162306a36Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0-only
262306a36Sopenharmony_ci/*
362306a36Sopenharmony_ci * Freescale MPL115A1 pressure/temperature sensor
462306a36Sopenharmony_ci *
562306a36Sopenharmony_ci * Copyright (c) 2016 Akinobu Mita <akinobu.mita@gmail.com>
662306a36Sopenharmony_ci *
762306a36Sopenharmony_ci * Datasheet: http://www.nxp.com/files/sensors/doc/data_sheet/MPL115A1.pdf
862306a36Sopenharmony_ci */
962306a36Sopenharmony_ci
1062306a36Sopenharmony_ci#include <linux/module.h>
1162306a36Sopenharmony_ci#include <linux/spi/spi.h>
1262306a36Sopenharmony_ci
1362306a36Sopenharmony_ci#include "mpl115.h"
1462306a36Sopenharmony_ci
1562306a36Sopenharmony_ci#define MPL115_SPI_WRITE(address)	((address) << 1)
1662306a36Sopenharmony_ci#define MPL115_SPI_READ(address)	(0x80 | (address) << 1)
1762306a36Sopenharmony_ci
1862306a36Sopenharmony_cistruct mpl115_spi_buf {
1962306a36Sopenharmony_ci	u8 tx[4];
2062306a36Sopenharmony_ci	u8 rx[4];
2162306a36Sopenharmony_ci};
2262306a36Sopenharmony_ci
2362306a36Sopenharmony_cistatic int mpl115_spi_init(struct device *dev)
2462306a36Sopenharmony_ci{
2562306a36Sopenharmony_ci	struct spi_device *spi = to_spi_device(dev);
2662306a36Sopenharmony_ci	struct mpl115_spi_buf *buf;
2762306a36Sopenharmony_ci
2862306a36Sopenharmony_ci	buf = devm_kzalloc(dev, sizeof(*buf), GFP_KERNEL);
2962306a36Sopenharmony_ci	if (!buf)
3062306a36Sopenharmony_ci		return -ENOMEM;
3162306a36Sopenharmony_ci
3262306a36Sopenharmony_ci	spi_set_drvdata(spi, buf);
3362306a36Sopenharmony_ci
3462306a36Sopenharmony_ci	return 0;
3562306a36Sopenharmony_ci}
3662306a36Sopenharmony_ci
3762306a36Sopenharmony_cistatic int mpl115_spi_read(struct device *dev, u8 address)
3862306a36Sopenharmony_ci{
3962306a36Sopenharmony_ci	struct spi_device *spi = to_spi_device(dev);
4062306a36Sopenharmony_ci	struct mpl115_spi_buf *buf = spi_get_drvdata(spi);
4162306a36Sopenharmony_ci	struct spi_transfer xfer = {
4262306a36Sopenharmony_ci		.tx_buf = buf->tx,
4362306a36Sopenharmony_ci		.rx_buf = buf->rx,
4462306a36Sopenharmony_ci		.len = 4,
4562306a36Sopenharmony_ci	};
4662306a36Sopenharmony_ci	int ret;
4762306a36Sopenharmony_ci
4862306a36Sopenharmony_ci	buf->tx[0] = MPL115_SPI_READ(address);
4962306a36Sopenharmony_ci	buf->tx[2] = MPL115_SPI_READ(address + 1);
5062306a36Sopenharmony_ci
5162306a36Sopenharmony_ci	ret = spi_sync_transfer(spi, &xfer, 1);
5262306a36Sopenharmony_ci	if (ret)
5362306a36Sopenharmony_ci		return ret;
5462306a36Sopenharmony_ci
5562306a36Sopenharmony_ci	return (buf->rx[1] << 8) | buf->rx[3];
5662306a36Sopenharmony_ci}
5762306a36Sopenharmony_ci
5862306a36Sopenharmony_cistatic int mpl115_spi_write(struct device *dev, u8 address, u8 value)
5962306a36Sopenharmony_ci{
6062306a36Sopenharmony_ci	struct spi_device *spi = to_spi_device(dev);
6162306a36Sopenharmony_ci	struct mpl115_spi_buf *buf = spi_get_drvdata(spi);
6262306a36Sopenharmony_ci	struct spi_transfer xfer = {
6362306a36Sopenharmony_ci		.tx_buf = buf->tx,
6462306a36Sopenharmony_ci		.len = 2,
6562306a36Sopenharmony_ci	};
6662306a36Sopenharmony_ci
6762306a36Sopenharmony_ci	buf->tx[0] = MPL115_SPI_WRITE(address);
6862306a36Sopenharmony_ci	buf->tx[1] = value;
6962306a36Sopenharmony_ci
7062306a36Sopenharmony_ci	return spi_sync_transfer(spi, &xfer, 1);
7162306a36Sopenharmony_ci}
7262306a36Sopenharmony_ci
7362306a36Sopenharmony_cistatic const struct mpl115_ops mpl115_spi_ops = {
7462306a36Sopenharmony_ci	.init = mpl115_spi_init,
7562306a36Sopenharmony_ci	.read = mpl115_spi_read,
7662306a36Sopenharmony_ci	.write = mpl115_spi_write,
7762306a36Sopenharmony_ci};
7862306a36Sopenharmony_ci
7962306a36Sopenharmony_cistatic int mpl115_spi_probe(struct spi_device *spi)
8062306a36Sopenharmony_ci{
8162306a36Sopenharmony_ci	const struct spi_device_id *id = spi_get_device_id(spi);
8262306a36Sopenharmony_ci
8362306a36Sopenharmony_ci	return mpl115_probe(&spi->dev, id->name, &mpl115_spi_ops);
8462306a36Sopenharmony_ci}
8562306a36Sopenharmony_ci
8662306a36Sopenharmony_cistatic const struct spi_device_id mpl115_spi_ids[] = {
8762306a36Sopenharmony_ci	{ "mpl115", 0 },
8862306a36Sopenharmony_ci	{}
8962306a36Sopenharmony_ci};
9062306a36Sopenharmony_ciMODULE_DEVICE_TABLE(spi, mpl115_spi_ids);
9162306a36Sopenharmony_ci
9262306a36Sopenharmony_cistatic struct spi_driver mpl115_spi_driver = {
9362306a36Sopenharmony_ci	.driver = {
9462306a36Sopenharmony_ci		.name   = "mpl115",
9562306a36Sopenharmony_ci		.pm = pm_ptr(&mpl115_dev_pm_ops),
9662306a36Sopenharmony_ci	},
9762306a36Sopenharmony_ci	.probe = mpl115_spi_probe,
9862306a36Sopenharmony_ci	.id_table = mpl115_spi_ids,
9962306a36Sopenharmony_ci};
10062306a36Sopenharmony_cimodule_spi_driver(mpl115_spi_driver);
10162306a36Sopenharmony_ci
10262306a36Sopenharmony_ciMODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");
10362306a36Sopenharmony_ciMODULE_DESCRIPTION("Freescale MPL115A1 pressure/temperature driver");
10462306a36Sopenharmony_ciMODULE_LICENSE("GPL");
10562306a36Sopenharmony_ciMODULE_IMPORT_NS(IIO_MPL115);
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