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authorTomasz Duszynski <tduszyns@gmail.com>2015-03-14 21:29:31 +0100
committerJonathan Cameron <jic23@kernel.org>2015-03-15 11:47:46 +0000
commitc0644160a8b5e56b3c3896d77ac3d50d41fa9336 (patch)
tree9cd8486122d69d05455b20b7e831758e55917514 /drivers/iio/pressure/ms5611_i2c.c
parent8b0544263761adbc7308f6910cdcc0d601782cb1 (diff)
iio: pressure: add support for MS5611 pressure and temperature sensor
Add support for Measurement Specialities MS5611 pressure and temperature sensor. Signed-off-by: Tomasz Duszynski <tduszyns@gmail.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Diffstat (limited to 'drivers/iio/pressure/ms5611_i2c.c')
-rw-r--r--drivers/iio/pressure/ms5611_i2c.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/drivers/iio/pressure/ms5611_i2c.c b/drivers/iio/pressure/ms5611_i2c.c
new file mode 100644
index 000000000000..748fd9acaad8
--- /dev/null
+++ b/drivers/iio/pressure/ms5611_i2c.c
@@ -0,0 +1,128 @@
+/*
+ * MS5611 pressure and temperature sensor driver (I2C 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.
+ *
+ * 7-bit I2C slave addresses:
+ *
+ * 0x77 (CSB pin low)
+ * 0x76 (CSB pin high)
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+
+#include "ms5611.h"
+
+static int ms5611_i2c_reset(struct device *dev)
+{
+ struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
+
+ return i2c_smbus_write_byte(st->client, MS5611_RESET);
+}
+
+static int ms5611_i2c_read_prom_word(struct device *dev, int index, u16 *word)
+{
+ int ret;
+ struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
+
+ ret = i2c_smbus_read_word_swapped(st->client,
+ MS5611_READ_PROM_WORD + (index << 1));
+ if (ret < 0)
+ return ret;
+
+ *word = ret;
+
+ return 0;
+}
+
+static int ms5611_i2c_read_adc(struct ms5611_state *st, s32 *val)
+{
+ int ret;
+ u8 buf[3];
+
+ ret = i2c_smbus_read_i2c_block_data(st->client, MS5611_READ_ADC,
+ 3, buf);
+ if (ret < 0)
+ return ret;
+
+ *val = (buf[0] << 16) | (buf[1] << 8) | buf[2];
+
+ return 0;
+}
+
+static int ms5611_i2c_read_adc_temp_and_pressure(struct device *dev,
+ s32 *temp, s32 *pressure)
+{
+ int ret;
+ struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
+
+ ret = i2c_smbus_write_byte(st->client, MS5611_START_TEMP_CONV);
+ if (ret < 0)
+ return ret;
+
+ usleep_range(MS5611_CONV_TIME_MIN, MS5611_CONV_TIME_MAX);
+
+ ret = ms5611_i2c_read_adc(st, temp);
+ if (ret < 0)
+ return ret;
+
+ ret = i2c_smbus_write_byte(st->client, MS5611_START_PRESSURE_CONV);
+ if (ret < 0)
+ return ret;
+
+ usleep_range(MS5611_CONV_TIME_MIN, MS5611_CONV_TIME_MAX);
+
+ return ms5611_i2c_read_adc(st, pressure);
+}
+
+static int ms5611_i2c_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct ms5611_state *st;
+ struct iio_dev *indio_dev;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_WRITE_BYTE |
+ I2C_FUNC_SMBUS_READ_WORD_DATA |
+ I2C_FUNC_SMBUS_READ_I2C_BLOCK))
+ return -ENODEV;
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+ st->reset = ms5611_i2c_reset;
+ st->read_prom_word = ms5611_i2c_read_prom_word;
+ st->read_adc_temp_and_pressure = ms5611_i2c_read_adc_temp_and_pressure;
+ st->client = client;
+
+ return ms5611_probe(indio_dev, &client->dev);
+}
+
+static const struct i2c_device_id ms5611_id[] = {
+ { "ms5611", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ms5611_id);
+
+static struct i2c_driver ms5611_driver = {
+ .driver = {
+ .name = "ms5611",
+ .owner = THIS_MODULE,
+ },
+ .id_table = ms5611_id,
+ .probe = ms5611_i2c_probe,
+};
+module_i2c_driver(ms5611_driver);
+
+MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
+MODULE_DESCRIPTION("MS5611 i2c driver");
+MODULE_LICENSE("GPL v2");