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

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/*
* 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.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Datasheet:
* https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP180-DS000-121.pdf
* https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BMP280-DS001-12.pdf
* https://ae-bst.resource.bosch.com/media/_tech/media/datasheets/BST-BME280_DS001-11.pdf
*/
#define pr_fmt(fmt) "bmp280: " fmt
#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 "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;
};
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;
struct bmp180_calib calib;
struct regulator *vddd;
struct regulator *vdda;
unsigned int start_up_time; /* in microseconds */
/* log of base 2 of oversampling rate */
u8 oversampling_press;
u8 oversampling_temp;
u8 oversampling_humid;
/*
* Carryover value from temperature conversion, used in pressure
* calculation.
*/
s32 t_fine;
};
struct bmp280_chip_info {
const int *oversampling_temp_avail;
int num_oversampling_temp_avail;
const int *oversampling_press_avail;
int num_oversampling_press_avail;
const int *oversampling_humid_avail;
int num_oversampling_humid_avail;
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 *);
};
/*
* These enums are used for indexing into the array of compensation
* parameters for BMP280.
*/
enum { T1, T2, T3 };
enum { P1, P2, P3, P4, P5, P6, P7, P8, P9 };
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),
},
};
/*
* 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 device *dev = data->dev;
unsigned int H1, H3, tmp;
int H2, H4, H5, H6, ret, var;
ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &H1);
if (ret < 0) {
dev_err(dev, "failed to read H1 comp value\n");
return ret;
}
ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &tmp, 2);
if (ret < 0) {
dev_err(dev, "failed to read H2 comp value\n");
return ret;
}
H2 = sign_extend32(le16_to_cpu(tmp), 15);
ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &H3);
if (ret < 0) {
dev_err(dev, "failed to read H3 comp value\n");
return ret;
}
ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &tmp, 2);
if (ret < 0) {
dev_err(dev, "failed to read H4 comp value\n");
return ret;
}
H4 = sign_extend32(((be16_to_cpu(tmp) >> 4) & 0xff0) |
(be16_to_cpu(tmp) & 0xf), 11);
ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H5, &tmp, 2);
if (ret < 0) {
dev_err(dev, "failed to read H5 comp value\n");
return ret;
}
H5 = sign_extend32(((le16_to_cpu(tmp) >> 4) & 0xfff), 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;
}
H6 = sign_extend32(tmp, 7);
var = ((s32)data->t_fine) - (s32)76800;
var = ((((adc_humidity << 14) - (H4 << 20) - (H5 * var))
+ (s32)16384) >> 15) * (((((((var * H6) >> 10)
* (((var * (s32)H3) >> 11) + (s32)32768)) >> 10)
+ (s32)2097152) * H2 + 8192) >> 14);
var -= ((((var >> 15) * (var >> 15)) >> 7) * (s32)H1) >> 4;
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)
{
int ret;
s32 var1, var2;
__le16 buf[BMP280_COMP_TEMP_REG_COUNT / 2];
ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
buf, BMP280_COMP_TEMP_REG_COUNT);
if (ret < 0) {
dev_err(data->dev,
"failed to read temperature calibration parameters\n");
return ret;
}
/*
* The double casts are necessary because le16_to_cpu returns an
* unsigned 16-bit value. Casting that value directly to a
* signed 32-bit will not do proper sign extension.
*
* Conversely, T1 and P1 are unsigned values, so they can be
* cast straight to the larger type.
*/
var1 = (((adc_temp >> 3) - ((s32)le16_to_cpu(buf[T1]) << 1)) *
((s32)(s16)le16_to_cpu(buf[T2]))) >> 11;
var2 = (((((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1]))) *
((adc_temp >> 4) - ((s32)le16_to_cpu(buf[T1])))) >> 12) *
((s32)(s16)le16_to_cpu(buf[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)
{
int ret;
s64 var1, var2, p;
__le16 buf[BMP280_COMP_PRESS_REG_COUNT / 2];
ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START,
buf, BMP280_COMP_PRESS_REG_COUNT);
if (ret < 0) {
dev_err(data->dev,
"failed to read pressure calibration parameters\n");
return ret;
}
var1 = ((s64)data->t_fine) - 128000;
var2 = var1 * var1 * (s64)(s16)le16_to_cpu(buf[P6]);
var2 += (var1 * (s64)(s16)le16_to_cpu(buf[P5])) << 17;
var2 += ((s64)(s16)le16_to_cpu(buf[P4])) << 35;
var1 = ((var1 * var1 * (s64)(s16)le16_to_cpu(buf[P3])) >> 8) +
((var1 * (s64)(s16)le16_to_cpu(buf[P2])) << 12);
var1 = ((((s64)1) << 47) + var1) * ((s64)le16_to_cpu(buf[P1])) >> 33;
if (var1 == 0)
return 0;
p = ((((s64)1048576 - adc_press) << 31) - var2) * 3125;
p = div64_s64(p, var1);
var1 = (((s64)(s16)le16_to_cpu(buf[P9])) * (p >> 13) * (p >> 13)) >> 25;
var2 = (((s64)(s16)le16_to_cpu(buf[P8])) * p) >> 19;
p = ((p + var1 + var2) >> 8) + (((s64)(s16)le16_to_cpu(buf[P7])) << 4);
return (u32)p;
}
static int bmp280_read_temp(struct bmp280_data *data,
int *val)
{
int ret;
__be32 tmp = 0;
s32 adc_temp, comp_temp;
ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB,
(u8 *) &tmp, 3);
if (ret < 0) {
dev_err(data->dev, "failed to read temperature\n");
return ret;
}
adc_temp = be32_to_cpu(tmp) >> 12;
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)
{
int ret;
__be32 tmp = 0;
s32 adc_press;
u32 comp_press;
/* 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,
(u8 *) &tmp, 3);
if (ret < 0) {
dev_err(data->dev, "failed to read pressure\n");
return ret;
}
adc_press = be32_to_cpu(tmp) >> 12;
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)
{
int ret;
__be16 tmp = 0;
s32 adc_humidity;
u32 comp_humidity;
/* 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,
(u8 *) &tmp, 2);
if (ret < 0) {
dev_err(data->dev, "failed to read humidity\n");
return ret;
}
adc_humidity = be16_to_cpu(tmp);
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;
*val2 = 1024;
return IIO_VAL_FRACTIONAL;
}
static int bmp280_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
int ret;
struct bmp280_data *data = iio_priv(indio_dev);
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;
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)
{
int i;
const int *avail = data->chip_info->oversampling_humid_avail;
const int n = data->chip_info->num_oversampling_humid_avail;
for (i = 0; i < n; i++) {
if (avail[i] == val) {
data->oversampling_humid = ilog2(val);
return data->chip_info->chip_config(data);
}
}
return -EINVAL;
}
static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data,
int val)
{
int i;
const int *avail = data->chip_info->oversampling_temp_avail;
const int n = data->chip_info->num_oversampling_temp_avail;
for (i = 0; i < n; i++) {
if (avail[i] == val) {
data->oversampling_temp = ilog2(val);
return data->chip_info->chip_config(data);
}
}
return -EINVAL;
}
static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data,
int val)
{
int i;
const int *avail = data->chip_info->oversampling_press_avail;
const int n = data->chip_info->num_oversampling_press_avail;
for (i = 0; i < n; i++) {
if (avail[i] == val) {
data->oversampling_press = ilog2(val);
return data->chip_info->chip_config(data);
}
}
return -EINVAL;
}
static int bmp280_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
int ret = 0;
struct bmp280_data *data = iio_priv(indio_dev);
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;
default:
return -EINVAL;
}
return ret;
}
static ssize_t bmp280_show_avail(char *buf, const int *vals, const int n)
{
size_t len = 0;
int i;
for (i = 0; i < n; i++)
len += scnprintf(buf + len, PAGE_SIZE - len, "%d ", vals[i]);
buf[len - 1] = '\n';
return len;
}
static ssize_t bmp280_show_temp_oversampling_avail(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev));
return bmp280_show_avail(buf, data->chip_info->oversampling_temp_avail,
data->chip_info->num_oversampling_temp_avail);
}
static ssize_t bmp280_show_press_oversampling_avail(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct bmp280_data *data = iio_priv(dev_to_iio_dev(dev));
return bmp280_show_avail(buf, data->chip_info->oversampling_press_avail,
data->chip_info->num_oversampling_press_avail);
}
static IIO_DEVICE_ATTR(in_temp_oversampling_ratio_available,
S_IRUGO, bmp280_show_temp_oversampling_avail, NULL, 0);
static IIO_DEVICE_ATTR(in_pressure_oversampling_ratio_available,
S_IRUGO, bmp280_show_press_oversampling_avail, NULL, 0);
static struct attribute *bmp280_attributes[] = {
&iio_dev_attr_in_temp_oversampling_ratio_available.dev_attr.attr,
&iio_dev_attr_in_pressure_oversampling_ratio_available.dev_attr.attr,
NULL,
};
static const struct attribute_group bmp280_attrs_group = {
.attrs = bmp280_attributes,
};
static const struct iio_info bmp280_info = {
.read_raw = &bmp280_read_raw,
.write_raw = &bmp280_write_raw,
.attrs = &bmp280_attrs_group,
};
static int bmp280_chip_config(struct bmp280_data *data)
{
int ret;
u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) |
BMP280_OSRS_PRESS_X(data->oversampling_press + 1);
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 = {
.oversampling_temp_avail = bmp280_oversampling_avail,
.num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
.oversampling_press_avail = bmp280_oversampling_avail,
.num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
.chip_config = bmp280_chip_config,
.read_temp = bmp280_read_temp,
.read_press = bmp280_read_press,
};
static int bme280_chip_config(struct bmp280_data *data)
{
int ret;
u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1);
/*
* 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 = {
.oversampling_temp_avail = bmp280_oversampling_avail,
.num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
.oversampling_press_avail = bmp280_oversampling_avail,
.num_oversampling_press_avail = ARRAY_SIZE(bmp280_oversampling_avail),
.oversampling_humid_avail = bmp280_oversampling_avail,
.num_oversampling_humid_avail = ARRAY_SIZE(bmp280_oversampling_avail),
.chip_config = bme280_chip_config,
.read_temp = bmp280_read_temp,
.read_press = bmp280_read_press,
.read_humid = bmp280_read_humid,
};
static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
{
int ret;
const int conversion_time_max[] = { 4500, 7500, 13500, 25500 };
unsigned int delay_us;
unsigned int ctrl;
if (data->use_eoc)
init_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 (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;
__be16 tmp = 0;
ret = bmp180_measure(data, BMP180_MEAS_TEMP);
if (ret)
return ret;
ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 2);
if (ret)
return ret;
*val = be16_to_cpu(tmp);
return 0;
}
static int bmp180_read_calib(struct bmp280_data *data,
struct bmp180_calib *calib)
{
int ret;
int i;
__be16 buf[BMP180_REG_CALIB_COUNT / 2];
ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf,
sizeof(buf));
if (ret < 0)
return ret;
/* None of the words has the value 0 or 0xFFFF */
for (i = 0; i < ARRAY_SIZE(buf); i++) {
if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(0xffff))
return -EIO;
}
/* Toss the calibration data into the entropy pool */
add_device_randomness(buf, sizeof(buf));
calib->AC1 = be16_to_cpu(buf[AC1]);
calib->AC2 = be16_to_cpu(buf[AC2]);
calib->AC3 = be16_to_cpu(buf[AC3]);
calib->AC4 = be16_to_cpu(buf[AC4]);
calib->AC5 = be16_to_cpu(buf[AC5]);
calib->AC6 = be16_to_cpu(buf[AC6]);
calib->B1 = be16_to_cpu(buf[B1]);
calib->B2 = be16_to_cpu(buf[B2]);
calib->MB = be16_to_cpu(buf[MB]);
calib->MC = be16_to_cpu(buf[MC]);
calib->MD = be16_to_cpu(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)
{
s32 x1, x2;
struct bmp180_calib *calib = &data->calib;
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)
{
int ret;
s32 adc_temp, comp_temp;
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)
{
int ret;
__be32 tmp = 0;
u8 oss = data->oversampling_press;
ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss));
if (ret)
return ret;
ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, (u8 *)&tmp, 3);
if (ret)
return ret;
*val = (be32_to_cpu(tmp) >> 8) >> (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)
{
s32 x1, x2, x3, p;
s32 b3, b6;
u32 b4, b7;
s32 oss = data->oversampling_press;
struct bmp180_calib *calib = &data->calib;
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)
{
int ret;
s32 adc_press;
u32 comp_press;
/* 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 = {
.oversampling_temp_avail = bmp180_oversampling_temp_avail,
.num_oversampling_temp_avail =
ARRAY_SIZE(bmp180_oversampling_temp_avail),
.oversampling_press_avail = bmp180_oversampling_press_avail,
.num_oversampling_press_avail =
ARRAY_SIZE(bmp180_oversampling_press_avail),
.chip_config = bmp180_chip_config,
.read_temp = bmp180_read_temp,
.read_press = bmp180_read_press,
};
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;
}
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;
}
int bmp280_common_probe(struct device *dev,
struct regmap *regmap,
unsigned int chip,
const char *name,
int irq)
{
int ret;
struct iio_dev *indio_dev;
struct bmp280_data *data;
unsigned int chip_id;
struct gpio_desc *gpiod;
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->dev.parent = dev;
indio_dev->name = name;
indio_dev->channels = bmp280_channels;
indio_dev->info = &bmp280_info;
indio_dev->modes = INDIO_DIRECT_MODE;
switch (chip) {
case BMP180_CHIP_ID:
indio_dev->num_channels = 2;
data->chip_info = &bmp180_chip_info;
data->oversampling_press = ilog2(8);
data->oversampling_temp = ilog2(1);
data->start_up_time = 10000;
break;
case BMP280_CHIP_ID:
indio_dev->num_channels = 2;
data->chip_info = &bmp280_chip_info;
data->oversampling_press = ilog2(16);
data->oversampling_temp = ilog2(2);
data->start_up_time = 2000;
break;
case BME280_CHIP_ID:
indio_dev->num_channels = 3;
data->chip_info = &bme280_chip_info;
data->oversampling_press = ilog2(16);
data->oversampling_humid = ilog2(16);
data->oversampling_temp = ilog2(2);
data->start_up_time = 2000;
break;
default:
return -EINVAL;
}
/* Bring up regulators */
data->vddd = devm_regulator_get(dev, "vddd");
if (IS_ERR(data->vddd)) {
dev_err(dev, "failed to get VDDD regulator\n");
return PTR_ERR(data->vddd);
}
ret = regulator_enable(data->vddd);
if (ret) {
dev_err(dev, "failed to enable VDDD regulator\n");
return ret;
}
data->vdda = devm_regulator_get(dev, "vdda");
if (IS_ERR(data->vdda)) {
dev_err(dev, "failed to get VDDA regulator\n");
ret = PTR_ERR(data->vdda);
goto out_disable_vddd;
}
ret = regulator_enable(data->vdda);
if (ret) {
dev_err(dev, "failed to enable VDDA regulator\n");
goto out_disable_vddd;
}
/* 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(dev, "reset", GPIOD_OUT_HIGH);
/* Deassert the signal */
if (!IS_ERR(gpiod)) {
dev_info(dev, "release reset\n");
gpiod_set_value(gpiod, 0);
}
data->regmap = regmap;
ret = regmap_read(regmap, BMP280_REG_ID, &chip_id);
if (ret < 0)
goto out_disable_vdda;
if (chip_id != chip) {
dev_err(dev, "bad chip id: expected %x got %x\n",
chip, chip_id);
ret = -EINVAL;
goto out_disable_vdda;
}
ret = data->chip_info->chip_config(data);
if (ret < 0)
goto out_disable_vdda;
dev_set_drvdata(dev, indio_dev);
/*
* The BMP085 and BMP180 has calibration in an E2PROM, read it out
* at probe time. It will not change.
*/
if (chip_id == BMP180_CHIP_ID) {
ret = bmp180_read_calib(data, &data->calib);
if (ret < 0) {
dev_err(data->dev,
"failed to read calibration coefficients\n");
goto out_disable_vdda;
}
}
/*
* 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)
goto out_disable_vdda;
}
/* 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 = iio_device_register(indio_dev);
if (ret)
goto out_runtime_pm_disable;
return 0;
out_runtime_pm_disable:
pm_runtime_get_sync(data->dev);
pm_runtime_put_noidle(data->dev);
pm_runtime_disable(data->dev);
out_disable_vdda:
regulator_disable(data->vdda);
out_disable_vddd:
regulator_disable(data->vddd);
return ret;
}
EXPORT_SYMBOL(bmp280_common_probe);
int bmp280_common_remove(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct bmp280_data *data = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
pm_runtime_get_sync(data->dev);
pm_runtime_put_noidle(data->dev);
pm_runtime_disable(data->dev);
regulator_disable(data->vdda);
regulator_disable(data->vddd);
return 0;
}
EXPORT_SYMBOL(bmp280_common_remove);
#ifdef CONFIG_PM
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);
int ret;
ret = regulator_disable(data->vdda);
if (ret)
return ret;
return regulator_disable(data->vddd);
}
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_enable(data->vddd);
if (ret)
return ret;
ret = regulator_enable(data->vdda);
if (ret)
return ret;
usleep_range(data->start_up_time, data->start_up_time + 100);
return data->chip_info->chip_config(data);
}
#endif /* CONFIG_PM */
const struct dev_pm_ops bmp280_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
SET_RUNTIME_PM_OPS(bmp280_runtime_suspend,
bmp280_runtime_resume, NULL)
};
EXPORT_SYMBOL(bmp280_dev_pm_ops);
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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