| // 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 <= 30ms for usleep_range */ |
| #define DPS310_POLL_SLEEP_US(t) min(30000, (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; |
| bool timeout_recovery_failed; |
| }; |
| |
| 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; |
| } |
| |
| /* |
| * Some versions of the chip will read temperatures in the ~60C range when |
| * it's 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) |
| return rc; |
| |
| rc = regmap_write(data->regmap, 0x0f, 0x96); |
| if (rc) |
| return rc; |
| |
| rc = regmap_write(data->regmap, 0x62, 0x02); |
| if (rc) |
| return rc; |
| |
| rc = regmap_write(data->regmap, 0x0e, 0x00); |
| if (rc) |
| return rc; |
| |
| return regmap_write(data->regmap, 0x0f, 0x00); |
| } |
| |
| static int dps310_startup(struct dps310_data *data) |
| { |
| int rc; |
| int ready; |
| |
| /* |
| * Set up pressure sensor in single sample, one measurement per second |
| * mode |
| */ |
| rc = regmap_write(data->regmap, DPS310_PRS_CFG, 0); |
| if (rc) |
| return rc; |
| |
| /* |
| * 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) |
| 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) |
| 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) |
| 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) |
| 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) |
| return rc; |
| |
| rc = dps310_get_coefs(data); |
| if (rc) |
| return rc; |
| |
| return dps310_temp_workaround(data); |
| } |
| |
| static int dps310_get_pres_precision(struct dps310_data *data, int *val) |
| { |
| int reg_val, rc; |
| |
| rc = regmap_read(data->regmap, DPS310_PRS_CFG, ®_val); |
| if (rc < 0) |
| return rc; |
| |
| *val = BIT(reg_val & GENMASK(2, 0)); |
| |
| return 0; |
| } |
| |
| static int dps310_get_temp_precision(struct dps310_data *data, int *val) |
| { |
| int reg_val, rc; |
| |
| 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 |
| */ |
| *val = BIT(reg_val & GENMASK(2, 0)); |
| |
| return 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 *val) |
| { |
| int reg_val, rc; |
| |
| rc = regmap_read(data->regmap, DPS310_PRS_CFG, ®_val); |
| if (rc < 0) |
| return rc; |
| |
| *val = BIT((reg_val & DPS310_PRS_RATE_BITS) >> 4); |
| |
| return 0; |
| } |
| |
| static int dps310_get_temp_samp_freq(struct dps310_data *data, int *val) |
| { |
| int reg_val, rc; |
| |
| rc = regmap_read(data->regmap, DPS310_TMP_CFG, ®_val); |
| if (rc < 0) |
| return rc; |
| |
| *val = BIT((reg_val & DPS310_TMP_RATE_BITS) >> 4); |
| |
| return 0; |
| } |
| |
| static int dps310_get_pres_k(struct dps310_data *data, int *val) |
| { |
| int reg_val, rc; |
| |
| rc = regmap_read(data->regmap, DPS310_PRS_CFG, ®_val); |
| if (rc < 0) |
| return rc; |
| |
| *val = scale_factors[reg_val & GENMASK(2, 0)]; |
| |
| return 0; |
| } |
| |
| static int dps310_get_temp_k(struct dps310_data *data, int *val) |
| { |
| int reg_val, rc; |
| |
| rc = regmap_read(data->regmap, DPS310_TMP_CFG, ®_val); |
| if (rc < 0) |
| return rc; |
| |
| *val = scale_factors[reg_val & GENMASK(2, 0)]; |
| |
| return 0; |
| } |
| |
| static int dps310_reset_wait(struct dps310_data *data) |
| { |
| int rc; |
| |
| rc = regmap_write(data->regmap, DPS310_RESET, DPS310_RESET_MAGIC); |
| if (rc) |
| return rc; |
| |
| /* Wait for device chip access: 15ms in specification */ |
| usleep_range(15000, 55000); |
| return 0; |
| } |
| |
| static int dps310_reset_reinit(struct dps310_data *data) |
| { |
| int rc; |
| |
| rc = dps310_reset_wait(data); |
| if (rc) |
| return rc; |
| |
| return dps310_startup(data); |
| } |
| |
| static int dps310_ready_status(struct dps310_data *data, int ready_bit, int timeout) |
| { |
| int sleep = DPS310_POLL_SLEEP_US(timeout); |
| int ready; |
| |
| return regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, ready & ready_bit, |
| sleep, timeout); |
| } |
| |
| static int dps310_ready(struct dps310_data *data, int ready_bit, int timeout) |
| { |
| int rc; |
| |
| rc = dps310_ready_status(data, ready_bit, timeout); |
| if (rc) { |
| if (rc == -ETIMEDOUT && !data->timeout_recovery_failed) { |
| /* Reset and reinitialize the chip. */ |
| if (dps310_reset_reinit(data)) { |
| data->timeout_recovery_failed = true; |
| } else { |
| /* Try again to get sensor ready status. */ |
| if (dps310_ready_status(data, ready_bit, timeout)) |
| data->timeout_recovery_failed = true; |
| else |
| return 0; |
| } |
| } |
| |
| return rc; |
| } |
| |
| data->timeout_recovery_failed = false; |
| return 0; |
| } |
| |
| static int dps310_read_pres_raw(struct dps310_data *data) |
| { |
| int rc; |
| int rate; |
| int timeout; |
| s32 raw; |
| u8 val[3]; |
| |
| if (mutex_lock_interruptible(&data->lock)) |
| return -EINTR; |
| |
| rc = dps310_get_pres_samp_freq(data, &rate); |
| if (rc) |
| goto done; |
| |
| timeout = DPS310_POLL_TIMEOUT_US(rate); |
| |
| /* Poll for sensor readiness; base the timeout upon the sample rate. */ |
| rc = dps310_ready(data, DPS310_PRS_RDY, 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 timeout; |
| |
| if (mutex_lock_interruptible(&data->lock)) |
| return -EINTR; |
| |
| rc = dps310_get_temp_samp_freq(data, &rate); |
| if (rc) |
| goto done; |
| |
| timeout = DPS310_POLL_TIMEOUT_US(rate); |
| |
| /* Poll for sensor readiness; base the timeout upon the sample rate. */ |
| rc = dps310_ready(data, DPS310_TMP_RDY, timeout); |
| if (rc) |
| goto done; |
| |
| rc = dps310_read_temp_ready(data); |
| |
| done: |
| mutex_unlock(&data->lock); |
| return rc; |
| } |
| |
| static bool dps310_is_writeable_reg(struct device *dev, unsigned int reg) |
| { |
| switch (reg) { |
| case DPS310_PRS_CFG: |
| case DPS310_TMP_CFG: |
| case DPS310_MEAS_CFG: |
| case DPS310_CFG_REG: |
| case DPS310_RESET: |
| /* No documentation available on the registers below */ |
| case 0x0e: |
| case 0x0f: |
| case 0x62: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| static bool dps310_is_volatile_reg(struct device *dev, unsigned int reg) |
| { |
| switch (reg) { |
| case DPS310_PRS_B0: |
| case DPS310_PRS_B1: |
| case DPS310_PRS_B2: |
| case DPS310_TMP_B0: |
| case DPS310_TMP_B1: |
| case DPS310_TMP_B2: |
| case DPS310_MEAS_CFG: |
| case 0x32: /* No documentation available on this register */ |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| static int dps310_write_raw(struct iio_dev *iio, |
| struct iio_chan_spec const *chan, int val, |
| int val2, long mask) |
| { |
| int rc; |
| struct dps310_data *data = iio_priv(iio); |
| |
| if (mutex_lock_interruptible(&data->lock)) |
| return -EINTR; |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_SAMP_FREQ: |
| switch (chan->type) { |
| case IIO_PRESSURE: |
| rc = dps310_set_pres_samp_freq(data, val); |
| break; |
| |
| case IIO_TEMP: |
| rc = dps310_set_temp_samp_freq(data, val); |
| break; |
| |
| default: |
| rc = -EINVAL; |
| break; |
| } |
| break; |
| |
| case IIO_CHAN_INFO_OVERSAMPLING_RATIO: |
| switch (chan->type) { |
| case IIO_PRESSURE: |
| rc = dps310_set_pres_precision(data, val); |
| break; |
| |
| case IIO_TEMP: |
| rc = dps310_set_temp_precision(data, val); |
| break; |
| |
| default: |
| rc = -EINVAL; |
| break; |
| } |
| break; |
| |
| default: |
| rc = -EINVAL; |
| break; |
| } |
| |
| mutex_unlock(&data->lock); |
| return rc; |
| } |
| |
| static int dps310_calculate_pressure(struct dps310_data *data, int *val) |
| { |
| int i; |
| int rc; |
| int t_ready; |
| int kpi; |
| int kti; |
| s64 rem = 0ULL; |
| s64 pressure = 0ULL; |
| s64 p; |
| s64 t; |
| s64 denoms[7]; |
| s64 nums[7]; |
| s64 rems[7]; |
| s64 kp; |
| s64 kt; |
| |
| rc = dps310_get_pres_k(data, &kpi); |
| if (rc) |
| return rc; |
| |
| rc = dps310_get_temp_k(data, &kti); |
| if (rc) |
| return rc; |
| |
| 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; |
| |
| *val = (int)min_t(s64, pressure, INT_MAX); |
| |
| return 0; |
| } |
| |
| 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, val); |
| if (rc) |
| return 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, val); |
| if (rc) |
| return 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, val); |
| if (rc) |
| return rc; |
| return IIO_VAL_INT; |
| |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static int dps310_calculate_temp(struct dps310_data *data, int *val) |
| { |
| s64 c0; |
| s64 t; |
| int kt, rc; |
| |
| rc = dps310_get_temp_k(data, &kt); |
| if (rc) |
| return rc; |
| |
| /* 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 */ |
| *val = (int)div_s64(t * 1000LL, kt); |
| |
| return 0; |
| } |
| |
| 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, val); |
| if (rc) |
| return 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, val); |
| if (rc) |
| return rc; |
| |
| return IIO_VAL_INT; |
| |
| case IIO_CHAN_INFO_OVERSAMPLING_RATIO: |
| rc = dps310_get_temp_precision(data, val); |
| if (rc) |
| return rc; |
| |
| return IIO_VAL_INT; |
| |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static int dps310_read_raw(struct iio_dev *iio, |
| struct iio_chan_spec const *chan, |
| int *val, int *val2, long mask) |
| { |
| struct dps310_data *data = iio_priv(iio); |
| |
| switch (chan->type) { |
| case IIO_PRESSURE: |
| return dps310_read_pressure(data, val, val2, mask); |
| |
| case IIO_TEMP: |
| return dps310_read_temp(data, val, val2, mask); |
| |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static void dps310_reset(void *action_data) |
| { |
| struct dps310_data *data = action_data; |
| |
| dps310_reset_wait(data); |
| } |
| |
| static const struct regmap_config dps310_regmap_config = { |
| .reg_bits = 8, |
| .val_bits = 8, |
| .writeable_reg = dps310_is_writeable_reg, |
| .volatile_reg = dps310_is_volatile_reg, |
| .cache_type = REGCACHE_RBTREE, |
| .max_register = 0x62, /* No documentation available on this register */ |
| }; |
| |
| static const struct iio_info dps310_info = { |
| .read_raw = dps310_read_raw, |
| .write_raw = dps310_write_raw, |
| }; |
| |
| static int dps310_probe(struct i2c_client *client) |
| { |
| const struct i2c_device_id *id = i2c_client_get_device_id(client); |
| struct dps310_data *data; |
| struct iio_dev *iio; |
| int rc; |
| |
| iio = devm_iio_device_alloc(&client->dev, sizeof(*data)); |
| if (!iio) |
| return -ENOMEM; |
| |
| data = iio_priv(iio); |
| data->client = client; |
| mutex_init(&data->lock); |
| |
| iio->name = id->name; |
| iio->channels = dps310_channels; |
| iio->num_channels = ARRAY_SIZE(dps310_channels); |
| iio->info = &dps310_info; |
| iio->modes = INDIO_DIRECT_MODE; |
| |
| data->regmap = devm_regmap_init_i2c(client, &dps310_regmap_config); |
| if (IS_ERR(data->regmap)) |
| return PTR_ERR(data->regmap); |
| |
| /* Register to run the device reset when the device is removed */ |
| rc = devm_add_action_or_reset(&client->dev, dps310_reset, data); |
| if (rc) |
| return rc; |
| |
| rc = dps310_startup(data); |
| if (rc) |
| return rc; |
| |
| rc = devm_iio_device_register(&client->dev, iio); |
| if (rc) |
| return rc; |
| |
| i2c_set_clientdata(client, iio); |
| |
| return 0; |
| } |
| |
| static const struct i2c_device_id dps310_id[] = { |
| { DPS310_DEV_NAME }, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(i2c, dps310_id); |
| |
| static const struct acpi_device_id dps310_acpi_match[] = { |
| { "IFX3100" }, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(acpi, dps310_acpi_match); |
| |
| static struct i2c_driver dps310_driver = { |
| .driver = { |
| .name = DPS310_DEV_NAME, |
| .acpi_match_table = dps310_acpi_match, |
| }, |
| .probe = dps310_probe, |
| .id_table = dps310_id, |
| }; |
| module_i2c_driver(dps310_driver); |
| |
| MODULE_AUTHOR("Joel Stanley <joel@jms.id.au>"); |
| MODULE_DESCRIPTION("Infineon DPS310 pressure and temperature sensor"); |
| MODULE_LICENSE("GPL v2"); |