[PATCH v6 0/9] Add support for pressure sensor Bosch BMP380

[PATCH v6 0/9] Add support for pressure sensor Bosch BMP380

[Angel Iglesias]

This patchset adds BMP380 variant to the already existing drivers for
the Bosch BMP180/280 pressure sensors.

Patch 1 reorder local variables declarations following reverse xmas tree
conventions, as suggested by Andy Shevchenko <andy.shevchenko@gmail.com>.
Patch 2 migrates existing code to use FIELD_GET/FIELD_PREP and GENMASK
utilities.
Patch 3 is a minor refactor of the function that loads bmp280 calibration
params, taking advantage of the data contiguity in memory.
Patch 4 is a minor refactor simplifying driver initialization logic
to facilitate the integration of the new sensor variant extending the
information stored in the "chip_info" struct.
Patch 5 fixes DMA unsafe regmap_bulk_* calls reported by Jonathan Cameron
<jic23@kernel.org>.
Patch 6 is a minor refactor reordering device match tables declarations in
forward order as suggested by Andy Shevchenko <andy.shevchenko@gmail.com>.
Patch 7 adds the basic logic to initialize and read measurements from
the sensor.
Patch 8 adds references and sensor id to the devicetree bindings docs.
Patch 9 adds advanced configurable features such as sampling frequency
and IIR filter through the IIO sysfs ABI.

Changes in v6:
 - Introduced patch 1 reordering local variables declarations.
 - Patch 2 is separated form v5 patch 1, separating initialization
   refactor from migration to FIELD_GET, FIELD_PREP and GENMASK.
 - Patch 3 backports a refactor made to bmp280 calibration load
   on v5 patch 2.
 - Introduced patch 6 reordering i2c device match tables declarations.
 - Revised patch 7 and 9 and smoothed transition to patch 9 moving some
   code on v5 patch 5 to patch 7 (BMP380 basic enablement).
 - Cleaned error handling of regmap calls thorough patches.
 - Changed formula used to handle IIR filter on patch 9 following feedback
   made by Andy Shevchenko <andy.shevchenko@gmail.com>.
 - Made union with data buffers on patch 5 anonymous (suggested by Andy
   Shevchenko <andy.shevchenko@gmail.com>)
 - Improved handling of be16 and le16 data on patch 5 integrating changes
   suggested by Jonathan Cameron <jic23@kernel.org>.

Changes in v5:
 - Moved dt bindings patch (previously patch 2/5) to 4/5 to preserve
   tree coherence as suggested by Jonathan Cameron <jic23@kernel.org>
 - Patch 1: Simplified initial oversampling values assignation.
 - Patch 1: Updated codepaths for bmp180 and bmp280 to use FIELD_GET and
   FIELD_GET helpers. Migrated compatible masks to use GENMASK.
 - Patch 2: Store DMA-safe buffers on the device data struct instead of
   using dynamic allocations for calibration buffers.
   Thanks Jonathan Cameron <jic23@kernel.org>.
 - Patch 3: Fixed small typos
 - Patch 3: Fixed incompatible division on 32-bit machines reported by
   Andy Shevchenko <andy.shevchenko@gmail.com> and kernel test robot
   <lkp@intel.com>.
 - Patch 3: Fixed inconsistent use of "x" and "X" declaring constants.
 - Patch 5: Dropped incorrect reported-by tag on changelog message.
 - Patch 5: Fixed typos on various comments.

Changes in v4:
 - Patch 4 and 2: Merged v3 patch 2 (Kconfig refs update) into this patch.
 - Patch 3: Added patch fixing unsafe DMA regmap_bulk_* calls reported by
   Jonathan Cameron <jic23@kernel.org>.
 - Patch 4: Fixed DMA unsafe buffers used on regmap_bulk_* calls reported
   by Jonathan Cameron <jic23@kernel.org>.

Changes in v3:
 - Patch 2: Fixed incorrect abbreviation.
 - Patch 3: use dev_err_probe helper to handle error initializing sensor.
 - Patch 4: Fixed kernel test robot warning provoked by missing include.
 - Patch 4: Fixed bug reported by Dan Carpenter <dan.carpenter@oracle.com>.
 - Patch 5: Fixed formatting and typos on multiple comments.
 - Patch 5: Fixed missing boolean initialization reported by
   Andy Shevchenko <andy.shevchenko@gmail.com>.
 - Patch 5: Replaced duplicated comments with a single comment containing
   a brief explantation in a shared location.
 - Patch 5: Dropped incorrect use of unlikely macro.

Changes in v2:
 - Added patch 2 updating Kconfig with references to new sensor.
 - Patch 3 adds changes proposed by Jonathan Cameron <jic23@kernel.org>
   to declutter and unify configuration logic for the different sensors
   extending "chip_info" struct with default configuration parameters.
 - Patch 4: store temperature and pressure adc values on 3 byte array
   instead of using the type __le32. Uses function get_unaligned_le24
   to convert the little-endian encoded 3 byte value to an integer.
 - Patch 4: drops custom macro le16_from_bytes and use get_unaligned_le16.
 - Patch 4: generate masks using GENMASK macro.
 - Patch 4: use FIELD_PREP to generate bitfields for registries.
 - Patch 4: dropped stray formatting change.
 - Patch 5: adds sanity checks in bmp280_read_raw for channel properties
   only available in the BMP380.
 - Patch 5: on bmp280_write_* checks if a problem occurred committing new
   configuration and tries to restore previous working configuration
   to keep the sensor in a previous working state.
 - Patch 5: refactored bmp380_chip_config to only check for configuration
   errors when a configuration change is detected.
 - Patch 5: improved invalid configuration detection on BMP380 restarting
   measurement loop to force a new measurement after the configuration is
   updated.

Previous patch version available on:
 https://lore.kernel.org/all/cover.1659872590.git.ang.iglesiasg@gmail.com/

Angel Iglesias (9):
  iio: pressure: bmp280: reorder local variables following reverse xmas
    tree
  iio: pressure: bmp280: use FIELD_GET, FIELD_PREP and GENMASK
  iio: pressure: bmp280: Simplify bmp280 calibration data reading
  iio: pressure: bmp280: simplify driver initialization logic
  iio: pressure: bmp280: Fix alignment for DMA safety
  iio: pressure: bmp280: reorder i2c device tables declarations
  iio: pressure: bmp280: Add support for BMP380 sensor family
  dt-bindings: iio: pressure: bmp085: Add BMP380 compatible string
  iio: pressure: bmp280: Add more tunable config parameters for BMP380

 .../bindings/iio/pressure/bmp085.yaml         |   4 +-
 drivers/iio/pressure/Kconfig                  |   6 +-
 drivers/iio/pressure/bmp280-core.c            | 962 +++++++++++++++---
 drivers/iio/pressure/bmp280-i2c.c             |  15 +-
 drivers/iio/pressure/bmp280-regmap.c          |  55 +
 drivers/iio/pressure/bmp280-spi.c             |   5 +
 drivers/iio/pressure/bmp280.h                 | 164 ++-
 7 files changed, 1018 insertions(+), 193 deletions(-)


base-commit: 2f61ff8272967c9bdcba810aa978170814b08f7c
-- 
2.37.3

[PATCH v6 1/9] iio: pressure: bmp280: reorder local variables following reverse xmas tree

[Angel Iglesias]

Reordered definitions of local variables following the reverse christmas
tree convention.

Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
---
 drivers/iio/pressure/bmp280-core.c | 65 +++++++++++++++---------------
 1 file changed, 33 insertions(+), 32 deletions(-)

diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index fe7aa81e7cc9..42b29f30e9d1 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -151,13 +151,14 @@ static int bmp280_read_calib(struct bmp280_data *data,
 			     struct bmp280_calib *calib,
 			     unsigned int chip)
 {
-	int ret;
+	__le16 p_buf[BMP280_COMP_PRESS_REG_COUNT / 2];
+	__le16 t_buf[BMP280_COMP_TEMP_REG_COUNT / 2];
+	struct device *dev = data->dev;
 	unsigned int tmp;
 	__le16 l16;
 	__be16 b16;
-	struct device *dev = data->dev;
-	__le16 t_buf[BMP280_COMP_TEMP_REG_COUNT / 2];
-	__le16 p_buf[BMP280_COMP_PRESS_REG_COUNT / 2];
+	int ret;
+
 
 	/* Read temperature calibration values. */
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
@@ -261,8 +262,8 @@ static int bmp280_read_calib(struct bmp280_data *data,
 static u32 bmp280_compensate_humidity(struct bmp280_data *data,
 				      s32 adc_humidity)
 {
-	s32 var;
 	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))
@@ -286,8 +287,8 @@ static u32 bmp280_compensate_humidity(struct bmp280_data *data,
 static s32 bmp280_compensate_temp(struct bmp280_data *data,
 				  s32 adc_temp)
 {
-	s32 var1, var2;
 	struct bmp280_calib *calib = &data->calib.bmp280;
+	s32 var1, var2;
 
 	var1 = (((adc_temp >> 3) - ((s32)calib->T1 << 1)) *
 		((s32)calib->T2)) >> 11;
@@ -309,8 +310,8 @@ static s32 bmp280_compensate_temp(struct bmp280_data *data,
 static u32 bmp280_compensate_press(struct bmp280_data *data,
 				   s32 adc_press)
 {
-	s64 var1, var2, p;
 	struct bmp280_calib *calib = &data->calib.bmp280;
+	s64 var1, var2, p;
 
 	var1 = ((s64)data->t_fine) - 128000;
 	var2 = var1 * var1 * (s64)calib->P6;
@@ -335,9 +336,9 @@ static u32 bmp280_compensate_press(struct bmp280_data *data,
 static int bmp280_read_temp(struct bmp280_data *data,
 			    int *val)
 {
-	int ret;
-	__be32 tmp = 0;
 	s32 adc_temp, comp_temp;
+	__be32 tmp = 0;
+	int ret;
 
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB, &tmp, 3);
 	if (ret < 0) {
@@ -368,10 +369,10 @@ static int bmp280_read_temp(struct bmp280_data *data,
 static int bmp280_read_press(struct bmp280_data *data,
 			     int *val, int *val2)
 {
-	int ret;
+	u32 comp_press;
 	__be32 tmp = 0;
 	s32 adc_press;
-	u32 comp_press;
+	int ret;
 
 	/* Read and compensate temperature so we get a reading of t_fine. */
 	ret = bmp280_read_temp(data, NULL);
@@ -400,10 +401,10 @@ static int bmp280_read_press(struct bmp280_data *data,
 
 static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
 {
+	u32 comp_humidity;
+	s32 adc_humidity;
 	__be16 tmp;
 	int ret;
-	s32 adc_humidity;
-	u32 comp_humidity;
 
 	/* Read and compensate temperature so we get a reading of t_fine. */
 	ret = bmp280_read_temp(data, NULL);
@@ -433,8 +434,8 @@ 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);
+	int ret;
 
 	pm_runtime_get_sync(data->dev);
 	mutex_lock(&data->lock);
@@ -490,9 +491,9 @@ static int bmp280_read_raw(struct iio_dev *indio_dev,
 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;
+	int i;
 
 	for (i = 0; i < n; i++) {
 		if (avail[i] == val) {
@@ -507,9 +508,9 @@ static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data,
 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;
+	int i;
 
 	for (i = 0; i < n; i++) {
 		if (avail[i] == val) {
@@ -524,9 +525,9 @@ static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data,
 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;
+	int i;
 
 	for (i = 0; i < n; i++) {
 		if (avail[i] == val) {
@@ -542,8 +543,8 @@ 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);
+	int ret = 0;
 
 	switch (mask) {
 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
@@ -610,9 +611,9 @@ static const struct iio_info bmp280_info = {
 
 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);
+	int ret;
 
 	ret = regmap_write_bits(data->regmap, BMP280_REG_CTRL_MEAS,
 				 BMP280_OSRS_TEMP_MASK |
@@ -653,8 +654,8 @@ static const struct bmp280_chip_info bmp280_chip_info = {
 
 static int bme280_chip_config(struct bmp280_data *data)
 {
-	int ret;
 	u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1);
+	int ret;
 
 	/*
 	 * Oversampling of humidity must be set before oversampling of
@@ -687,10 +688,10 @@ static const struct bmp280_chip_info bme280_chip_info = {
 
 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;
+	int ret;
 
 	if (data->use_eoc)
 		reinit_completion(&data->done);
@@ -751,9 +752,9 @@ static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
 static int bmp180_read_calib(struct bmp280_data *data,
 			     struct bmp180_calib *calib)
 {
+	__be16 buf[BMP180_REG_CALIB_COUNT / 2];
 	int ret;
 	int i;
-	__be16 buf[BMP180_REG_CALIB_COUNT / 2];
 
 	ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf,
 			       sizeof(buf));
@@ -793,8 +794,8 @@ static int bmp180_read_calib(struct bmp280_data *data,
  */
 static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp)
 {
-	s32 x1, x2;
 	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);
@@ -805,8 +806,8 @@ static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp)
 
 static int bmp180_read_temp(struct bmp280_data *data, int *val)
 {
-	int ret;
 	s32 adc_temp, comp_temp;
+	int ret;
 
 	ret = bmp180_read_adc_temp(data, &adc_temp);
 	if (ret)
@@ -828,9 +829,9 @@ static int bmp180_read_temp(struct bmp280_data *data, int *val)
 
 static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
 {
-	int ret;
-	__be32 tmp = 0;
 	u8 oss = data->oversampling_press;
+	__be32 tmp = 0;
+	int ret;
 
 	ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss));
 	if (ret)
@@ -852,11 +853,11 @@ static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
  */
 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;
-	s32 oss = data->oversampling_press;
-	struct bmp180_calib *calib = &data->calib.bmp180;
 
 	b6 = data->t_fine - 4000;
 	x1 = (calib->B2 * (b6 * b6 >> 12)) >> 11;
@@ -883,9 +884,9 @@ static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press)
 static int bmp180_read_press(struct bmp280_data *data,
 			     int *val, int *val2)
 {
-	int ret;
-	s32 adc_press;
 	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);
@@ -990,11 +991,11 @@ int bmp280_common_probe(struct device *dev,
 			const char *name,
 			int irq)
 {
-	int ret;
 	struct iio_dev *indio_dev;
 	struct bmp280_data *data;
-	unsigned int chip_id;
 	struct gpio_desc *gpiod;
+	unsigned int chip_id;
+	int ret;
 
 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
 	if (!indio_dev)
-- 
2.37.3

[PATCH v6 2/9] iio: pressure: bmp280: use FIELD_GET, FIELD_PREP and GENMASK

[Angel Iglesias]

Cleaned and simplified register values construction and extraction
converting to use FIELD_PREP and FIELD_GET macros.

Replaced hardcoded bit masks with GENMASK macro.

Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
---
 drivers/iio/pressure/bmp280-core.c | 25 ++++++----
 drivers/iio/pressure/bmp280.h      | 78 ++++++++++++++++--------------
 2 files changed, 57 insertions(+), 46 deletions(-)

diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index 42b29f30e9d1..0ba4ff999f33 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -16,6 +16,8 @@
 
 #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>
@@ -242,7 +244,7 @@ static int bmp280_read_calib(struct bmp280_data *data,
 		dev_err(dev, "failed to read H5 comp value\n");
 		return ret;
 	}
-	calib->H5 = sign_extend32(((le16_to_cpu(l16) >> 4) & 0xfff), 11);
+	calib->H5 = sign_extend32(FIELD_GET(BMP280_COMP_H5_MASK, le16_to_cpu(l16)), 11);
 
 	ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp);
 	if (ret < 0) {
@@ -346,7 +348,7 @@ static int bmp280_read_temp(struct bmp280_data *data,
 		return ret;
 	}
 
-	adc_temp = be32_to_cpu(tmp) >> 12;
+	adc_temp = FIELD_GET(BMP280_MEAS_TRIM_MASK, be32_to_cpu(tmp));
 	if (adc_temp == BMP280_TEMP_SKIPPED) {
 		/* reading was skipped */
 		dev_err(data->dev, "reading temperature skipped\n");
@@ -385,7 +387,7 @@ static int bmp280_read_press(struct bmp280_data *data,
 		return ret;
 	}
 
-	adc_press = be32_to_cpu(tmp) >> 12;
+	adc_press = FIELD_GET(BMP280_MEAS_TRIM_MASK, be32_to_cpu(tmp));
 	if (adc_press == BMP280_PRESS_SKIPPED) {
 		/* reading was skipped */
 		dev_err(data->dev, "reading pressure skipped\n");
@@ -611,8 +613,8 @@ static const struct iio_info bmp280_info = {
 
 static int bmp280_chip_config(struct bmp280_data *data)
 {
-	u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) |
-		  BMP280_OSRS_PRESS_X(data->oversampling_press + 1);
+	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,
@@ -654,7 +656,7 @@ static const struct bmp280_chip_info bmp280_chip_info = {
 
 static int bme280_chip_config(struct bmp280_data *data)
 {
-	u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1);
+	u8 osrs = FIELD_PREP(BMP280_OSRS_HUMIDITY_MASK, data->oversampling_humid + 1);
 	int ret;
 
 	/*
@@ -711,7 +713,7 @@ static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
 		if (!ret)
 			dev_err(data->dev, "timeout waiting for completion\n");
 	} else {
-		if (ctrl_meas == BMP180_MEAS_TEMP)
+		if (FIELD_GET(BMP180_MEAS_CTRL_MASK, ctrl_meas) == BMP180_MEAS_TEMP)
 			delay_us = 4500;
 		else
 			delay_us =
@@ -736,7 +738,9 @@ static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
 	__be16 tmp;
 	int ret;
 
-	ret = bmp180_measure(data, BMP180_MEAS_TEMP);
+	ret = bmp180_measure(data,
+			     FIELD_PREP(BMP180_MEAS_CTRL_MASK, BMP180_MEAS_TEMP) |
+			     BMP180_MEAS_SCO);
 	if (ret)
 		return ret;
 
@@ -833,7 +837,10 @@ static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
 	__be32 tmp = 0;
 	int ret;
 
-	ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss));
+	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;
 
diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
index 57ba0e85db91..4a501836d27a 100644
--- a/drivers/iio/pressure/bmp280.h
+++ b/drivers/iio/pressure/bmp280.h
@@ -13,6 +13,9 @@
 #define BMP280_REG_PRESS_LSB		0xF8
 #define BMP280_REG_PRESS_MSB		0xF7
 
+/* Helper mask to truncate excess 12 bits on pressure and temp readings */
+#define BMP280_MEAS_TRIM_MASK		GENMASK(31, 12)
+
 #define BMP280_REG_CONFIG		0xF5
 #define BMP280_REG_CTRL_MEAS		0xF4
 #define BMP280_REG_STATUS		0xF3
@@ -32,44 +35,43 @@
 #define BMP280_REG_COMP_PRESS_START	0x8E
 #define BMP280_COMP_PRESS_REG_COUNT	18
 
-#define BMP280_FILTER_MASK		(BIT(4) | BIT(3) | BIT(2))
+#define BMP280_COMP_H5_MASK		GENMASK(15, 4)
+
+#define BMP280_FILTER_MASK		GENMASK(4, 2)
 #define BMP280_FILTER_OFF		0
-#define BMP280_FILTER_2X		BIT(2)
-#define BMP280_FILTER_4X		BIT(3)
-#define BMP280_FILTER_8X		(BIT(3) | BIT(2))
-#define BMP280_FILTER_16X		BIT(4)
+#define BMP280_FILTER_2X		1
+#define BMP280_FILTER_4X		2
+#define BMP280_FILTER_8X		3
+#define BMP280_FILTER_16X		4
 
-#define BMP280_OSRS_HUMIDITY_MASK	(BIT(2) | BIT(1) | BIT(0))
-#define BMP280_OSRS_HUMIDITIY_X(osrs_h)	((osrs_h) << 0)
+#define BMP280_OSRS_HUMIDITY_MASK	GENMASK(2, 0)
 #define BMP280_OSRS_HUMIDITY_SKIP	0
-#define BMP280_OSRS_HUMIDITY_1X		BMP280_OSRS_HUMIDITIY_X(1)
-#define BMP280_OSRS_HUMIDITY_2X		BMP280_OSRS_HUMIDITIY_X(2)
-#define BMP280_OSRS_HUMIDITY_4X		BMP280_OSRS_HUMIDITIY_X(3)
-#define BMP280_OSRS_HUMIDITY_8X		BMP280_OSRS_HUMIDITIY_X(4)
-#define BMP280_OSRS_HUMIDITY_16X	BMP280_OSRS_HUMIDITIY_X(5)
+#define BMP280_OSRS_HUMIDITY_1X		1
+#define BMP280_OSRS_HUMIDITY_2X		2
+#define BMP280_OSRS_HUMIDITY_4X		3
+#define BMP280_OSRS_HUMIDITY_8X		4
+#define BMP280_OSRS_HUMIDITY_16X	5
 
-#define BMP280_OSRS_TEMP_MASK		(BIT(7) | BIT(6) | BIT(5))
+#define BMP280_OSRS_TEMP_MASK		GENMASK(7, 5)
 #define BMP280_OSRS_TEMP_SKIP		0
-#define BMP280_OSRS_TEMP_X(osrs_t)	((osrs_t) << 5)
-#define BMP280_OSRS_TEMP_1X		BMP280_OSRS_TEMP_X(1)
-#define BMP280_OSRS_TEMP_2X		BMP280_OSRS_TEMP_X(2)
-#define BMP280_OSRS_TEMP_4X		BMP280_OSRS_TEMP_X(3)
-#define BMP280_OSRS_TEMP_8X		BMP280_OSRS_TEMP_X(4)
-#define BMP280_OSRS_TEMP_16X		BMP280_OSRS_TEMP_X(5)
-
-#define BMP280_OSRS_PRESS_MASK		(BIT(4) | BIT(3) | BIT(2))
+#define BMP280_OSRS_TEMP_1X		1
+#define BMP280_OSRS_TEMP_2X		2
+#define BMP280_OSRS_TEMP_4X		3
+#define BMP280_OSRS_TEMP_8X		4
+#define BMP280_OSRS_TEMP_16X		5
+
+#define BMP280_OSRS_PRESS_MASK		GENMASK(4, 2)
 #define BMP280_OSRS_PRESS_SKIP		0
-#define BMP280_OSRS_PRESS_X(osrs_p)	((osrs_p) << 2)
-#define BMP280_OSRS_PRESS_1X		BMP280_OSRS_PRESS_X(1)
-#define BMP280_OSRS_PRESS_2X		BMP280_OSRS_PRESS_X(2)
-#define BMP280_OSRS_PRESS_4X		BMP280_OSRS_PRESS_X(3)
-#define BMP280_OSRS_PRESS_8X		BMP280_OSRS_PRESS_X(4)
-#define BMP280_OSRS_PRESS_16X		BMP280_OSRS_PRESS_X(5)
-
-#define BMP280_MODE_MASK		(BIT(1) | BIT(0))
+#define BMP280_OSRS_PRESS_1X		1
+#define BMP280_OSRS_PRESS_2X		2
+#define BMP280_OSRS_PRESS_4X		3
+#define BMP280_OSRS_PRESS_8X		4
+#define BMP280_OSRS_PRESS_16X		5
+
+#define BMP280_MODE_MASK		GENMASK(1, 0)
 #define BMP280_MODE_SLEEP		0
-#define BMP280_MODE_FORCED		BIT(0)
-#define BMP280_MODE_NORMAL		(BIT(1) | BIT(0))
+#define BMP280_MODE_FORCED		1
+#define BMP280_MODE_NORMAL		3
 
 /* BMP180 specific registers */
 #define BMP180_REG_OUT_XLSB		0xF8
@@ -79,13 +81,15 @@
 #define BMP180_REG_CALIB_START		0xAA
 #define BMP180_REG_CALIB_COUNT		22
 
+#define BMP180_MEAS_CTRL_MASK		GENMASK(4, 0)
+#define BMP180_MEAS_TEMP		0x0E
+#define BMP180_MEAS_PRESS		0x14
 #define BMP180_MEAS_SCO			BIT(5)
-#define BMP180_MEAS_TEMP		(0x0E | BMP180_MEAS_SCO)
-#define BMP180_MEAS_PRESS_X(oss)	((oss) << 6 | 0x14 | BMP180_MEAS_SCO)
-#define BMP180_MEAS_PRESS_1X		BMP180_MEAS_PRESS_X(0)
-#define BMP180_MEAS_PRESS_2X		BMP180_MEAS_PRESS_X(1)
-#define BMP180_MEAS_PRESS_4X		BMP180_MEAS_PRESS_X(2)
-#define BMP180_MEAS_PRESS_8X		BMP180_MEAS_PRESS_X(3)
+#define BMP180_OSRS_PRESS_MASK		GENMASK(7, 6)
+#define BMP180_MEAS_PRESS_1X		0
+#define BMP180_MEAS_PRESS_2X		1
+#define BMP180_MEAS_PRESS_4X		2
+#define BMP180_MEAS_PRESS_8X		3
 
 /* BMP180 and BMP280 common registers */
 #define BMP280_REG_CTRL_MEAS		0xF4
-- 
2.37.3

Re: [PATCH v6 2/9] iio: pressure: bmp280: use FIELD_GET, FIELD_PREP and GENMASK

[Jonathan Cameron]

On Tue, 13 Sep 2022 01:45:49 +0200
Angel Iglesias <ang.iglesiasg@gmail.com> wrote:

> Cleaned and simplified register values construction and extraction
> converting to use FIELD_PREP and FIELD_GET macros.
> 
> Replaced hardcoded bit masks with GENMASK macro.
> 
> Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
Random thought whilst checking this..

I wonder how many users a FIELD_GET_SIGNED() would have
with the assumption it returned a sign extended value...

Anyhow, I'm picking up these patches as I look through
them (mainly because I'm waiting for a late flight and not
sure how far I'll get!)

So applied up to here so far...

Jonathan

> ---
>  drivers/iio/pressure/bmp280-core.c | 25 ++++++----
>  drivers/iio/pressure/bmp280.h      | 78 ++++++++++++++++--------------
>  2 files changed, 57 insertions(+), 46 deletions(-)
> 
> diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
> index 42b29f30e9d1..0ba4ff999f33 100644
> --- a/drivers/iio/pressure/bmp280-core.c
> +++ b/drivers/iio/pressure/bmp280-core.c
> @@ -16,6 +16,8 @@
>  
>  #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>
> @@ -242,7 +244,7 @@ static int bmp280_read_calib(struct bmp280_data *data,
>  		dev_err(dev, "failed to read H5 comp value\n");
>  		return ret;
>  	}
> -	calib->H5 = sign_extend32(((le16_to_cpu(l16) >> 4) & 0xfff), 11);
> +	calib->H5 = sign_extend32(FIELD_GET(BMP280_COMP_H5_MASK, le16_to_cpu(l16)), 11);
>  
>  	ret = regmap_read(data->regmap, BMP280_REG_COMP_H6, &tmp);
>  	if (ret < 0) {
> @@ -346,7 +348,7 @@ static int bmp280_read_temp(struct bmp280_data *data,
>  		return ret;
>  	}
>  
> -	adc_temp = be32_to_cpu(tmp) >> 12;
> +	adc_temp = FIELD_GET(BMP280_MEAS_TRIM_MASK, be32_to_cpu(tmp));
>  	if (adc_temp == BMP280_TEMP_SKIPPED) {
>  		/* reading was skipped */
>  		dev_err(data->dev, "reading temperature skipped\n");
> @@ -385,7 +387,7 @@ static int bmp280_read_press(struct bmp280_data *data,
>  		return ret;
>  	}
>  
> -	adc_press = be32_to_cpu(tmp) >> 12;
> +	adc_press = FIELD_GET(BMP280_MEAS_TRIM_MASK, be32_to_cpu(tmp));
>  	if (adc_press == BMP280_PRESS_SKIPPED) {
>  		/* reading was skipped */
>  		dev_err(data->dev, "reading pressure skipped\n");
> @@ -611,8 +613,8 @@ static const struct iio_info bmp280_info = {
>  
>  static int bmp280_chip_config(struct bmp280_data *data)
>  {
> -	u8 osrs = BMP280_OSRS_TEMP_X(data->oversampling_temp + 1) |
> -		  BMP280_OSRS_PRESS_X(data->oversampling_press + 1);
> +	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,
> @@ -654,7 +656,7 @@ static const struct bmp280_chip_info bmp280_chip_info = {
>  
>  static int bme280_chip_config(struct bmp280_data *data)
>  {
> -	u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1);
> +	u8 osrs = FIELD_PREP(BMP280_OSRS_HUMIDITY_MASK, data->oversampling_humid + 1);
>  	int ret;
>  
>  	/*
> @@ -711,7 +713,7 @@ static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
>  		if (!ret)
>  			dev_err(data->dev, "timeout waiting for completion\n");
>  	} else {
> -		if (ctrl_meas == BMP180_MEAS_TEMP)
> +		if (FIELD_GET(BMP180_MEAS_CTRL_MASK, ctrl_meas) == BMP180_MEAS_TEMP)
>  			delay_us = 4500;
>  		else
>  			delay_us =
> @@ -736,7 +738,9 @@ static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
>  	__be16 tmp;
>  	int ret;
>  
> -	ret = bmp180_measure(data, BMP180_MEAS_TEMP);
> +	ret = bmp180_measure(data,
> +			     FIELD_PREP(BMP180_MEAS_CTRL_MASK, BMP180_MEAS_TEMP) |
> +			     BMP180_MEAS_SCO);
>  	if (ret)
>  		return ret;
>  
> @@ -833,7 +837,10 @@ static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
>  	__be32 tmp = 0;
>  	int ret;
>  
> -	ret = bmp180_measure(data, BMP180_MEAS_PRESS_X(oss));
> +	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;
>  
> diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
> index 57ba0e85db91..4a501836d27a 100644
> --- a/drivers/iio/pressure/bmp280.h
> +++ b/drivers/iio/pressure/bmp280.h
> @@ -13,6 +13,9 @@
>  #define BMP280_REG_PRESS_LSB		0xF8
>  #define BMP280_REG_PRESS_MSB		0xF7
>  
> +/* Helper mask to truncate excess 12 bits on pressure and temp readings */
> +#define BMP280_MEAS_TRIM_MASK		GENMASK(31, 12)
> +
>  #define BMP280_REG_CONFIG		0xF5
>  #define BMP280_REG_CTRL_MEAS		0xF4
>  #define BMP280_REG_STATUS		0xF3
> @@ -32,44 +35,43 @@
>  #define BMP280_REG_COMP_PRESS_START	0x8E
>  #define BMP280_COMP_PRESS_REG_COUNT	18
>  
> -#define BMP280_FILTER_MASK		(BIT(4) | BIT(3) | BIT(2))
> +#define BMP280_COMP_H5_MASK		GENMASK(15, 4)
> +
> +#define BMP280_FILTER_MASK		GENMASK(4, 2)
>  #define BMP280_FILTER_OFF		0
> -#define BMP280_FILTER_2X		BIT(2)
> -#define BMP280_FILTER_4X		BIT(3)
> -#define BMP280_FILTER_8X		(BIT(3) | BIT(2))
> -#define BMP280_FILTER_16X		BIT(4)
> +#define BMP280_FILTER_2X		1
> +#define BMP280_FILTER_4X		2
> +#define BMP280_FILTER_8X		3
> +#define BMP280_FILTER_16X		4
>  
> -#define BMP280_OSRS_HUMIDITY_MASK	(BIT(2) | BIT(1) | BIT(0))
> -#define BMP280_OSRS_HUMIDITIY_X(osrs_h)	((osrs_h) << 0)
> +#define BMP280_OSRS_HUMIDITY_MASK	GENMASK(2, 0)
>  #define BMP280_OSRS_HUMIDITY_SKIP	0
> -#define BMP280_OSRS_HUMIDITY_1X		BMP280_OSRS_HUMIDITIY_X(1)
> -#define BMP280_OSRS_HUMIDITY_2X		BMP280_OSRS_HUMIDITIY_X(2)
> -#define BMP280_OSRS_HUMIDITY_4X		BMP280_OSRS_HUMIDITIY_X(3)
> -#define BMP280_OSRS_HUMIDITY_8X		BMP280_OSRS_HUMIDITIY_X(4)
> -#define BMP280_OSRS_HUMIDITY_16X	BMP280_OSRS_HUMIDITIY_X(5)
> +#define BMP280_OSRS_HUMIDITY_1X		1
> +#define BMP280_OSRS_HUMIDITY_2X		2
> +#define BMP280_OSRS_HUMIDITY_4X		3
> +#define BMP280_OSRS_HUMIDITY_8X		4
> +#define BMP280_OSRS_HUMIDITY_16X	5
>  
> -#define BMP280_OSRS_TEMP_MASK		(BIT(7) | BIT(6) | BIT(5))
> +#define BMP280_OSRS_TEMP_MASK		GENMASK(7, 5)
>  #define BMP280_OSRS_TEMP_SKIP		0
> -#define BMP280_OSRS_TEMP_X(osrs_t)	((osrs_t) << 5)
> -#define BMP280_OSRS_TEMP_1X		BMP280_OSRS_TEMP_X(1)
> -#define BMP280_OSRS_TEMP_2X		BMP280_OSRS_TEMP_X(2)
> -#define BMP280_OSRS_TEMP_4X		BMP280_OSRS_TEMP_X(3)
> -#define BMP280_OSRS_TEMP_8X		BMP280_OSRS_TEMP_X(4)
> -#define BMP280_OSRS_TEMP_16X		BMP280_OSRS_TEMP_X(5)
> -
> -#define BMP280_OSRS_PRESS_MASK		(BIT(4) | BIT(3) | BIT(2))
> +#define BMP280_OSRS_TEMP_1X		1
> +#define BMP280_OSRS_TEMP_2X		2
> +#define BMP280_OSRS_TEMP_4X		3
> +#define BMP280_OSRS_TEMP_8X		4
> +#define BMP280_OSRS_TEMP_16X		5
> +
> +#define BMP280_OSRS_PRESS_MASK		GENMASK(4, 2)
>  #define BMP280_OSRS_PRESS_SKIP		0
> -#define BMP280_OSRS_PRESS_X(osrs_p)	((osrs_p) << 2)
> -#define BMP280_OSRS_PRESS_1X		BMP280_OSRS_PRESS_X(1)
> -#define BMP280_OSRS_PRESS_2X		BMP280_OSRS_PRESS_X(2)
> -#define BMP280_OSRS_PRESS_4X		BMP280_OSRS_PRESS_X(3)
> -#define BMP280_OSRS_PRESS_8X		BMP280_OSRS_PRESS_X(4)
> -#define BMP280_OSRS_PRESS_16X		BMP280_OSRS_PRESS_X(5)
> -
> -#define BMP280_MODE_MASK		(BIT(1) | BIT(0))
> +#define BMP280_OSRS_PRESS_1X		1
> +#define BMP280_OSRS_PRESS_2X		2
> +#define BMP280_OSRS_PRESS_4X		3
> +#define BMP280_OSRS_PRESS_8X		4
> +#define BMP280_OSRS_PRESS_16X		5
> +
> +#define BMP280_MODE_MASK		GENMASK(1, 0)
>  #define BMP280_MODE_SLEEP		0
> -#define BMP280_MODE_FORCED		BIT(0)
> -#define BMP280_MODE_NORMAL		(BIT(1) | BIT(0))
> +#define BMP280_MODE_FORCED		1
> +#define BMP280_MODE_NORMAL		3
>  
>  /* BMP180 specific registers */
>  #define BMP180_REG_OUT_XLSB		0xF8
> @@ -79,13 +81,15 @@
>  #define BMP180_REG_CALIB_START		0xAA
>  #define BMP180_REG_CALIB_COUNT		22
>  
> +#define BMP180_MEAS_CTRL_MASK		GENMASK(4, 0)
> +#define BMP180_MEAS_TEMP		0x0E
> +#define BMP180_MEAS_PRESS		0x14
>  #define BMP180_MEAS_SCO			BIT(5)
> -#define BMP180_MEAS_TEMP		(0x0E | BMP180_MEAS_SCO)
> -#define BMP180_MEAS_PRESS_X(oss)	((oss) << 6 | 0x14 | BMP180_MEAS_SCO)
> -#define BMP180_MEAS_PRESS_1X		BMP180_MEAS_PRESS_X(0)
> -#define BMP180_MEAS_PRESS_2X		BMP180_MEAS_PRESS_X(1)
> -#define BMP180_MEAS_PRESS_4X		BMP180_MEAS_PRESS_X(2)
> -#define BMP180_MEAS_PRESS_8X		BMP180_MEAS_PRESS_X(3)
> +#define BMP180_OSRS_PRESS_MASK		GENMASK(7, 6)
> +#define BMP180_MEAS_PRESS_1X		0
> +#define BMP180_MEAS_PRESS_2X		1
> +#define BMP180_MEAS_PRESS_4X		2
> +#define BMP180_MEAS_PRESS_8X		3
>  
>  /* BMP180 and BMP280 common registers */
>  #define BMP280_REG_CTRL_MEAS		0xF4

[PATCH v6 3/9] iio: pressure: bmp280: Simplify bmp280 calibration data reading

[Angel Iglesias]

On bmp280 and bme280, the temperature and pressure calibration parameters
are available on a contiguous memory region. Considering this arrangement,
simplified the calibration reading function by using only one buffer
to read in batch temperature and pressure registers.

Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
---
 drivers/iio/pressure/bmp280-core.c | 58 ++++++++++++------------------
 drivers/iio/pressure/bmp280.h      |  3 ++
 2 files changed, 26 insertions(+), 35 deletions(-)

diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index 0ba4ff999f33..4793bcd9f0b3 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -128,8 +128,7 @@ struct bmp280_chip_info {
  * 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 };
+enum { T1, T2, T3, P1, P2, P3, P4, P5, P6, P7, P8, P9 };
 
 static const struct iio_chan_spec bmp280_channels[] = {
 	{
@@ -153,8 +152,7 @@ static int bmp280_read_calib(struct bmp280_data *data,
 			     struct bmp280_calib *calib,
 			     unsigned int chip)
 {
-	__le16 p_buf[BMP280_COMP_PRESS_REG_COUNT / 2];
-	__le16 t_buf[BMP280_COMP_TEMP_REG_COUNT / 2];
+	__le16 c_buf[BMP280_CONTIGUOUS_CALIB_REGS / 2];
 	struct device *dev = data->dev;
 	unsigned int tmp;
 	__le16 l16;
@@ -162,43 +160,33 @@ static int bmp280_read_calib(struct bmp280_data *data,
 	int ret;
 
 
-	/* Read temperature calibration values. */
+	/* Read temperature and pressure calibration values. */
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
-			       t_buf, BMP280_COMP_TEMP_REG_COUNT);
+			       c_buf, sizeof(c_buf));
 	if (ret < 0) {
 		dev_err(data->dev,
-			"failed to read temperature calibration parameters\n");
+			"failed to read temperature and pressure calibration parameters\n");
 		return ret;
 	}
 
-	/* Toss the temperature calibration data into the entropy pool */
-	add_device_randomness(t_buf, sizeof(t_buf));
-
-	calib->T1 = le16_to_cpu(t_buf[T1]);
-	calib->T2 = le16_to_cpu(t_buf[T2]);
-	calib->T3 = le16_to_cpu(t_buf[T3]);
-
-	/* Read pressure calibration values. */
-	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START,
-			       p_buf, BMP280_COMP_PRESS_REG_COUNT);
-	if (ret < 0) {
-		dev_err(data->dev,
-			"failed to read pressure calibration parameters\n");
-		return ret;
-	}
-
-	/* Toss the pressure calibration data into the entropy pool */
-	add_device_randomness(p_buf, sizeof(p_buf));
-
-	calib->P1 = le16_to_cpu(p_buf[P1]);
-	calib->P2 = le16_to_cpu(p_buf[P2]);
-	calib->P3 = le16_to_cpu(p_buf[P3]);
-	calib->P4 = le16_to_cpu(p_buf[P4]);
-	calib->P5 = le16_to_cpu(p_buf[P5]);
-	calib->P6 = le16_to_cpu(p_buf[P6]);
-	calib->P7 = le16_to_cpu(p_buf[P7]);
-	calib->P8 = le16_to_cpu(p_buf[P8]);
-	calib->P9 = le16_to_cpu(p_buf[P9]);
+	/* Toss the temperature and pressure calibration data into the entropy pool */
+	add_device_randomness(c_buf, sizeof(c_buf));
+
+	/* Parse temperature calibration values. */
+	calib->T1 = le16_to_cpu(c_buf[T1]);
+	calib->T2 = le16_to_cpu(c_buf[T2]);
+	calib->T3 = le16_to_cpu(c_buf[T3]);
+
+	/* Parse pressure calibration values. */
+	calib->P1 = le16_to_cpu(c_buf[P1]);
+	calib->P2 = le16_to_cpu(c_buf[P2]);
+	calib->P3 = le16_to_cpu(c_buf[P3]);
+	calib->P4 = le16_to_cpu(c_buf[P4]);
+	calib->P5 = le16_to_cpu(c_buf[P5]);
+	calib->P6 = le16_to_cpu(c_buf[P6]);
+	calib->P7 = le16_to_cpu(c_buf[P7]);
+	calib->P8 = le16_to_cpu(c_buf[P8]);
+	calib->P9 = le16_to_cpu(c_buf[P9]);
 
 	/*
 	 * Read humidity calibration values.
diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
index 4a501836d27a..03a539223417 100644
--- a/drivers/iio/pressure/bmp280.h
+++ b/drivers/iio/pressure/bmp280.h
@@ -37,6 +37,9 @@
 
 #define BMP280_COMP_H5_MASK		GENMASK(15, 4)
 
+#define BMP280_CONTIGUOUS_CALIB_REGS	(BMP280_COMP_TEMP_REG_COUNT + \
+					 BMP280_COMP_PRESS_REG_COUNT)
+
 #define BMP280_FILTER_MASK		GENMASK(4, 2)
 #define BMP280_FILTER_OFF		0
 #define BMP280_FILTER_2X		1
-- 
2.37.3

Re: [PATCH v6 3/9] iio: pressure: bmp280: Simplify bmp280 calibration data reading

[Jonathan Cameron]

On Tue, 13 Sep 2022 01:46:42 +0200
Angel Iglesias <ang.iglesiasg@gmail.com> wrote:

> On bmp280 and bme280, the temperature and pressure calibration parameters
> are available on a contiguous memory region. Considering this arrangement,
> simplified the calibration reading function by using only one buffer
> to read in batch temperature and pressure registers.
> 
> Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
Applied.  Apparently we have a plane, so I'll stop here for now...

Jonathan

> ---
>  drivers/iio/pressure/bmp280-core.c | 58 ++++++++++++------------------
>  drivers/iio/pressure/bmp280.h      |  3 ++
>  2 files changed, 26 insertions(+), 35 deletions(-)
> 
> diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
> index 0ba4ff999f33..4793bcd9f0b3 100644
> --- a/drivers/iio/pressure/bmp280-core.c
> +++ b/drivers/iio/pressure/bmp280-core.c
> @@ -128,8 +128,7 @@ struct bmp280_chip_info {
>   * 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 };
> +enum { T1, T2, T3, P1, P2, P3, P4, P5, P6, P7, P8, P9 };
>  
>  static const struct iio_chan_spec bmp280_channels[] = {
>  	{
> @@ -153,8 +152,7 @@ static int bmp280_read_calib(struct bmp280_data *data,
>  			     struct bmp280_calib *calib,
>  			     unsigned int chip)
>  {
> -	__le16 p_buf[BMP280_COMP_PRESS_REG_COUNT / 2];
> -	__le16 t_buf[BMP280_COMP_TEMP_REG_COUNT / 2];
> +	__le16 c_buf[BMP280_CONTIGUOUS_CALIB_REGS / 2];
>  	struct device *dev = data->dev;
>  	unsigned int tmp;
>  	__le16 l16;
> @@ -162,43 +160,33 @@ static int bmp280_read_calib(struct bmp280_data *data,
>  	int ret;
>  
>  
> -	/* Read temperature calibration values. */
> +	/* Read temperature and pressure calibration values. */
>  	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
> -			       t_buf, BMP280_COMP_TEMP_REG_COUNT);
> +			       c_buf, sizeof(c_buf));
>  	if (ret < 0) {
>  		dev_err(data->dev,
> -			"failed to read temperature calibration parameters\n");
> +			"failed to read temperature and pressure calibration parameters\n");
>  		return ret;
>  	}
>  
> -	/* Toss the temperature calibration data into the entropy pool */
> -	add_device_randomness(t_buf, sizeof(t_buf));
> -
> -	calib->T1 = le16_to_cpu(t_buf[T1]);
> -	calib->T2 = le16_to_cpu(t_buf[T2]);
> -	calib->T3 = le16_to_cpu(t_buf[T3]);
> -
> -	/* Read pressure calibration values. */
> -	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START,
> -			       p_buf, BMP280_COMP_PRESS_REG_COUNT);
> -	if (ret < 0) {
> -		dev_err(data->dev,
> -			"failed to read pressure calibration parameters\n");
> -		return ret;
> -	}
> -
> -	/* Toss the pressure calibration data into the entropy pool */
> -	add_device_randomness(p_buf, sizeof(p_buf));
> -
> -	calib->P1 = le16_to_cpu(p_buf[P1]);
> -	calib->P2 = le16_to_cpu(p_buf[P2]);
> -	calib->P3 = le16_to_cpu(p_buf[P3]);
> -	calib->P4 = le16_to_cpu(p_buf[P4]);
> -	calib->P5 = le16_to_cpu(p_buf[P5]);
> -	calib->P6 = le16_to_cpu(p_buf[P6]);
> -	calib->P7 = le16_to_cpu(p_buf[P7]);
> -	calib->P8 = le16_to_cpu(p_buf[P8]);
> -	calib->P9 = le16_to_cpu(p_buf[P9]);
> +	/* Toss the temperature and pressure calibration data into the entropy pool */
> +	add_device_randomness(c_buf, sizeof(c_buf));
> +
> +	/* Parse temperature calibration values. */
> +	calib->T1 = le16_to_cpu(c_buf[T1]);
> +	calib->T2 = le16_to_cpu(c_buf[T2]);
> +	calib->T3 = le16_to_cpu(c_buf[T3]);
> +
> +	/* Parse pressure calibration values. */
> +	calib->P1 = le16_to_cpu(c_buf[P1]);
> +	calib->P2 = le16_to_cpu(c_buf[P2]);
> +	calib->P3 = le16_to_cpu(c_buf[P3]);
> +	calib->P4 = le16_to_cpu(c_buf[P4]);
> +	calib->P5 = le16_to_cpu(c_buf[P5]);
> +	calib->P6 = le16_to_cpu(c_buf[P6]);
> +	calib->P7 = le16_to_cpu(c_buf[P7]);
> +	calib->P8 = le16_to_cpu(c_buf[P8]);
> +	calib->P9 = le16_to_cpu(c_buf[P9]);
>  
>  	/*
>  	 * Read humidity calibration values.
> diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
> index 4a501836d27a..03a539223417 100644
> --- a/drivers/iio/pressure/bmp280.h
> +++ b/drivers/iio/pressure/bmp280.h
> @@ -37,6 +37,9 @@
>  
>  #define BMP280_COMP_H5_MASK		GENMASK(15, 4)
>  
> +#define BMP280_CONTIGUOUS_CALIB_REGS	(BMP280_COMP_TEMP_REG_COUNT + \
> +					 BMP280_COMP_PRESS_REG_COUNT)
> +
>  #define BMP280_FILTER_MASK		GENMASK(4, 2)
>  #define BMP280_FILTER_OFF		0
>  #define BMP280_FILTER_2X		1

[PATCH v6 4/9] iio: pressure: bmp280: simplify driver initialization logic

[Angel Iglesias]

Simplified common initialization logic of different sensor types
unifying calibration and initial configuration recovery.

Default config param values of each sensor type are stored inside
chip_info structure and used to initialize sensor data struct instance.

The helper functions for read each sensor type calibration are converted
to a callback available on the chip_info struct.

Separated bme280 specific calibration code from bmp280 function. Dropped
the additional chip_id argument in bmp280 code as is not longer required.
Now both bmp280/bme280 calibration function use same signature as bmp180.

Suggested-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
---
 drivers/iio/pressure/bmp280-core.c | 126 +++++++++++++++++++----------
 1 file changed, 83 insertions(+), 43 deletions(-)

diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index 4793bcd9f0b3..203623d32032 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -109,19 +109,28 @@ struct bmp280_data {
 };
 
 struct bmp280_chip_info {
+	unsigned int id_reg;
+
+	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;
 
 	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 *);
 };
 
 /*
@@ -148,15 +157,10 @@ static const struct iio_chan_spec bmp280_channels[] = {
 	},
 };
 
-static int bmp280_read_calib(struct bmp280_data *data,
-			     struct bmp280_calib *calib,
-			     unsigned int chip)
+static int bmp280_read_calib(struct bmp280_data *data)
 {
+	struct bmp280_calib *calib = &data->calib.bmp280;
 	__le16 c_buf[BMP280_CONTIGUOUS_CALIB_REGS / 2];
-	struct device *dev = data->dev;
-	unsigned int tmp;
-	__le16 l16;
-	__be16 b16;
 	int ret;
 
 
@@ -188,6 +192,25 @@ static int bmp280_read_calib(struct bmp280_data *data,
 	calib->P8 = le16_to_cpu(c_buf[P8]);
 	calib->P9 = le16_to_cpu(c_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;
+	__le16 l16;
+	__be16 b16;
+	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
@@ -195,8 +218,6 @@ static int bmp280_read_calib(struct bmp280_data *data,
 	 * value separately and sometimes do some bit shifting...
 	 * Humidity data is only available on BME280.
 	 */
-	if (chip != BME280_CHIP_ID)
-		return 0;
 
 	ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &tmp);
 	if (ret < 0) {
@@ -631,15 +652,32 @@ static int bmp280_chip_config(struct bmp280_data *data)
 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,
+	.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)
@@ -661,19 +699,27 @@ static int bme280_chip_config(struct bmp280_data *data)
 }
 
 static const struct bmp280_chip_info bme280_chip_info = {
+	.id_reg = BMP280_REG_ID,
+	.start_up_time = 2000,
+	.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,
 };
 
 static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
@@ -741,9 +787,9 @@ static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
 	return 0;
 }
 
-static int bmp180_read_calib(struct bmp280_data *data,
-			     struct bmp180_calib *calib)
+static int bmp180_read_calib(struct bmp280_data *data)
 {
+	struct bmp180_calib *calib = &data->calib.bmp180;
 	__be16 buf[BMP180_REG_CALIB_COUNT / 2];
 	int ret;
 	int i;
@@ -909,17 +955,24 @@ 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,
+	.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)
@@ -986,6 +1039,7 @@ int bmp280_common_probe(struct device *dev,
 			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;
@@ -1007,30 +1061,25 @@ int bmp280_common_probe(struct device *dev,
 
 	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;
+		chip_info = &bmp180_chip_info;
 		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;
+		chip_info = &bmp280_chip_info;
 		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;
+		chip_info = &bme280_chip_info;
 		break;
 	default:
 		return -EINVAL;
 	}
+	data->chip_info = chip_info;
+
+	/* Apply initial values from chip info structure */
+	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->start_up_time = chip_info->start_up_time;
 
 	/* Bring up regulators */
 	regulator_bulk_set_supply_names(data->supplies,
@@ -1067,7 +1116,8 @@ int bmp280_common_probe(struct device *dev,
 	}
 
 	data->regmap = regmap;
-	ret = regmap_read(regmap, BMP280_REG_ID, &chip_id);
+
+	ret = regmap_read(regmap, data->chip_info->id_reg, &chip_id);
 	if (ret < 0)
 		return ret;
 	if (chip_id != chip) {
@@ -1087,21 +1137,11 @@ int bmp280_common_probe(struct device *dev,
 	 * non-volatile memory during production". Let's read them out at probe
 	 * time once. They will not change.
 	 */
-	if (chip_id  == BMP180_CHIP_ID) {
-		ret = bmp180_read_calib(data, &data->calib.bmp180);
-		if (ret < 0) {
-			dev_err(data->dev,
-				"failed to read calibration coefficients\n");
-			return ret;
-		}
-	} else if (chip_id == BMP280_CHIP_ID || chip_id == BME280_CHIP_ID) {
-		ret = bmp280_read_calib(data, &data->calib.bmp280, chip_id);
-		if (ret < 0) {
-			dev_err(data->dev,
-				"failed to read calibration coefficients\n");
-			return ret;
-		}
-	}
+
+	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
-- 
2.37.3

Re: [PATCH v6 4/9] iio: pressure: bmp280: simplify driver initialization logic

[Jonathan Cameron]

On Tue, 13 Sep 2022 01:47:31 +0200
Angel Iglesias <ang.iglesiasg@gmail.com> wrote:

> Simplified common initialization logic of different sensor types
> unifying calibration and initial configuration recovery.
> 
> Default config param values of each sensor type are stored inside
> chip_info structure and used to initialize sensor data struct instance.
> 
> The helper functions for read each sensor type calibration are converted
> to a callback available on the chip_info struct.
> 
> Separated bme280 specific calibration code from bmp280 function. Dropped
> the additional chip_id argument in bmp280 code as is not longer required.
> Now both bmp280/bme280 calibration function use same signature as bmp180.
> 
> Suggested-by: Jonathan Cameron <jic23@kernel.org>
> Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
Applied
> ---
>  drivers/iio/pressure/bmp280-core.c | 126 +++++++++++++++++++----------
>  1 file changed, 83 insertions(+), 43 deletions(-)
> 
> diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
> index 4793bcd9f0b3..203623d32032 100644
> --- a/drivers/iio/pressure/bmp280-core.c
> +++ b/drivers/iio/pressure/bmp280-core.c
> @@ -109,19 +109,28 @@ struct bmp280_data {
>  };
>  
>  struct bmp280_chip_info {
> +	unsigned int id_reg;
> +
> +	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;
>  
>  	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 *);
>  };
>  
>  /*
> @@ -148,15 +157,10 @@ static const struct iio_chan_spec bmp280_channels[] = {
>  	},
>  };
>  
> -static int bmp280_read_calib(struct bmp280_data *data,
> -			     struct bmp280_calib *calib,
> -			     unsigned int chip)
> +static int bmp280_read_calib(struct bmp280_data *data)
>  {
> +	struct bmp280_calib *calib = &data->calib.bmp280;
>  	__le16 c_buf[BMP280_CONTIGUOUS_CALIB_REGS / 2];
> -	struct device *dev = data->dev;
> -	unsigned int tmp;
> -	__le16 l16;
> -	__be16 b16;
>  	int ret;
>  
>  
> @@ -188,6 +192,25 @@ static int bmp280_read_calib(struct bmp280_data *data,
>  	calib->P8 = le16_to_cpu(c_buf[P8]);
>  	calib->P9 = le16_to_cpu(c_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;
> +	__le16 l16;
> +	__be16 b16;
> +	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
> @@ -195,8 +218,6 @@ static int bmp280_read_calib(struct bmp280_data *data,
>  	 * value separately and sometimes do some bit shifting...
>  	 * Humidity data is only available on BME280.
>  	 */
> -	if (chip != BME280_CHIP_ID)
> -		return 0;
>  
>  	ret = regmap_read(data->regmap, BMP280_REG_COMP_H1, &tmp);
>  	if (ret < 0) {
> @@ -631,15 +652,32 @@ static int bmp280_chip_config(struct bmp280_data *data)
>  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,
> +	.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)
> @@ -661,19 +699,27 @@ static int bme280_chip_config(struct bmp280_data *data)
>  }
>  
>  static const struct bmp280_chip_info bme280_chip_info = {
> +	.id_reg = BMP280_REG_ID,
> +	.start_up_time = 2000,
> +	.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,
>  };
>  
>  static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
> @@ -741,9 +787,9 @@ static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
>  	return 0;
>  }
>  
> -static int bmp180_read_calib(struct bmp280_data *data,
> -			     struct bmp180_calib *calib)
> +static int bmp180_read_calib(struct bmp280_data *data)
>  {
> +	struct bmp180_calib *calib = &data->calib.bmp180;
>  	__be16 buf[BMP180_REG_CALIB_COUNT / 2];
>  	int ret;
>  	int i;
> @@ -909,17 +955,24 @@ 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,
> +	.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)
> @@ -986,6 +1039,7 @@ int bmp280_common_probe(struct device *dev,
>  			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;
> @@ -1007,30 +1061,25 @@ int bmp280_common_probe(struct device *dev,
>  
>  	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;
> +		chip_info = &bmp180_chip_info;
>  		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;
> +		chip_info = &bmp280_chip_info;
>  		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;
> +		chip_info = &bme280_chip_info;
>  		break;
>  	default:
>  		return -EINVAL;
>  	}
> +	data->chip_info = chip_info;
> +
> +	/* Apply initial values from chip info structure */
> +	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->start_up_time = chip_info->start_up_time;
>  
>  	/* Bring up regulators */
>  	regulator_bulk_set_supply_names(data->supplies,
> @@ -1067,7 +1116,8 @@ int bmp280_common_probe(struct device *dev,
>  	}
>  
>  	data->regmap = regmap;
> -	ret = regmap_read(regmap, BMP280_REG_ID, &chip_id);
> +
> +	ret = regmap_read(regmap, data->chip_info->id_reg, &chip_id);
>  	if (ret < 0)
>  		return ret;
>  	if (chip_id != chip) {
> @@ -1087,21 +1137,11 @@ int bmp280_common_probe(struct device *dev,
>  	 * non-volatile memory during production". Let's read them out at probe
>  	 * time once. They will not change.
>  	 */
> -	if (chip_id  == BMP180_CHIP_ID) {
> -		ret = bmp180_read_calib(data, &data->calib.bmp180);
> -		if (ret < 0) {
> -			dev_err(data->dev,
> -				"failed to read calibration coefficients\n");
> -			return ret;
> -		}
> -	} else if (chip_id == BMP280_CHIP_ID || chip_id == BME280_CHIP_ID) {
> -		ret = bmp280_read_calib(data, &data->calib.bmp280, chip_id);
> -		if (ret < 0) {
> -			dev_err(data->dev,
> -				"failed to read calibration coefficients\n");
> -			return ret;
> -		}
> -	}
> +
> +	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

[PATCH v6 5/9] iio: pressure: bmp280: Fix alignment for DMA safety

[Angel Iglesias]

Adds DMA-safe buffers to driver data struct to store raw data from sensors

The multiple buffers used thorough the driver share the same memory
allocated as part of the device data instance. The union containing
the buffers is aligned to allow safe usage with DMA operations, such
as regmap bulk read calls.

Updated measurement and calibration reading functions to use the safe
DMA buffers.

Suggested-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
---
 drivers/iio/pressure/bmp280-core.c | 131 ++++++++++++++++-------------
 drivers/iio/pressure/bmp280.h      |   4 +-
 2 files changed, 76 insertions(+), 59 deletions(-)

diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index 203623d32032..b6a16a580962 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -32,6 +32,8 @@
 #include <linux/pm_runtime.h>
 #include <linux/random.h>
 
+#include <asm/unaligned.h>
+
 #include "bmp280.h"
 
 /*
@@ -106,6 +108,21 @@ struct bmp280_data {
 	 * 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];
+		/* Miscellaneous, endianess-aware data buffers */
+		__le16 le16;
+		__be16 be16;
+	} __aligned(IIO_DMA_MINALIGN);
 };
 
 struct bmp280_chip_info {
@@ -160,13 +177,12 @@ static const struct iio_chan_spec bmp280_channels[] = {
 static int bmp280_read_calib(struct bmp280_data *data)
 {
 	struct bmp280_calib *calib = &data->calib.bmp280;
-	__le16 c_buf[BMP280_CONTIGUOUS_CALIB_REGS / 2];
 	int ret;
 
 
 	/* Read temperature and pressure calibration values. */
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
-			       c_buf, sizeof(c_buf));
+			       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");
@@ -174,23 +190,23 @@ static int bmp280_read_calib(struct bmp280_data *data)
 	}
 
 	/* Toss the temperature and pressure calibration data into the entropy pool */
-	add_device_randomness(c_buf, sizeof(c_buf));
+	add_device_randomness(data->bmp280_cal_buf, sizeof(data->bmp280_cal_buf));
 
 	/* Parse temperature calibration values. */
-	calib->T1 = le16_to_cpu(c_buf[T1]);
-	calib->T2 = le16_to_cpu(c_buf[T2]);
-	calib->T3 = le16_to_cpu(c_buf[T3]);
+	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(c_buf[P1]);
-	calib->P2 = le16_to_cpu(c_buf[P2]);
-	calib->P3 = le16_to_cpu(c_buf[P3]);
-	calib->P4 = le16_to_cpu(c_buf[P4]);
-	calib->P5 = le16_to_cpu(c_buf[P5]);
-	calib->P6 = le16_to_cpu(c_buf[P6]);
-	calib->P7 = le16_to_cpu(c_buf[P7]);
-	calib->P8 = le16_to_cpu(c_buf[P8]);
-	calib->P9 = le16_to_cpu(c_buf[P9]);
+	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;
 }
@@ -200,8 +216,6 @@ static int bme280_read_calib(struct bmp280_data *data)
 	struct bmp280_calib *calib = &data->calib.bmp280;
 	struct device *dev = data->dev;
 	unsigned int tmp;
-	__le16 l16;
-	__be16 b16;
 	int ret;
 
 	/* Load shared calibration params with bmp280 first */
@@ -226,12 +240,13 @@ static int bme280_read_calib(struct bmp280_data *data)
 	}
 	calib->H1 = tmp;
 
-	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &l16, 2);
+	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(l16), 15);
+	calib->H2 = sign_extend32(le16_to_cpu(data->le16), 15);
 
 	ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &tmp);
 	if (ret < 0) {
@@ -240,20 +255,22 @@ static int bme280_read_calib(struct bmp280_data *data)
 	}
 	calib->H3 = tmp;
 
-	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &b16, 2);
+	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(b16) >> 4) & 0xff0) |
-				  (be16_to_cpu(b16) & 0xf), 11);
+	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, &l16, 2);
+	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(l16)), 11);
+	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) {
@@ -348,16 +365,16 @@ static int bmp280_read_temp(struct bmp280_data *data,
 			    int *val)
 {
 	s32 adc_temp, comp_temp;
-	__be32 tmp = 0;
 	int ret;
 
-	ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB, &tmp, 3);
+	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, be32_to_cpu(tmp));
+	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");
@@ -381,7 +398,6 @@ static int bmp280_read_press(struct bmp280_data *data,
 			     int *val, int *val2)
 {
 	u32 comp_press;
-	__be32 tmp = 0;
 	s32 adc_press;
 	int ret;
 
@@ -390,13 +406,14 @@ static int bmp280_read_press(struct bmp280_data *data,
 	if (ret < 0)
 		return ret;
 
-	ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB, &tmp, 3);
+	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, be32_to_cpu(tmp));
+	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");
@@ -414,7 +431,6 @@ static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
 {
 	u32 comp_humidity;
 	s32 adc_humidity;
-	__be16 tmp;
 	int ret;
 
 	/* Read and compensate temperature so we get a reading of t_fine. */
@@ -422,13 +438,14 @@ static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
 	if (ret < 0)
 		return ret;
 
-	ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB, &tmp, 2);
+	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(tmp);
+	adc_humidity = be16_to_cpu(data->be16);
 	if (adc_humidity == BMP280_HUMIDITY_SKIPPED) {
 		/* reading was skipped */
 		dev_err(data->dev, "reading humidity skipped\n");
@@ -769,7 +786,6 @@ static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
 
 static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
 {
-	__be16 tmp;
 	int ret;
 
 	ret = bmp180_measure(data,
@@ -778,11 +794,12 @@ static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
 	if (ret)
 		return ret;
 
-	ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, &tmp, 2);
+	ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB,
+			       &data->be16, sizeof(data->be16));
 	if (ret)
 		return ret;
 
-	*val = be16_to_cpu(tmp);
+	*val = be16_to_cpu(data->be16);
 
 	return 0;
 }
@@ -790,36 +807,36 @@ static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
 static int bmp180_read_calib(struct bmp280_data *data)
 {
 	struct bmp180_calib *calib = &data->calib.bmp180;
-	__be16 buf[BMP180_REG_CALIB_COUNT / 2];
 	int ret;
 	int i;
 
-	ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf,
-			       sizeof(buf));
+	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(buf); i++) {
-		if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(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(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]);
+	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;
 }
@@ -868,7 +885,6 @@ static int bmp180_read_temp(struct bmp280_data *data, int *val)
 static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
 {
 	u8 oss = data->oversampling_press;
-	__be32 tmp = 0;
 	int ret;
 
 	ret = bmp180_measure(data,
@@ -878,11 +894,12 @@ static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
 	if (ret)
 		return ret;
 
-	ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, &tmp, 3);
+	ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB,
+			       data->buf, sizeof(data->buf));
 	if (ret)
 		return ret;
 
-	*val = (be32_to_cpu(tmp) >> 8) >> (8 - oss);
+	*val = get_unaligned_be24(data->buf) >> (8 - oss);
 
 	return 0;
 }
diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
index 03a539223417..c9214a7e5cc6 100644
--- a/drivers/iio/pressure/bmp280.h
+++ b/drivers/iio/pressure/bmp280.h
@@ -13,8 +13,8 @@
 #define BMP280_REG_PRESS_LSB		0xF8
 #define BMP280_REG_PRESS_MSB		0xF7
 
-/* Helper mask to truncate excess 12 bits on pressure and temp readings */
-#define BMP280_MEAS_TRIM_MASK		GENMASK(31, 12)
+/* Helper mask to truncate excess 4 bits on pressure and temp readings */
+#define BMP280_MEAS_TRIM_MASK		GENMASK(24, 4)
 
 #define BMP280_REG_CONFIG		0xF5
 #define BMP280_REG_CTRL_MEAS		0xF4
-- 
2.37.3

Re: [PATCH v6 5/9] iio: pressure: bmp280: Fix alignment for DMA safety

[Jonathan Cameron]

On Tue, 13 Sep 2022 01:48:21 +0200
Angel Iglesias <ang.iglesiasg@gmail.com> wrote:

> Adds DMA-safe buffers to driver data struct to store raw data from sensors
> 
> The multiple buffers used thorough the driver share the same memory
> allocated as part of the device data instance. The union containing
> the buffers is aligned to allow safe usage with DMA operations, such
> as regmap bulk read calls.
> 
> Updated measurement and calibration reading functions to use the safe
> DMA buffers.
> 
> Suggested-by: Jonathan Cameron <jic23@kernel.org>
> Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
Applied
> ---
>  drivers/iio/pressure/bmp280-core.c | 131 ++++++++++++++++-------------
>  drivers/iio/pressure/bmp280.h      |   4 +-
>  2 files changed, 76 insertions(+), 59 deletions(-)
> 
> diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
> index 203623d32032..b6a16a580962 100644
> --- a/drivers/iio/pressure/bmp280-core.c
> +++ b/drivers/iio/pressure/bmp280-core.c
> @@ -32,6 +32,8 @@
>  #include <linux/pm_runtime.h>
>  #include <linux/random.h>
>  
> +#include <asm/unaligned.h>
> +
>  #include "bmp280.h"
>  
>  /*
> @@ -106,6 +108,21 @@ struct bmp280_data {
>  	 * 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];
> +		/* Miscellaneous, endianess-aware data buffers */
> +		__le16 le16;
> +		__be16 be16;
> +	} __aligned(IIO_DMA_MINALIGN);
>  };
>  
>  struct bmp280_chip_info {
> @@ -160,13 +177,12 @@ static const struct iio_chan_spec bmp280_channels[] = {
>  static int bmp280_read_calib(struct bmp280_data *data)
>  {
>  	struct bmp280_calib *calib = &data->calib.bmp280;
> -	__le16 c_buf[BMP280_CONTIGUOUS_CALIB_REGS / 2];
>  	int ret;
>  
>  
>  	/* Read temperature and pressure calibration values. */
>  	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
> -			       c_buf, sizeof(c_buf));
> +			       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");
> @@ -174,23 +190,23 @@ static int bmp280_read_calib(struct bmp280_data *data)
>  	}
>  
>  	/* Toss the temperature and pressure calibration data into the entropy pool */
> -	add_device_randomness(c_buf, sizeof(c_buf));
> +	add_device_randomness(data->bmp280_cal_buf, sizeof(data->bmp280_cal_buf));
>  
>  	/* Parse temperature calibration values. */
> -	calib->T1 = le16_to_cpu(c_buf[T1]);
> -	calib->T2 = le16_to_cpu(c_buf[T2]);
> -	calib->T3 = le16_to_cpu(c_buf[T3]);
> +	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(c_buf[P1]);
> -	calib->P2 = le16_to_cpu(c_buf[P2]);
> -	calib->P3 = le16_to_cpu(c_buf[P3]);
> -	calib->P4 = le16_to_cpu(c_buf[P4]);
> -	calib->P5 = le16_to_cpu(c_buf[P5]);
> -	calib->P6 = le16_to_cpu(c_buf[P6]);
> -	calib->P7 = le16_to_cpu(c_buf[P7]);
> -	calib->P8 = le16_to_cpu(c_buf[P8]);
> -	calib->P9 = le16_to_cpu(c_buf[P9]);
> +	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;
>  }
> @@ -200,8 +216,6 @@ static int bme280_read_calib(struct bmp280_data *data)
>  	struct bmp280_calib *calib = &data->calib.bmp280;
>  	struct device *dev = data->dev;
>  	unsigned int tmp;
> -	__le16 l16;
> -	__be16 b16;
>  	int ret;
>  
>  	/* Load shared calibration params with bmp280 first */
> @@ -226,12 +240,13 @@ static int bme280_read_calib(struct bmp280_data *data)
>  	}
>  	calib->H1 = tmp;
>  
> -	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H2, &l16, 2);
> +	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(l16), 15);
> +	calib->H2 = sign_extend32(le16_to_cpu(data->le16), 15);
>  
>  	ret = regmap_read(data->regmap, BMP280_REG_COMP_H3, &tmp);
>  	if (ret < 0) {
> @@ -240,20 +255,22 @@ static int bme280_read_calib(struct bmp280_data *data)
>  	}
>  	calib->H3 = tmp;
>  
> -	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_H4, &b16, 2);
> +	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(b16) >> 4) & 0xff0) |
> -				  (be16_to_cpu(b16) & 0xf), 11);
> +	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, &l16, 2);
> +	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(l16)), 11);
> +	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) {
> @@ -348,16 +365,16 @@ static int bmp280_read_temp(struct bmp280_data *data,
>  			    int *val)
>  {
>  	s32 adc_temp, comp_temp;
> -	__be32 tmp = 0;
>  	int ret;
>  
> -	ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB, &tmp, 3);
> +	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, be32_to_cpu(tmp));
> +	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");
> @@ -381,7 +398,6 @@ static int bmp280_read_press(struct bmp280_data *data,
>  			     int *val, int *val2)
>  {
>  	u32 comp_press;
> -	__be32 tmp = 0;
>  	s32 adc_press;
>  	int ret;
>  
> @@ -390,13 +406,14 @@ static int bmp280_read_press(struct bmp280_data *data,
>  	if (ret < 0)
>  		return ret;
>  
> -	ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB, &tmp, 3);
> +	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, be32_to_cpu(tmp));
> +	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");
> @@ -414,7 +431,6 @@ static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
>  {
>  	u32 comp_humidity;
>  	s32 adc_humidity;
> -	__be16 tmp;
>  	int ret;
>  
>  	/* Read and compensate temperature so we get a reading of t_fine. */
> @@ -422,13 +438,14 @@ static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
>  	if (ret < 0)
>  		return ret;
>  
> -	ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB, &tmp, 2);
> +	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(tmp);
> +	adc_humidity = be16_to_cpu(data->be16);
>  	if (adc_humidity == BMP280_HUMIDITY_SKIPPED) {
>  		/* reading was skipped */
>  		dev_err(data->dev, "reading humidity skipped\n");
> @@ -769,7 +786,6 @@ static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
>  
>  static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
>  {
> -	__be16 tmp;
>  	int ret;
>  
>  	ret = bmp180_measure(data,
> @@ -778,11 +794,12 @@ static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
>  	if (ret)
>  		return ret;
>  
> -	ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, &tmp, 2);
> +	ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB,
> +			       &data->be16, sizeof(data->be16));
>  	if (ret)
>  		return ret;
>  
> -	*val = be16_to_cpu(tmp);
> +	*val = be16_to_cpu(data->be16);
>  
>  	return 0;
>  }
> @@ -790,36 +807,36 @@ static int bmp180_read_adc_temp(struct bmp280_data *data, int *val)
>  static int bmp180_read_calib(struct bmp280_data *data)
>  {
>  	struct bmp180_calib *calib = &data->calib.bmp180;
> -	__be16 buf[BMP180_REG_CALIB_COUNT / 2];
>  	int ret;
>  	int i;
>  
> -	ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf,
> -			       sizeof(buf));
> +	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(buf); i++) {
> -		if (buf[i] == cpu_to_be16(0) || buf[i] == cpu_to_be16(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(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]);
> +	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;
>  }
> @@ -868,7 +885,6 @@ static int bmp180_read_temp(struct bmp280_data *data, int *val)
>  static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
>  {
>  	u8 oss = data->oversampling_press;
> -	__be32 tmp = 0;
>  	int ret;
>  
>  	ret = bmp180_measure(data,
> @@ -878,11 +894,12 @@ static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
>  	if (ret)
>  		return ret;
>  
> -	ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB, &tmp, 3);
> +	ret = regmap_bulk_read(data->regmap, BMP180_REG_OUT_MSB,
> +			       data->buf, sizeof(data->buf));
>  	if (ret)
>  		return ret;
>  
> -	*val = (be32_to_cpu(tmp) >> 8) >> (8 - oss);
> +	*val = get_unaligned_be24(data->buf) >> (8 - oss);
>  
>  	return 0;
>  }
> diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
> index 03a539223417..c9214a7e5cc6 100644
> --- a/drivers/iio/pressure/bmp280.h
> +++ b/drivers/iio/pressure/bmp280.h
> @@ -13,8 +13,8 @@
>  #define BMP280_REG_PRESS_LSB		0xF8
>  #define BMP280_REG_PRESS_MSB		0xF7
>  
> -/* Helper mask to truncate excess 12 bits on pressure and temp readings */
> -#define BMP280_MEAS_TRIM_MASK		GENMASK(31, 12)
> +/* Helper mask to truncate excess 4 bits on pressure and temp readings */
> +#define BMP280_MEAS_TRIM_MASK		GENMASK(24, 4)
>  
>  #define BMP280_REG_CONFIG		0xF5
>  #define BMP280_REG_CTRL_MEAS		0xF4

[PATCH v6 6/9] iio: pressure: bmp280: reorder i2c device tables declarations

[Angel Iglesias]

Change device tables declarations to forward order like in SPI codepath.

Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
---
 drivers/iio/pressure/bmp280-i2c.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/pressure/bmp280-i2c.c b/drivers/iio/pressure/bmp280-i2c.c
index bf4a7a617537..5b51ebfc6f2b 100644
--- a/drivers/iio/pressure/bmp280-i2c.c
+++ b/drivers/iio/pressure/bmp280-i2c.c
@@ -37,18 +37,18 @@ static int bmp280_i2c_probe(struct i2c_client *client,
 }
 
 static const struct of_device_id bmp280_of_i2c_match[] = {
-	{ .compatible = "bosch,bme280", .data = (void *)BME280_CHIP_ID },
-	{ .compatible = "bosch,bmp280", .data = (void *)BMP280_CHIP_ID },
-	{ .compatible = "bosch,bmp180", .data = (void *)BMP180_CHIP_ID },
 	{ .compatible = "bosch,bmp085", .data = (void *)BMP180_CHIP_ID },
+	{ .compatible = "bosch,bmp180", .data = (void *)BMP180_CHIP_ID },
+	{ .compatible = "bosch,bmp280", .data = (void *)BMP280_CHIP_ID },
+	{ .compatible = "bosch,bme280", .data = (void *)BME280_CHIP_ID },
 	{ },
 };
 MODULE_DEVICE_TABLE(of, bmp280_of_i2c_match);
 
 static const struct i2c_device_id bmp280_i2c_id[] = {
-	{"bmp280", BMP280_CHIP_ID },
-	{"bmp180", BMP180_CHIP_ID },
 	{"bmp085", BMP180_CHIP_ID },
+	{"bmp180", BMP180_CHIP_ID },
+	{"bmp280", BMP280_CHIP_ID },
 	{"bme280", BME280_CHIP_ID },
 	{ },
 };
-- 
2.37.3

Re: [PATCH v6 6/9] iio: pressure: bmp280: reorder i2c device tables declarations

[Jonathan Cameron]

On Tue, 13 Sep 2022 01:50:07 +0200
Angel Iglesias <ang.iglesiasg@gmail.com> wrote:

> Change device tables declarations to forward order like in SPI codepath.
> 
> Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
Applied
> ---
>  drivers/iio/pressure/bmp280-i2c.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/iio/pressure/bmp280-i2c.c b/drivers/iio/pressure/bmp280-i2c.c
> index bf4a7a617537..5b51ebfc6f2b 100644
> --- a/drivers/iio/pressure/bmp280-i2c.c
> +++ b/drivers/iio/pressure/bmp280-i2c.c
> @@ -37,18 +37,18 @@ static int bmp280_i2c_probe(struct i2c_client *client,
>  }
>  
>  static const struct of_device_id bmp280_of_i2c_match[] = {
> -	{ .compatible = "bosch,bme280", .data = (void *)BME280_CHIP_ID },
> -	{ .compatible = "bosch,bmp280", .data = (void *)BMP280_CHIP_ID },
> -	{ .compatible = "bosch,bmp180", .data = (void *)BMP180_CHIP_ID },
>  	{ .compatible = "bosch,bmp085", .data = (void *)BMP180_CHIP_ID },
> +	{ .compatible = "bosch,bmp180", .data = (void *)BMP180_CHIP_ID },
> +	{ .compatible = "bosch,bmp280", .data = (void *)BMP280_CHIP_ID },
> +	{ .compatible = "bosch,bme280", .data = (void *)BME280_CHIP_ID },
>  	{ },
>  };
>  MODULE_DEVICE_TABLE(of, bmp280_of_i2c_match);
>  
>  static const struct i2c_device_id bmp280_i2c_id[] = {
> -	{"bmp280", BMP280_CHIP_ID },
> -	{"bmp180", BMP180_CHIP_ID },
>  	{"bmp085", BMP180_CHIP_ID },
> +	{"bmp180", BMP180_CHIP_ID },
> +	{"bmp280", BMP280_CHIP_ID },
>  	{"bme280", BME280_CHIP_ID },
>  	{ },
>  };

[PATCH v6 7/9] iio: pressure: bmp280: Add support for BMP380 sensor family

[Angel Iglesias]

Adds compatibility with the new generation of this sensor, the BMP380.

Includes basic sensor initialization to do pressure and temp
measurements and allows tuning oversampling settings for each channel.

The compensation algorithms are adapted from the device datasheet and
the repository https://github.com/BoschSensortec/BMP3-Sensor-API.

Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
---
 drivers/iio/pressure/Kconfig         |   6 +-
 drivers/iio/pressure/bmp280-core.c   | 386 +++++++++++++++++++++++++++
 drivers/iio/pressure/bmp280-i2c.c    |   5 +
 drivers/iio/pressure/bmp280-regmap.c |  55 ++++
 drivers/iio/pressure/bmp280-spi.c    |   5 +
 drivers/iio/pressure/bmp280.h        | 101 +++++++
 6 files changed, 555 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/pressure/Kconfig b/drivers/iio/pressure/Kconfig
index 0ff756cea63a..c9453389e4f7 100644
--- a/drivers/iio/pressure/Kconfig
+++ b/drivers/iio/pressure/Kconfig
@@ -17,14 +17,14 @@ config ABP060MG
 	  will be called abp060mg.
 
 config BMP280
-	tristate "Bosch Sensortec BMP180/BMP280 pressure sensor I2C driver"
+	tristate "Bosch Sensortec BMP180/BMP280/BMP380 pressure sensor I2C driver"
 	depends on (I2C || SPI_MASTER)
 	select REGMAP
 	select BMP280_I2C if (I2C)
 	select BMP280_SPI if (SPI_MASTER)
 	help
-	  Say yes here to build support for Bosch Sensortec BMP180 and BMP280
-	  pressure and temperature sensors. Also supports the BME280 with
+	  Say yes here to build support for Bosch Sensortec BMP180, BMP280 and
+	  BMP380 pressure and temperature sensors. Also supports the BME280 with
 	  an additional humidity sensor channel.
 
 	  To compile this driver as a module, choose M here: the core module
diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index b6a16a580962..19ac93bb1b83 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -12,6 +12,7 @@
  * 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
+ * https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bmp388-ds001.pdf
  */
 
 #define pr_fmt(fmt) "bmp280: " fmt
@@ -78,6 +79,24 @@ struct bmp280_calib {
 	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"
 };
@@ -94,6 +113,7 @@ struct bmp280_data {
 	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 */
@@ -119,6 +139,7 @@ struct bmp280_data {
 		/* 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;
@@ -156,6 +177,25 @@ struct bmp280_chip_info {
  */
 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,
@@ -739,6 +779,342 @@ static const struct bmp280_chip_info bme280_chip_info = {
 	.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 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(data->regmap, BMP380_REG_ODR,
+				 BMP380_ODRS_MASK, BMP380_ODRS_50HZ);
+	if (ret) {
+		dev_err(data->dev, "failed to write ODR selection register\n");
+		return ret;
+	}
+
+	/* Set filter data */
+	ret = regmap_update_bits(data->regmap, BMP380_REG_CONFIG,
+				 BMP380_FILTER_MASK,
+				 FIELD_PREP(BMP380_FILTER_MASK, BMP380_FILTER_3X));
+	if (ret) {
+		dev_err(data->dev, "failed to write config register\n");
+		return ret;
+	}
+
+	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 struct bmp280_chip_info bmp380_chip_info = {
+	.id_reg = BMP380_REG_ID,
+	.start_up_time = 2000,
+	.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),
+
+	.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 };
@@ -1086,6 +1462,9 @@ int bmp280_common_probe(struct device *dev,
 	case BME280_CHIP_ID:
 		chip_info = &bme280_chip_info;
 		break;
+	case BMP380_CHIP_ID:
+		chip_info = &bmp380_chip_info;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -1143,6 +1522,13 @@ int bmp280_common_probe(struct device *dev,
 		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;
diff --git a/drivers/iio/pressure/bmp280-i2c.c b/drivers/iio/pressure/bmp280-i2c.c
index 5b51ebfc6f2b..0c27211f3ea0 100644
--- a/drivers/iio/pressure/bmp280-i2c.c
+++ b/drivers/iio/pressure/bmp280-i2c.c
@@ -19,6 +19,9 @@ static int bmp280_i2c_probe(struct i2c_client *client,
 	case BME280_CHIP_ID:
 		regmap_config = &bmp280_regmap_config;
 		break;
+	case BMP380_CHIP_ID:
+		regmap_config = &bmp380_regmap_config;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -41,6 +44,7 @@ static const struct of_device_id bmp280_of_i2c_match[] = {
 	{ .compatible = "bosch,bmp180", .data = (void *)BMP180_CHIP_ID },
 	{ .compatible = "bosch,bmp280", .data = (void *)BMP280_CHIP_ID },
 	{ .compatible = "bosch,bme280", .data = (void *)BME280_CHIP_ID },
+	{ .compatible = "bosch,bmp380", .data = (void *)BMP380_CHIP_ID },
 	{ },
 };
 MODULE_DEVICE_TABLE(of, bmp280_of_i2c_match);
@@ -50,6 +54,7 @@ static const struct i2c_device_id bmp280_i2c_id[] = {
 	{"bmp180", BMP180_CHIP_ID },
 	{"bmp280", BMP280_CHIP_ID },
 	{"bme280", BME280_CHIP_ID },
+	{"bmp380", BMP380_CHIP_ID },
 	{ },
 };
 MODULE_DEVICE_TABLE(i2c, bmp280_i2c_id);
diff --git a/drivers/iio/pressure/bmp280-regmap.c b/drivers/iio/pressure/bmp280-regmap.c
index 969698518984..c98c67970265 100644
--- a/drivers/iio/pressure/bmp280-regmap.c
+++ b/drivers/iio/pressure/bmp280-regmap.c
@@ -72,6 +72,49 @@ static bool bmp280_is_volatile_reg(struct device *dev, unsigned int reg)
 	}
 }
 
+static bool bmp380_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case BMP380_REG_CMD:
+	case BMP380_REG_CONFIG:
+	case BMP380_REG_FIFO_CONFIG_1:
+	case BMP380_REG_FIFO_CONFIG_2:
+	case BMP380_REG_FIFO_WATERMARK_LSB:
+	case BMP380_REG_FIFO_WATERMARK_MSB:
+	case BMP380_REG_POWER_CONTROL:
+	case BMP380_REG_INT_CONTROL:
+	case BMP380_REG_IF_CONFIG:
+	case BMP380_REG_ODR:
+	case BMP380_REG_OSR:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool bmp380_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case BMP380_REG_TEMP_XLSB:
+	case BMP380_REG_TEMP_LSB:
+	case BMP380_REG_TEMP_MSB:
+	case BMP380_REG_PRESS_XLSB:
+	case BMP380_REG_PRESS_LSB:
+	case BMP380_REG_PRESS_MSB:
+	case BMP380_REG_SENSOR_TIME_XLSB:
+	case BMP380_REG_SENSOR_TIME_LSB:
+	case BMP380_REG_SENSOR_TIME_MSB:
+	case BMP380_REG_INT_STATUS:
+	case BMP380_REG_FIFO_DATA:
+	case BMP380_REG_STATUS:
+	case BMP380_REG_ERROR:
+	case BMP380_REG_EVENT:
+		return true;
+	default:
+		return false;
+	}
+}
+
 const struct regmap_config bmp280_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
@@ -83,3 +126,15 @@ const struct regmap_config bmp280_regmap_config = {
 	.volatile_reg = bmp280_is_volatile_reg,
 };
 EXPORT_SYMBOL_NS(bmp280_regmap_config, IIO_BMP280);
+
+const struct regmap_config bmp380_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = BMP380_REG_CMD,
+	.cache_type = REGCACHE_RBTREE,
+
+	.writeable_reg = bmp380_is_writeable_reg,
+	.volatile_reg = bmp380_is_volatile_reg,
+};
+EXPORT_SYMBOL_NS(bmp380_regmap_config, IIO_BMP280);
diff --git a/drivers/iio/pressure/bmp280-spi.c b/drivers/iio/pressure/bmp280-spi.c
index 4cfaf3e869b8..011c68e07ebf 100644
--- a/drivers/iio/pressure/bmp280-spi.c
+++ b/drivers/iio/pressure/bmp280-spi.c
@@ -66,6 +66,9 @@ static int bmp280_spi_probe(struct spi_device *spi)
 	case BME280_CHIP_ID:
 		regmap_config = &bmp280_regmap_config;
 		break;
+	case BMP380_CHIP_ID:
+		regmap_config = &bmp380_regmap_config;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -92,6 +95,7 @@ static const struct of_device_id bmp280_of_spi_match[] = {
 	{ .compatible = "bosch,bmp181", },
 	{ .compatible = "bosch,bmp280", },
 	{ .compatible = "bosch,bme280", },
+	{ .compatible = "bosch,bmp380", },
 	{ },
 };
 MODULE_DEVICE_TABLE(of, bmp280_of_spi_match);
@@ -101,6 +105,7 @@ static const struct spi_device_id bmp280_spi_id[] = {
 	{ "bmp181", BMP180_CHIP_ID },
 	{ "bmp280", BMP280_CHIP_ID },
 	{ "bme280", BME280_CHIP_ID },
+	{ "bmp380", BMP380_CHIP_ID },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, bmp280_spi_id);
diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
index c9214a7e5cc6..b546d7727a96 100644
--- a/drivers/iio/pressure/bmp280.h
+++ b/drivers/iio/pressure/bmp280.h
@@ -3,6 +3,105 @@
 #include <linux/device.h>
 #include <linux/regmap.h>
 
+/* BMP380 specific registers */
+#define BMP380_REG_CMD			0x7E
+#define BMP380_REG_CONFIG		0x1F
+#define BMP380_REG_ODR			0x1D
+#define BMP380_REG_OSR			0x1C
+#define BMP380_REG_POWER_CONTROL	0x1B
+#define BMP380_REG_IF_CONFIG		0x1A
+#define BMP380_REG_INT_CONTROL		0x19
+#define BMP380_REG_INT_STATUS		0x11
+#define BMP380_REG_EVENT		0x10
+#define BMP380_REG_STATUS		0x03
+#define BMP380_REG_ERROR		0x02
+#define BMP380_REG_ID			0x00
+
+#define BMP380_REG_FIFO_CONFIG_1	0x18
+#define BMP380_REG_FIFO_CONFIG_2	0x17
+#define BMP380_REG_FIFO_WATERMARK_MSB	0x16
+#define BMP380_REG_FIFO_WATERMARK_LSB	0x15
+#define BMP380_REG_FIFO_DATA		0x14
+#define BMP380_REG_FIFO_LENGTH_MSB	0x13
+#define BMP380_REG_FIFO_LENGTH_LSB	0x12
+
+#define BMP380_REG_SENSOR_TIME_MSB	0x0E
+#define BMP380_REG_SENSOR_TIME_LSB	0x0D
+#define BMP380_REG_SENSOR_TIME_XLSB	0x0C
+
+#define BMP380_REG_TEMP_MSB		0x09
+#define BMP380_REG_TEMP_LSB		0x08
+#define BMP380_REG_TEMP_XLSB		0x07
+
+#define BMP380_REG_PRESS_MSB		0x06
+#define BMP380_REG_PRESS_LSB		0x05
+#define BMP380_REG_PRESS_XLSB		0x04
+
+#define BMP380_REG_CALIB_TEMP_START	0x31
+#define BMP380_CALIB_REG_COUNT		21
+
+#define BMP380_FILTER_MASK		GENMASK(3, 1)
+#define BMP380_FILTER_OFF		0
+#define BMP380_FILTER_1X		1
+#define BMP380_FILTER_3X		2
+#define BMP380_FILTER_7X		3
+#define BMP380_FILTER_15X		4
+#define BMP380_FILTER_31X		5
+#define BMP380_FILTER_63X		6
+#define BMP380_FILTER_127X		7
+
+#define BMP380_OSRS_TEMP_MASK		GENMASK(5, 3)
+#define BMP380_OSRS_PRESS_MASK		GENMASK(2, 0)
+
+#define BMP380_ODRS_MASK		GENMASK(4, 0)
+#define BMP380_ODRS_200HZ		0x00
+#define BMP380_ODRS_100HZ		0x01
+#define BMP380_ODRS_50HZ		0x02
+#define BMP380_ODRS_25HZ		0x03
+#define BMP380_ODRS_12_5HZ		0x04
+#define BMP380_ODRS_6_25HZ		0x05
+#define BMP380_ODRS_3_1HZ		0x06
+#define BMP380_ODRS_1_5HZ		0x07
+#define BMP380_ODRS_0_78HZ		0x08
+#define BMP380_ODRS_0_39HZ		0x09
+#define BMP380_ODRS_0_2HZ		0x0A
+#define BMP380_ODRS_0_1HZ		0x0B
+#define BMP380_ODRS_0_05HZ		0x0C
+#define BMP380_ODRS_0_02HZ		0x0D
+#define BMP380_ODRS_0_01HZ		0x0E
+#define BMP380_ODRS_0_006HZ		0x0F
+#define BMP380_ODRS_0_003HZ		0x10
+#define BMP380_ODRS_0_0015HZ		0x11
+
+#define BMP380_CTRL_SENSORS_MASK	GENMASK(1, 0)
+#define BMP380_CTRL_SENSORS_PRESS_EN	BIT(0)
+#define BMP380_CTRL_SENSORS_TEMP_EN	BIT(1)
+#define BMP380_MODE_MASK		GENMASK(5, 4)
+#define BMP380_MODE_SLEEP		0
+#define BMP380_MODE_FORCED		1
+#define BMP380_MODE_NORMAL		3
+
+#define BMP380_MIN_TEMP			-4000
+#define BMP380_MAX_TEMP			8500
+#define BMP380_MIN_PRES			3000000
+#define BMP380_MAX_PRES			12500000
+
+#define BMP380_CMD_NOOP			0x00
+#define BMP380_CMD_EXTMODE_EN_MID	0x34
+#define BMP380_CMD_FIFO_FLUSH		0xB0
+#define BMP380_CMD_SOFT_RESET		0xB6
+
+#define BMP380_STATUS_CMD_RDY_MASK	BIT(4)
+#define BMP380_STATUS_DRDY_PRESS_MASK	BIT(5)
+#define BMP380_STATUS_DRDY_TEMP_MASK	BIT(6)
+
+#define BMP380_ERR_FATAL_MASK		BIT(0)
+#define BMP380_ERR_CMD_MASK		BIT(1)
+#define BMP380_ERR_CONF_MASK		BIT(2)
+
+#define BMP380_TEMP_SKIPPED		0x800000
+#define BMP380_PRESS_SKIPPED		0x800000
+
 /* BMP280 specific registers */
 #define BMP280_REG_HUMIDITY_LSB		0xFE
 #define BMP280_REG_HUMIDITY_MSB		0xFD
@@ -99,6 +198,7 @@
 #define BMP280_REG_RESET		0xE0
 #define BMP280_REG_ID			0xD0
 
+#define BMP380_CHIP_ID			0x50
 #define BMP180_CHIP_ID			0x55
 #define BMP280_CHIP_ID			0x58
 #define BME280_CHIP_ID			0x60
@@ -112,6 +212,7 @@
 /* Regmap configurations */
 extern const struct regmap_config bmp180_regmap_config;
 extern const struct regmap_config bmp280_regmap_config;
+extern const struct regmap_config bmp380_regmap_config;
 
 /* Probe called from different transports */
 int bmp280_common_probe(struct device *dev,
-- 
2.37.3

Re: [PATCH v6 7/9] iio: pressure: bmp280: Add support for BMP380 sensor family

[Andy Shevchenko]

On Tue, Sep 13, 2022 at 01:52:13AM +0200, Angel Iglesias wrote:
> Adds compatibility with the new generation of this sensor, the BMP380.
> 
> Includes basic sensor initialization to do pressure and temp
> measurements and allows tuning oversampling settings for each channel.
> 
> The compensation algorithms are adapted from the device datasheet and
> the repository https://github.com/BoschSensortec/BMP3-Sensor-API.

...

>   * 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
> + * https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bmp388-ds001.pdf
>   */

Shouldn't it be based on your patch to fix the links?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v6 7/9] iio: pressure: bmp280: Add support for BMP380 sensor family

[Angel Iglesias]

On Tue, 2022-09-13 at 19:46 +0300, Andy Shevchenko wrote:
> On Tue, Sep 13, 2022 at 01:52:13AM +0200, Angel Iglesias wrote:
> > Adds compatibility with the new generation of this sensor, the BMP380.
> > 
> > Includes basic sensor initialization to do pressure and temp
> > measurements and allows tuning oversampling settings for each channel.
> > 
> > The compensation algorithms are adapted from the device datasheet and
> > the repository https://github.com/BoschSensortec/BMP3-Sensor-API.
> 
> ...
> 
> >   *
> > 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
> > + *
> > https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bmp388-ds001.pdf
> >   */
> 
> Shouldn't it be based on your patch to fix the links?
> 
I thought of adding the patch fixing the links as a prerequisite commit, but in
the end decided to keep the patchsets independent to avoid codependencies.

Kind regards,
Angel

Re: [PATCH v6 7/9] iio: pressure: bmp280: Add support for BMP380 sensor family

[Andy Shevchenko]

On Tue, Sep 13, 2022 at 11:19:37PM +0200, Angel Iglesias wrote:
> On Tue, 2022-09-13 at 19:46 +0300, Andy Shevchenko wrote:
> > On Tue, Sep 13, 2022 at 01:52:13AM +0200, Angel Iglesias wrote:

...

> > >   *
> > > 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
> > > + *
> > > https://www.bosch-sensortec.com/media/boschsensortec/downloads/datasheets/bst-bmp388-ds001.pdf
> > >   */
> > 
> > Shouldn't it be based on your patch to fix the links?
> > 
> I thought of adding the patch fixing the links as a prerequisite commit, but in
> the end decided to keep the patchsets independent to avoid codependencies.

I see, then whatever Jonathan decides.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v6 7/9] iio: pressure: bmp280: Add support for BMP380 sensor family

[Jonathan Cameron]

On Tue, 13 Sep 2022 01:52:13 +0200
Angel Iglesias <ang.iglesiasg@gmail.com> wrote:

> Adds compatibility with the new generation of this sensor, the BMP380.
> 
> Includes basic sensor initialization to do pressure and temp
> measurements and allows tuning oversampling settings for each channel.
> 
> The compensation algorithms are adapted from the device datasheet and
> the repository https://github.com/BoschSensortec/BMP3-Sensor-API.
> 
> Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
There is one place (around the reset handing) in here where I
suspect we'll end up revisiting it because the matching by
device ID is not particularly extensible to new devices.

Anyhow, can handle that at the time.

I had to hand apply parts of this because of the clash Andy
raised.  As a general rule it's better to keep one linear
flow of patches unless they are on well separate parts of
a driver.  Saves me effort :)  Here it was just one line to
cut and paste, but you still get to now check I didn't mess
that up ;)

Applied - please check result in testing branch of iio.git.

Note I plan to rebase that branch after the first pull request
is accepted as I have some dependencies blocking other
patches and a fast forward rebase is the easiest way to deal
with those cleanly.

Jonathan

Re: [PATCH v6 7/9] iio: pressure: bmp280: Add support for BMP380 sensor family

[Angel Iglesias]

On Sat, 2022-09-17 at 14:25 +0100, Jonathan Cameron wrote:
> On Tue, 13 Sep 2022 01:52:13 +0200
> Angel Iglesias <ang.iglesiasg@gmail.com> wrote:
> 
> > Adds compatibility with the new generation of this sensor, the BMP380.
> > 
> > Includes basic sensor initialization to do pressure and temp
> > measurements and allows tuning oversampling settings for each channel.
> > 
> > The compensation algorithms are adapted from the device datasheet and
> > the repository https://github.com/BoschSensortec/BMP3-Sensor-API.
> > 
> > Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
> There is one place (around the reset handing) in here where I
> suspect we'll end up revisiting it because the matching by
> device ID is not particularly extensible to new devices.

Yeah, after the first time you raised that concern I've been thinking that maybe
it would be better to add a new "init" or "preinit" callback executing first
boot tasks for a sensor, such as this reset. Please, let me know how I can help
with this matter. On the other hand, I'll have the BMP390 and BMP581 on my hands
in a week or two. The BMP390 is almost the same regmap and operations as the
BMP380, so I think it will be an easy addition. The BMP581 is a new beast that
brings in lots of changes, but still has a good bunch of similarities.

> Anyhow, can handle that at the time.
> 
> I had to hand apply parts of this because of the clash Andy
> raised.  As a general rule it's better to keep one linear
> flow of patches unless they are on well separate parts of
> a driver.  Saves me effort :)  Here it was just one line to
> cut and paste, but you still get to now check I didn't mess
> that up ;)

Sorry about that. Thanks to you and Andy for the extra patience with my messy
patches.

> Applied - please check result in testing branch of iio.git.
> 
> Note I plan to rebase that branch after the first pull request
> is accepted as I have some dependencies blocking other
> patches and a fast forward rebase is the easiest way to deal
> with those cleanly.
> 
> Jonathan

With kind regards,
Angel

Re: [PATCH v6 7/9] iio: pressure: bmp280: Add support for BMP380 sensor family

[Jonathan Cameron]

On Sun, 18 Sep 2022 12:06:45 +0200
Angel Iglesias <ang.iglesiasg@gmail.com> wrote:

> On Sat, 2022-09-17 at 14:25 +0100, Jonathan Cameron wrote:
> > On Tue, 13 Sep 2022 01:52:13 +0200
> > Angel Iglesias <ang.iglesiasg@gmail.com> wrote:
> >   
> > > Adds compatibility with the new generation of this sensor, the BMP380.
> > > 
> > > Includes basic sensor initialization to do pressure and temp
> > > measurements and allows tuning oversampling settings for each channel.
> > > 
> > > The compensation algorithms are adapted from the device datasheet and
> > > the repository https://github.com/BoschSensortec/BMP3-Sensor-API.
> > > 
> > > Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>  
> > There is one place (around the reset handing) in here where I
> > suspect we'll end up revisiting it because the matching by
> > device ID is not particularly extensible to new devices.  
> 
> Yeah, after the first time you raised that concern I've been thinking that maybe
> it would be better to add a new "init" or "preinit" callback executing first
> boot tasks for a sensor, such as this reset. Please, let me know how I can help
> with this matter. On the other hand, I'll have the BMP390 and BMP581 on my hands
> in a week or two. The BMP390 is almost the same regmap and operations as the
> BMP380, so I think it will be an easy addition. The BMP581 is a new beast that
> brings in lots of changes, but still has a good bunch of similarities.

Agreed, an .init()/.preinit() callback might make sense.

Given you are planning to look at new parts, perhaps wait until you
have a series adding one of those rather than creating churn in the
driver before that point.  Perhaps the BMP581 will require changes
in this area of the driver anyway and we don't want to end up
changing it twice!

Thanks,

Jonathan

[PATCH v6 8/9] dt-bindings: iio: pressure: bmp085: Add BMP380 compatible string

[Angel Iglesias]

Add bosch,bmp380 compatible string for the new family of sensors.
This family includes the BMP380, BMP384 and BMP388. The register map
in this family changes substantially and introduces new features
but core concepts and operations carryover from the previous iterations

Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 Documentation/devicetree/bindings/iio/pressure/bmp085.yaml | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/iio/pressure/bmp085.yaml b/Documentation/devicetree/bindings/iio/pressure/bmp085.yaml
index 49257f9251e8..72cd2c2d3f17 100644
--- a/Documentation/devicetree/bindings/iio/pressure/bmp085.yaml
+++ b/Documentation/devicetree/bindings/iio/pressure/bmp085.yaml
@@ -4,7 +4,7 @@
 $id: http://devicetree.org/schemas/iio/pressure/bmp085.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
-title: BMP085/BMP180/BMP280/BME280 pressure iio sensors
+title: BMP085/BMP180/BMP280/BME280/BMP380 pressure iio sensors
 
 maintainers:
   - Andreas Klinger <ak@it-klinger.de>
@@ -16,6 +16,7 @@ description: |
     https://www.bosch-sensortec.com/bst/products/all_products/bmp180
     https://www.bosch-sensortec.com/bst/products/all_products/bmp280
     https://www.bosch-sensortec.com/bst/products/all_products/bme280
+    https://www.bosch-sensortec.com/bst/products/all_products/bmp380
 
 properties:
   compatible:
@@ -24,6 +25,7 @@ properties:
       - bosch,bmp180
       - bosch,bmp280
       - bosch,bme280
+      - bosch,bmp380
 
   reg:
     maxItems: 1
-- 
2.37.3

[PATCH v6 9/9] iio: pressure: bmp280: Add more tunable config parameters for BMP380

[Angel Iglesias]

Allows sampling frequency and IIR filter coefficients configuration
using sysfs ABI.

The IIR filter coefficient is configurable using the sysfs attribute
"filter_low_pass_3db_frequency".

Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
---
 drivers/iio/pressure/bmp280-core.c | 247 +++++++++++++++++++++++++++--
 drivers/iio/pressure/bmp280.h      |  18 ---
 2 files changed, 238 insertions(+), 27 deletions(-)

diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index 19ac93bb1b83..743bc5a527f8 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -103,6 +103,27 @@ static const char *const bmp280_supply_names[] = {
 
 #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;
@@ -122,6 +143,17 @@ struct bmp280_data {
 	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
@@ -149,6 +181,7 @@ struct bmp280_data {
 struct bmp280_chip_info {
 	unsigned int id_reg;
 
+	const struct iio_chan_spec *channels;
 	int num_channels;
 	unsigned int start_up_time;
 
@@ -164,6 +197,14 @@ struct bmp280_chip_info {
 	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 *);
@@ -214,6 +255,30 @@ static const struct iio_chan_spec bmp280_channels[] = {
 	},
 };
 
+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;
@@ -544,6 +609,25 @@ static int bmp280_read_raw(struct iio_dev *indio_dev,
 			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;
@@ -561,13 +645,21 @@ static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data,
 {
 	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);
 
-			return data->chip_info->chip_config(data);
+			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;
@@ -578,13 +670,21 @@ static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data,
 {
 	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);
 
-			return data->chip_info->chip_config(data);
+			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;
@@ -595,13 +695,71 @@ static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data,
 {
 	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);
 
-			return data->chip_info->chip_config(data);
+			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;
@@ -614,6 +772,12 @@ static int bmp280_write_raw(struct iio_dev *indio_dev,
 	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);
@@ -636,6 +800,22 @@ static int bmp280_write_raw(struct iio_dev *indio_dev,
 		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;
 	}
@@ -666,6 +846,17 @@ static int bmp280_read_avail(struct iio_dev *indio_dev,
 		}
 		*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;
 	}
@@ -711,6 +902,7 @@ 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,
@@ -758,6 +950,7 @@ static int bme280_chip_config(struct bmp280_data *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,
@@ -997,6 +1190,27 @@ static int bmp380_read_calib(struct bmp280_data *data)
 	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;
@@ -1030,21 +1244,23 @@ static int bmp380_chip_config(struct bmp280_data *data)
 	change = change || aux;
 
 	/* Configure output data rate */
-	ret = regmap_update_bits(data->regmap, BMP380_REG_ODR,
-				 BMP380_ODRS_MASK, BMP380_ODRS_50HZ);
+	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(data->regmap, BMP380_REG_CONFIG,
-				 BMP380_FILTER_MASK,
-				 FIELD_PREP(BMP380_FILTER_MASK, BMP380_FILTER_3X));
+	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) {
 		/*
@@ -1095,10 +1311,12 @@ static int bmp380_chip_config(struct bmp280_data *data)
 }
 
 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,
@@ -1109,6 +1327,14 @@ static const struct bmp280_chip_info bmp380_chip_info = {
 	.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,
@@ -1350,6 +1576,7 @@ 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,
@@ -1448,7 +1675,6 @@ int bmp280_common_probe(struct device *dev,
 	data->dev = dev;
 
 	indio_dev->name = name;
-	indio_dev->channels = bmp280_channels;
 	indio_dev->info = &bmp280_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
@@ -1471,10 +1697,13 @@ int bmp280_common_probe(struct device *dev,
 	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 */
diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
index b546d7727a96..c791325c7416 100644
--- a/drivers/iio/pressure/bmp280.h
+++ b/drivers/iio/pressure/bmp280.h
@@ -54,24 +54,6 @@
 #define BMP380_OSRS_PRESS_MASK		GENMASK(2, 0)
 
 #define BMP380_ODRS_MASK		GENMASK(4, 0)
-#define BMP380_ODRS_200HZ		0x00
-#define BMP380_ODRS_100HZ		0x01
-#define BMP380_ODRS_50HZ		0x02
-#define BMP380_ODRS_25HZ		0x03
-#define BMP380_ODRS_12_5HZ		0x04
-#define BMP380_ODRS_6_25HZ		0x05
-#define BMP380_ODRS_3_1HZ		0x06
-#define BMP380_ODRS_1_5HZ		0x07
-#define BMP380_ODRS_0_78HZ		0x08
-#define BMP380_ODRS_0_39HZ		0x09
-#define BMP380_ODRS_0_2HZ		0x0A
-#define BMP380_ODRS_0_1HZ		0x0B
-#define BMP380_ODRS_0_05HZ		0x0C
-#define BMP380_ODRS_0_02HZ		0x0D
-#define BMP380_ODRS_0_01HZ		0x0E
-#define BMP380_ODRS_0_006HZ		0x0F
-#define BMP380_ODRS_0_003HZ		0x10
-#define BMP380_ODRS_0_0015HZ		0x11
 
 #define BMP380_CTRL_SENSORS_MASK	GENMASK(1, 0)
 #define BMP380_CTRL_SENSORS_PRESS_EN	BIT(0)
-- 
2.37.3

Re: [PATCH v6 9/9] iio: pressure: bmp280: Add more tunable config parameters for BMP380

[Jonathan Cameron]

On Tue, 13 Sep 2022 01:54:42 +0200
Angel Iglesias <ang.iglesiasg@gmail.com> wrote:

> Allows sampling frequency and IIR filter coefficients configuration
> using sysfs ABI.
> 
> The IIR filter coefficient is configurable using the sysfs attribute
> "filter_low_pass_3db_frequency".
> 
> Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>

Applied to the togreg branch of iio.git and initially pushed out
as testing for the autobuilders to poke at it.

Thanks,

Jonathan