From c984b9cbbd17d3eb602de3802e25d975182474fa Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Sat, 16 Jan 2016 01:00:03 +0900 Subject: iio: pressure: mpl115: support MPL115A1 mpl115 driver currently supports i2c interface (MPL115A2). There is also SPI version (MPL115A1). The difference between them is only physical transport so we can easily support both while sharing most of the code. Split the driver into a core support module and one module each for I2C and SPI support. Signed-off-by: Akinobu Mita Cc: Jonathan Cameron Cc: Hartmut Knaack Cc: Lars-Peter Clausen Cc: Peter Meerwald Cc: linux-iio@vger.kernel.org Signed-off-by: Jonathan Cameron --- drivers/iio/pressure/mpl115_spi.c | 106 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 106 insertions(+) create mode 100644 drivers/iio/pressure/mpl115_spi.c (limited to 'drivers/iio/pressure/mpl115_spi.c') diff --git a/drivers/iio/pressure/mpl115_spi.c b/drivers/iio/pressure/mpl115_spi.c new file mode 100644 index 000000000000..9ebf55f5b3aa --- /dev/null +++ b/drivers/iio/pressure/mpl115_spi.c @@ -0,0 +1,106 @@ +/* + * Freescale MPL115A1 pressure/temperature sensor + * + * Copyright (c) 2016 Akinobu Mita + * + * This file is subject to the terms and conditions of version 2 of + * the GNU General Public License. See the file COPYING in the main + * directory of this archive for more details. + * + * Datasheet: http://www.nxp.com/files/sensors/doc/data_sheet/MPL115A1.pdf + */ + +#include +#include + +#include "mpl115.h" + +#define MPL115_SPI_WRITE(address) ((address) << 1) +#define MPL115_SPI_READ(address) (0x80 | (address) << 1) + +struct mpl115_spi_buf { + u8 tx[4]; + u8 rx[4]; +}; + +static int mpl115_spi_init(struct device *dev) +{ + struct spi_device *spi = to_spi_device(dev); + struct mpl115_spi_buf *buf; + + buf = devm_kzalloc(dev, sizeof(*buf), GFP_KERNEL); + if (!buf) + return -ENOMEM; + + spi_set_drvdata(spi, buf); + + return 0; +} + +static int mpl115_spi_read(struct device *dev, u8 address) +{ + struct spi_device *spi = to_spi_device(dev); + struct mpl115_spi_buf *buf = spi_get_drvdata(spi); + struct spi_transfer xfer = { + .tx_buf = buf->tx, + .rx_buf = buf->rx, + .len = 4, + }; + int ret; + + buf->tx[0] = MPL115_SPI_READ(address); + buf->tx[2] = MPL115_SPI_READ(address + 1); + + ret = spi_sync_transfer(spi, &xfer, 1); + if (ret) + return ret; + + return (buf->rx[1] << 8) | buf->rx[3]; +} + +static int mpl115_spi_write(struct device *dev, u8 address, u8 value) +{ + struct spi_device *spi = to_spi_device(dev); + struct mpl115_spi_buf *buf = spi_get_drvdata(spi); + struct spi_transfer xfer = { + .tx_buf = buf->tx, + .len = 2, + }; + + buf->tx[0] = MPL115_SPI_WRITE(address); + buf->tx[1] = value; + + return spi_sync_transfer(spi, &xfer, 1); +} + +static const struct mpl115_ops mpl115_spi_ops = { + .init = mpl115_spi_init, + .read = mpl115_spi_read, + .write = mpl115_spi_write, +}; + +static int mpl115_spi_probe(struct spi_device *spi) +{ + const struct spi_device_id *id = spi_get_device_id(spi); + + return mpl115_probe(&spi->dev, id->name, &mpl115_spi_ops); +} + +static const struct spi_device_id mpl115_spi_ids[] = { + { "mpl115", 0 }, + {} +}; +MODULE_DEVICE_TABLE(spi, mpl115_spi_ids); + +static struct spi_driver mpl115_spi_driver = { + .driver = { + .name = "mpl115", + }, + .probe = mpl115_spi_probe, + .id_table = mpl115_spi_ids, +}; +module_spi_driver(mpl115_spi_driver); + +MODULE_AUTHOR("Akinobu Mita "); +MODULE_DESCRIPTION("Freescale MPL115A1 pressure/temperature driver"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3