901a293fd9
The DPS310 sensor chip has been encountering intermittent errors while
reading the sensor device across various system designs. This issue causes
the chip to become "stuck," preventing the indication of "ready" status
for pressure and temperature measurements in the MEAS_CFG register.
To address this issue, this commit fixes the timeout settings to improve
sensor stability:
- After sending a reset command to the chip, the timeout has been extended
from 2.5 ms to 15 ms, aligning with the DPS310 specification.
- The read timeout value of the MEAS_CFG register has been adjusted from
20ms to 30ms to match the specification.
Signed-off-by: Lakshmi Yadlapati <lakshmiy@us.ibm.com>
Fixes: 7b4ab4abce
("iio: pressure: dps310: Reset chip after timeout")
Link: https://lore.kernel.org/r/20230829180222.3431926-2-lakshmiy@us.ibm.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
898 lines
19 KiB
C
898 lines
19 KiB
C
// 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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#include <linux/limits.h>
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#include <linux/math64.h>
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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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#define DPS310_PRS_RATE_BITS GENMASK(6, 4)
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#define DPS310_PRS_PRC_BITS GENMASK(3, 0)
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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 <= 30ms for usleep_range */
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#define DPS310_POLL_SLEEP_US(t) min(30000, (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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s32 c00, c10, c20, c30, c01, c11, c21;
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s32 pressure_raw;
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s32 temp_raw;
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bool timeout_recovery_failed;
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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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{
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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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};
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/* To be called after checking the COEF_RDY bit in MEAS_CFG */
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static int dps310_get_coefs(struct dps310_data *data)
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{
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int rc;
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u8 coef[18];
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u32 c0, c1;
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u32 c00, c10, c20, c30, c01, c11, c21;
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/* Read all sensor calibration coefficients from the COEF registers. */
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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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/*
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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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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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/*
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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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return 0;
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}
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/*
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* Some versions of the chip will read temperatures in the ~60C range when
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* it's actually ~20C. This is the manufacturer recommended workaround
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* to correct the issue. The registers used below are undocumented.
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*/
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static int dps310_temp_workaround(struct dps310_data *data)
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{
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int rc;
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int reg;
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rc = regmap_read(data->regmap, 0x32, ®);
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if (rc)
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return rc;
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/*
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* If bit 1 is set then the device is okay, and the workaround does not
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* need to be applied
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*/
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if (reg & BIT(1))
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return 0;
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rc = regmap_write(data->regmap, 0x0e, 0xA5);
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if (rc)
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return rc;
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rc = regmap_write(data->regmap, 0x0f, 0x96);
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if (rc)
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return rc;
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rc = regmap_write(data->regmap, 0x62, 0x02);
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if (rc)
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return rc;
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rc = regmap_write(data->regmap, 0x0e, 0x00);
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if (rc)
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return rc;
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return regmap_write(data->regmap, 0x0f, 0x00);
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}
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static int dps310_startup(struct dps310_data *data)
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{
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int rc;
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int ready;
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/*
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* Set up pressure sensor in single sample, one measurement per second
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* mode
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*/
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rc = regmap_write(data->regmap, DPS310_PRS_CFG, 0);
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if (rc)
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return rc;
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/*
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* Set up external (MEMS) temperature sensor in single sample, one
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* measurement per second mode
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*/
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rc = regmap_write(data->regmap, DPS310_TMP_CFG, DPS310_TMP_EXT);
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if (rc)
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return rc;
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/* Temp and pressure shifts are disabled when PRC <= 8 */
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rc = regmap_write_bits(data->regmap, DPS310_CFG_REG,
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DPS310_PRS_SHIFT_EN | DPS310_TMP_SHIFT_EN, 0);
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if (rc)
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return rc;
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/* MEAS_CFG doesn't update correctly unless first written with 0 */
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rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG,
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DPS310_MEAS_CTRL_BITS, 0);
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if (rc)
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return rc;
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/* Turn on temperature and pressure measurement in the background */
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rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG,
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DPS310_MEAS_CTRL_BITS, DPS310_PRS_EN |
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DPS310_TEMP_EN | DPS310_BACKGROUND);
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if (rc)
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return rc;
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/*
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* Calibration coefficients required for reporting temperature.
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* They are available 40ms after the device has started
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*/
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rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready,
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ready & DPS310_COEF_RDY, 10000, 40000);
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if (rc)
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return rc;
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rc = dps310_get_coefs(data);
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if (rc)
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return rc;
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return dps310_temp_workaround(data);
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}
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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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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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/* 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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/* 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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/* 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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/* 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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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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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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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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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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static int dps310_reset_wait(struct dps310_data *data)
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{
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int rc;
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rc = regmap_write(data->regmap, DPS310_RESET, DPS310_RESET_MAGIC);
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if (rc)
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return rc;
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/* Wait for device chip access: 15ms in specification */
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usleep_range(15000, 55000);
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return 0;
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}
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static int dps310_reset_reinit(struct dps310_data *data)
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{
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int rc;
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rc = dps310_reset_wait(data);
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if (rc)
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return rc;
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return dps310_startup(data);
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}
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static int dps310_ready_status(struct dps310_data *data, int ready_bit, int timeout)
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{
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int sleep = DPS310_POLL_SLEEP_US(timeout);
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int ready;
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return regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, ready & ready_bit,
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sleep, timeout);
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}
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static int dps310_ready(struct dps310_data *data, int ready_bit, int timeout)
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{
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int rc;
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rc = dps310_ready_status(data, ready_bit, timeout);
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if (rc) {
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if (rc == -ETIMEDOUT && !data->timeout_recovery_failed) {
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/* Reset and reinitialize the chip. */
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if (dps310_reset_reinit(data)) {
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data->timeout_recovery_failed = true;
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} else {
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/* Try again to get sensor ready status. */
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if (dps310_ready_status(data, ready_bit, timeout))
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data->timeout_recovery_failed = true;
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else
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return 0;
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}
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}
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return rc;
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}
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data->timeout_recovery_failed = false;
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return 0;
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}
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static int dps310_read_pres_raw(struct dps310_data *data)
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{
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int rc;
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int rate;
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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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rate = dps310_get_pres_samp_freq(data);
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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 = dps310_ready(data, DPS310_PRS_RDY, timeout);
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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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if (rc < 0)
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goto done;
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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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rc = regmap_bulk_read(data->regmap, DPS310_TMP_BASE, val, sizeof(val));
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if (rc < 0)
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return rc;
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raw = (val[0] << 16) | (val[1] << 8) | val[2];
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data->temp_raw = sign_extend32(raw, 23);
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return 0;
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}
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static int dps310_read_temp_raw(struct dps310_data *data)
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|
{
|
|
int rc;
|
|
int rate;
|
|
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 = dps310_ready(data, DPS310_TMP_RDY, timeout);
|
|
if (rc)
|
|
goto done;
|
|
|
|
rc = dps310_read_temp_ready(data);
|
|
|
|
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:
|
|
/* No documentation available on the registers below */
|
|
case 0x0e:
|
|
case 0x0f:
|
|
case 0x62:
|
|
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:
|
|
case 0x32: /* No documentation available on this register */
|
|
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:
|
|
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;
|
|
}
|
|
break;
|
|
|
|
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
|
|
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;
|
|
}
|
|
break;
|
|
|
|
default:
|
|
rc = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
mutex_unlock(&data->lock);
|
|
return rc;
|
|
}
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
static int dps310_read_temp(struct dps310_data *data, int *val, int *val2,
|
|
long mask)
|
|
{
|
|
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:
|
|
rc = dps310_read_temp_raw(data);
|
|
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;
|
|
}
|
|
}
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
static void dps310_reset(void *action_data)
|
|
{
|
|
struct dps310_data *data = action_data;
|
|
|
|
dps310_reset_wait(data);
|
|
}
|
|
|
|
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 = 0x62, /* No documentation available on this register */
|
|
};
|
|
|
|
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 = i2c_client_get_device_id(client);
|
|
struct dps310_data *data;
|
|
struct iio_dev *iio;
|
|
int rc;
|
|
|
|
iio = devm_iio_device_alloc(&client->dev, sizeof(*data));
|
|
if (!iio)
|
|
return -ENOMEM;
|
|
|
|
data = iio_priv(iio);
|
|
data->client = client;
|
|
mutex_init(&data->lock);
|
|
|
|
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);
|
|
|
|
/* 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;
|
|
|
|
rc = dps310_startup(data);
|
|
if (rc)
|
|
return rc;
|
|
|
|
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 const struct acpi_device_id dps310_acpi_match[] = {
|
|
{ "IFX3100" },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(acpi, dps310_acpi_match);
|
|
|
|
static struct i2c_driver dps310_driver = {
|
|
.driver = {
|
|
.name = DPS310_DEV_NAME,
|
|
.acpi_match_table = dps310_acpi_match,
|
|
},
|
|
.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");
|