From: Joel Stanley <j...@jms.id.au> The DPS310 is a temperature and pressure sensor. It can be accessed over i2c and SPI.
Signed-off-by: Eddie James <eaja...@linux.ibm.com> --- MAINTAINERS | 6 + drivers/iio/pressure/Kconfig | 10 + drivers/iio/pressure/Makefile | 1 + drivers/iio/pressure/dps310.c | 429 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 446 insertions(+) create mode 100644 drivers/iio/pressure/dps310.c diff --git a/MAINTAINERS b/MAINTAINERS index c61c49d..a91dfa9 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7743,6 +7743,12 @@ W: http://industrypack.sourceforge.net S: Maintained F: drivers/ipack/ +INFINEON DPS310 Driver +M: Eddie James <eaja...@linux.ibm.com> +L: linux-...@vger.kernel.org +F: drivers/iio/pressure/dps310.c +S: Maintained + INFINIBAND SUBSYSTEM M: Doug Ledford <dledf...@redhat.com> M: Jason Gunthorpe <j...@mellanox.com> diff --git a/drivers/iio/pressure/Kconfig b/drivers/iio/pressure/Kconfig index efeb89f..681a1cc 100644 --- a/drivers/iio/pressure/Kconfig +++ b/drivers/iio/pressure/Kconfig @@ -52,6 +52,16 @@ config IIO_CROS_EC_BARO To compile this driver as a module, choose M here: the module will be called cros_ec_baro. +config DPS310 + tristate "Infineon DPS310 pressure and temperature sensor" + depends on I2C + select REGMAP_I2C + help + Support for the Infineon DPS310 digital barometric pressure sensor. + + This driver can also be built as a module. If so, the module will be + called dps310. + config HID_SENSOR_PRESS depends on HID_SENSOR_HUB select IIO_BUFFER diff --git a/drivers/iio/pressure/Makefile b/drivers/iio/pressure/Makefile index c2058d7..d8f5ace 100644 --- a/drivers/iio/pressure/Makefile +++ b/drivers/iio/pressure/Makefile @@ -9,6 +9,7 @@ obj-$(CONFIG_BMP280) += bmp280.o bmp280-objs := bmp280-core.o bmp280-regmap.o obj-$(CONFIG_BMP280_I2C) += bmp280-i2c.o obj-$(CONFIG_BMP280_SPI) += bmp280-spi.o +obj-$(CONFIG_DPS310) += dps310.o obj-$(CONFIG_IIO_CROS_EC_BARO) += cros_ec_baro.o obj-$(CONFIG_HID_SENSOR_PRESS) += hid-sensor-press.o obj-$(CONFIG_HP03) += hp03.o diff --git a/drivers/iio/pressure/dps310.c b/drivers/iio/pressure/dps310.c new file mode 100644 index 0000000..21d5dcb --- /dev/null +++ b/drivers/iio/pressure/dps310.c @@ -0,0 +1,429 @@ +// SPDX-License-Identifier: GPL-2.0+ +// Copyright IBM Corp 2019 +/* + * The DPS310 is a barometric pressure and temperature sensor. + * Currently only reading a single temperature is supported by + * this driver. + * + * https://www.infineon.com/dgdl/?fileId=5546d462576f34750157750826c42242 + * + * Temperature calculation: + * c0 * 0.5 + c1 * T_raw / kT °C + * + * TODO: + * - Pressure sensor readings + * - Optionally support the FIFO + */ + +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/regmap.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> + +#define DPS310_PRS_B0 0x00 +#define DPS310_PRS_B1 0x01 +#define DPS310_PRS_B2 0x02 +#define DPS310_TMP_B0 0x03 +#define DPS310_TMP_B1 0x04 +#define DPS310_TMP_B2 0x05 +#define DPS310_PRS_CFG 0x06 +#define DPS310_TMP_CFG 0x07 +#define DPS310_TMP_RATE_BITS GENMASK(6, 4) +#define DPS310_TMP_PRC_BITS GENMASK(3, 0) +#define DPS310_TMP_EXT BIT(7) +#define DPS310_MEAS_CFG 0x08 +#define DPS310_MEAS_CTRL_BITS GENMASK(2, 0) +#define DPS310_PRS_EN BIT(0) +#define DPS310_TEMP_EN BIT(1) +#define DPS310_BACKGROUND BIT(2) +#define DPS310_PRS_RDY BIT(4) +#define DPS310_TMP_RDY BIT(5) +#define DPS310_SENSOR_RDY BIT(6) +#define DPS310_COEF_RDY BIT(7) +#define DPS310_CFG_REG 0x09 +#define DPS310_INT_HL BIT(7) +#define DPS310_TMP_SHIFT_EN BIT(3) +#define DPS310_PRS_SHIFT_EN BIT(4) +#define DPS310_FIFO_EN BIT(5) +#define DPS310_SPI_EN BIT(6) +#define DPS310_RESET 0x0c +#define DPS310_RESET_MAGIC (BIT(0) | BIT(3)) +#define DPS310_COEF_BASE 0x10 + +#define DPS310_PRS_BASE DPS310_PRS_B0 +#define DPS310_TMP_BASE DPS310_TMP_B0 + +#define DPS310_CALC_RATE(_n) ilog2(_n) +#define DPS310_CALC_PRC(_n) ilog2(_n) + +const int scale_factor[] = { + 524288, + 1572864, + 3670016, + 7864320, + 253952, + 516096, + 1040384, + 2088960, +}; + +struct dps310_data { + struct i2c_client *client; + struct regmap *regmap; + + s32 c0, c1; + s32 temp_raw; +}; + +static const struct iio_chan_spec dps310_channels[] = { + { + .type = IIO_TEMP, + .info_mask_separate = BIT(IIO_CHAN_INFO_OFFSET) | + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | + BIT(IIO_CHAN_INFO_SAMP_FREQ) | + BIT(IIO_CHAN_INFO_RAW), + }, +}; + +/* To be called after checking the TMP_RDY bit in MEAS_CFG */ +static int dps310_get_temp_coef(struct dps310_data *data) +{ + struct regmap *regmap = data->regmap; + u8 coef[3] = {0}; + int r; + u32 c0, c1; + + /* + * Read temperature calibration coefficients c0 and c1 from the + * COEF register. The numbers are 12-bit 2's compliment numbers + */ + r = regmap_bulk_read(regmap, DPS310_COEF_BASE, coef, 3); + if (r < 0) + return r; + + c0 = (coef[0] << 4) | (coef[1] >> 4); + data->c0 = sign_extend32(c0, 11); + + c1 = ((coef[1] & GENMASK(3, 0)) << 8) | coef[2]; + data->c1 = sign_extend32(c1, 11); + + return 0; +} + +static int dps310_get_temp_precision(struct dps310_data *data) +{ + int val, r; + + r = regmap_read(data->regmap, DPS310_TMP_CFG, &val); + if (r < 0) + return r; + + /* + * Scale factor is bottom 4 bits of the register, but 1111 is + * reserved so just grab bottom three + */ + return BIT(val & GENMASK(2, 0)); +} + +static int dps310_set_temp_precision(struct dps310_data *data, int val) +{ + int ret; + u8 shift_en; + + if (val < 0 || val > 128) + return -EINVAL; + + shift_en = val >= 16 ? DPS310_TMP_SHIFT_EN : 0; + ret = regmap_write_bits(data->regmap, DPS310_CFG_REG, + DPS310_TMP_SHIFT_EN, shift_en); + if (ret) + return ret; + + return regmap_update_bits(data->regmap, DPS310_TMP_CFG, + DPS310_TMP_PRC_BITS, DPS310_CALC_PRC(val)); +} + +static int dps310_set_temp_samp_freq(struct dps310_data *data, int freq) +{ + u8 val; + + if (freq < 0 || freq > 128) + return -EINVAL; + + val = DPS310_CALC_RATE(freq) << 4; + + return regmap_update_bits(data->regmap, DPS310_TMP_CFG, + DPS310_TMP_RATE_BITS, val); +} + +static int dps310_get_temp_samp_freq(struct dps310_data *data) +{ + int val, r; + + r = regmap_read(data->regmap, DPS310_TMP_CFG, &val); + if (r < 0) + return r; + + return BIT((val & DPS310_TMP_RATE_BITS) >> 4); +} + +static int dps310_get_temp_k(struct dps310_data *data) +{ + int r = dps310_get_temp_precision(data); + + if (r < 0) + return r; + + return scale_factor[DPS310_CALC_PRC(r)]; +} + +static int dps310_read_temp(struct dps310_data *data) +{ + struct device *dev = &data->client->dev; + struct regmap *regmap = data->regmap; + u8 val[3] = {0}; + int r, ready; + int T_raw; + + r = regmap_read(regmap, DPS310_MEAS_CFG, &ready); + if (r < 0) + return r; + if (!(ready & DPS310_TMP_RDY)) { + dev_dbg(dev, "temperature not ready\n"); + return -EAGAIN; + } + + r = regmap_bulk_read(regmap, DPS310_TMP_BASE, val, 3); + if (r < 0) + return r; + + T_raw = (val[0] << 16) | (val[1] << 8) | val[2]; + data->temp_raw = sign_extend32(T_raw, 23); + + return 0; +} + +static bool dps310_is_writeable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case DPS310_PRS_CFG: + case DPS310_TMP_CFG: + case DPS310_MEAS_CFG: + case DPS310_CFG_REG: + case DPS310_RESET: + return true; + default: + return false; + } +} + +static bool dps310_is_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case DPS310_PRS_B0: + case DPS310_PRS_B1: + case DPS310_PRS_B2: + case DPS310_TMP_B0: + case DPS310_TMP_B1: + case DPS310_TMP_B2: + case DPS310_MEAS_CFG: + return true; + default: + return false; + } +} + +static int dps310_write_raw(struct iio_dev *iio, + struct iio_chan_spec const *chan, int val, + int val2, long mask) +{ + struct dps310_data *data = iio_priv(iio); + + if (chan->type != IIO_TEMP) + return -EINVAL; + + switch (mask) { + case IIO_CHAN_INFO_SAMP_FREQ: + return dps310_set_temp_samp_freq(data, val); + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + return dps310_set_temp_precision(data, val); + default: + return -EINVAL; + } + + return -EINVAL; +} + +static int dps310_read_raw(struct iio_dev *iio, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct dps310_data *data = iio_priv(iio); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_SAMP_FREQ: + *val = dps310_get_temp_samp_freq(data); + return IIO_VAL_INT; + + case IIO_CHAN_INFO_RAW: + ret = dps310_read_temp(data); + if (ret) + return ret; + + *val = data->temp_raw * data->c1; + return IIO_VAL_INT; + + case IIO_CHAN_INFO_OFFSET: + ret = dps310_get_temp_k(data); + if (ret < 0) + return ret; + + *val = (data->c0 >> 1) * ret; + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + ret = dps310_get_temp_k(data); + if (ret < 0) + return ret; + + *val = 1000; /* milliCelsius per Celsius */ + *val2 = ret; + return IIO_VAL_FRACTIONAL; + + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: + *val = dps310_get_temp_precision(data); + return IIO_VAL_INT; + + default: + return -EINVAL; + } + + return -EINVAL; +} + +static const struct regmap_config dps310_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .writeable_reg = dps310_is_writeable_reg, + .volatile_reg = dps310_is_volatile_reg, + .cache_type = REGCACHE_RBTREE, + .max_register = 0x29, +}; + +static const struct iio_info dps310_info = { + .read_raw = dps310_read_raw, + .write_raw = dps310_write_raw, +}; + +static int dps310_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct dps310_data *data; + struct iio_dev *iio; + int r, ready; + + iio = devm_iio_device_alloc(&client->dev, sizeof(*data)); + if (!iio) + return -ENOMEM; + + data = iio_priv(iio); + data->client = client; + + iio->dev.parent = &client->dev; + iio->name = id->name; + iio->channels = dps310_channels; + iio->num_channels = ARRAY_SIZE(dps310_channels); + iio->info = &dps310_info; + iio->modes = INDIO_DIRECT_MODE; + + data->regmap = devm_regmap_init_i2c(client, &dps310_regmap_config); + if (IS_ERR(data->regmap)) + return PTR_ERR(data->regmap); + + /* + * Set up external (MEMS) temperature sensor in single sample, one + * measurement per second mode + */ + r = regmap_write(data->regmap, DPS310_TMP_CFG, + DPS310_TMP_EXT | DPS310_CALC_RATE(1) | + DPS310_CALC_PRC(1)); + if (r < 0) + goto err; + + /* Temp shift is disabled when PRC <= 8 */ + r = regmap_write_bits(data->regmap, DPS310_CFG_REG, + DPS310_TMP_SHIFT_EN, 0); + if (r < 0) + goto err; + + /* Turn on temperature measurement in the background */ + r = regmap_write_bits(data->regmap, DPS310_MEAS_CFG, + DPS310_MEAS_CTRL_BITS, + DPS310_TEMP_EN | DPS310_BACKGROUND); + if (r < 0) + goto err; + + /* + * Calibration coefficients required for reporting temperature. + * They are available 40ms after the device has started + */ + r = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, + ready & DPS310_COEF_RDY, 10000, 40000); + if (r < 0) + goto err; + + r = dps310_get_temp_coef(data); + if (r < 0) + goto err; + + r = devm_iio_device_register(&client->dev, iio); + if (r) + goto err; + + i2c_set_clientdata(client, iio); + + dev_info(&client->dev, "%s: sensor '%s'\n", dev_name(&iio->dev), + client->name); + + return 0; + +err: + regmap_write(data->regmap, DPS310_RESET, DPS310_RESET_MAGIC); + return r; +} + +static int dps310_remove(struct i2c_client *client) +{ + struct dps310_data *data = i2c_get_clientdata(client); + + return regmap_write(data->regmap, DPS310_RESET, DPS310_RESET_MAGIC); +} + +static const struct i2c_device_id dps310_id[] = { + { "dps310", 0 }, + {} +}; +MODULE_DEVICE_TABLE(i2c, dps310_id); + +static const unsigned short normal_i2c[] = { + 0x77, 0x76, I2C_CLIENT_END +}; + +static struct i2c_driver dps310_driver = { + .driver = { + .name = "dps310", + }, + .probe = dps310_probe, + .remove = dps310_remove, + .address_list = normal_i2c, + .id_table = dps310_id, +}; +module_i2c_driver(dps310_driver); + +MODULE_AUTHOR("Joel Stanley <j...@jms.id.au>"); +MODULE_DESCRIPTION("Infineon DPS310 pressure and temperature sensor"); +MODULE_LICENSE("GPL v2"); -- 2.7.4
