drivers/mfd/max77714.c

Source file repositories/reference/linux-study-clean/drivers/mfd/max77714.c

File Facts

System
Linux kernel
Corpus path
drivers/mfd/max77714.c
Extension
.c
Size
4783 bytes
Lines
153
Domain
Driver Families
Bucket
drivers/mfd
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Maxim MAX77714 Core Driver
 *
 * Copyright (C) 2022 Luca Ceresoli
 * Author: Luca Ceresoli <luca.ceresoli@bootlin.com>
 */

#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);

Annotation

Implementation Notes