1 files changed, 106 insertions, 0 deletions
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 <akinobu.mita@gmail.com>
+ *
+ * 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 <linux/module.h>
+#include <linux/spi/spi.h>
+
+#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 <akinobu.mita@gmail.com>");
+MODULE_DESCRIPTION("Freescale MPL115A1 pressure/temperature driver");
+MODULE_LICENSE("GPL");