2019-05-21 02:13:32 +00:00
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// SPDX-License-Identifier: GPL-2.0+
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// Copyright IBM Corp 2019
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/*
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* The DPS310 is a barometric pressure and temperature sensor.
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* Currently only reading a single temperature is supported by
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* this driver.
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*
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* https://www.infineon.com/dgdl/?fileId=5546d462576f34750157750826c42242
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*
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* Temperature calculation:
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* c0 * 0.5 + c1 * T_raw / kT °C
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*
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* TODO:
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* - Optionally support the FIFO
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*/
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#include <linux/i2c.h>
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2019-05-21 02:13:34 +00:00
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#include <linux/limits.h>
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#include <linux/math64.h>
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2019-05-21 02:13:32 +00:00
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#include <linux/module.h>
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#include <linux/regmap.h>
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#include <linux/iio/iio.h>
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#include <linux/iio/sysfs.h>
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#define DPS310_DEV_NAME "dps310"
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#define DPS310_PRS_B0 0x00
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#define DPS310_PRS_B1 0x01
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#define DPS310_PRS_B2 0x02
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#define DPS310_TMP_B0 0x03
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#define DPS310_TMP_B1 0x04
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#define DPS310_TMP_B2 0x05
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#define DPS310_PRS_CFG 0x06
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2019-05-21 02:13:34 +00:00
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#define DPS310_PRS_RATE_BITS GENMASK(6, 4)
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#define DPS310_PRS_PRC_BITS GENMASK(3, 0)
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2019-05-21 02:13:32 +00:00
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#define DPS310_TMP_CFG 0x07
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#define DPS310_TMP_RATE_BITS GENMASK(6, 4)
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#define DPS310_TMP_PRC_BITS GENMASK(3, 0)
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#define DPS310_TMP_EXT BIT(7)
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#define DPS310_MEAS_CFG 0x08
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#define DPS310_MEAS_CTRL_BITS GENMASK(2, 0)
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#define DPS310_PRS_EN BIT(0)
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#define DPS310_TEMP_EN BIT(1)
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#define DPS310_BACKGROUND BIT(2)
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#define DPS310_PRS_RDY BIT(4)
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#define DPS310_TMP_RDY BIT(5)
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#define DPS310_SENSOR_RDY BIT(6)
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#define DPS310_COEF_RDY BIT(7)
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#define DPS310_CFG_REG 0x09
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#define DPS310_INT_HL BIT(7)
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#define DPS310_TMP_SHIFT_EN BIT(3)
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#define DPS310_PRS_SHIFT_EN BIT(4)
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#define DPS310_FIFO_EN BIT(5)
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#define DPS310_SPI_EN BIT(6)
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#define DPS310_RESET 0x0c
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#define DPS310_RESET_MAGIC 0x09
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#define DPS310_COEF_BASE 0x10
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/* Make sure sleep time is <= 20ms for usleep_range */
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#define DPS310_POLL_SLEEP_US(t) min(20000, (t) / 8)
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/* Silently handle error in rate value here */
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#define DPS310_POLL_TIMEOUT_US(rc) ((rc) <= 0 ? 1000000 : 1000000 / (rc))
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#define DPS310_PRS_BASE DPS310_PRS_B0
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#define DPS310_TMP_BASE DPS310_TMP_B0
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/*
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* These values (defined in the spec) indicate how to scale the raw register
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* values for each level of precision available.
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*/
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static const int scale_factors[] = {
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524288,
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1572864,
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3670016,
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7864320,
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253952,
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516096,
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1040384,
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2088960,
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};
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struct dps310_data {
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struct i2c_client *client;
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struct regmap *regmap;
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struct mutex lock; /* Lock for sequential HW access functions */
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s32 c0, c1;
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2019-05-21 02:13:34 +00:00
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s32 c00, c10, c20, c30, c01, c11, c21;
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s32 pressure_raw;
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2019-05-21 02:13:32 +00:00
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s32 temp_raw;
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};
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static const struct iio_chan_spec dps310_channels[] = {
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{
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.type = IIO_TEMP,
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.info_mask_separate = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) |
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BIT(IIO_CHAN_INFO_SAMP_FREQ) |
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BIT(IIO_CHAN_INFO_PROCESSED),
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},
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2019-05-21 02:13:34 +00:00
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{
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.type = IIO_PRESSURE,
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.info_mask_separate = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) |
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BIT(IIO_CHAN_INFO_SAMP_FREQ) |
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BIT(IIO_CHAN_INFO_PROCESSED),
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},
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2019-05-21 02:13:32 +00:00
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};
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/* To be called after checking the COEF_RDY bit in MEAS_CFG */
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2019-05-21 02:13:34 +00:00
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static int dps310_get_coefs(struct dps310_data *data)
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2019-05-21 02:13:32 +00:00
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{
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int rc;
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2019-05-21 02:13:34 +00:00
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u8 coef[18];
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2019-05-21 02:13:32 +00:00
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u32 c0, c1;
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2019-05-21 02:13:34 +00:00
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u32 c00, c10, c20, c30, c01, c11, c21;
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2019-05-21 02:13:32 +00:00
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2019-05-21 02:13:34 +00:00
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/* Read all sensor calibration coefficients from the COEF registers. */
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2019-05-21 02:13:32 +00:00
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rc = regmap_bulk_read(data->regmap, DPS310_COEF_BASE, coef,
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sizeof(coef));
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if (rc < 0)
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return rc;
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2019-05-21 02:13:34 +00:00
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/*
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* Calculate temperature calibration coefficients c0 and c1. The
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* numbers are 12-bit 2's complement numbers.
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*/
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2019-05-21 02:13:32 +00:00
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c0 = (coef[0] << 4) | (coef[1] >> 4);
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data->c0 = sign_extend32(c0, 11);
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c1 = ((coef[1] & GENMASK(3, 0)) << 8) | coef[2];
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data->c1 = sign_extend32(c1, 11);
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2019-05-21 02:13:34 +00:00
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/*
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* Calculate pressure calibration coefficients. c00 and c10 are 20 bit
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* 2's complement numbers, while the rest are 16 bit 2's complement
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* numbers.
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*/
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c00 = (coef[3] << 12) | (coef[4] << 4) | (coef[5] >> 4);
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data->c00 = sign_extend32(c00, 19);
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c10 = ((coef[5] & GENMASK(3, 0)) << 16) | (coef[6] << 8) | coef[7];
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data->c10 = sign_extend32(c10, 19);
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c01 = (coef[8] << 8) | coef[9];
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data->c01 = sign_extend32(c01, 15);
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c11 = (coef[10] << 8) | coef[11];
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data->c11 = sign_extend32(c11, 15);
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c20 = (coef[12] << 8) | coef[13];
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data->c20 = sign_extend32(c20, 15);
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c21 = (coef[14] << 8) | coef[15];
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data->c21 = sign_extend32(c21, 15);
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c30 = (coef[16] << 8) | coef[17];
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data->c30 = sign_extend32(c30, 15);
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2019-05-21 02:13:32 +00:00
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return 0;
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}
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2019-05-21 02:13:34 +00:00
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static int dps310_get_pres_precision(struct dps310_data *data)
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{
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int rc;
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int val;
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rc = regmap_read(data->regmap, DPS310_PRS_CFG, &val);
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if (rc < 0)
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return rc;
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return BIT(val & GENMASK(2, 0));
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}
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2019-05-21 02:13:32 +00:00
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static int dps310_get_temp_precision(struct dps310_data *data)
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{
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int rc;
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int val;
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rc = regmap_read(data->regmap, DPS310_TMP_CFG, &val);
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if (rc < 0)
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return rc;
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/*
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* Scale factor is bottom 4 bits of the register, but 1111 is
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* reserved so just grab bottom three
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*/
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return BIT(val & GENMASK(2, 0));
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}
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2019-05-21 02:13:34 +00:00
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/* Called with lock held */
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static int dps310_set_pres_precision(struct dps310_data *data, int val)
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{
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int rc;
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u8 shift_en;
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if (val < 0 || val > 128)
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return -EINVAL;
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shift_en = val >= 16 ? DPS310_PRS_SHIFT_EN : 0;
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rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
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DPS310_PRS_SHIFT_EN, shift_en);
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if (rc)
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return rc;
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return regmap_update_bits(data->regmap, DPS310_PRS_CFG,
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DPS310_PRS_PRC_BITS, ilog2(val));
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}
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2019-05-21 02:13:32 +00:00
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/* Called with lock held */
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static int dps310_set_temp_precision(struct dps310_data *data, int val)
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{
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int rc;
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u8 shift_en;
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if (val < 0 || val > 128)
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return -EINVAL;
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shift_en = val >= 16 ? DPS310_TMP_SHIFT_EN : 0;
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rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
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DPS310_TMP_SHIFT_EN, shift_en);
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if (rc)
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return rc;
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return regmap_update_bits(data->regmap, DPS310_TMP_CFG,
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DPS310_TMP_PRC_BITS, ilog2(val));
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}
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2019-05-21 02:13:34 +00:00
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/* Called with lock held */
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static int dps310_set_pres_samp_freq(struct dps310_data *data, int freq)
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{
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u8 val;
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if (freq < 0 || freq > 128)
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return -EINVAL;
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val = ilog2(freq) << 4;
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return regmap_update_bits(data->regmap, DPS310_PRS_CFG,
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DPS310_PRS_RATE_BITS, val);
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}
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2019-05-21 02:13:32 +00:00
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/* Called with lock held */
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static int dps310_set_temp_samp_freq(struct dps310_data *data, int freq)
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{
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u8 val;
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if (freq < 0 || freq > 128)
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return -EINVAL;
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val = ilog2(freq) << 4;
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return regmap_update_bits(data->regmap, DPS310_TMP_CFG,
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DPS310_TMP_RATE_BITS, val);
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}
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2019-05-21 02:13:34 +00:00
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static int dps310_get_pres_samp_freq(struct dps310_data *data)
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{
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int rc;
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int val;
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rc = regmap_read(data->regmap, DPS310_PRS_CFG, &val);
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if (rc < 0)
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return rc;
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return BIT((val & DPS310_PRS_RATE_BITS) >> 4);
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}
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2019-05-21 02:13:32 +00:00
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static int dps310_get_temp_samp_freq(struct dps310_data *data)
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{
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int rc;
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int val;
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rc = regmap_read(data->regmap, DPS310_TMP_CFG, &val);
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if (rc < 0)
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return rc;
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return BIT((val & DPS310_TMP_RATE_BITS) >> 4);
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}
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2019-05-21 02:13:34 +00:00
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static int dps310_get_pres_k(struct dps310_data *data)
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{
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int rc = dps310_get_pres_precision(data);
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if (rc < 0)
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return rc;
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return scale_factors[ilog2(rc)];
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}
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2019-05-21 02:13:32 +00:00
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static int dps310_get_temp_k(struct dps310_data *data)
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{
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int rc = dps310_get_temp_precision(data);
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if (rc < 0)
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return rc;
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return scale_factors[ilog2(rc)];
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}
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2019-05-21 02:13:34 +00:00
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static int dps310_read_pres_raw(struct dps310_data *data)
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2019-05-21 02:13:32 +00:00
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{
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int rc;
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int rate;
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int ready;
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int timeout;
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s32 raw;
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u8 val[3];
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if (mutex_lock_interruptible(&data->lock))
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return -EINTR;
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2019-05-21 02:13:34 +00:00
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rate = dps310_get_pres_samp_freq(data);
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2019-05-21 02:13:32 +00:00
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timeout = DPS310_POLL_TIMEOUT_US(rate);
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/* Poll for sensor readiness; base the timeout upon the sample rate. */
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rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready,
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2019-05-21 02:13:34 +00:00
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ready & DPS310_PRS_RDY,
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2019-05-21 02:13:32 +00:00
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DPS310_POLL_SLEEP_US(timeout), timeout);
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2019-05-21 02:13:34 +00:00
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if (rc)
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goto done;
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rc = regmap_bulk_read(data->regmap, DPS310_PRS_BASE, val, sizeof(val));
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2019-05-21 02:13:32 +00:00
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if (rc < 0)
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goto done;
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2019-05-21 02:13:34 +00:00
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raw = (val[0] << 16) | (val[1] << 8) | val[2];
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data->pressure_raw = sign_extend32(raw, 23);
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done:
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mutex_unlock(&data->lock);
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return rc;
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}
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/* Called with lock held */
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static int dps310_read_temp_ready(struct dps310_data *data)
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{
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int rc;
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u8 val[3];
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s32 raw;
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2019-05-21 02:13:32 +00:00
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|
|
rc = regmap_bulk_read(data->regmap, DPS310_TMP_BASE, val, sizeof(val));
|
|
|
|
if (rc < 0)
|
2019-05-21 02:13:34 +00:00
|
|
|
return rc;
|
2019-05-21 02:13:32 +00:00
|
|
|
|
|
|
|
raw = (val[0] << 16) | (val[1] << 8) | val[2];
|
|
|
|
data->temp_raw = sign_extend32(raw, 23);
|
|
|
|
|
2019-05-21 02:13:34 +00:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int dps310_read_temp_raw(struct dps310_data *data)
|
|
|
|
{
|
|
|
|
int rc;
|
|
|
|
int rate;
|
|
|
|
int ready;
|
|
|
|
int timeout;
|
|
|
|
|
|
|
|
if (mutex_lock_interruptible(&data->lock))
|
|
|
|
return -EINTR;
|
|
|
|
|
|
|
|
rate = dps310_get_temp_samp_freq(data);
|
|
|
|
timeout = DPS310_POLL_TIMEOUT_US(rate);
|
|
|
|
|
|
|
|
/* Poll for sensor readiness; base the timeout upon the sample rate. */
|
|
|
|
rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready,
|
|
|
|
ready & DPS310_TMP_RDY,
|
|
|
|
DPS310_POLL_SLEEP_US(timeout), timeout);
|
|
|
|
if (rc < 0)
|
|
|
|
goto done;
|
|
|
|
|
|
|
|
rc = dps310_read_temp_ready(data);
|
|
|
|
|
2019-05-21 02:13:32 +00:00
|
|
|
done:
|
|
|
|
mutex_unlock(&data->lock);
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
|
|
|
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:
|
2019-05-21 02:13:33 +00:00
|
|
|
/* No documentation available on the registers below */
|
|
|
|
case 0x0e:
|
|
|
|
case 0x0f:
|
|
|
|
case 0x62:
|
2019-05-21 02:13:32 +00:00
|
|
|
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:
|
2019-05-21 02:13:33 +00:00
|
|
|
case 0x32: /* No documentation available on this register */
|
2019-05-21 02:13:32 +00:00
|
|
|
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)
|
|
|
|
{
|
|
|
|
int rc;
|
|
|
|
struct dps310_data *data = iio_priv(iio);
|
|
|
|
|
|
|
|
if (mutex_lock_interruptible(&data->lock))
|
|
|
|
return -EINTR;
|
|
|
|
|
|
|
|
switch (mask) {
|
|
|
|
case IIO_CHAN_INFO_SAMP_FREQ:
|
2019-05-21 02:13:34 +00:00
|
|
|
switch (chan->type) {
|
|
|
|
case IIO_PRESSURE:
|
|
|
|
rc = dps310_set_pres_samp_freq(data, val);
|
|
|
|
break;
|
|
|
|
|
|
|
|
case IIO_TEMP:
|
|
|
|
rc = dps310_set_temp_samp_freq(data, val);
|
|
|
|
break;
|
|
|
|
|
|
|
|
default:
|
|
|
|
rc = -EINVAL;
|
|
|
|
break;
|
|
|
|
}
|
2019-05-21 02:13:32 +00:00
|
|
|
break;
|
|
|
|
|
|
|
|
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
|
2019-05-21 02:13:34 +00:00
|
|
|
switch (chan->type) {
|
|
|
|
case IIO_PRESSURE:
|
|
|
|
rc = dps310_set_pres_precision(data, val);
|
|
|
|
break;
|
|
|
|
|
|
|
|
case IIO_TEMP:
|
|
|
|
rc = dps310_set_temp_precision(data, val);
|
|
|
|
break;
|
|
|
|
|
|
|
|
default:
|
|
|
|
rc = -EINVAL;
|
|
|
|
break;
|
|
|
|
}
|
2019-05-21 02:13:32 +00:00
|
|
|
break;
|
|
|
|
|
|
|
|
default:
|
|
|
|
rc = -EINVAL;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
mutex_unlock(&data->lock);
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
|
2019-05-21 02:13:34 +00:00
|
|
|
static int dps310_calculate_pressure(struct dps310_data *data)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
int rc;
|
|
|
|
int t_ready;
|
|
|
|
int kpi = dps310_get_pres_k(data);
|
|
|
|
int kti = dps310_get_temp_k(data);
|
|
|
|
s64 rem = 0ULL;
|
|
|
|
s64 pressure = 0ULL;
|
|
|
|
s64 p;
|
|
|
|
s64 t;
|
|
|
|
s64 denoms[7];
|
|
|
|
s64 nums[7];
|
|
|
|
s64 rems[7];
|
|
|
|
s64 kp;
|
|
|
|
s64 kt;
|
|
|
|
|
|
|
|
if (kpi < 0)
|
|
|
|
return kpi;
|
|
|
|
|
|
|
|
if (kti < 0)
|
|
|
|
return kti;
|
|
|
|
|
|
|
|
kp = (s64)kpi;
|
|
|
|
kt = (s64)kti;
|
|
|
|
|
|
|
|
/* Refresh temp if it's ready, otherwise just use the latest value */
|
|
|
|
if (mutex_trylock(&data->lock)) {
|
|
|
|
rc = regmap_read(data->regmap, DPS310_MEAS_CFG, &t_ready);
|
|
|
|
if (rc >= 0 && t_ready & DPS310_TMP_RDY)
|
|
|
|
dps310_read_temp_ready(data);
|
|
|
|
|
|
|
|
mutex_unlock(&data->lock);
|
|
|
|
}
|
|
|
|
|
|
|
|
p = (s64)data->pressure_raw;
|
|
|
|
t = (s64)data->temp_raw;
|
|
|
|
|
|
|
|
/* Section 4.9.1 of the DPS310 spec; algebra'd to avoid underflow */
|
|
|
|
nums[0] = (s64)data->c00;
|
|
|
|
denoms[0] = 1LL;
|
|
|
|
nums[1] = p * (s64)data->c10;
|
|
|
|
denoms[1] = kp;
|
|
|
|
nums[2] = p * p * (s64)data->c20;
|
|
|
|
denoms[2] = kp * kp;
|
|
|
|
nums[3] = p * p * p * (s64)data->c30;
|
|
|
|
denoms[3] = kp * kp * kp;
|
|
|
|
nums[4] = t * (s64)data->c01;
|
|
|
|
denoms[4] = kt;
|
|
|
|
nums[5] = t * p * (s64)data->c11;
|
|
|
|
denoms[5] = kp * kt;
|
|
|
|
nums[6] = t * p * p * (s64)data->c21;
|
|
|
|
denoms[6] = kp * kp * kt;
|
|
|
|
|
|
|
|
/* Kernel lacks a div64_s64_rem function; denoms are all positive */
|
|
|
|
for (i = 0; i < 7; ++i) {
|
|
|
|
u64 irem;
|
|
|
|
|
|
|
|
if (nums[i] < 0LL) {
|
|
|
|
pressure -= div64_u64_rem(-nums[i], denoms[i], &irem);
|
|
|
|
rems[i] = -irem;
|
|
|
|
} else {
|
|
|
|
pressure += div64_u64_rem(nums[i], denoms[i], &irem);
|
|
|
|
rems[i] = (s64)irem;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Increase precision and calculate the remainder sum */
|
|
|
|
for (i = 0; i < 7; ++i)
|
|
|
|
rem += div64_s64((s64)rems[i] * 1000000000LL, denoms[i]);
|
|
|
|
|
|
|
|
pressure += div_s64(rem, 1000000000LL);
|
|
|
|
if (pressure < 0LL)
|
|
|
|
return -ERANGE;
|
|
|
|
|
|
|
|
return (int)min_t(s64, pressure, INT_MAX);
|
|
|
|
}
|
|
|
|
|
|
|
|
static int dps310_read_pressure(struct dps310_data *data, int *val, int *val2,
|
|
|
|
long mask)
|
|
|
|
{
|
|
|
|
int rc;
|
|
|
|
|
|
|
|
switch (mask) {
|
|
|
|
case IIO_CHAN_INFO_SAMP_FREQ:
|
|
|
|
rc = dps310_get_pres_samp_freq(data);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
*val = rc;
|
|
|
|
return IIO_VAL_INT;
|
|
|
|
|
|
|
|
case IIO_CHAN_INFO_PROCESSED:
|
|
|
|
rc = dps310_read_pres_raw(data);
|
|
|
|
if (rc)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
rc = dps310_calculate_pressure(data);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
*val = rc;
|
|
|
|
*val2 = 1000; /* Convert Pa to KPa per IIO ABI */
|
|
|
|
return IIO_VAL_FRACTIONAL;
|
|
|
|
|
|
|
|
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
|
|
|
|
rc = dps310_get_pres_precision(data);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
*val = rc;
|
|
|
|
return IIO_VAL_INT;
|
|
|
|
|
|
|
|
default:
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2019-05-21 02:13:32 +00:00
|
|
|
static int dps310_calculate_temp(struct dps310_data *data)
|
|
|
|
{
|
|
|
|
s64 c0;
|
|
|
|
s64 t;
|
|
|
|
int kt = dps310_get_temp_k(data);
|
|
|
|
|
|
|
|
if (kt < 0)
|
|
|
|
return kt;
|
|
|
|
|
|
|
|
/* Obtain inverse-scaled offset */
|
|
|
|
c0 = div_s64((s64)kt * (s64)data->c0, 2);
|
|
|
|
|
|
|
|
/* Add the offset to the unscaled temperature */
|
|
|
|
t = c0 + ((s64)data->temp_raw * (s64)data->c1);
|
|
|
|
|
|
|
|
/* Convert to milliCelsius and scale the temperature */
|
|
|
|
return (int)div_s64(t * 1000LL, kt);
|
|
|
|
}
|
|
|
|
|
2019-05-21 02:13:34 +00:00
|
|
|
static int dps310_read_temp(struct dps310_data *data, int *val, int *val2,
|
|
|
|
long mask)
|
2019-05-21 02:13:32 +00:00
|
|
|
{
|
|
|
|
int rc;
|
|
|
|
|
|
|
|
switch (mask) {
|
|
|
|
case IIO_CHAN_INFO_SAMP_FREQ:
|
|
|
|
rc = dps310_get_temp_samp_freq(data);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
*val = rc;
|
|
|
|
return IIO_VAL_INT;
|
|
|
|
|
|
|
|
case IIO_CHAN_INFO_PROCESSED:
|
2019-05-21 02:13:34 +00:00
|
|
|
rc = dps310_read_temp_raw(data);
|
2019-05-21 02:13:32 +00:00
|
|
|
if (rc)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
rc = dps310_calculate_temp(data);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
*val = rc;
|
|
|
|
return IIO_VAL_INT;
|
|
|
|
|
|
|
|
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
|
|
|
|
rc = dps310_get_temp_precision(data);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
*val = rc;
|
|
|
|
return IIO_VAL_INT;
|
|
|
|
|
|
|
|
default:
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2019-05-21 02:13:34 +00:00
|
|
|
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);
|
|
|
|
|
|
|
|
switch (chan->type) {
|
|
|
|
case IIO_PRESSURE:
|
|
|
|
return dps310_read_pressure(data, val, val2, mask);
|
|
|
|
|
|
|
|
case IIO_TEMP:
|
|
|
|
return dps310_read_temp(data, val, val2, mask);
|
|
|
|
|
|
|
|
default:
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2019-05-21 02:13:32 +00:00
|
|
|
static void dps310_reset(void *action_data)
|
|
|
|
{
|
|
|
|
struct dps310_data *data = action_data;
|
|
|
|
|
|
|
|
regmap_write(data->regmap, DPS310_RESET, DPS310_RESET_MAGIC);
|
|
|
|
}
|
|
|
|
|
|
|
|
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,
|
2019-05-21 02:13:33 +00:00
|
|
|
.max_register = 0x62, /* No documentation available on this register */
|
2019-05-21 02:13:32 +00:00
|
|
|
};
|
|
|
|
|
|
|
|
static const struct iio_info dps310_info = {
|
|
|
|
.read_raw = dps310_read_raw,
|
|
|
|
.write_raw = dps310_write_raw,
|
|
|
|
};
|
|
|
|
|
2019-05-21 02:13:33 +00:00
|
|
|
/*
|
|
|
|
* Some verions of chip will read temperatures in the ~60C range when
|
|
|
|
* its actually ~20C. This is the manufacturer recommended workaround
|
|
|
|
* to correct the issue. The registers used below are undocumented.
|
|
|
|
*/
|
|
|
|
static int dps310_temp_workaround(struct dps310_data *data)
|
|
|
|
{
|
|
|
|
int rc;
|
|
|
|
int reg;
|
|
|
|
|
|
|
|
rc = regmap_read(data->regmap, 0x32, ®);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If bit 1 is set then the device is okay, and the workaround does not
|
|
|
|
* need to be applied
|
|
|
|
*/
|
|
|
|
if (reg & BIT(1))
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
rc = regmap_write(data->regmap, 0x0e, 0xA5);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
rc = regmap_write(data->regmap, 0x0f, 0x96);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
rc = regmap_write(data->regmap, 0x62, 0x02);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
rc = regmap_write(data->regmap, 0x0e, 0x00);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
return regmap_write(data->regmap, 0x0f, 0x00);
|
|
|
|
}
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|
|
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2019-05-21 02:13:32 +00:00
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|
static int dps310_probe(struct i2c_client *client,
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|
|
|
const struct i2c_device_id *id)
|
|
|
|
{
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|
|
|
struct dps310_data *data;
|
|
|
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struct iio_dev *iio;
|
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|
|
int rc, ready;
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|
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|
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iio = devm_iio_device_alloc(&client->dev, sizeof(*data));
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|
|
if (!iio)
|
|
|
|
return -ENOMEM;
|
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|
|
|
|
|
|
data = iio_priv(iio);
|
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|
|
data->client = client;
|
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|
|
mutex_init(&data->lock);
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|
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|
|
iio->name = id->name;
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|
|
iio->channels = dps310_channels;
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|
|
iio->num_channels = ARRAY_SIZE(dps310_channels);
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|
|
iio->info = &dps310_info;
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|
|
iio->modes = INDIO_DIRECT_MODE;
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|
|
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|
|
data->regmap = devm_regmap_init_i2c(client, &dps310_regmap_config);
|
|
|
|
if (IS_ERR(data->regmap))
|
|
|
|
return PTR_ERR(data->regmap);
|
|
|
|
|
|
|
|
/* Register to run the device reset when the device is removed */
|
|
|
|
rc = devm_add_action_or_reset(&client->dev, dps310_reset, data);
|
|
|
|
if (rc)
|
|
|
|
return rc;
|
|
|
|
|
2019-05-21 02:13:34 +00:00
|
|
|
/*
|
|
|
|
* Set up pressure sensor in single sample, one measurement per second
|
|
|
|
* mode
|
|
|
|
*/
|
|
|
|
rc = regmap_write(data->regmap, DPS310_PRS_CFG, 0);
|
|
|
|
|
2019-05-21 02:13:32 +00:00
|
|
|
/*
|
|
|
|
* Set up external (MEMS) temperature sensor in single sample, one
|
|
|
|
* measurement per second mode
|
|
|
|
*/
|
|
|
|
rc = regmap_write(data->regmap, DPS310_TMP_CFG, DPS310_TMP_EXT);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
2019-05-21 02:13:34 +00:00
|
|
|
/* Temp and pressure shifts are disabled when PRC <= 8 */
|
2019-05-21 02:13:32 +00:00
|
|
|
rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
|
2019-05-21 02:13:34 +00:00
|
|
|
DPS310_PRS_SHIFT_EN | DPS310_TMP_SHIFT_EN, 0);
|
2019-05-21 02:13:32 +00:00
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
/* MEAS_CFG doesn't update correctly unless first written with 0 */
|
|
|
|
rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG,
|
|
|
|
DPS310_MEAS_CTRL_BITS, 0);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
2019-05-21 02:13:34 +00:00
|
|
|
/* Turn on temperature and pressure measurement in the background */
|
2019-05-21 02:13:32 +00:00
|
|
|
rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG,
|
2019-05-21 02:13:34 +00:00
|
|
|
DPS310_MEAS_CTRL_BITS, DPS310_PRS_EN |
|
2019-05-21 02:13:32 +00:00
|
|
|
DPS310_TEMP_EN | DPS310_BACKGROUND);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Calibration coefficients required for reporting temperature.
|
|
|
|
* They are available 40ms after the device has started
|
|
|
|
*/
|
|
|
|
rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready,
|
|
|
|
ready & DPS310_COEF_RDY, 10000, 40000);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
2019-05-21 02:13:34 +00:00
|
|
|
rc = dps310_get_coefs(data);
|
2019-05-21 02:13:32 +00:00
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
2019-05-21 02:13:33 +00:00
|
|
|
rc = dps310_temp_workaround(data);
|
|
|
|
if (rc < 0)
|
|
|
|
return rc;
|
|
|
|
|
2019-05-21 02:13:32 +00:00
|
|
|
rc = devm_iio_device_register(&client->dev, iio);
|
|
|
|
if (rc)
|
|
|
|
return rc;
|
|
|
|
|
|
|
|
i2c_set_clientdata(client, iio);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct i2c_device_id dps310_id[] = {
|
|
|
|
{ DPS310_DEV_NAME, 0 },
|
|
|
|
{}
|
|
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(i2c, dps310_id);
|
|
|
|
|
|
|
|
static struct i2c_driver dps310_driver = {
|
|
|
|
.driver = {
|
|
|
|
.name = DPS310_DEV_NAME,
|
|
|
|
},
|
|
|
|
.probe = dps310_probe,
|
|
|
|
.id_table = dps310_id,
|
|
|
|
};
|
|
|
|
module_i2c_driver(dps310_driver);
|
|
|
|
|
|
|
|
MODULE_AUTHOR("Joel Stanley <joel@jms.id.au>");
|
|
|
|
MODULE_DESCRIPTION("Infineon DPS310 pressure and temperature sensor");
|
|
|
|
MODULE_LICENSE("GPL v2");
|