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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/iio/pressure/dps310.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/iio/pressure/dps310.c')
-rw-r--r--drivers/iio/pressure/dps310.c897
1 files changed, 897 insertions, 0 deletions
diff --git a/drivers/iio/pressure/dps310.c b/drivers/iio/pressure/dps310.c
new file mode 100644
index 000000000..db1b1e482
--- /dev/null
+++ b/drivers/iio/pressure/dps310.c
@@ -0,0 +1,897 @@
+// 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, &reg);
+ if (rc)
+ 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 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_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;
+
+ 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 = 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;
+
+ rate = dps310_get_temp_samp_freq(data);
+ timeout = DPS310_POLL_TIMEOUT_US(rate);
+
+ /* Poll for sensor readiness; base the timeout upon the sample rate. */
+ rc = dps310_ready(data, DPS310_TMP_RDY, timeout);
+ if (rc)
+ goto done;
+
+ rc = dps310_read_temp_ready(data);
+
+done:
+ mutex_unlock(&data->lock);
+ return rc;
+}
+
+static bool dps310_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case DPS310_PRS_CFG:
+ case DPS310_TMP_CFG:
+ case DPS310_MEAS_CFG:
+ case DPS310_CFG_REG:
+ case DPS310_RESET:
+ /* No documentation available on the registers below */
+ case 0x0e:
+ case 0x0f:
+ case 0x62:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static bool dps310_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case DPS310_PRS_B0:
+ case DPS310_PRS_B1:
+ case DPS310_PRS_B2:
+ case DPS310_TMP_B0:
+ case DPS310_TMP_B1:
+ case DPS310_TMP_B2:
+ case DPS310_MEAS_CFG:
+ case 0x32: /* No documentation available on this register */
+ return true;
+ default:
+ return false;
+ }
+}
+
+static int dps310_write_raw(struct iio_dev *iio,
+ struct iio_chan_spec const *chan, int val,
+ int val2, long mask)
+{
+ int rc;
+ struct dps310_data *data = iio_priv(iio);
+
+ if (mutex_lock_interruptible(&data->lock))
+ return -EINTR;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ switch (chan->type) {
+ case IIO_PRESSURE:
+ rc = dps310_set_pres_samp_freq(data, val);
+ break;
+
+ case IIO_TEMP:
+ rc = dps310_set_temp_samp_freq(data, val);
+ break;
+
+ default:
+ rc = -EINVAL;
+ break;
+ }
+ break;
+
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ switch (chan->type) {
+ case IIO_PRESSURE:
+ rc = dps310_set_pres_precision(data, val);
+ break;
+
+ case IIO_TEMP:
+ rc = dps310_set_temp_precision(data, val);
+ break;
+
+ default:
+ rc = -EINVAL;
+ break;
+ }
+ break;
+
+ default:
+ rc = -EINVAL;
+ break;
+ }
+
+ mutex_unlock(&data->lock);
+ return rc;
+}
+
+static int dps310_calculate_pressure(struct dps310_data *data)
+{
+ int i;
+ int rc;
+ int t_ready;
+ int kpi = dps310_get_pres_k(data);
+ int kti = dps310_get_temp_k(data);
+ s64 rem = 0ULL;
+ s64 pressure = 0ULL;
+ s64 p;
+ s64 t;
+ s64 denoms[7];
+ s64 nums[7];
+ s64 rems[7];
+ s64 kp;
+ s64 kt;
+
+ if (kpi < 0)
+ return kpi;
+
+ if (kti < 0)
+ return kti;
+
+ kp = (s64)kpi;
+ kt = (s64)kti;
+
+ /* Refresh temp if it's ready, otherwise just use the latest value */
+ if (mutex_trylock(&data->lock)) {
+ rc = regmap_read(data->regmap, DPS310_MEAS_CFG, &t_ready);
+ if (rc >= 0 && t_ready & DPS310_TMP_RDY)
+ dps310_read_temp_ready(data);
+
+ mutex_unlock(&data->lock);
+ }
+
+ p = (s64)data->pressure_raw;
+ t = (s64)data->temp_raw;
+
+ /* Section 4.9.1 of the DPS310 spec; algebra'd to avoid underflow */
+ nums[0] = (s64)data->c00;
+ denoms[0] = 1LL;
+ nums[1] = p * (s64)data->c10;
+ denoms[1] = kp;
+ nums[2] = p * p * (s64)data->c20;
+ denoms[2] = kp * kp;
+ nums[3] = p * p * p * (s64)data->c30;
+ denoms[3] = kp * kp * kp;
+ nums[4] = t * (s64)data->c01;
+ denoms[4] = kt;
+ nums[5] = t * p * (s64)data->c11;
+ denoms[5] = kp * kt;
+ nums[6] = t * p * p * (s64)data->c21;
+ denoms[6] = kp * kp * kt;
+
+ /* Kernel lacks a div64_s64_rem function; denoms are all positive */
+ for (i = 0; i < 7; ++i) {
+ u64 irem;
+
+ if (nums[i] < 0LL) {
+ pressure -= div64_u64_rem(-nums[i], denoms[i], &irem);
+ rems[i] = -irem;
+ } else {
+ pressure += div64_u64_rem(nums[i], denoms[i], &irem);
+ rems[i] = (s64)irem;
+ }
+ }
+
+ /* Increase precision and calculate the remainder sum */
+ for (i = 0; i < 7; ++i)
+ rem += div64_s64((s64)rems[i] * 1000000000LL, denoms[i]);
+
+ pressure += div_s64(rem, 1000000000LL);
+ if (pressure < 0LL)
+ return -ERANGE;
+
+ return (int)min_t(s64, pressure, INT_MAX);
+}
+
+static int dps310_read_pressure(struct dps310_data *data, int *val, int *val2,
+ long mask)
+{
+ int rc;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ rc = dps310_get_pres_samp_freq(data);
+ if (rc < 0)
+ return rc;
+
+ *val = rc;
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_PROCESSED:
+ rc = dps310_read_pres_raw(data);
+ if (rc)
+ return rc;
+
+ rc = dps310_calculate_pressure(data);
+ if (rc < 0)
+ return rc;
+
+ *val = rc;
+ *val2 = 1000; /* Convert Pa to KPa per IIO ABI */
+ return IIO_VAL_FRACTIONAL;
+
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ rc = dps310_get_pres_precision(data);
+ if (rc < 0)
+ return rc;
+
+ *val = rc;
+ return IIO_VAL_INT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int dps310_calculate_temp(struct dps310_data *data)
+{
+ s64 c0;
+ s64 t;
+ int kt = dps310_get_temp_k(data);
+
+ if (kt < 0)
+ return kt;
+
+ /* Obtain inverse-scaled offset */
+ c0 = div_s64((s64)kt * (s64)data->c0, 2);
+
+ /* Add the offset to the unscaled temperature */
+ t = c0 + ((s64)data->temp_raw * (s64)data->c1);
+
+ /* Convert to milliCelsius and scale the temperature */
+ return (int)div_s64(t * 1000LL, kt);
+}
+
+static int dps310_read_temp(struct dps310_data *data, int *val, int *val2,
+ long mask)
+{
+ int rc;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ rc = dps310_get_temp_samp_freq(data);
+ if (rc < 0)
+ return rc;
+
+ *val = rc;
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_PROCESSED:
+ rc = dps310_read_temp_raw(data);
+ if (rc)
+ return rc;
+
+ rc = dps310_calculate_temp(data);
+ if (rc < 0)
+ return rc;
+
+ *val = rc;
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ rc = dps310_get_temp_precision(data);
+ if (rc < 0)
+ return rc;
+
+ *val = rc;
+ return IIO_VAL_INT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int dps310_read_raw(struct iio_dev *iio,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct dps310_data *data = iio_priv(iio);
+
+ switch (chan->type) {
+ case IIO_PRESSURE:
+ return dps310_read_pressure(data, val, val2, mask);
+
+ case IIO_TEMP:
+ return dps310_read_temp(data, val, val2, mask);
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static void dps310_reset(void *action_data)
+{
+ struct dps310_data *data = action_data;
+
+ dps310_reset_wait(data);
+}
+
+static const struct regmap_config dps310_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .writeable_reg = dps310_is_writeable_reg,
+ .volatile_reg = dps310_is_volatile_reg,
+ .cache_type = REGCACHE_RBTREE,
+ .max_register = 0x62, /* No documentation available on this register */
+};
+
+static const struct iio_info dps310_info = {
+ .read_raw = dps310_read_raw,
+ .write_raw = dps310_write_raw,
+};
+
+static int dps310_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct dps310_data *data;
+ struct iio_dev *iio;
+ int rc;
+
+ iio = devm_iio_device_alloc(&client->dev, sizeof(*data));
+ if (!iio)
+ return -ENOMEM;
+
+ data = iio_priv(iio);
+ data->client = client;
+ mutex_init(&data->lock);
+
+ iio->name = id->name;
+ iio->channels = dps310_channels;
+ iio->num_channels = ARRAY_SIZE(dps310_channels);
+ iio->info = &dps310_info;
+ iio->modes = INDIO_DIRECT_MODE;
+
+ data->regmap = devm_regmap_init_i2c(client, &dps310_regmap_config);
+ if (IS_ERR(data->regmap))
+ return PTR_ERR(data->regmap);
+
+ /* Register to run the device reset when the device is removed */
+ rc = devm_add_action_or_reset(&client->dev, dps310_reset, data);
+ if (rc)
+ return rc;
+
+ rc = dps310_startup(data);
+ if (rc)
+ return rc;
+
+ rc = devm_iio_device_register(&client->dev, iio);
+ if (rc)
+ return rc;
+
+ i2c_set_clientdata(client, iio);
+
+ return 0;
+}
+
+static const struct i2c_device_id dps310_id[] = {
+ { DPS310_DEV_NAME, 0 },
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, dps310_id);
+
+static const struct acpi_device_id dps310_acpi_match[] = {
+ { "IFX3100" },
+ {}
+};
+MODULE_DEVICE_TABLE(acpi, dps310_acpi_match);
+
+static struct i2c_driver dps310_driver = {
+ .driver = {
+ .name = DPS310_DEV_NAME,
+ .acpi_match_table = dps310_acpi_match,
+ },
+ .probe = dps310_probe,
+ .id_table = dps310_id,
+};
+module_i2c_driver(dps310_driver);
+
+MODULE_AUTHOR("Joel Stanley <joel@jms.id.au>");
+MODULE_DESCRIPTION("Infineon DPS310 pressure and temperature sensor");
+MODULE_LICENSE("GPL v2");