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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Maxim MAX77714 Core Driver4 *5 * Copyright (C) 2022 Luca Ceresoli6 * Author: Luca Ceresoli <luca.ceresoli@bootlin.com>7 */8 9#include <linux/i2c.h>10#include <linux/interrupt.h>11#include <linux/mfd/core.h>12#include <linux/mfd/max77714.h>13#include <linux/module.h>14#include <linux/of.h>15#include <linux/regmap.h>16 17static const struct mfd_cell max77714_cells[] = {18 { .name = "max77714-watchdog" },19 { .name = "max77714-rtc" },20};21 22static const struct regmap_range max77714_readable_ranges[] = {23 regmap_reg_range(MAX77714_INT_TOP, MAX77714_INT_TOP),24 regmap_reg_range(MAX77714_INT_TOPM, MAX77714_INT_TOPM),25 regmap_reg_range(MAX77714_32K_STATUS, MAX77714_32K_CONFIG),26 regmap_reg_range(MAX77714_CNFG_GLBL2, MAX77714_CNFG2_ONOFF),27};28 29static const struct regmap_range max77714_writable_ranges[] = {30 regmap_reg_range(MAX77714_INT_TOPM, MAX77714_INT_TOPM),31 regmap_reg_range(MAX77714_32K_CONFIG, MAX77714_32K_CONFIG),32 regmap_reg_range(MAX77714_CNFG_GLBL2, MAX77714_CNFG2_ONOFF),33};34 35static const struct regmap_access_table max77714_readable_table = {36 .yes_ranges = max77714_readable_ranges,37 .n_yes_ranges = ARRAY_SIZE(max77714_readable_ranges),38};39 40static const struct regmap_access_table max77714_writable_table = {41 .yes_ranges = max77714_writable_ranges,42 .n_yes_ranges = ARRAY_SIZE(max77714_writable_ranges),43};44 45static const struct regmap_config max77714_regmap_config = {46 .reg_bits = 8,47 .val_bits = 8,48 .max_register = MAX77714_CNFG2_ONOFF,49 .rd_table = &max77714_readable_table,50 .wr_table = &max77714_writable_table,51};52 53static const struct regmap_irq max77714_top_irqs[] = {54 REGMAP_IRQ_REG(MAX77714_IRQ_TOP_ONOFF, 0, MAX77714_INT_TOP_ONOFF),55 REGMAP_IRQ_REG(MAX77714_IRQ_TOP_RTC, 0, MAX77714_INT_TOP_RTC),56 REGMAP_IRQ_REG(MAX77714_IRQ_TOP_GPIO, 0, MAX77714_INT_TOP_GPIO),57 REGMAP_IRQ_REG(MAX77714_IRQ_TOP_LDO, 0, MAX77714_INT_TOP_LDO),58 REGMAP_IRQ_REG(MAX77714_IRQ_TOP_SD, 0, MAX77714_INT_TOP_SD),59 REGMAP_IRQ_REG(MAX77714_IRQ_TOP_GLBL, 0, MAX77714_INT_TOP_GLBL),60};61 62static const struct regmap_irq_chip max77714_irq_chip = {63 .name = "max77714-pmic",64 .status_base = MAX77714_INT_TOP,65 .mask_base = MAX77714_INT_TOPM,66 .num_regs = 1,67 .irqs = max77714_top_irqs,68 .num_irqs = ARRAY_SIZE(max77714_top_irqs),69};70 71/*72 * MAX77714 initially uses the internal, low precision oscillator. Enable73 * the external oscillator by setting the XOSC_RETRY bit. If the external74 * oscillator is not OK (probably not installed) this has no effect.75 */76static int max77714_setup_xosc(struct device *dev, struct regmap *regmap)77{78 /* Internal Crystal Load Capacitance, indexed by value of 32KLOAD bits */79 static const unsigned int load_cap[4] = {0, 10, 12, 22}; /* pF */80 unsigned int load_cap_idx;81 unsigned int status;82 int err;83 84 err = regmap_update_bits(regmap, MAX77714_32K_CONFIG,85 MAX77714_32K_CONFIG_XOSC_RETRY,86 MAX77714_32K_CONFIG_XOSC_RETRY);87 if (err)88 return dev_err_probe(dev, err, "Failed to configure the external oscillator\n");89 90 err = regmap_read(regmap, MAX77714_32K_STATUS, &status);91 if (err)92 return dev_err_probe(dev, err, "Failed to read external oscillator status\n");93 94 load_cap_idx = (status >> MAX77714_32K_STATUS_32KLOAD_SHF)95 & MAX77714_32K_STATUS_32KLOAD_MSK;96 97 dev_info(dev, "Using %s oscillator, %d pF load cap\n",98 status & MAX77714_32K_STATUS_32KSOURCE ? "internal" : "external",99 load_cap[load_cap_idx]);100 101 return 0;102}103 104static int max77714_probe(struct i2c_client *client)105{106 struct device *dev = &client->dev;107 struct regmap *regmap;108 struct regmap_irq_chip_data *irq_data;109 int err;110 111 regmap = devm_regmap_init_i2c(client, &max77714_regmap_config);112 if (IS_ERR(regmap))113 return dev_err_probe(dev, PTR_ERR(regmap),114 "Failed to initialise regmap\n");115 116 err = max77714_setup_xosc(dev, regmap);117 if (err)118 return err;119 120 err = devm_regmap_add_irq_chip(dev, regmap, client->irq,121 IRQF_ONESHOT | IRQF_SHARED, 0,122 &max77714_irq_chip, &irq_data);123 if (err)124 return dev_err_probe(dev, err, "Failed to add PMIC IRQ chip\n");125 126 err = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,127 max77714_cells, ARRAY_SIZE(max77714_cells),128 NULL, 0, NULL);129 if (err)130 return dev_err_probe(dev, err, "Failed to register child devices\n");131 132 return 0;133}134 135static const struct of_device_id max77714_dt_match[] = {136 { .compatible = "maxim,max77714" },137 {},138};139MODULE_DEVICE_TABLE(of, max77714_dt_match);140 141static struct i2c_driver max77714_driver = {142 .driver = {143 .name = "max77714",144 .of_match_table = max77714_dt_match,145 },146 .probe = max77714_probe,147};148module_i2c_driver(max77714_driver);149 150MODULE_DESCRIPTION("Maxim MAX77714 MFD core driver");151MODULE_AUTHOR("Luca Ceresoli <luca.ceresoli@bootlin.com>");152MODULE_LICENSE("GPL");153