// SPDX-License-Identifier: GPL-2.0-or-later // // max20086-regulator.c - MAX20086-MAX20089 camera power protector driver // // Copyright (C) 2022 Laurent Pinchart // Copyright (C) 2018 Avnet, Inc. #include #include #include #include #include #include #include #include #include /* 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 -ENODEV; } 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 = i2c_get_match_data(i2c); 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 max20086_chip_info max20086_chip_info = { .id = MAX20086_DEVICE_ID_MAX20086, .num_outputs = 4, }; static const struct max20086_chip_info max20087_chip_info = { .id = MAX20086_DEVICE_ID_MAX20087, .num_outputs = 4, }; static const struct max20086_chip_info max20088_chip_info = { .id = MAX20086_DEVICE_ID_MAX20088, .num_outputs = 2, }; static const struct max20086_chip_info max20089_chip_info = { .id = MAX20086_DEVICE_ID_MAX20089, .num_outputs = 2, }; static const struct i2c_device_id max20086_i2c_id[] = { { "max20086", (kernel_ulong_t)&max20086_chip_info }, { "max20087", (kernel_ulong_t)&max20087_chip_info }, { "max20088", (kernel_ulong_t)&max20088_chip_info }, { "max20089", (kernel_ulong_t)&max20089_chip_info }, { /* Sentinel */ } }; MODULE_DEVICE_TABLE(i2c, max20086_i2c_id); static const struct of_device_id max20086_dt_ids[] __maybe_unused = { { .compatible = "maxim,max20086", .data = &max20086_chip_info }, { .compatible = "maxim,max20087", .data = &max20087_chip_info }, { .compatible = "maxim,max20088", .data = &max20088_chip_info }, { .compatible = "maxim,max20089", .data = &max20089_chip_info }, { /* Sentinel */ } }; MODULE_DEVICE_TABLE(of, max20086_dt_ids); static struct i2c_driver max20086_regulator_driver = { .driver = { .name = "max20086", .probe_type = PROBE_PREFER_ASYNCHRONOUS, .of_match_table = of_match_ptr(max20086_dt_ids), }, .probe = max20086_i2c_probe, .id_table = max20086_i2c_id, }; module_i2c_driver(max20086_regulator_driver); MODULE_AUTHOR("Watson Chow "); MODULE_DESCRIPTION("MAX20086-MAX20089 Camera Power Protector Driver"); MODULE_LICENSE("GPL");