1 files changed, 137 insertions, 0 deletions
diff --git a/drivers/iio/pressure/ms5611_spi.c b/drivers/iio/pressure/ms5611_spi.c
new file mode 100644
index 0000000000..cc9d1f68c5
--- /dev/null
+++ b/drivers/iio/pressure/ms5611_spi.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MS5611 pressure and temperature sensor driver (SPI bus)
+ *
+ * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/mod_devicetable.h>
+
+#include <asm/unaligned.h>
+
+#include "ms5611.h"
+
+static int ms5611_spi_reset(struct ms5611_state *st)
+{
+	u8 cmd = MS5611_RESET;
+
+	return spi_write_then_read(st->client, &cmd, 1, NULL, 0);
+}
+
+static int ms5611_spi_read_prom_word(struct ms5611_state *st, int index,
+				     u16 *word)
+{
+	int ret;
+
+	ret = spi_w8r16be(st->client, MS5611_READ_PROM_WORD + (index << 1));
+	if (ret < 0)
+		return ret;
+
+	*word = ret;
+
+	return 0;
+}
+
+static int ms5611_spi_read_adc(struct ms5611_state *st, s32 *val)
+{
+	int ret;
+	u8 buf[3] = { MS5611_READ_ADC };
+
+	ret = spi_write_then_read(st->client, buf, 1, buf, 3);
+	if (ret < 0)
+		return ret;
+
+	*val = get_unaligned_be24(&buf[0]);
+
+	return 0;
+}
+
+static int ms5611_spi_read_adc_temp_and_pressure(struct ms5611_state *st,
+						 s32 *temp, s32 *pressure)
+{
+	int ret;
+	const struct ms5611_osr *osr = st->temp_osr;
+
+	/*
+	 * Warning: &osr->cmd MUST be aligned on a word boundary since used as
+	 * 2nd argument (void*) of spi_write_then_read.
+	 */
+	ret = spi_write_then_read(st->client, &osr->cmd, 1, NULL, 0);
+	if (ret < 0)
+		return ret;
+
+	usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));
+	ret = ms5611_spi_read_adc(st, temp);
+	if (ret < 0)
+		return ret;
+
+	osr = st->pressure_osr;
+	ret = spi_write_then_read(st->client, &osr->cmd, 1, NULL, 0);
+	if (ret < 0)
+		return ret;
+
+	usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));
+	return ms5611_spi_read_adc(st, pressure);
+}
+
+static int ms5611_spi_probe(struct spi_device *spi)
+{
+	int ret;
+	struct ms5611_state *st;
+	struct iio_dev *indio_dev;
+
+	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	spi_set_drvdata(spi, indio_dev);
+
+	spi->mode = SPI_MODE_0;
+	spi->max_speed_hz = min(spi->max_speed_hz, 20000000U);
+	spi->bits_per_word = 8;
+	ret = spi_setup(spi);
+	if (ret < 0)
+		return ret;
+
+	st = iio_priv(indio_dev);
+	st->reset = ms5611_spi_reset;
+	st->read_prom_word = ms5611_spi_read_prom_word;
+	st->read_adc_temp_and_pressure = ms5611_spi_read_adc_temp_and_pressure;
+	st->client = spi;
+
+	return ms5611_probe(indio_dev, &spi->dev, spi_get_device_id(spi)->name,
+			    spi_get_device_id(spi)->driver_data);
+}
+
+static const struct of_device_id ms5611_spi_matches[] = {
+	{ .compatible = "meas,ms5611" },
+	{ .compatible = "meas,ms5607" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ms5611_spi_matches);
+
+static const struct spi_device_id ms5611_id[] = {
+	{ "ms5611", MS5611 },
+	{ "ms5607", MS5607 },
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, ms5611_id);
+
+static struct spi_driver ms5611_driver = {
+	.driver = {
+		.name = "ms5611",
+		.of_match_table = ms5611_spi_matches
+	},
+	.id_table = ms5611_id,
+	.probe = ms5611_spi_probe,
+};
+module_spi_driver(ms5611_driver);
+
+MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
+MODULE_DESCRIPTION("MS5611 spi driver");
+MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(IIO_MS5611);