drivers/iio/gyro/mpu3050-i2c.c

Source file repositories/reference/linux-study-clean/drivers/iio/gyro/mpu3050-i2c.c

File Facts

System
Linux kernel
Corpus path
drivers/iio/gyro/mpu3050-i2c.c
Extension
.c
Size
3178 bytes
Lines
123
Domain
Driver Families
Bucket
drivers/iio
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
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/i2c-mux.h>
#include <linux/iio/iio.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/pm_runtime.h>

#include "mpu3050.h"

static const struct regmap_config mpu3050_i2c_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
};

static int mpu3050_i2c_bypass_select(struct i2c_mux_core *mux, u32 chan_id)
{
	struct mpu3050 *mpu3050 = i2c_mux_priv(mux);

	/* Just power up the device, that is all that is needed */
	return pm_runtime_resume_and_get(mpu3050->dev);
}

static int mpu3050_i2c_bypass_deselect(struct i2c_mux_core *mux, u32 chan_id)
{
	struct mpu3050 *mpu3050 = i2c_mux_priv(mux);

	pm_runtime_put_autosuspend(mpu3050->dev);
	return 0;
}

static int mpu3050_i2c_probe(struct i2c_client *client)
{
	const struct i2c_device_id *id = i2c_client_get_device_id(client);
	struct regmap *regmap;
	const char *name;
	struct mpu3050 *mpu3050;
	int ret;

	if (!i2c_check_functionality(client->adapter,
				     I2C_FUNC_SMBUS_I2C_BLOCK))
		return -EOPNOTSUPP;

	if (id)
		name = id->name;
	else
		return -ENODEV;

	regmap = devm_regmap_init_i2c(client, &mpu3050_i2c_regmap_config);
	if (IS_ERR(regmap)) {
		dev_err(&client->dev, "Failed to register i2c regmap: %pe\n",
			regmap);
		return PTR_ERR(regmap);
	}

	ret = mpu3050_common_probe(&client->dev, regmap, client->irq, name);
	if (ret)
		return ret;

	/* The main driver is up, now register the I2C mux */
	mpu3050 = iio_priv(dev_get_drvdata(&client->dev));
	mpu3050->i2cmux = i2c_mux_alloc(client->adapter, &client->dev,
					1, 0, I2C_MUX_LOCKED | I2C_MUX_GATE,
					mpu3050_i2c_bypass_select,
					mpu3050_i2c_bypass_deselect);
	/* Just fail the mux, there is no point in killing the driver */
	if (!mpu3050->i2cmux)
		dev_err(&client->dev, "failed to allocate I2C mux\n");
	else {
		mpu3050->i2cmux->priv = mpu3050;
		/* Ignore failure, not critical */
		i2c_mux_add_adapter(mpu3050->i2cmux, 0, 0);
	}

	return 0;
}

static void mpu3050_i2c_remove(struct i2c_client *client)
{
	struct iio_dev *indio_dev = dev_get_drvdata(&client->dev);
	struct mpu3050 *mpu3050 = iio_priv(indio_dev);

	if (mpu3050->i2cmux)
		i2c_mux_del_adapters(mpu3050->i2cmux);

	mpu3050_common_remove(&client->dev);
}

/*

Annotation

Implementation Notes