mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
826 lines
18 KiB
826 lines
18 KiB
// SPDX-License-Identifier: GPL-2.0+ |
|
// Copyright IBM Corp 2019 |
|
/* |
|
* The DPS310 is a barometric pressure and temperature sensor. |
|
* Currently only reading a single temperature is supported by |
|
* this driver. |
|
* |
|
* https://www.infineon.com/dgdl/?fileId=5546d462576f34750157750826c42242 |
|
* |
|
* Temperature calculation: |
|
* c0 * 0.5 + c1 * T_raw / kT °C |
|
* |
|
* TODO: |
|
* - Optionally support the FIFO |
|
*/ |
|
|
|
#include <linux/i2c.h> |
|
#include <linux/limits.h> |
|
#include <linux/math64.h> |
|
#include <linux/module.h> |
|
#include <linux/regmap.h> |
|
|
|
#include <linux/iio/iio.h> |
|
#include <linux/iio/sysfs.h> |
|
|
|
#define DPS310_DEV_NAME "dps310" |
|
|
|
#define DPS310_PRS_B0 0x00 |
|
#define DPS310_PRS_B1 0x01 |
|
#define DPS310_PRS_B2 0x02 |
|
#define DPS310_TMP_B0 0x03 |
|
#define DPS310_TMP_B1 0x04 |
|
#define DPS310_TMP_B2 0x05 |
|
#define DPS310_PRS_CFG 0x06 |
|
#define DPS310_PRS_RATE_BITS GENMASK(6, 4) |
|
#define DPS310_PRS_PRC_BITS GENMASK(3, 0) |
|
#define DPS310_TMP_CFG 0x07 |
|
#define DPS310_TMP_RATE_BITS GENMASK(6, 4) |
|
#define DPS310_TMP_PRC_BITS GENMASK(3, 0) |
|
#define DPS310_TMP_EXT BIT(7) |
|
#define DPS310_MEAS_CFG 0x08 |
|
#define DPS310_MEAS_CTRL_BITS GENMASK(2, 0) |
|
#define DPS310_PRS_EN BIT(0) |
|
#define DPS310_TEMP_EN BIT(1) |
|
#define DPS310_BACKGROUND BIT(2) |
|
#define DPS310_PRS_RDY BIT(4) |
|
#define DPS310_TMP_RDY BIT(5) |
|
#define DPS310_SENSOR_RDY BIT(6) |
|
#define DPS310_COEF_RDY BIT(7) |
|
#define DPS310_CFG_REG 0x09 |
|
#define DPS310_INT_HL BIT(7) |
|
#define DPS310_TMP_SHIFT_EN BIT(3) |
|
#define DPS310_PRS_SHIFT_EN BIT(4) |
|
#define DPS310_FIFO_EN BIT(5) |
|
#define DPS310_SPI_EN BIT(6) |
|
#define DPS310_RESET 0x0c |
|
#define DPS310_RESET_MAGIC 0x09 |
|
#define DPS310_COEF_BASE 0x10 |
|
|
|
/* Make sure sleep time is <= 20ms for usleep_range */ |
|
#define DPS310_POLL_SLEEP_US(t) min(20000, (t) / 8) |
|
/* Silently handle error in rate value here */ |
|
#define DPS310_POLL_TIMEOUT_US(rc) ((rc) <= 0 ? 1000000 : 1000000 / (rc)) |
|
|
|
#define DPS310_PRS_BASE DPS310_PRS_B0 |
|
#define DPS310_TMP_BASE DPS310_TMP_B0 |
|
|
|
/* |
|
* These values (defined in the spec) indicate how to scale the raw register |
|
* values for each level of precision available. |
|
*/ |
|
static const int scale_factors[] = { |
|
524288, |
|
1572864, |
|
3670016, |
|
7864320, |
|
253952, |
|
516096, |
|
1040384, |
|
2088960, |
|
}; |
|
|
|
struct dps310_data { |
|
struct i2c_client *client; |
|
struct regmap *regmap; |
|
struct mutex lock; /* Lock for sequential HW access functions */ |
|
|
|
s32 c0, c1; |
|
s32 c00, c10, c20, c30, c01, c11, c21; |
|
s32 pressure_raw; |
|
s32 temp_raw; |
|
}; |
|
|
|
static const struct iio_chan_spec dps310_channels[] = { |
|
{ |
|
.type = IIO_TEMP, |
|
.info_mask_separate = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | |
|
BIT(IIO_CHAN_INFO_SAMP_FREQ) | |
|
BIT(IIO_CHAN_INFO_PROCESSED), |
|
}, |
|
{ |
|
.type = IIO_PRESSURE, |
|
.info_mask_separate = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | |
|
BIT(IIO_CHAN_INFO_SAMP_FREQ) | |
|
BIT(IIO_CHAN_INFO_PROCESSED), |
|
}, |
|
}; |
|
|
|
/* To be called after checking the COEF_RDY bit in MEAS_CFG */ |
|
static int dps310_get_coefs(struct dps310_data *data) |
|
{ |
|
int rc; |
|
u8 coef[18]; |
|
u32 c0, c1; |
|
u32 c00, c10, c20, c30, c01, c11, c21; |
|
|
|
/* Read all sensor calibration coefficients from the COEF registers. */ |
|
rc = regmap_bulk_read(data->regmap, DPS310_COEF_BASE, coef, |
|
sizeof(coef)); |
|
if (rc < 0) |
|
return rc; |
|
|
|
/* |
|
* Calculate temperature calibration coefficients c0 and c1. The |
|
* numbers are 12-bit 2's complement numbers. |
|
*/ |
|
c0 = (coef[0] << 4) | (coef[1] >> 4); |
|
data->c0 = sign_extend32(c0, 11); |
|
|
|
c1 = ((coef[1] & GENMASK(3, 0)) << 8) | coef[2]; |
|
data->c1 = sign_extend32(c1, 11); |
|
|
|
/* |
|
* Calculate pressure calibration coefficients. c00 and c10 are 20 bit |
|
* 2's complement numbers, while the rest are 16 bit 2's complement |
|
* numbers. |
|
*/ |
|
c00 = (coef[3] << 12) | (coef[4] << 4) | (coef[5] >> 4); |
|
data->c00 = sign_extend32(c00, 19); |
|
|
|
c10 = ((coef[5] & GENMASK(3, 0)) << 16) | (coef[6] << 8) | coef[7]; |
|
data->c10 = sign_extend32(c10, 19); |
|
|
|
c01 = (coef[8] << 8) | coef[9]; |
|
data->c01 = sign_extend32(c01, 15); |
|
|
|
c11 = (coef[10] << 8) | coef[11]; |
|
data->c11 = sign_extend32(c11, 15); |
|
|
|
c20 = (coef[12] << 8) | coef[13]; |
|
data->c20 = sign_extend32(c20, 15); |
|
|
|
c21 = (coef[14] << 8) | coef[15]; |
|
data->c21 = sign_extend32(c21, 15); |
|
|
|
c30 = (coef[16] << 8) | coef[17]; |
|
data->c30 = sign_extend32(c30, 15); |
|
|
|
return 0; |
|
} |
|
|
|
static int dps310_get_pres_precision(struct dps310_data *data) |
|
{ |
|
int rc; |
|
int val; |
|
|
|
rc = regmap_read(data->regmap, DPS310_PRS_CFG, &val); |
|
if (rc < 0) |
|
return rc; |
|
|
|
return BIT(val & GENMASK(2, 0)); |
|
} |
|
|
|
static int dps310_get_temp_precision(struct dps310_data *data) |
|
{ |
|
int rc; |
|
int val; |
|
|
|
rc = regmap_read(data->regmap, DPS310_TMP_CFG, &val); |
|
if (rc < 0) |
|
return rc; |
|
|
|
/* |
|
* Scale factor is bottom 4 bits of the register, but 1111 is |
|
* reserved so just grab bottom three |
|
*/ |
|
return BIT(val & GENMASK(2, 0)); |
|
} |
|
|
|
/* Called with lock held */ |
|
static int dps310_set_pres_precision(struct dps310_data *data, int val) |
|
{ |
|
int rc; |
|
u8 shift_en; |
|
|
|
if (val < 0 || val > 128) |
|
return -EINVAL; |
|
|
|
shift_en = val >= 16 ? DPS310_PRS_SHIFT_EN : 0; |
|
rc = regmap_write_bits(data->regmap, DPS310_CFG_REG, |
|
DPS310_PRS_SHIFT_EN, shift_en); |
|
if (rc) |
|
return rc; |
|
|
|
return regmap_update_bits(data->regmap, DPS310_PRS_CFG, |
|
DPS310_PRS_PRC_BITS, ilog2(val)); |
|
} |
|
|
|
/* Called with lock held */ |
|
static int dps310_set_temp_precision(struct dps310_data *data, int val) |
|
{ |
|
int rc; |
|
u8 shift_en; |
|
|
|
if (val < 0 || val > 128) |
|
return -EINVAL; |
|
|
|
shift_en = val >= 16 ? DPS310_TMP_SHIFT_EN : 0; |
|
rc = regmap_write_bits(data->regmap, DPS310_CFG_REG, |
|
DPS310_TMP_SHIFT_EN, shift_en); |
|
if (rc) |
|
return rc; |
|
|
|
return regmap_update_bits(data->regmap, DPS310_TMP_CFG, |
|
DPS310_TMP_PRC_BITS, ilog2(val)); |
|
} |
|
|
|
/* Called with lock held */ |
|
static int dps310_set_pres_samp_freq(struct dps310_data *data, int freq) |
|
{ |
|
u8 val; |
|
|
|
if (freq < 0 || freq > 128) |
|
return -EINVAL; |
|
|
|
val = ilog2(freq) << 4; |
|
|
|
return regmap_update_bits(data->regmap, DPS310_PRS_CFG, |
|
DPS310_PRS_RATE_BITS, val); |
|
} |
|
|
|
/* Called with lock held */ |
|
static int dps310_set_temp_samp_freq(struct dps310_data *data, int freq) |
|
{ |
|
u8 val; |
|
|
|
if (freq < 0 || freq > 128) |
|
return -EINVAL; |
|
|
|
val = ilog2(freq) << 4; |
|
|
|
return regmap_update_bits(data->regmap, DPS310_TMP_CFG, |
|
DPS310_TMP_RATE_BITS, val); |
|
} |
|
|
|
static int dps310_get_pres_samp_freq(struct dps310_data *data) |
|
{ |
|
int rc; |
|
int val; |
|
|
|
rc = regmap_read(data->regmap, DPS310_PRS_CFG, &val); |
|
if (rc < 0) |
|
return rc; |
|
|
|
return BIT((val & DPS310_PRS_RATE_BITS) >> 4); |
|
} |
|
|
|
static int dps310_get_temp_samp_freq(struct dps310_data *data) |
|
{ |
|
int rc; |
|
int val; |
|
|
|
rc = regmap_read(data->regmap, DPS310_TMP_CFG, &val); |
|
if (rc < 0) |
|
return rc; |
|
|
|
return BIT((val & DPS310_TMP_RATE_BITS) >> 4); |
|
} |
|
|
|
static int dps310_get_pres_k(struct dps310_data *data) |
|
{ |
|
int rc = dps310_get_pres_precision(data); |
|
|
|
if (rc < 0) |
|
return rc; |
|
|
|
return scale_factors[ilog2(rc)]; |
|
} |
|
|
|
static int dps310_get_temp_k(struct dps310_data *data) |
|
{ |
|
int rc = dps310_get_temp_precision(data); |
|
|
|
if (rc < 0) |
|
return rc; |
|
|
|
return scale_factors[ilog2(rc)]; |
|
} |
|
|
|
static int dps310_read_pres_raw(struct dps310_data *data) |
|
{ |
|
int rc; |
|
int rate; |
|
int ready; |
|
int timeout; |
|
s32 raw; |
|
u8 val[3]; |
|
|
|
if (mutex_lock_interruptible(&data->lock)) |
|
return -EINTR; |
|
|
|
rate = dps310_get_pres_samp_freq(data); |
|
timeout = DPS310_POLL_TIMEOUT_US(rate); |
|
|
|
/* Poll for sensor readiness; base the timeout upon the sample rate. */ |
|
rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, |
|
ready & DPS310_PRS_RDY, |
|
DPS310_POLL_SLEEP_US(timeout), timeout); |
|
if (rc) |
|
goto done; |
|
|
|
rc = regmap_bulk_read(data->regmap, DPS310_PRS_BASE, val, sizeof(val)); |
|
if (rc < 0) |
|
goto done; |
|
|
|
raw = (val[0] << 16) | (val[1] << 8) | val[2]; |
|
data->pressure_raw = sign_extend32(raw, 23); |
|
|
|
done: |
|
mutex_unlock(&data->lock); |
|
return rc; |
|
} |
|
|
|
/* Called with lock held */ |
|
static int dps310_read_temp_ready(struct dps310_data *data) |
|
{ |
|
int rc; |
|
u8 val[3]; |
|
s32 raw; |
|
|
|
rc = regmap_bulk_read(data->regmap, DPS310_TMP_BASE, val, sizeof(val)); |
|
if (rc < 0) |
|
return rc; |
|
|
|
raw = (val[0] << 16) | (val[1] << 8) | val[2]; |
|
data->temp_raw = sign_extend32(raw, 23); |
|
|
|
return 0; |
|
} |
|
|
|
static int dps310_read_temp_raw(struct dps310_data *data) |
|
{ |
|
int rc; |
|
int rate; |
|
int ready; |
|
int timeout; |
|
|
|
if (mutex_lock_interruptible(&data->lock)) |
|
return -EINTR; |
|
|
|
rate = dps310_get_temp_samp_freq(data); |
|
timeout = DPS310_POLL_TIMEOUT_US(rate); |
|
|
|
/* Poll for sensor readiness; base the timeout upon the sample rate. */ |
|
rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, |
|
ready & DPS310_TMP_RDY, |
|
DPS310_POLL_SLEEP_US(timeout), timeout); |
|
if (rc < 0) |
|
goto done; |
|
|
|
rc = dps310_read_temp_ready(data); |
|
|
|
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; |
|
|
|
regmap_write(data->regmap, DPS310_RESET, DPS310_RESET_MAGIC); |
|
} |
|
|
|
static const struct regmap_config dps310_regmap_config = { |
|
.reg_bits = 8, |
|
.val_bits = 8, |
|
.writeable_reg = dps310_is_writeable_reg, |
|
.volatile_reg = dps310_is_volatile_reg, |
|
.cache_type = REGCACHE_RBTREE, |
|
.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, |
|
}; |
|
|
|
/* |
|
* Some verions of chip will read temperatures in the ~60C range when |
|
* its actually ~20C. This is the manufacturer recommended workaround |
|
* to correct the issue. The registers used below are undocumented. |
|
*/ |
|
static int dps310_temp_workaround(struct dps310_data *data) |
|
{ |
|
int rc; |
|
int reg; |
|
|
|
rc = regmap_read(data->regmap, 0x32, ®); |
|
if (rc < 0) |
|
return rc; |
|
|
|
/* |
|
* If bit 1 is set then the device is okay, and the workaround does not |
|
* need to be applied |
|
*/ |
|
if (reg & BIT(1)) |
|
return 0; |
|
|
|
rc = regmap_write(data->regmap, 0x0e, 0xA5); |
|
if (rc < 0) |
|
return rc; |
|
|
|
rc = regmap_write(data->regmap, 0x0f, 0x96); |
|
if (rc < 0) |
|
return rc; |
|
|
|
rc = regmap_write(data->regmap, 0x62, 0x02); |
|
if (rc < 0) |
|
return rc; |
|
|
|
rc = regmap_write(data->regmap, 0x0e, 0x00); |
|
if (rc < 0) |
|
return rc; |
|
|
|
return regmap_write(data->regmap, 0x0f, 0x00); |
|
} |
|
|
|
static int dps310_probe(struct i2c_client *client, |
|
const struct i2c_device_id *id) |
|
{ |
|
struct dps310_data *data; |
|
struct iio_dev *iio; |
|
int rc, ready; |
|
|
|
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; |
|
|
|
/* |
|
* Set up pressure sensor in single sample, one measurement per second |
|
* mode |
|
*/ |
|
rc = regmap_write(data->regmap, DPS310_PRS_CFG, 0); |
|
|
|
/* |
|
* Set up external (MEMS) temperature sensor in single sample, one |
|
* measurement per second mode |
|
*/ |
|
rc = regmap_write(data->regmap, DPS310_TMP_CFG, DPS310_TMP_EXT); |
|
if (rc < 0) |
|
return rc; |
|
|
|
/* Temp and pressure shifts are disabled when PRC <= 8 */ |
|
rc = regmap_write_bits(data->regmap, DPS310_CFG_REG, |
|
DPS310_PRS_SHIFT_EN | DPS310_TMP_SHIFT_EN, 0); |
|
if (rc < 0) |
|
return rc; |
|
|
|
/* MEAS_CFG doesn't update correctly unless first written with 0 */ |
|
rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG, |
|
DPS310_MEAS_CTRL_BITS, 0); |
|
if (rc < 0) |
|
return rc; |
|
|
|
/* Turn on temperature and pressure measurement in the background */ |
|
rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG, |
|
DPS310_MEAS_CTRL_BITS, DPS310_PRS_EN | |
|
DPS310_TEMP_EN | DPS310_BACKGROUND); |
|
if (rc < 0) |
|
return rc; |
|
|
|
/* |
|
* Calibration coefficients required for reporting temperature. |
|
* They are available 40ms after the device has started |
|
*/ |
|
rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, |
|
ready & DPS310_COEF_RDY, 10000, 40000); |
|
if (rc < 0) |
|
return rc; |
|
|
|
rc = dps310_get_coefs(data); |
|
if (rc < 0) |
|
return rc; |
|
|
|
rc = dps310_temp_workaround(data); |
|
if (rc < 0) |
|
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 struct i2c_driver dps310_driver = { |
|
.driver = { |
|
.name = DPS310_DEV_NAME, |
|
}, |
|
.probe = dps310_probe, |
|
.id_table = dps310_id, |
|
}; |
|
module_i2c_driver(dps310_driver); |
|
|
|
MODULE_AUTHOR("Joel Stanley <[email protected]>"); |
|
MODULE_DESCRIPTION("Infineon DPS310 pressure and temperature sensor"); |
|
MODULE_LICENSE("GPL v2");
|
|
|