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path: root/drivers/iio/pressure/ms5611_spi.c
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Diffstat (limited to 'drivers/iio/pressure/ms5611_spi.c')
-rw-r--r--drivers/iio/pressure/ms5611_spi.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/drivers/iio/pressure/ms5611_spi.c b/drivers/iio/pressure/ms5611_spi.c
new file mode 100644
index 000000000000..976726fd4e6c
--- /dev/null
+++ b/drivers/iio/pressure/ms5611_spi.c
@@ -0,0 +1,127 @@
+/*
+ * MS5611 pressure and temperature sensor driver (SPI bus)
+ *
+ * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+
+#include "ms5611.h"
+
+static int ms5611_spi_reset(struct device *dev)
+{
+ u8 cmd = MS5611_RESET;
+ struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
+
+ return spi_write_then_read(st->client, &cmd, 1, NULL, 0);
+}
+
+static int ms5611_spi_read_prom_word(struct device *dev, int index, u16 *word)
+{
+ int ret;
+ struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
+
+ 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 device *dev, s32 *val)
+{
+ int ret;
+ u8 buf[3] = { MS5611_READ_ADC };
+ struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
+
+ ret = spi_write_then_read(st->client, buf, 1, buf, 3);
+ if (ret < 0)
+ return ret;
+
+ *val = (buf[0] << 16) | (buf[1] << 8) | buf[2];
+
+ return 0;
+}
+
+static int ms5611_spi_read_adc_temp_and_pressure(struct device *dev,
+ s32 *temp, s32 *pressure)
+{
+ u8 cmd;
+ int ret;
+ struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
+
+ cmd = MS5611_START_TEMP_CONV;
+ ret = spi_write_then_read(st->client, &cmd, 1, NULL, 0);
+ if (ret < 0)
+ return ret;
+
+ usleep_range(MS5611_CONV_TIME_MIN, MS5611_CONV_TIME_MAX);
+
+ ret = ms5611_spi_read_adc(dev, temp);
+ if (ret < 0)
+ return ret;
+
+ cmd = MS5611_START_PRESSURE_CONV;
+ ret = spi_write_then_read(st->client, &cmd, 1, NULL, 0);
+ if (ret < 0)
+ return ret;
+
+ usleep_range(MS5611_CONV_TIME_MIN, MS5611_CONV_TIME_MAX);
+
+ return ms5611_spi_read_adc(dev, 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->mode = SPI_MODE_0;
+ spi->max_speed_hz = 20000000;
+ 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);
+}
+
+static const struct spi_device_id ms5611_id[] = {
+ { "ms5611", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, ms5611_id);
+
+static struct spi_driver ms5611_driver = {
+ .driver = {
+ .name = "ms5611",
+ .owner = THIS_MODULE,
+ },
+ .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");