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linux-zen-server/drivers/iio/pressure/bmp280-core.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2010 Christoph Mair <christoph.mair@gmail.com>
* Copyright (c) 2012 Bosch Sensortec GmbH
* Copyright (c) 2012 Unixphere AB
* Copyright (c) 2014 Intel Corporation
* Copyright (c) 2016 Linus Walleij <linus.walleij@linaro.org>
*
* Driver for Bosch Sensortec BMP180 and BMP280 digital pressure sensor.
*
* Datasheet:
* https://cdn-shop.adafruit.com/datasheets/BST-BMP180-DS000-09.pdf
* https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bmp280-ds001.pdf
* https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bme280-ds002.pdf
* https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bmp388-ds001.pdf
*
* Notice:
* The link to the bmp180 datasheet points to an outdated version missing these changes:
* - Changed document referral from ANP015 to BST-MPS-AN004-00 on page 26
* - Updated equation for B3 param on section 3.5 to ((((long)AC1 * 4 + X3) << oss) + 2) / 4
* - Updated RoHS directive to 2011/65/EU effective 8 June 2011 on page 26
*/
#define pr_fmt(fmt) "bmp280: " fmt
#include <linux/bitops.h>
#include <linux/bitfield.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/delay.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/gpio/consumer.h>
#include <linux/regulator/consumer.h>
#include <linux/interrupt.h>
#include <linux/irq.h> /* For irq_get_irq_data() */
#include <linux/completion.h>
#include <linux/pm_runtime.h>
#include <linux/random.h>
#include <asm/unaligned.h>
#include "bmp280.h"
/*
* These enums are used for indexing into the array of calibration
* coefficients for BMP180.
*/
enum { AC1, AC2, AC3, AC4, AC5, AC6, B1, B2, MB, MC, MD };
struct bmp180_calib {
s16 AC1;
s16 AC2;
s16 AC3;
u16 AC4;
u16 AC5;
u16 AC6;
s16 B1;
s16 B2;
s16 MB;
s16 MC;
s16 MD;
};
/* See datasheet Section 4.2.2. */
struct bmp280_calib {
u16 T1;
s16 T2;
s16 T3;
u16 P1;
s16 P2;
s16 P3;
s16 P4;
s16 P5;
s16 P6;
s16 P7;
s16 P8;
s16 P9;
u8 H1;
s16 H2;
u8 H3;
s16 H4;
s16 H5;
s8 H6;
};
/* See datasheet Section 3.11.1. */
struct bmp380_calib {
u16 T1;
u16 T2;
s8 T3;
s16 P1;
s16 P2;
s8 P3;
s8 P4;
u16 P5;
u16 P6;
s8 P7;
s8 P8;
s16 P9;
s8 P10;
s8 P11;
};
static const char *const bmp280_supply_names[] = {
"vddd", "vdda"
};
#define BMP280_NUM_SUPPLIES ARRAY_SIZE(bmp280_supply_names)
enum bmp380_odr {
BMP380_ODR_200HZ,
BMP380_ODR_100HZ,
BMP380_ODR_50HZ,
BMP380_ODR_25HZ,
BMP380_ODR_12_5HZ,
BMP380_ODR_6_25HZ,
BMP380_ODR_3_125HZ,
BMP380_ODR_1_5625HZ,
BMP380_ODR_0_78HZ,
BMP380_ODR_0_39HZ,
BMP380_ODR_0_2HZ,
BMP380_ODR_0_1HZ,
BMP380_ODR_0_05HZ,
BMP380_ODR_0_02HZ,
BMP380_ODR_0_01HZ,
BMP380_ODR_0_006HZ,
BMP380_ODR_0_003HZ,
BMP380_ODR_0_0015HZ,
};
struct bmp280_data {
struct device *dev;
struct mutex lock;
struct regmap *regmap;
struct completion done;
bool use_eoc;
const struct bmp280_chip_info *chip_info;
union {
struct bmp180_calib bmp180;
struct bmp280_calib bmp280;
struct bmp380_calib bmp380;
} calib;
struct regulator_bulk_data supplies[BMP280_NUM_SUPPLIES];
unsigned int start_up_time; /* in microseconds */
/* log of base 2 of oversampling rate */
u8 oversampling_press;
u8 oversampling_temp;
u8 oversampling_humid;
u8 iir_filter_coeff;
/*
* BMP380 devices introduce sampling frequency configuration. See
* datasheet sections 3.3.3. and 4.3.19 for more details.
*
* BMx280 devices allowed indirect configuration of sampling frequency
* changing the t_standby duration between measurements, as detailed on
* section 3.6.3 of the datasheet.
*/
int sampling_freq;
/*
* Carryover value from temperature conversion, used in pressure
* calculation.
*/
s32 t_fine;
/*
* DMA (thus cache coherency maintenance) may require the
* transfer buffers to live in their own cache lines.
*/
union {
/* Sensor data buffer */
u8 buf[3];
/* Calibration data buffers */
__le16 bmp280_cal_buf[BMP280_CONTIGUOUS_CALIB_REGS / 2];
__be16 bmp180_cal_buf[BMP180_REG_CALIB_COUNT / 2];
u8 bmp380_cal_buf[BMP380_CALIB_REG_COUNT];
/* Miscellaneous, endianess-aware data buffers */
__le16 le16;
__be16 be16;
} __aligned(IIO_DMA_MINALIGN);
};
struct bmp280_chip_info {
unsigned int id_reg;
const struct iio_chan_spec *channels;
int num_channels;
unsigned int start_up_time;
const int *oversampling_temp_avail;
int num_oversampling_temp_avail;
int oversampling_temp_default;
const int *oversampling_press_avail;
int num_oversampling_press_avail;
int oversampling_press_default;
const int *oversampling_humid_avail;
int num_oversampling_humid_avail;
int oversampling_humid_default;
const int *iir_filter_coeffs_avail;
int num_iir_filter_coeffs_avail;
int iir_filter_coeff_default;
const int (*sampling_freq_avail)[2];
int num_sampling_freq_avail;
int sampling_freq_default;
int (*chip_config)(struct bmp280_data *);
int (*read_temp)(struct bmp280_data *, int *);
int (*read_press)(struct bmp280_data *, int *, int *);
int (*read_humid)(struct bmp280_data *, int *, int *);
int (*read_calib)(struct bmp280_data *);
};
/*
* These enums are used for indexing into the array of compensation
* parameters for BMP280.
*/
enum { T1, T2, T3, P1, P2, P3, P4, P5, P6, P7, P8, P9 };
enum {
/* Temperature calib indexes */
BMP380_T1 = 0,
BMP380_T2 = 2,
BMP380_T3 = 4,
/* Pressure calib indexes */
BMP380_P1 = 5,
BMP380_P2 = 7,
BMP380_P3 = 9,
BMP380_P4 = 10,
BMP380_P5 = 11,
BMP380_P6 = 13,
BMP380_P7 = 15,
BMP380_P8 = 16,
BMP380_P9 = 17,
BMP380_P10 = 19,
BMP380_P11 = 20,
};
static const struct iio_chan_spec bmp280_channels[] = {
{
.type = IIO_PRESSURE,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
},
{
.type = IIO_TEMP,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
},
{
.type = IIO_HUMIDITYRELATIVE,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
},
};
static const struct iio_chan_spec bmp380_channels[] = {
{
.type = IIO_PRESSURE,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
},
{
.type = IIO_TEMP,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
},
{
.type = IIO_HUMIDITYRELATIVE,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
},
};
static int bmp280_read_calib(struct bmp280_data *data)
{
struct bmp280_calib *calib = &data->calib.bmp280;
int ret;
/* Read temperature and pressure calibration values. */
ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
data->bmp280_cal_buf, sizeof(data->bmp280_cal_buf));
if (ret < 0) {
dev_err(data->dev,
"failed to read temperature and pressure calibration parameters\n");
return ret;
}
/* Toss the temperature and pressure calibration data into the entropy pool */
add_device_randomness(data->bmp280_cal_buf, sizeof(data->bmp280_cal_buf));
/* Parse temperature calibration values. */
calib->T1 = le16_to_cpu(data->bmp280_cal_buf[T1]);
calib->T2 = le16_to_cpu(data->bmp280_cal_buf[T2]);
calib->T3 = le16_to_cpu(data->bmp280_cal_buf[T3]);
/* Parse pressure calibration values. */
calib->P1 = le16_to_cpu(data->bmp280_cal_buf[P1]);
calib->P2 = le16_to_cpu(data->bmp280_cal_buf[P2]);
calib->P3 = le16_to_cpu(data->bmp280_cal_buf[P3]);
calib->P4 = le16_to_cpu(data->bmp280_cal_buf[P4]);
calib->P5 = le16_to_cpu(data->bmp280_cal_buf[P5]);
calib->P6 = le16_to_cpu(data->bmp280_cal_buf[P6]);
calib->P7 = le16_to_cpu(data->bmp280_cal_buf[P7]);
calib->P8 = le16_to_cpu(data->bmp280_cal_buf[P8]);
calib->P9 = le16_to_cpu(data->bmp280_cal_buf[P9]);
return 0;
}
static int bme280_read_calib(struct bmp280_data *data)
{
struct bmp280_calib *calib = &data->calib.bmp280;
struct device *dev = data->dev;
unsigned int tmp;
int ret;
/* Load shared calibration params with bmp280 first */
ret = bmp280_read_calib(data);
if (ret < 0) {
dev_err(dev, "failed to read common bmp280 calibration parameters\n");
return ret;
}
/*
* Read humidity calibration values.
* Due to some odd register addressing we cannot just
* do a big bulk read. Instead, we have to read each Hx
* value separately and sometimes do some bit shifting...
* Humidity data is only available on BME280.
*/
ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &tmp);
if (ret < 0) {
dev_err(dev, "failed to read H1 comp value\n");
return ret;
}
calib->H1 = tmp;
ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2,
&data->le16, sizeof(data->le16));
if (ret < 0) {
dev_err(dev, "failed to read H2 comp value\n");
return ret;
}
calib->H2 = sign_extend32(le16_to_cpu(data->le16), 15);
ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &tmp);
if (ret < 0) {
dev_err(dev, "failed to read H3 comp value\n");
return ret;
}
calib->H3 = tmp;
ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4,
&data->be16, sizeof(data->be16));
if (ret < 0) {
dev_err(dev, "failed to read H4 comp value\n");
return ret;
}
calib->H4 = sign_extend32(((be16_to_cpu(data->be16) >> 4) & 0xff0) |
(be16_to_cpu(data->be16) & 0xf), 11);
ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H5,
&data->le16, sizeof(data->le16));
if (ret < 0) {
dev_err(dev, "failed to read H5 comp value\n");
return ret;
}
calib->H5 = sign_extend32(FIELD_GET(BMP280_COMP_H5_MASK, le16_to_cpu(data->le16)), 11);
ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp);
if (ret < 0) {
dev_err(dev, "failed to read H6 comp value\n");
return ret;
}
calib->H6 = sign_extend32(tmp, 7);
return 0;
}
/*
* Returns humidity in percent, resolution is 0.01 percent. Output value of
* "47445" represents 47445/1024 = 46.333 %RH.
*
* Taken from BME280 datasheet, Section 4.2.3, "Compensation formula".
*/
static u32 bmp280_compensate_humidity(struct bmp280_data *data,
s32 adc_humidity)
{
struct bmp280_calib *calib = &data->calib.bmp280;
s32 var;
var = ((s32)data->t_fine) - (s32)76800;
var = ((((adc_humidity << 14) - (calib->H4 << 20) - (calib->H5 * var))
+ (s32)16384) >> 15) * (((((((var * calib->H6) >> 10)
* (((var * (s32)calib->H3) >> 11) + (s32)32768)) >> 10)
+ (s32)2097152) * calib->H2 + 8192) >> 14);
var -= ((((var >> 15) * (var >> 15)) >> 7) * (s32)calib->H1) >> 4;
var = clamp_val(var, 0, 419430400);
return var >> 12;
};
/*
* Returns temperature in DegC, resolution is 0.01 DegC. Output value of
* "5123" equals 51.23 DegC. t_fine carries fine temperature as global
* value.
*
* Taken from datasheet, Section 3.11.3, "Compensation formula".
*/
static s32 bmp280_compensate_temp(struct bmp280_data *data,
s32 adc_temp)
{
struct bmp280_calib *calib = &data->calib.bmp280;
s32 var1, var2;
var1 = (((adc_temp >> 3) - ((s32)calib->T1 << 1)) *
((s32)calib->T2)) >> 11;
var2 = (((((adc_temp >> 4) - ((s32)calib->T1)) *
((adc_temp >> 4) - ((s32)calib->T1))) >> 12) *
((s32)calib->T3)) >> 14;
data->t_fine = var1 + var2;
return (data->t_fine * 5 + 128) >> 8;
}
/*
* Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24
* integer bits and 8 fractional bits). Output value of "24674867"
* represents 24674867/256 = 96386.2 Pa = 963.862 hPa
*
* Taken from datasheet, Section 3.11.3, "Compensation formula".
*/
static u32 bmp280_compensate_press(struct bmp280_data *data,
s32 adc_press)
{
struct bmp280_calib *calib = &data->calib.bmp280;
s64 var1, var2, p;
var1 = ((s64)data->t_fine) - 128000;
var2 = var1 * var1 * (s64)calib->P6;
var2 += (var1 * (s64)calib->P5) << 17;
var2 += ((s64)calib->P4) << 35;
var1 = ((var1 * var1 * (s64)calib->P3) >> 8) +
((var1 * (s64)calib->P2) << 12);
var1 = ((((s64)1) << 47) + var1) * ((s64)calib->P1) >> 33;
if (var1 == 0)
return 0;
p = ((((s64)1048576 - adc_press) << 31) - var2) * 3125;
p = div64_s64(p, var1);
var1 = (((s64)calib->P9) * (p >> 13) * (p >> 13)) >> 25;
var2 = ((s64)(calib->P8) * p) >> 19;
p = ((p + var1 + var2) >> 8) + (((s64)calib->P7) << 4);
return (u32)p;
}
static int bmp280_read_temp(struct bmp280_data *data,
int *val)
{
s32 adc_temp, comp_temp;
int ret;
ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB,
data->buf, sizeof(data->buf));
if (ret < 0) {
dev_err(data->dev, "failed to read temperature\n");
return ret;
}
adc_temp = FIELD_GET(BMP280_MEAS_TRIM_MASK, get_unaligned_be24(data->buf));
if (adc_temp == BMP280_TEMP_SKIPPED) {
/* reading was skipped */
dev_err(data->dev, "reading temperature skipped\n");
return -EIO;
}
comp_temp = bmp280_compensate_temp(data, adc_temp);
/*
* val might be NULL if we're called by the read_press routine,
* who only cares about the carry over t_fine value.
*/
if (val) {
*val = comp_temp * 10;
return IIO_VAL_INT;
}
return 0;
}
static int bmp280_read_press(struct bmp280_data *data,
int *val, int *val2)
{
u32 comp_press;
s32 adc_press;
int ret;
/* Read and compensate temperature so we get a reading of t_fine. */
ret = bmp280_read_temp(data, NULL);
if (ret < 0)
return ret;
ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB,
data->buf, sizeof(data->buf));
if (ret < 0) {
dev_err(data->dev, "failed to read pressure\n");
return ret;
}
adc_press = FIELD_GET(BMP280_MEAS_TRIM_MASK, get_unaligned_be24(data->buf));
if (adc_press == BMP280_PRESS_SKIPPED) {
/* reading was skipped */
dev_err(data->dev, "reading pressure skipped\n");
return -EIO;
}
comp_press = bmp280_compensate_press(data, adc_press);
*val = comp_press;
*val2 = 256000;
return IIO_VAL_FRACTIONAL;
}
static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
{
u32 comp_humidity;
s32 adc_humidity;
int ret;
/* Read and compensate temperature so we get a reading of t_fine. */
ret = bmp280_read_temp(data, NULL);
if (ret < 0)
return ret;
ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB,
&data->be16, sizeof(data->be16));
if (ret < 0) {
dev_err(data->dev, "failed to read humidity\n");
return ret;
}
adc_humidity = be16_to_cpu(data->be16);
if (adc_humidity == BMP280_HUMIDITY_SKIPPED) {
/* reading was skipped */
dev_err(data->dev, "reading humidity skipped\n");
return -EIO;
}
comp_humidity = bmp280_compensate_humidity(data, adc_humidity);
*val = comp_humidity * 1000 / 1024;
return IIO_VAL_INT;
}
static int bmp280_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct bmp280_data *data = iio_priv(indio_dev);
int ret;
pm_runtime_get_sync(data->dev);
mutex_lock(&data->lock);
switch (mask) {
case IIO_CHAN_INFO_PROCESSED:
switch (chan->type) {
case IIO_HUMIDITYRELATIVE:
ret = data->chip_info->read_humid(data, val, val2);
break;
case IIO_PRESSURE:
ret = data->chip_info->read_press(data, val, val2);
break;
case IIO_TEMP:
ret = data->chip_info->read_temp(data, val);
break;
default:
ret = -EINVAL;
break;
}
break;
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
switch (chan->type) {
case IIO_HUMIDITYRELATIVE:
*val = 1 << data->oversampling_humid;
ret = IIO_VAL_INT;
break;
case IIO_PRESSURE:
*val = 1 << data->oversampling_press;
ret = IIO_VAL_INT;
break;
case IIO_TEMP:
*val = 1 << data->oversampling_temp;
ret = IIO_VAL_INT;
break;
default:
ret = -EINVAL;
break;
}
break;
case IIO_CHAN_INFO_SAMP_FREQ:
if (!data->chip_info->sampling_freq_avail) {
ret = -EINVAL;
break;
}
*val = data->chip_info->sampling_freq_avail[data->sampling_freq][0];
*val2 = data->chip_info->sampling_freq_avail[data->sampling_freq][1];
ret = IIO_VAL_INT_PLUS_MICRO;
break;
case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
if (!data->chip_info->iir_filter_coeffs_avail) {
ret = -EINVAL;
break;
}
*val = (1 << data->iir_filter_coeff) - 1;
ret = IIO_VAL_INT;
break;
default:
ret = -EINVAL;
break;
}
mutex_unlock(&data->lock);
pm_runtime_mark_last_busy(data->dev);
pm_runtime_put_autosuspend(data->dev);
return ret;
}
static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data,
int val)
{
const int *avail = data->chip_info->oversampling_humid_avail;
const int n = data->chip_info->num_oversampling_humid_avail;
int ret, prev;
int i;
for (i = 0; i < n; i++) {
if (avail[i] == val) {
prev = data->oversampling_humid;
data->oversampling_humid = ilog2(val);
ret = data->chip_info->chip_config(data);
if (ret) {
data->oversampling_humid = prev;
data->chip_info->chip_config(data);
return ret;
}
return 0;
}
}
return -EINVAL;
}
static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data,
int val)
{
const int *avail = data->chip_info->oversampling_temp_avail;
const int n = data->chip_info->num_oversampling_temp_avail;
int ret, prev;
int i;
for (i = 0; i < n; i++) {
if (avail[i] == val) {
prev = data->oversampling_temp;
data->oversampling_temp = ilog2(val);
ret = data->chip_info->chip_config(data);
if (ret) {
data->oversampling_temp = prev;
data->chip_info->chip_config(data);
return ret;
}
return 0;
}
}
return -EINVAL;
}
static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data,
int val)
{
const int *avail = data->chip_info->oversampling_press_avail;
const int n = data->chip_info->num_oversampling_press_avail;
int ret, prev;
int i;
for (i = 0; i < n; i++) {
if (avail[i] == val) {
prev = data->oversampling_press;
data->oversampling_press = ilog2(val);
ret = data->chip_info->chip_config(data);
if (ret) {
data->oversampling_press = prev;
data->chip_info->chip_config(data);
return ret;
}
return 0;
}
}
return -EINVAL;
}
static int bmp280_write_sampling_frequency(struct bmp280_data *data,
int val, int val2)
{
const int (*avail)[2] = data->chip_info->sampling_freq_avail;
const int n = data->chip_info->num_sampling_freq_avail;
int ret, prev;
int i;
for (i = 0; i < n; i++) {
if (avail[i][0] == val && avail[i][1] == val2) {
prev = data->sampling_freq;
data->sampling_freq = i;
ret = data->chip_info->chip_config(data);
if (ret) {
data->sampling_freq = prev;
data->chip_info->chip_config(data);
return ret;
}
return 0;
}
}
return -EINVAL;
}
static int bmp280_write_iir_filter_coeffs(struct bmp280_data *data, int val)
{
const int *avail = data->chip_info->iir_filter_coeffs_avail;
const int n = data->chip_info->num_iir_filter_coeffs_avail;
int ret, prev;
int i;
for (i = 0; i < n; i++) {
if (avail[i] - 1 == val) {
prev = data->iir_filter_coeff;
data->iir_filter_coeff = i;
ret = data->chip_info->chip_config(data);
if (ret) {
data->iir_filter_coeff = prev;
data->chip_info->chip_config(data);
return ret;
}
return 0;
}
}
return -EINVAL;
}
static int bmp280_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct bmp280_data *data = iio_priv(indio_dev);
int ret = 0;
/*
* Helper functions to update sensor running configuration.
* If an error happens applying new settings, will try restore
* previous parameters to ensure the sensor is left in a known
* working configuration.
*/
switch (mask) {
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
pm_runtime_get_sync(data->dev);
mutex_lock(&data->lock);
switch (chan->type) {
case IIO_HUMIDITYRELATIVE:
ret = bmp280_write_oversampling_ratio_humid(data, val);
break;
case IIO_PRESSURE:
ret = bmp280_write_oversampling_ratio_press(data, val);
break;
case IIO_TEMP:
ret = bmp280_write_oversampling_ratio_temp(data, val);
break;
default:
ret = -EINVAL;
break;
}
mutex_unlock(&data->lock);
pm_runtime_mark_last_busy(data->dev);
pm_runtime_put_autosuspend(data->dev);
break;
case IIO_CHAN_INFO_SAMP_FREQ:
pm_runtime_get_sync(data->dev);
mutex_lock(&data->lock);
ret = bmp280_write_sampling_frequency(data, val, val2);
mutex_unlock(&data->lock);
pm_runtime_mark_last_busy(data->dev);
pm_runtime_put_autosuspend(data->dev);
break;
case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
pm_runtime_get_sync(data->dev);
mutex_lock(&data->lock);
ret = bmp280_write_iir_filter_coeffs(data, val);
mutex_unlock(&data->lock);
pm_runtime_mark_last_busy(data->dev);
pm_runtime_put_autosuspend(data->dev);
break;
default:
return -EINVAL;
}
return ret;
}
static int bmp280_read_avail(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
const int **vals, int *type, int *length,
long mask)
{
struct bmp280_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
switch (chan->type) {
case IIO_PRESSURE:
*vals = data->chip_info->oversampling_press_avail;
*length = data->chip_info->num_oversampling_press_avail;
break;
case IIO_TEMP:
*vals = data->chip_info->oversampling_temp_avail;
*length = data->chip_info->num_oversampling_temp_avail;
break;
default:
return -EINVAL;
}
*type = IIO_VAL_INT;
return IIO_AVAIL_LIST;
case IIO_CHAN_INFO_SAMP_FREQ:
*vals = (const int *)data->chip_info->sampling_freq_avail;
*type = IIO_VAL_INT_PLUS_MICRO;
/* Values are stored in a 2D matrix */
*length = data->chip_info->num_sampling_freq_avail;
return IIO_AVAIL_LIST;
case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
*vals = data->chip_info->iir_filter_coeffs_avail;
*type = IIO_VAL_INT;
*length = data->chip_info->num_iir_filter_coeffs_avail;
return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
}
static const struct iio_info bmp280_info = {
.read_raw = &bmp280_read_raw,
.read_avail = &bmp280_read_avail,
.write_raw = &bmp280_write_raw,
};
static int bmp280_chip_config(struct bmp280_data *data)
{
u8 osrs = FIELD_PREP(BMP280_OSRS_TEMP_MASK, data->oversampling_temp + 1) |
FIELD_PREP(BMP280_OSRS_PRESS_MASK, data->oversampling_press + 1);
int ret;
ret = regmap_write_bits(data->regmap, BMP280_REG_CTRL_MEAS,
BMP280_OSRS_TEMP_MASK |
BMP280_OSRS_PRESS_MASK |
BMP280_MODE_MASK,
osrs | BMP280_MODE_NORMAL);
if (ret < 0) {
dev_err(data->dev,
"failed to write ctrl_meas register\n");
return ret;
}
ret = regmap_update_bits(data->regmap, BMP280_REG_CONFIG,
BMP280_FILTER_MASK,
BMP280_FILTER_4X);
if (ret < 0) {
dev_err(data->dev,
"failed to write config register\n");
return ret;
}
return ret;
}
static const int bmp280_oversampling_avail[] = { 1, 2, 4, 8, 16 };
static const struct bmp280_chip_info bmp280_chip_info = {
.id_reg = BMP280_REG_ID,
.start_up_time = 2000,
.channels = bmp280_channels,
.num_channels = 2,
.oversampling_temp_avail = bmp280_oversampling_avail,
.num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
/*
* Oversampling config values on BMx280 have one additional setting
* that other generations of the family don't:
* The value 0 means the measurement is bypassed instead of
* oversampling set to x1.
*
* To account for this difference, and preserve the same common
* config logic, this is handled later on chip_config callback
* incrementing one unit the oversampling setting.
*/
.oversampling_temp_default = BMP280_OSRS_TEMP_2X - 1,
.oversampling_press_avail = bmp280_oversampling_avail,
.num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
.oversampling_press_default = BMP280_OSRS_PRESS_16X - 1,
.chip_config = bmp280_chip_config,
.read_temp = bmp280_read_temp,
.read_press = bmp280_read_press,
.read_calib = bmp280_read_calib,
};
static int bme280_chip_config(struct bmp280_data *data)
{
u8 osrs = FIELD_PREP(BMP280_OSRS_HUMIDITY_MASK, data->oversampling_humid + 1);
int ret;
/*
* Oversampling of humidity must be set before oversampling of
* temperature/pressure is set to become effective.
*/
ret = regmap_update_bits(data->regmap, BMP280_REG_CTRL_HUMIDITY,
BMP280_OSRS_HUMIDITY_MASK, osrs);
if (ret < 0)
return ret;
return bmp280_chip_config(data);
}
static const struct bmp280_chip_info bme280_chip_info = {
.id_reg = BMP280_REG_ID,
.start_up_time = 2000,
.channels = bmp280_channels,
.num_channels = 3,
.oversampling_temp_avail = bmp280_oversampling_avail,
.num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
.oversampling_temp_default = BMP280_OSRS_TEMP_2X - 1,
.oversampling_press_avail = bmp280_oversampling_avail,
.num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
.oversampling_press_default = BMP280_OSRS_PRESS_16X - 1,
.oversampling_humid_avail = bmp280_oversampling_avail,
.num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail),
.oversampling_humid_default = BMP280_OSRS_HUMIDITY_16X - 1,
.chip_config = bme280_chip_config,
.read_temp = bmp280_read_temp,
.read_press = bmp280_read_press,
.read_humid = bmp280_read_humid,
.read_calib = bme280_read_calib,
};
/*
* Helper function to send a command to BMP3XX sensors.
*
* Sensor processes commands written to the CMD register and signals
* execution result through "cmd_rdy" and "cmd_error" flags available on
* STATUS and ERROR registers.
*/
static int bmp380_cmd(struct bmp280_data *data, u8 cmd)
{
unsigned int reg;
int ret;
/* Check if device is ready to process a command */
ret = regmap_read(data->regmap, BMP380_REG_STATUS, &reg);
if (ret) {
dev_err(data->dev, "failed to read error register\n");
return ret;
}
if (!(reg & BMP380_STATUS_CMD_RDY_MASK)) {
dev_err(data->dev, "device is not ready to accept commands\n");
return -EBUSY;
}
/* Send command to process */
ret = regmap_write(data->regmap, BMP380_REG_CMD, cmd);
if (ret) {
dev_err(data->dev, "failed to send command to device\n");
return ret;
}
/* Wait for 2ms for command to be processed */
usleep_range(data->start_up_time, data->start_up_time + 100);
/* Check for command processing error */
ret = regmap_read(data->regmap, BMP380_REG_ERROR, &reg);
if (ret) {
dev_err(data->dev, "error reading ERROR reg\n");
return ret;
}
if (reg & BMP380_ERR_CMD_MASK) {
dev_err(data->dev, "error processing command 0x%X\n", cmd);
return -EINVAL;
}
return 0;
}
/*
* Returns temperature in Celsius dregrees, resolution is 0.01º C. Output value of
* "5123" equals 51.2º C. t_fine carries fine temperature as global value.
*
* Taken from datasheet, Section Appendix 9, "Compensation formula" and repo
* https://github.com/BoschSensortec/BMP3-Sensor-API.
*/
static s32 bmp380_compensate_temp(struct bmp280_data *data, u32 adc_temp)
{
s64 var1, var2, var3, var4, var5, var6, comp_temp;
struct bmp380_calib *calib = &data->calib.bmp380;
var1 = ((s64) adc_temp) - (((s64) calib->T1) << 8);
var2 = var1 * ((s64) calib->T2);
var3 = var1 * var1;
var4 = var3 * ((s64) calib->T3);
var5 = (var2 << 18) + var4;
var6 = var5 >> 32;
data->t_fine = (s32) var6;
comp_temp = (var6 * 25) >> 14;
comp_temp = clamp_val(comp_temp, BMP380_MIN_TEMP, BMP380_MAX_TEMP);
return (s32) comp_temp;
}
/*
* Returns pressure in Pa as an unsigned 32 bit integer in fractional Pascal.
* Output value of "9528709" represents 9528709/100 = 95287.09 Pa = 952.8709 hPa.
*
* Taken from datasheet, Section 9.3. "Pressure compensation" and repository
* https://github.com/BoschSensortec/BMP3-Sensor-API.
*/
static u32 bmp380_compensate_press(struct bmp280_data *data, u32 adc_press)
{
s64 var1, var2, var3, var4, var5, var6, offset, sensitivity;
struct bmp380_calib *calib = &data->calib.bmp380;
u32 comp_press;
var1 = (s64)data->t_fine * (s64)data->t_fine;
var2 = var1 >> 6;
var3 = (var2 * ((s64) data->t_fine)) >> 8;
var4 = ((s64)calib->P8 * var3) >> 5;
var5 = ((s64)calib->P7 * var1) << 4;
var6 = ((s64)calib->P6 * (s64)data->t_fine) << 22;
offset = ((s64)calib->P5 << 47) + var4 + var5 + var6;
var2 = ((s64)calib->P4 * var3) >> 5;
var4 = ((s64)calib->P3 * var1) << 2;
var5 = ((s64)calib->P2 - ((s64)1 << 14)) *
((s64)data->t_fine << 21);
sensitivity = (((s64) calib->P1 - ((s64) 1 << 14)) << 46) +
var2 + var4 + var5;
var1 = (sensitivity >> 24) * (s64)adc_press;
var2 = (s64)calib->P10 * (s64)data->t_fine;
var3 = var2 + ((s64)calib->P9 << 16);
var4 = (var3 * (s64)adc_press) >> 13;
/*
* Dividing by 10 followed by multiplying by 10 to avoid
* possible overflow caused by (uncomp_data->pressure * partial_data4).
*/
var5 = ((s64)adc_press * div_s64(var4, 10)) >> 9;
var5 *= 10;
var6 = (s64)adc_press * (s64)adc_press;
var2 = ((s64)calib->P11 * var6) >> 16;
var3 = (var2 * (s64)adc_press) >> 7;
var4 = (offset >> 2) + var1 + var5 + var3;
comp_press = ((u64)var4 * 25) >> 40;
comp_press = clamp_val(comp_press, BMP380_MIN_PRES, BMP380_MAX_PRES);
return comp_press;
}
static int bmp380_read_temp(struct bmp280_data *data, int *val)
{
s32 comp_temp;
u32 adc_temp;
int ret;
ret = regmap_bulk_read(data->regmap, BMP380_REG_TEMP_XLSB,
data->buf, sizeof(data->buf));
if (ret) {
dev_err(data->dev, "failed to read temperature\n");
return ret;
}
adc_temp = get_unaligned_le24(data->buf);
if (adc_temp == BMP380_TEMP_SKIPPED) {
dev_err(data->dev, "reading temperature skipped\n");
return -EIO;
}
comp_temp = bmp380_compensate_temp(data, adc_temp);
/*
* Val might be NULL if we're called by the read_press routine,
* who only cares about the carry over t_fine value.
*/
if (val) {
/* IIO reports temperatures in milli Celsius */
*val = comp_temp * 10;
return IIO_VAL_INT;
}
return 0;
}
static int bmp380_read_press(struct bmp280_data *data, int *val, int *val2)
{
s32 comp_press;
u32 adc_press;
int ret;
/* Read and compensate for temperature so we get a reading of t_fine */
ret = bmp380_read_temp(data, NULL);
if (ret)
return ret;
ret = regmap_bulk_read(data->regmap, BMP380_REG_PRESS_XLSB,
data->buf, sizeof(data->buf));
if (ret) {
dev_err(data->dev, "failed to read pressure\n");
return ret;
}
adc_press = get_unaligned_le24(data->buf);
if (adc_press == BMP380_PRESS_SKIPPED) {
dev_err(data->dev, "reading pressure skipped\n");
return -EIO;
}
comp_press = bmp380_compensate_press(data, adc_press);
*val = comp_press;
/* Compensated pressure is in cPa (centipascals) */
*val2 = 100000;
return IIO_VAL_FRACTIONAL;
}
static int bmp380_read_calib(struct bmp280_data *data)
{
struct bmp380_calib *calib = &data->calib.bmp380;
int ret;
/* Read temperature and pressure calibration data */
ret = regmap_bulk_read(data->regmap, BMP380_REG_CALIB_TEMP_START,
data->bmp380_cal_buf, sizeof(data->bmp380_cal_buf));
if (ret) {
dev_err(data->dev,
"failed to read temperature calibration parameters\n");
return ret;
}
/* Toss the temperature calibration data into the entropy pool */
add_device_randomness(data->bmp380_cal_buf, sizeof(data->bmp380_cal_buf));
/* Parse calibration values */
calib->T1 = get_unaligned_le16(&data->bmp380_cal_buf[BMP380_T1]);
calib->T2 = get_unaligned_le16(&data->bmp380_cal_buf[BMP380_T2]);
calib->T3 = data->bmp380_cal_buf[BMP380_T3];
calib->P1 = get_unaligned_le16(&data->bmp380_cal_buf[BMP380_P1]);
calib->P2 = get_unaligned_le16(&data->bmp380_cal_buf[BMP380_P2]);
calib->P3 = data->bmp380_cal_buf[BMP380_P3];
calib->P4 = data->bmp380_cal_buf[BMP380_P4];
calib->P5 = get_unaligned_le16(&data->bmp380_cal_buf[BMP380_P5]);
calib->P6 = get_unaligned_le16(&data->bmp380_cal_buf[BMP380_P6]);
calib->P7 = data->bmp380_cal_buf[BMP380_P7];
calib->P8 = data->bmp380_cal_buf[BMP380_P8];
calib->P9 = get_unaligned_le16(&data->bmp380_cal_buf[BMP380_P9]);
calib->P10 = data->bmp380_cal_buf[BMP380_P10];
calib->P11 = data->bmp380_cal_buf[BMP380_P11];
return 0;
}
static const int bmp380_odr_table[][2] = {
[BMP380_ODR_200HZ] = {200, 0},
[BMP380_ODR_100HZ] = {100, 0},
[BMP380_ODR_50HZ] = {50, 0},
[BMP380_ODR_25HZ] = {25, 0},
[BMP380_ODR_12_5HZ] = {12, 500000},
[BMP380_ODR_6_25HZ] = {6, 250000},
[BMP380_ODR_3_125HZ] = {3, 125000},
[BMP380_ODR_1_5625HZ] = {1, 562500},
[BMP380_ODR_0_78HZ] = {0, 781250},
[BMP380_ODR_0_39HZ] = {0, 390625},
[BMP380_ODR_0_2HZ] = {0, 195313},
[BMP380_ODR_0_1HZ] = {0, 97656},
[BMP380_ODR_0_05HZ] = {0, 48828},
[BMP380_ODR_0_02HZ] = {0, 24414},
[BMP380_ODR_0_01HZ] = {0, 12207},
[BMP380_ODR_0_006HZ] = {0, 6104},
[BMP380_ODR_0_003HZ] = {0, 3052},
[BMP380_ODR_0_0015HZ] = {0, 1526},
};
static int bmp380_chip_config(struct bmp280_data *data)
{
bool change = false, aux;
unsigned int tmp;
u8 osrs;
int ret;
/* Configure power control register */
ret = regmap_update_bits(data->regmap, BMP380_REG_POWER_CONTROL,
BMP380_CTRL_SENSORS_MASK,
BMP380_CTRL_SENSORS_PRESS_EN |
BMP380_CTRL_SENSORS_TEMP_EN);
if (ret) {
dev_err(data->dev,
"failed to write operation control register\n");
return ret;
}
/* Configure oversampling */
osrs = FIELD_PREP(BMP380_OSRS_TEMP_MASK, data->oversampling_temp) |
FIELD_PREP(BMP380_OSRS_PRESS_MASK, data->oversampling_press);
ret = regmap_update_bits_check(data->regmap, BMP380_REG_OSR,
BMP380_OSRS_TEMP_MASK |
BMP380_OSRS_PRESS_MASK,
osrs, &aux);
if (ret) {
dev_err(data->dev, "failed to write oversampling register\n");
return ret;
}
change = change || aux;
/* Configure output data rate */
ret = regmap_update_bits_check(data->regmap, BMP380_REG_ODR,
BMP380_ODRS_MASK, data->sampling_freq, &aux);
if (ret) {
dev_err(data->dev, "failed to write ODR selection register\n");
return ret;
}
change = change || aux;
/* Set filter data */
ret = regmap_update_bits_check(data->regmap, BMP380_REG_CONFIG, BMP380_FILTER_MASK,
FIELD_PREP(BMP380_FILTER_MASK, data->iir_filter_coeff),
&aux);
if (ret) {
dev_err(data->dev, "failed to write config register\n");
return ret;
}
change = change || aux;
if (change) {
/*
* The configurations errors are detected on the fly during a measurement
* cycle. If the sampling frequency is too low, it's faster to reset
* the measurement loop than wait until the next measurement is due.
*
* Resets sensor measurement loop toggling between sleep and normal
* operating modes.
*/
ret = regmap_write_bits(data->regmap, BMP380_REG_POWER_CONTROL,
BMP380_MODE_MASK,
FIELD_PREP(BMP380_MODE_MASK, BMP380_MODE_SLEEP));
if (ret) {
dev_err(data->dev, "failed to set sleep mode\n");
return ret;
}
usleep_range(2000, 2500);
ret = regmap_write_bits(data->regmap, BMP380_REG_POWER_CONTROL,
BMP380_MODE_MASK,
FIELD_PREP(BMP380_MODE_MASK, BMP380_MODE_NORMAL));
if (ret) {
dev_err(data->dev, "failed to set normal mode\n");
return ret;
}
/*
* Waits for measurement before checking configuration error flag.
* Selected longest measure time indicated in section 3.9.1
* in the datasheet.
*/
msleep(80);
/* Check config error flag */
ret = regmap_read(data->regmap, BMP380_REG_ERROR, &tmp);
if (ret) {
dev_err(data->dev,
"failed to read error register\n");
return ret;
}
if (tmp & BMP380_ERR_CONF_MASK) {
dev_warn(data->dev,
"sensor flagged configuration as incompatible\n");
return -EINVAL;
}
}
return 0;
}
static const int bmp380_oversampling_avail[] = { 1, 2, 4, 8, 16, 32 };
static const int bmp380_iir_filter_coeffs_avail[] = { 1, 2, 4, 8, 16, 32, 64, 128};
static const struct bmp280_chip_info bmp380_chip_info = {
.id_reg = BMP380_REG_ID,
.start_up_time = 2000,
.channels = bmp380_channels,
.num_channels = 2,
.oversampling_temp_avail = bmp380_oversampling_avail,
.num_oversampling_temp_avail = ARRAY_SIZE(bmp380_oversampling_avail),
.oversampling_temp_default = ilog2(1),
.oversampling_press_avail = bmp380_oversampling_avail,
.num_oversampling_press_avail = ARRAY_SIZE(bmp380_oversampling_avail),
.oversampling_press_default = ilog2(4),
.sampling_freq_avail = bmp380_odr_table,
.num_sampling_freq_avail = ARRAY_SIZE(bmp380_odr_table) * 2,
.sampling_freq_default = BMP380_ODR_50HZ,
.iir_filter_coeffs_avail = bmp380_iir_filter_coeffs_avail,
.num_iir_filter_coeffs_avail = ARRAY_SIZE(bmp380_iir_filter_coeffs_avail),
.iir_filter_coeff_default = 2,
.chip_config = bmp380_chip_config,
.read_temp = bmp380_read_temp,
.read_press = bmp380_read_press,
.read_calib = bmp380_read_calib,
};
static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
{
const int conversion_time_max[] = { 4500, 7500, 13500, 25500 };
unsigned int delay_us;
unsigned int ctrl;
int ret;
if (data->use_eoc)
reinit_completion(&data->done);
ret = regmap_write(data->regmap, BMP280_REG_CTRL_MEAS, ctrl_meas);
if (ret)
return ret;
if (data->use_eoc) {
/*
* If we have a completion interrupt, use it, wait up to
* 100ms. The longest conversion time listed is 76.5 ms for
* advanced resolution mode.
*/
ret = wait_for_completion_timeout(&data->done,
1 + msecs_to_jiffies(100));
if (!ret)
dev_err(data->dev, "timeout waiting for completion\n");
} else {
if (FIELD_GET(BMP180_MEAS_CTRL_MASK, ctrl_meas) == BMP180_MEAS_TEMP)
delay_us = 4500;
else
delay_us =
conversion_time_max[data->oversampling_press];
usleep_range(delay_us, delay_us + 1000);
}
ret = regmap_read(data->regmap, BMP280_REG_CTRL_MEAS, &ctrl);
if (ret)
return ret;
/* The value of this bit reset to "0" after conversion is complete */
if (ctrl & BMP180_MEAS_SCO)
return -EIO;
return 0;
}
static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
{
int ret;
ret = bmp180_measure(data,
FIELD_PREP(BMP180_MEAS_CTRL_MASK, BMP180_MEAS_TEMP) |
BMP180_MEAS_SCO);
if (ret)
return ret;
ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB,
&data->be16, sizeof(data->be16));
if (ret)
return ret;
*val = be16_to_cpu(data->be16);
return 0;
}
static int bmp180_read_calib(struct bmp280_data *data)
{
struct bmp180_calib *calib = &data->calib.bmp180;
int ret;
int i;
ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START,
data->bmp180_cal_buf, sizeof(data->bmp180_cal_buf));
if (ret < 0)
return ret;
/* None of the words has the value 0 or 0xFFFF */
for (i = 0; i < ARRAY_SIZE(data->bmp180_cal_buf); i++) {
if (data->bmp180_cal_buf[i] == cpu_to_be16(0) ||
data->bmp180_cal_buf[i] == cpu_to_be16(0xffff))
return -EIO;
}
/* Toss the calibration data into the entropy pool */
add_device_randomness(data->bmp180_cal_buf, sizeof(data->bmp180_cal_buf));
calib->AC1 = be16_to_cpu(data->bmp180_cal_buf[AC1]);
calib->AC2 = be16_to_cpu(data->bmp180_cal_buf[AC2]);
calib->AC3 = be16_to_cpu(data->bmp180_cal_buf[AC3]);
calib->AC4 = be16_to_cpu(data->bmp180_cal_buf[AC4]);
calib->AC5 = be16_to_cpu(data->bmp180_cal_buf[AC5]);
calib->AC6 = be16_to_cpu(data->bmp180_cal_buf[AC6]);
calib->B1 = be16_to_cpu(data->bmp180_cal_buf[B1]);
calib->B2 = be16_to_cpu(data->bmp180_cal_buf[B2]);
calib->MB = be16_to_cpu(data->bmp180_cal_buf[MB]);
calib->MC = be16_to_cpu(data->bmp180_cal_buf[MC]);
calib->MD = be16_to_cpu(data->bmp180_cal_buf[MD]);
return 0;
}
/*
* Returns temperature in DegC, resolution is 0.1 DegC.
* t_fine carries fine temperature as global value.
*
* Taken from datasheet, Section 3.5, "Calculating pressure and temperature".
*/
static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp)
{
struct bmp180_calib *calib = &data->calib.bmp180;
s32 x1, x2;
x1 = ((adc_temp - calib->AC6) * calib->AC5) >> 15;
x2 = (calib->MC << 11) / (x1 + calib->MD);
data->t_fine = x1 + x2;
return (data->t_fine + 8) >> 4;
}
static int bmp180_read_temp(struct bmp280_data *data, int *val)
{
s32 adc_temp, comp_temp;
int ret;
ret = bmp180_read_adc_temp(data, &adc_temp);
if (ret)
return ret;
comp_temp = bmp180_compensate_temp(data, adc_temp);
/*
* val might be NULL if we're called by the read_press routine,
* who only cares about the carry over t_fine value.
*/
if (val) {
*val = comp_temp * 100;
return IIO_VAL_INT;
}
return 0;
}
static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
{
u8 oss = data->oversampling_press;
int ret;
ret = bmp180_measure(data,
FIELD_PREP(BMP180_MEAS_CTRL_MASK, BMP180_MEAS_PRESS) |
FIELD_PREP(BMP180_OSRS_PRESS_MASK, oss) |
BMP180_MEAS_SCO);
if (ret)
return ret;
ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB,
data->buf, sizeof(data->buf));
if (ret)
return ret;
*val = get_unaligned_be24(data->buf) >> (8 - oss);
return 0;
}
/*
* Returns pressure in Pa, resolution is 1 Pa.
*
* Taken from datasheet, Section 3.5, "Calculating pressure and temperature".
*/
static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press)
{
struct bmp180_calib *calib = &data->calib.bmp180;
s32 oss = data->oversampling_press;
s32 x1, x2, x3, p;
s32 b3, b6;
u32 b4, b7;
b6 = data->t_fine - 4000;
x1 = (calib->B2 * (b6 * b6 >> 12)) >> 11;
x2 = calib->AC2 * b6 >> 11;
x3 = x1 + x2;
b3 = ((((s32)calib->AC1 * 4 + x3) << oss) + 2) / 4;
x1 = calib->AC3 * b6 >> 13;
x2 = (calib->B1 * ((b6 * b6) >> 12)) >> 16;
x3 = (x1 + x2 + 2) >> 2;
b4 = calib->AC4 * (u32)(x3 + 32768) >> 15;
b7 = ((u32)adc_press - b3) * (50000 >> oss);
if (b7 < 0x80000000)
p = (b7 * 2) / b4;
else
p = (b7 / b4) * 2;
x1 = (p >> 8) * (p >> 8);
x1 = (x1 * 3038) >> 16;
x2 = (-7357 * p) >> 16;
return p + ((x1 + x2 + 3791) >> 4);
}
static int bmp180_read_press(struct bmp280_data *data,
int *val, int *val2)
{
u32 comp_press;
s32 adc_press;
int ret;
/* Read and compensate temperature so we get a reading of t_fine. */
ret = bmp180_read_temp(data, NULL);
if (ret)
return ret;
ret = bmp180_read_adc_press(data, &adc_press);
if (ret)
return ret;
comp_press = bmp180_compensate_press(data, adc_press);
*val = comp_press;
*val2 = 1000;
return IIO_VAL_FRACTIONAL;
}
static int bmp180_chip_config(struct bmp280_data *data)
{
return 0;
}
static const int bmp180_oversampling_temp_avail[] = { 1 };
static const int bmp180_oversampling_press_avail[] = { 1, 2, 4, 8 };
static const struct bmp280_chip_info bmp180_chip_info = {
.id_reg = BMP280_REG_ID,
.start_up_time = 2000,
.channels = bmp280_channels,
.num_channels = 2,
.oversampling_temp_avail = bmp180_oversampling_temp_avail,
.num_oversampling_temp_avail =
ARRAY_SIZE(bmp180_oversampling_temp_avail),
.oversampling_temp_default = 0,
.oversampling_press_avail = bmp180_oversampling_press_avail,
.num_oversampling_press_avail =
ARRAY_SIZE(bmp180_oversampling_press_avail),
.oversampling_press_default = BMP180_MEAS_PRESS_8X,
.chip_config = bmp180_chip_config,
.read_temp = bmp180_read_temp,
.read_press = bmp180_read_press,
.read_calib = bmp180_read_calib,
};
static irqreturn_t bmp085_eoc_irq(int irq, void *d)
{
struct bmp280_data *data = d;
complete(&data->done);
return IRQ_HANDLED;
}
static int bmp085_fetch_eoc_irq(struct device *dev,
const char *name,
int irq,
struct bmp280_data *data)
{
unsigned long irq_trig;
int ret;
irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));
if (irq_trig != IRQF_TRIGGER_RISING) {
dev_err(dev, "non-rising trigger given for EOC interrupt, trying to enforce it\n");
irq_trig = IRQF_TRIGGER_RISING;
}
init_completion(&data->done);
ret = devm_request_threaded_irq(dev,
irq,
bmp085_eoc_irq,
NULL,
irq_trig,
name,
data);
if (ret) {
/* Bail out without IRQ but keep the driver in place */
dev_err(dev, "unable to request DRDY IRQ\n");
return 0;
}
data->use_eoc = true;
return 0;
}
static void bmp280_pm_disable(void *data)
{
struct device *dev = data;
pm_runtime_get_sync(dev);
pm_runtime_put_noidle(dev);
pm_runtime_disable(dev);
}
static void bmp280_regulators_disable(void *data)
{
struct regulator_bulk_data *supplies = data;
regulator_bulk_disable(BMP280_NUM_SUPPLIES, supplies);
}
int bmp280_common_probe(struct device *dev,
struct regmap *regmap,
unsigned int chip,
const char *name,
int irq)
{
const struct bmp280_chip_info *chip_info;
struct iio_dev *indio_dev;
struct bmp280_data *data;
struct gpio_desc *gpiod;
unsigned int chip_id;
int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
mutex_init(&data->lock);
data->dev = dev;
indio_dev->name = name;
indio_dev->info = &bmp280_info;
indio_dev->modes = INDIO_DIRECT_MODE;
switch (chip) {
case BMP180_CHIP_ID:
chip_info = &bmp180_chip_info;
break;
case BMP280_CHIP_ID:
chip_info = &bmp280_chip_info;
break;
case BME280_CHIP_ID:
chip_info = &bme280_chip_info;
break;
case BMP380_CHIP_ID:
chip_info = &bmp380_chip_info;
break;
default:
return -EINVAL;
}
data->chip_info = chip_info;
/* Apply initial values from chip info structure */
indio_dev->channels = chip_info->channels;
indio_dev->num_channels = chip_info->num_channels;
data->oversampling_press = chip_info->oversampling_press_default;
data->oversampling_humid = chip_info->oversampling_humid_default;
data->oversampling_temp = chip_info->oversampling_temp_default;
data->iir_filter_coeff = chip_info->iir_filter_coeff_default;
data->sampling_freq = chip_info->sampling_freq_default;
data->start_up_time = chip_info->start_up_time;
/* Bring up regulators */
regulator_bulk_set_supply_names(data->supplies,
bmp280_supply_names,
BMP280_NUM_SUPPLIES);
ret = devm_regulator_bulk_get(dev,
BMP280_NUM_SUPPLIES, data->supplies);
if (ret) {
dev_err(dev, "failed to get regulators\n");
return ret;
}
ret = regulator_bulk_enable(BMP280_NUM_SUPPLIES, data->supplies);
if (ret) {
dev_err(dev, "failed to enable regulators\n");
return ret;
}
ret = devm_add_action_or_reset(dev, bmp280_regulators_disable,
data->supplies);
if (ret)
return ret;
/* Wait to make sure we started up properly */
usleep_range(data->start_up_time, data->start_up_time + 100);
/* Bring chip out of reset if there is an assigned GPIO line */
gpiod = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
/* Deassert the signal */
if (gpiod) {
dev_info(dev, "release reset\n");
gpiod_set_value(gpiod, 0);
}
data->regmap = regmap;
ret = regmap_read(regmap, data->chip_info->id_reg, &chip_id);
if (ret < 0)
return ret;
if (chip_id != chip) {
dev_err(dev, "bad chip id: expected %x got %x\n",
chip, chip_id);
return -EINVAL;
}
/* BMP3xx requires soft-reset as part of initialization */
if (chip_id == BMP380_CHIP_ID) {
ret = bmp380_cmd(data, BMP380_CMD_SOFT_RESET);
if (ret < 0)
return ret;
}
ret = data->chip_info->chip_config(data);
if (ret < 0)
return ret;
dev_set_drvdata(dev, indio_dev);
/*
* Some chips have calibration parameters "programmed into the devices'
* non-volatile memory during production". Let's read them out at probe
* time once. They will not change.
*/
ret = data->chip_info->read_calib(data);
if (ret < 0)
return dev_err_probe(data->dev, ret,
"failed to read calibration coefficients\n");
/*
* Attempt to grab an optional EOC IRQ - only the BMP085 has this
* however as it happens, the BMP085 shares the chip ID of BMP180
* so we look for an IRQ if we have that.
*/
if (irq > 0 || (chip_id == BMP180_CHIP_ID)) {
ret = bmp085_fetch_eoc_irq(dev, name, irq, data);
if (ret)
return ret;
}
/* Enable runtime PM */
pm_runtime_get_noresume(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
/*
* Set autosuspend to two orders of magnitude larger than the
* start-up time.
*/
pm_runtime_set_autosuspend_delay(dev, data->start_up_time / 10);
pm_runtime_use_autosuspend(dev);
pm_runtime_put(dev);
ret = devm_add_action_or_reset(dev, bmp280_pm_disable, dev);
if (ret)
return ret;
return devm_iio_device_register(dev, indio_dev);
}
EXPORT_SYMBOL_NS(bmp280_common_probe, IIO_BMP280);
static int bmp280_runtime_suspend(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct bmp280_data *data = iio_priv(indio_dev);
return regulator_bulk_disable(BMP280_NUM_SUPPLIES, data->supplies);
}
static int bmp280_runtime_resume(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct bmp280_data *data = iio_priv(indio_dev);
int ret;
ret = regulator_bulk_enable(BMP280_NUM_SUPPLIES, data->supplies);
if (ret)
return ret;
usleep_range(data->start_up_time, data->start_up_time + 100);
return data->chip_info->chip_config(data);
}
EXPORT_RUNTIME_DEV_PM_OPS(bmp280_dev_pm_ops, bmp280_runtime_suspend,
bmp280_runtime_resume, NULL);
MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor");
MODULE_LICENSE("GPL v2");
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