drivers/mfd/lp87565.c

Source file repositories/reference/linux-study-clean/drivers/mfd/lp87565.c

File Facts

System
Linux kernel
Corpus path
drivers/mfd/lp87565.c
Extension
.c
Size
3208 bytes
Lines
128
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
/*
 * Copyright (C) 2017 Texas Instruments Incorporated - https://www.ti.com/
 *
 * Author: Keerthy <j-keerthy@ti.com>
 */

#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/mfd/core.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/regmap.h>

#include <linux/mfd/lp87565.h>

static const struct regmap_config lp87565_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = LP87565_REG_MAX,
};

static const struct mfd_cell lp87565_cells[] = {
	{ .name = "lp87565-q1-regulator", },
	{ .name = "lp87565-q1-gpio", },
};

static const struct of_device_id of_lp87565_match_table[] = {
	{ .compatible = "ti,lp87565", },
	{
		.compatible = "ti,lp87524-q1",
		.data = (void *)LP87565_DEVICE_TYPE_LP87524_Q1,
	},
	{
		.compatible = "ti,lp87565-q1",
		.data = (void *)LP87565_DEVICE_TYPE_LP87565_Q1,
	},
	{
		.compatible = "ti,lp87561-q1",
		.data = (void *)LP87565_DEVICE_TYPE_LP87561_Q1,
	},
	{}
};
MODULE_DEVICE_TABLE(of, of_lp87565_match_table);

static int lp87565_probe(struct i2c_client *client)
{
	struct lp87565 *lp87565;
	int ret;
	unsigned int otpid;

	lp87565 = devm_kzalloc(&client->dev, sizeof(*lp87565), GFP_KERNEL);
	if (!lp87565)
		return -ENOMEM;

	lp87565->dev = &client->dev;

	lp87565->regmap = devm_regmap_init_i2c(client, &lp87565_regmap_config);
	if (IS_ERR(lp87565->regmap)) {
		ret = PTR_ERR(lp87565->regmap);
		dev_err(lp87565->dev,
			"Failed to initialize register map: %d\n", ret);
		return ret;
	}

	lp87565->reset_gpio = devm_gpiod_get_optional(lp87565->dev, "reset",
						      GPIOD_OUT_LOW);
	if (IS_ERR(lp87565->reset_gpio)) {
		ret = PTR_ERR(lp87565->reset_gpio);
		if (ret == -EPROBE_DEFER)
			return ret;
	}

	if (lp87565->reset_gpio) {
		gpiod_set_value_cansleep(lp87565->reset_gpio, 1);
		/* The minimum assertion time is undocumented, just guess */
		usleep_range(2000, 4000);

		gpiod_set_value_cansleep(lp87565->reset_gpio, 0);
		/* Min 1.2 ms before first I2C transaction */
		usleep_range(1500, 3000);
	}

	ret = regmap_read(lp87565->regmap, LP87565_REG_OTP_REV, &otpid);
	if (ret) {
		dev_err(lp87565->dev, "Failed to read OTP ID\n");
		return ret;
	}

Annotation

Implementation Notes