[PATCH v3] iio: pressure: add support for MS5611 pressure and temperature sensor
From: Tomasz Duszynski
Date: Sat Mar 14 2015 - 16:34:39 EST
Add support for Measurement Specialities MS5611 pressure
and temperature sensor.
Signed-off-by: Tomasz Duszynski <tduszyns@xxxxxxxxx>
---
Changes in v3:
- Fix coding style
- Use spi_write_then_read instead of spi_write to ensure that
data send to device is in it's own cacheline
Changes in v2:
- Fix coding style
- Document i2c slave addresses
- Simplify device registration/removal using devm_iio_device_register()
- Return temperature in mC and pressure in kPa
drivers/iio/pressure/Kconfig | 27 +++++
drivers/iio/pressure/Makefile | 3 +
drivers/iio/pressure/ms5611.h | 44 ++++++++
drivers/iio/pressure/ms5611_core.c | 215 +++++++++++++++++++++++++++++++++++++
drivers/iio/pressure/ms5611_i2c.c | 128 ++++++++++++++++++++++
drivers/iio/pressure/ms5611_spi.c | 127 ++++++++++++++++++++++
6 files changed, 544 insertions(+)
create mode 100644 drivers/iio/pressure/ms5611.h
create mode 100644 drivers/iio/pressure/ms5611_core.c
create mode 100644 drivers/iio/pressure/ms5611_i2c.c
create mode 100644 drivers/iio/pressure/ms5611_spi.c
diff --git a/drivers/iio/pressure/Kconfig b/drivers/iio/pressure/Kconfig
index a3be537..fa62950 100644
--- a/drivers/iio/pressure/Kconfig
+++ b/drivers/iio/pressure/Kconfig
@@ -52,6 +52,33 @@ config MPL3115
To compile this driver as a module, choose M here: the module
will be called mpl3115.
+config MS5611
+ tristate "Measurement Specialities MS5611 pressure sensor driver"
+ help
+ Say Y here to build support for the Measurement Specialities
+ MS5611 pressure and temperature sensor.
+
+ To compile this driver as a module, choose M here: the module will
+ be called ms5611_core.
+
+config MS5611_I2C
+ tristate "support I2C bus connection"
+ depends on I2C && MS5611
+ help
+ Say Y here to build I2C bus support for MS5611.
+
+ To compile this driver as a module, choose M here: the module will
+ be called ms5611_i2c.
+
+config MS5611_SPI
+ tristate "support SPI bus connection"
+ depends on SPI_MASTER && MS5611
+ help
+ Say Y here to build SPI bus support for MS5611.
+
+ To compile this driver as a module, choose M here: the module will
+ be called ms5611_spi.
+
config IIO_ST_PRESS
tristate "STMicroelectronics pressure sensor Driver"
depends on (I2C || SPI_MASTER) && SYSFS
diff --git a/drivers/iio/pressure/Makefile b/drivers/iio/pressure/Makefile
index 88011f2..a4f98f8 100644
--- a/drivers/iio/pressure/Makefile
+++ b/drivers/iio/pressure/Makefile
@@ -7,6 +7,9 @@ obj-$(CONFIG_BMP280) += bmp280.o
obj-$(CONFIG_HID_SENSOR_PRESS) += hid-sensor-press.o
obj-$(CONFIG_MPL115) += mpl115.o
obj-$(CONFIG_MPL3115) += mpl3115.o
+obj-$(CONFIG_MS5611) += ms5611_core.o
+obj-$(CONFIG_MS5611_I2C) += ms5611_i2c.o
+obj-$(CONFIG_MS5611_SPI) += ms5611_spi.o
obj-$(CONFIG_IIO_ST_PRESS) += st_pressure.o
st_pressure-y := st_pressure_core.o
st_pressure-$(CONFIG_IIO_BUFFER) += st_pressure_buffer.o
diff --git a/drivers/iio/pressure/ms5611.h b/drivers/iio/pressure/ms5611.h
new file mode 100644
index 0000000..099c6cd
--- /dev/null
+++ b/drivers/iio/pressure/ms5611.h
@@ -0,0 +1,44 @@
+/*
+ * MS5611 pressure and temperature sensor driver
+ *
+ * Copyright (c) Tomasz Duszynski <tduszyns@xxxxxxxxx>
+ *
+ * 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.
+ *
+ */
+
+#ifndef _MS5611_H
+#define _MS5611_H
+
+#include <linux/device.h>
+#include <linux/iio/iio.h>
+#include <linux/mutex.h>
+
+#define MS5611_RESET 0x1e
+#define MS5611_READ_ADC 0x00
+#define MS5611_READ_PROM_WORD 0xA0
+#define MS5611_START_TEMP_CONV 0x58
+#define MS5611_START_PRESSURE_CONV 0x48
+
+#define MS5611_CONV_TIME_MIN 9040
+#define MS5611_CONV_TIME_MAX 10000
+
+#define MS5611_PROM_WORDS_NB 8
+
+struct ms5611_state {
+ void *client;
+ struct mutex lock;
+
+ int (*reset)(struct device *dev);
+ int (*read_prom_word)(struct device *dev, int index, u16 *word);
+ int (*read_adc_temp_and_pressure)(struct device *dev,
+ s32 *temp, s32 *pressure);
+
+ u16 prom[MS5611_PROM_WORDS_NB];
+};
+
+int ms5611_probe(struct iio_dev *indio_dev, struct device *dev);
+
+#endif /* _MS5611_H */
diff --git a/drivers/iio/pressure/ms5611_core.c b/drivers/iio/pressure/ms5611_core.c
new file mode 100644
index 0000000..e42c853
--- /dev/null
+++ b/drivers/iio/pressure/ms5611_core.c
@@ -0,0 +1,215 @@
+/*
+ * MS5611 pressure and temperature sensor driver
+ *
+ * Copyright (c) Tomasz Duszynski <tduszyns@xxxxxxxxx>
+ *
+ * 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.
+ *
+ * Data sheet:
+ * http://www.meas-spec.com/downloads/MS5611-01BA03.pdf
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/iio/iio.h>
+#include <linux/delay.h>
+
+#include "ms5611.h"
+
+static bool ms5611_prom_is_valid(u16 *prom, size_t len)
+{
+ int i, j;
+ uint16_t crc = 0, crc_orig = prom[7] & 0x000F;
+
+ prom[7] &= 0xFF00;
+
+ for (i = 0; i < len * 2; i++) {
+ if (i % 2 == 1)
+ crc ^= prom[i >> 1] & 0x00FF;
+ else
+ crc ^= prom[i >> 1] >> 8;
+
+ for (j = 0; j < 8; j++) {
+ if (crc & 0x8000)
+ crc = (crc << 1) ^ 0x3000;
+ else
+ crc <<= 1;
+ }
+ }
+
+ crc = (crc >> 12) & 0x000F;
+
+ return crc_orig != 0x0000 && crc == crc_orig;
+}
+
+static int ms5611_read_prom(struct iio_dev *indio_dev)
+{
+ int ret, i;
+ struct ms5611_state *st = iio_priv(indio_dev);
+
+ for (i = 0; i < MS5611_PROM_WORDS_NB; i++) {
+ ret = st->read_prom_word(&indio_dev->dev, i, &st->prom[i]);
+ if (ret < 0) {
+ dev_err(&indio_dev->dev,
+ "failed to read prom at %d\n", i);
+ return ret;
+ }
+ }
+
+ if (!ms5611_prom_is_valid(st->prom, MS5611_PROM_WORDS_NB)) {
+ dev_err(&indio_dev->dev, "PROM integrity check failed\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int ms5611_read_temp_and_pressure(struct iio_dev *indio_dev,
+ s32 *temp, s32 *pressure)
+{
+ int ret;
+ s32 t, p;
+ s64 off, sens, dt;
+ struct ms5611_state *st = iio_priv(indio_dev);
+
+ ret = st->read_adc_temp_and_pressure(&indio_dev->dev, &t, &p);
+ if (ret < 0) {
+ dev_err(&indio_dev->dev,
+ "failed to read temperature and pressure\n");
+ return ret;
+ }
+
+ dt = t - (st->prom[5] << 8);
+ off = ((s64)st->prom[2] << 16) + ((st->prom[4] * dt) >> 7);
+ sens = ((s64)st->prom[1] << 15) + ((st->prom[3] * dt) >> 8);
+
+ t = 2000 + ((st->prom[6] * dt) >> 23);
+ if (t < 2000) {
+ s64 off2, sens2, t2;
+
+ t2 = (dt * dt) >> 31;
+ off2 = (5 * (t - 2000) * (t - 2000)) >> 1;
+ sens2 = off2 >> 1;
+
+ if (t < -1500) {
+ s64 tmp = (t + 1500) * (t + 1500);
+
+ off2 += 7 * tmp;
+ sens2 += (11 * tmp) >> 1;
+ }
+
+ t -= t2;
+ off -= off2;
+ sens -= sens2;
+ }
+
+ *temp = t;
+ *pressure = (((p * sens) >> 21) - off) >> 15;
+
+ return 0;
+}
+
+static int ms5611_reset(struct iio_dev *indio_dev)
+{
+ int ret;
+ struct ms5611_state *st = iio_priv(indio_dev);
+
+ ret = st->reset(&indio_dev->dev);
+ if (ret < 0) {
+ dev_err(&indio_dev->dev, "failed to reset device\n");
+ return ret;
+ }
+
+ usleep_range(3000, 4000);
+
+ return 0;
+}
+
+static int ms5611_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ int ret;
+ s32 temp, pressure;
+ struct ms5611_state *st = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_PROCESSED:
+ mutex_lock(&st->lock);
+ ret = ms5611_read_temp_and_pressure(indio_dev,
+ &temp, &pressure);
+ mutex_unlock(&st->lock);
+ if (ret < 0)
+ return ret;
+
+ switch (chan->type) {
+ case IIO_TEMP:
+ *val = temp * 10;
+ return IIO_VAL_INT;
+ case IIO_PRESSURE:
+ *val = pressure / 1000;
+ *val2 = (pressure % 1000) * 1000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static const struct iio_chan_spec ms5611_channels[] = {
+ {
+ .type = IIO_PRESSURE,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+ BIT(IIO_CHAN_INFO_SCALE)
+ },
+ {
+ .type = IIO_TEMP,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+ BIT(IIO_CHAN_INFO_SCALE)
+ }
+};
+
+static const struct iio_info ms5611_info = {
+ .read_raw = &ms5611_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static int ms5611_init(struct iio_dev *indio_dev)
+{
+ int ret;
+
+ ret = ms5611_reset(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ return ms5611_read_prom(indio_dev);
+}
+
+int ms5611_probe(struct iio_dev *indio_dev, struct device *dev)
+{
+ int ret;
+ struct ms5611_state *st = iio_priv(indio_dev);
+
+ mutex_init(&st->lock);
+ indio_dev->dev.parent = dev;
+ indio_dev->name = dev->driver->name;
+ indio_dev->info = &ms5611_info;
+ indio_dev->channels = ms5611_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ms5611_channels);
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = ms5611_init(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ return devm_iio_device_register(dev, indio_dev);
+}
+EXPORT_SYMBOL(ms5611_probe);
+
+MODULE_AUTHOR("Tomasz Duszynski <tduszyns@xxxxxxxxx>");
+MODULE_DESCRIPTION("MS5611 core driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/pressure/ms5611_i2c.c b/drivers/iio/pressure/ms5611_i2c.c
new file mode 100644
index 0000000..748fd9a
--- /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@xxxxxxxxx>
+ *
+ * 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@xxxxxxxxx>");
+MODULE_DESCRIPTION("MS5611 i2c driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/pressure/ms5611_spi.c b/drivers/iio/pressure/ms5611_spi.c
new file mode 100644
index 0000000..976726f
--- /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@xxxxxxxxx>
+ *
+ * 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@xxxxxxxxx>");
+MODULE_DESCRIPTION("MS5611 spi driver");
+MODULE_LICENSE("GPL v2");
--
2.3.2
--
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