diff options
Diffstat (limited to 'drivers/mfd/max77714.c')
| -rw-r--r-- | drivers/mfd/max77714.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/mfd/max77714.c b/drivers/mfd/max77714.c new file mode 100644 index 000000000000..d1e4247800d2 --- /dev/null +++ b/drivers/mfd/max77714.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Maxim MAX77714 Core Driver + * + * Copyright (C) 2022 Luca Ceresoli + * Author: Luca Ceresoli <luca@lucaceresoli.net> + */ + +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/mfd/core.h> +#include <linux/mfd/max77714.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/regmap.h> + +static const struct mfd_cell max77714_cells[] = { + { .name = "max77714-watchdog" }, + { .name = "max77714-rtc" }, +}; + +static const struct regmap_range max77714_readable_ranges[] = { + regmap_reg_range(MAX77714_INT_TOP, MAX77714_INT_TOP), + regmap_reg_range(MAX77714_INT_TOPM, MAX77714_INT_TOPM), + regmap_reg_range(MAX77714_32K_STATUS, MAX77714_32K_CONFIG), + regmap_reg_range(MAX77714_CNFG_GLBL2, MAX77714_CNFG2_ONOFF), +}; + +static const struct regmap_range max77714_writable_ranges[] = { + regmap_reg_range(MAX77714_INT_TOPM, MAX77714_INT_TOPM), + regmap_reg_range(MAX77714_32K_CONFIG, MAX77714_32K_CONFIG), + regmap_reg_range(MAX77714_CNFG_GLBL2, MAX77714_CNFG2_ONOFF), +}; + +static const struct regmap_access_table max77714_readable_table = { + .yes_ranges = max77714_readable_ranges, + .n_yes_ranges = ARRAY_SIZE(max77714_readable_ranges), +}; + +static const struct regmap_access_table max77714_writable_table = { + .yes_ranges = max77714_writable_ranges, + .n_yes_ranges = ARRAY_SIZE(max77714_writable_ranges), +}; + +static const struct regmap_config max77714_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = MAX77714_CNFG2_ONOFF, + .rd_table = &max77714_readable_table, + .wr_table = &max77714_writable_table, +}; + +static const struct regmap_irq max77714_top_irqs[] = { + REGMAP_IRQ_REG(MAX77714_IRQ_TOP_ONOFF, 0, MAX77714_INT_TOP_ONOFF), + REGMAP_IRQ_REG(MAX77714_IRQ_TOP_RTC, 0, MAX77714_INT_TOP_RTC), + REGMAP_IRQ_REG(MAX77714_IRQ_TOP_GPIO, 0, MAX77714_INT_TOP_GPIO), + REGMAP_IRQ_REG(MAX77714_IRQ_TOP_LDO, 0, MAX77714_INT_TOP_LDO), + REGMAP_IRQ_REG(MAX77714_IRQ_TOP_SD, 0, MAX77714_INT_TOP_SD), + REGMAP_IRQ_REG(MAX77714_IRQ_TOP_GLBL, 0, MAX77714_INT_TOP_GLBL), +}; + +static const struct regmap_irq_chip max77714_irq_chip = { + .name = "max77714-pmic", + .status_base = MAX77714_INT_TOP, + .mask_base = MAX77714_INT_TOPM, + .num_regs = 1, + .irqs = max77714_top_irqs, + .num_irqs = ARRAY_SIZE(max77714_top_irqs), +}; + +/* + * MAX77714 initially uses the internal, low precision oscillator. Enable + * the external oscillator by setting the XOSC_RETRY bit. If the external + * oscillator is not OK (probably not installed) this has no effect. + */ +static int max77714_setup_xosc(struct device *dev, struct regmap *regmap) +{ + /* Internal Crystal Load Capacitance, indexed by value of 32KLOAD bits */ + static const unsigned int load_cap[4] = {0, 10, 12, 22}; /* pF */ + unsigned int load_cap_idx; + unsigned int status; + int err; + + err = regmap_update_bits(regmap, MAX77714_32K_CONFIG, + MAX77714_32K_CONFIG_XOSC_RETRY, + MAX77714_32K_CONFIG_XOSC_RETRY); + if (err) + return dev_err_probe(dev, err, "Failed to configure the external oscillator\n"); + + err = regmap_read(regmap, MAX77714_32K_STATUS, &status); + if (err) + return dev_err_probe(dev, err, "Failed to read external oscillator status\n"); + + load_cap_idx = (status >> MAX77714_32K_STATUS_32KLOAD_SHF) + & MAX77714_32K_STATUS_32KLOAD_MSK; + + dev_info(dev, "Using %s oscillator, %d pF load cap\n", + status & MAX77714_32K_STATUS_32KSOURCE ? "internal" : "external", + load_cap[load_cap_idx]); + + return 0; +} + +static int max77714_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct regmap *regmap; + struct regmap_irq_chip_data *irq_data; + int err; + + regmap = devm_regmap_init_i2c(client, &max77714_regmap_config); + if (IS_ERR(regmap)) + return dev_err_probe(dev, PTR_ERR(regmap), + "Failed to initialise regmap\n"); + + err = max77714_setup_xosc(dev, regmap); + if (err) + return err; + + err = devm_regmap_add_irq_chip(dev, regmap, client->irq, + IRQF_ONESHOT | IRQF_SHARED, 0, + &max77714_irq_chip, &irq_data); + if (err) + return dev_err_probe(dev, err, "Failed to add PMIC IRQ chip\n"); + + err = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE, + max77714_cells, ARRAY_SIZE(max77714_cells), + NULL, 0, NULL); + if (err) + return dev_err_probe(dev, err, "Failed to register child devices\n"); + + return 0; +} + +static const struct of_device_id max77714_dt_match[] = { + { .compatible = "maxim,max77714" }, + {}, +}; +MODULE_DEVICE_TABLE(of, max77714_dt_match); + +static struct i2c_driver max77714_driver = { + .driver = { + .name = "max77714", + .of_match_table = max77714_dt_match, + }, + .probe_new = max77714_probe, +}; +module_i2c_driver(max77714_driver); + +MODULE_DESCRIPTION("Maxim MAX77714 MFD core driver"); +MODULE_AUTHOR("Luca Ceresoli <luca@lucaceresoli.net>"); +MODULE_LICENSE("GPL"); |