (reg) { |
| case MAX20086_REG_MASK: |
| case MAX20086_REG_CONFIG: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| static const struct regmap_config max20086_regmap_config = { |
| .reg_bits = 8, |
| .val_bits = 8, |
| .writeable_reg = max20086_gen_is_writeable_reg, |
| .max_register = 0x9, |
| .cache_type = REGCACHE_NONE, |
| }; |
| |
| static int max20086_i2c_probe(struct i2c_client *i2c) |
| { |
| struct max20086 *chip; |
| enum gpiod_flags flags; |
| bool boot_on; |
| int ret; |
| |
| chip = devm_kzalloc(&i2c->dev, sizeof(*chip), GFP_KERNEL); |
| if (!chip) |
| return -ENOMEM; |
| |
| chip->dev = &i2c->dev; |
| chip->info = device_get_match_data(chip->dev); |
| |
| i2c_set_clientdata(i2c, chip); |
| |
| chip->regmap = devm_regmap_init_i2c(i2c, &max20086_regmap_config); |
| if (IS_ERR(chip->regmap)) { |
| ret = PTR_ERR(chip->regmap); |
| dev_err(chip->dev, "Failed to allocate register map: %d\n", ret); |
| return ret; |
| } |
| |
| ret = max20086_parse_regulators_dt(chip, &boot_on); |
| if (ret < 0) |
| return ret; |
| |
| ret = max20086_detect(chip); |
| if (ret < 0) |
| return ret; |
| |
| /* Until IRQ support is added, just disable all interrupts. */ |
| ret = regmap_update_bits(chip->regmap, MAX20086_REG_MASK, |
| MAX20086_INT_DISABLE_ALL, |
| MAX20086_INT_DISABLE_ALL); |
| if (ret < 0) { |
| dev_err(chip->dev, "Failed to disable interrupts: %d\n", ret); |
| return ret; |
| } |
| |
| /* |
| * Get the enable GPIO. If any of the outputs is marked as being |
| * enabled at boot, request the GPIO with an initial high state to |
| * avoid disabling outputs that may have been turned on by the boot |
| * loader. Otherwise, request it with a low state to enter lower-power |
| * shutdown. |
| */ |
| flags = boot_on ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW; |
| chip->ena_gpiod = devm_gpiod_get(chip->dev, "enable", flags); |
| if (IS_ERR(chip->ena_gpiod)) { |
| ret = PTR_ERR(chip->ena_gpiod); |
| dev_err(chip->dev, "Failed to get enable GPIO: %d\n", ret); |
| return ret; |
| } |
| |
| ret = max20086_regulators_register(chip); |
| if (ret < 0) { |
| dev_err(chip->dev, "Failed to register regulators: %d\n", ret); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static const struct i2c_device_id max20086_i2c_id[] = { |
| { "max20086" }, |
| { "max20087" }, |
| { "max20088" }, |
| { "max20089" }, |
| { /* Sentinel */ }, |
| }; |
| |
| MODULE_DEVICE_TABLE(i2c, max20086_i2c_id); |
| |
| static const struct of_device_id max20086_dt_ids[] = { |
| { |
| .compatible = "maxim,max20086", |
| .data = &(const struct max20086_chip_info) { |
| .id = MAX20086_DEVICE_ID_MAX20086, |
| .num_outputs = 4, |
| } |
| }, { |
| .compatible = "maxim,max20087", |
| .data = &(const struct max20086_chip_info) { |
| .id = MAX20086_DEVICE_ID_MAX20087, |
| .num_outputs = 4, |
| } |
| }, { |
| .compatible = "maxim,max20088", |
| .data = &(const struct max20086_chip_info) { |
| .id = MAX20086_DEVICE_ID_MAX20088, |
| .num_outputs = 2, |
| } |
| }, { |
| .compatible = "maxim,max20089", |
| .data = &(const struct max20086_chip_info) { |
| .id = MAX20086_DEVICE_ID_MAX20089, |
| .num_outputs = 2, |
| } |
| }, |
| { /* Sentinel */ }, |
| }; |
| |
| MODULE_DEVICE_TABLE(of, max20086_dt_ids); |
| |
| static struct i2c_driver max20086_regulator_driver = { |
| .driver = { |
| .name = "max20086", |
| .of_match_table = of_match_ptr(max20086_dt_ids), |
| }, |
| .probe_new = max20086_i2c_probe, |
| .id_table = max20086_i2c_id, |
| }; |
| |
| module_i2c_driver(max20086_regulator_driver); |
| |
| MODULE_AUTHOR("Watson Chow <watson.chow@avnet.com>"); |
| MODULE_DESCRIPTION("MAX20086-MAX20089 Camera Power Protector Driver"); |
| MODULE_LICENSE("GPL"); |