diff options
Diffstat (limited to 'drivers/iio/pressure/ms5637.c')
| -rw-r--r-- | drivers/iio/pressure/ms5637.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/drivers/iio/pressure/ms5637.c b/drivers/iio/pressure/ms5637.c new file mode 100644 index 000000000000..e3ad9d39b966 --- /dev/null +++ b/drivers/iio/pressure/ms5637.c @@ -0,0 +1,186 @@ +/* + * ms5637.c - Support for Measurement-Specialties ms5637 + * pressure & temperature sensor + * + * Copyright (c) 2015 Measurement-Specialties + * + * Licensed under the GPL-2. + * + * (7-bit I2C slave address 0x76) + * + * Datasheet: + * http://www.meas-spec.com/downloads/MS5637-02BA03.pdf + */ +#include <linux/init.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/stat.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/mutex.h> + +#include "../common/ms_sensors/ms_sensors_i2c.h" + +static const int ms5637_samp_freq[6] = { 960, 480, 240, 120, 60, 30 }; +/* String copy of the above const for readability purpose */ +static const char ms5637_show_samp_freq[] = "960 480 240 120 60 30"; + +static int ms5637_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *channel, int *val, + int *val2, long mask) +{ + int ret; + int temperature; + unsigned int pressure; + struct ms_tp_dev *dev_data = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_PROCESSED: + ret = ms_sensors_read_temp_and_pressure(dev_data, + &temperature, + &pressure); + if (ret) + return ret; + + switch (channel->type) { + case IIO_TEMP: /* in milli °C */ + *val = temperature; + + return IIO_VAL_INT; + case IIO_PRESSURE: /* in kPa */ + *val = pressure / 1000; + *val2 = (pressure % 1000) * 1000; + + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_SAMP_FREQ: + *val = ms5637_samp_freq[dev_data->res_index]; + + return IIO_VAL_INT; + default: + return -EINVAL; + } +} + +static int ms5637_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct ms_tp_dev *dev_data = iio_priv(indio_dev); + int i; + + switch (mask) { + case IIO_CHAN_INFO_SAMP_FREQ: + i = ARRAY_SIZE(ms5637_samp_freq); + while (i-- > 0) + if (val == ms5637_samp_freq[i]) + break; + if (i < 0) + return -EINVAL; + dev_data->res_index = i; + + return 0; + default: + return -EINVAL; + } +} + +static const struct iio_chan_spec ms5637_channels[] = { + { + .type = IIO_TEMP, + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), + }, + { + .type = IIO_PRESSURE, + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), + } +}; + +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(ms5637_show_samp_freq); + +static struct attribute *ms5637_attributes[] = { + &iio_const_attr_sampling_frequency_available.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ms5637_attribute_group = { + .attrs = ms5637_attributes, +}; + +static const struct iio_info ms5637_info = { + .read_raw = ms5637_read_raw, + .write_raw = ms5637_write_raw, + .attrs = &ms5637_attribute_group, + .driver_module = THIS_MODULE, +}; + +static int ms5637_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct ms_tp_dev *dev_data; + struct iio_dev *indio_dev; + int ret; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_WORD_DATA | + I2C_FUNC_SMBUS_WRITE_BYTE | + I2C_FUNC_SMBUS_READ_I2C_BLOCK)) { + dev_err(&client->dev, + "Adapter does not support some i2c transaction\n"); + return -ENODEV; + } + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*dev_data)); + if (!indio_dev) + return -ENOMEM; + + dev_data = iio_priv(indio_dev); + dev_data->client = client; + dev_data->res_index = 5; + mutex_init(&dev_data->lock); + + indio_dev->info = &ms5637_info; + indio_dev->name = id->name; + indio_dev->dev.parent = &client->dev; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = ms5637_channels; + indio_dev->num_channels = ARRAY_SIZE(ms5637_channels); + + i2c_set_clientdata(client, indio_dev); + + ret = ms_sensors_reset(client, 0x1E, 3000); + if (ret) + return ret; + + ret = ms_sensors_tp_read_prom(dev_data); + if (ret) + return ret; + + return devm_iio_device_register(&client->dev, indio_dev); +} + +static const struct i2c_device_id ms5637_id[] = { + {"ms5637", 0}, + {} +}; + +static struct i2c_driver ms5637_driver = { + .probe = ms5637_probe, + .id_table = ms5637_id, + .driver = { + .name = "ms5637" + }, +}; + +module_i2c_driver(ms5637_driver); + +MODULE_DESCRIPTION("Measurement-Specialties ms5637 temperature & pressure driver"); +MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>"); +MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>"); +MODULE_LICENSE("GPL v2"); |