iio: pressure: bmp280: split driver in logical parts

This splits the BMP280 driver in three logical parts: the core driver
bmp280-core that only operated on a struct device * and a struct regmap *,
the regmap driver bmp280-regmap that can be shared between I2C and other
transports and the I2C module driver bmp280-i2c.

Cleverly bake all functionality into a single object bmp280.o so that
we still get the same module binary built for the device in the end,
without any fuzz exporting symbols to the left and right.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/pressure/Makefile

@@ -4,6 +4,7 @@
 
 # When adding new entries keep the list in alphabetical order
 obj-$(CONFIG_BMP280) += bmp280.o
+bmp280-objs := bmp280-core.o bmp280-regmap.o bmp280-i2c.o
 obj-$(CONFIG_HID_SENSOR_PRESS)   += hid-sensor-press.o
 obj-$(CONFIG_HP03) += hp03.o
 obj-$(CONFIG_MPL115) += mpl115.o

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

@@ -15,10 +15,7 @@
 
 #define pr_fmt(fmt) "bmp280: " fmt
 
-#include <linux/module.h>
-#include <linux/i2c.h>
-#include <linux/acpi.h>
-#include <linux/of.h>
+#include <linux/device.h>
 #include <linux/regmap.h>
 #include <linux/delay.h>
 #include <linux/iio/iio.h>
@@ -26,102 +23,10 @@
 #include <linux/gpio/consumer.h>
 #include <linux/regulator/consumer.h>
 
-/* BMP280 specific registers */
-#define BMP280_REG_HUMIDITY_LSB		0xFE
-#define BMP280_REG_HUMIDITY_MSB		0xFD
-#define BMP280_REG_TEMP_XLSB		0xFC
-#define BMP280_REG_TEMP_LSB		0xFB
-#define BMP280_REG_TEMP_MSB		0xFA
-#define BMP280_REG_PRESS_XLSB		0xF9
-#define BMP280_REG_PRESS_LSB		0xF8
-#define BMP280_REG_PRESS_MSB		0xF7
-
-#define BMP280_REG_CONFIG		0xF5
-#define BMP280_REG_CTRL_MEAS		0xF4
-#define BMP280_REG_STATUS		0xF3
-#define BMP280_REG_CTRL_HUMIDITY	0xF2
-
-/* Due to non linear mapping, and data sizes we can't do a bulk read */
-#define BMP280_REG_COMP_H1		0xA1
-#define BMP280_REG_COMP_H2		0xE1
-#define BMP280_REG_COMP_H3		0xE3
-#define BMP280_REG_COMP_H4		0xE4
-#define BMP280_REG_COMP_H5		0xE5
-#define BMP280_REG_COMP_H6		0xE7
-
-#define BMP280_REG_COMP_TEMP_START	0x88
-#define BMP280_COMP_TEMP_REG_COUNT	6
-
-#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_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_OSRS_HUMIDITY_MASK	(BIT(2) | BIT(1) | BIT(0))
-#define BMP280_OSRS_HUMIDITIY_X(osrs_h)	((osrs_h) << 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_TEMP_MASK		(BIT(7) | BIT(6) | BIT(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_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_MODE_SLEEP		0
-#define BMP280_MODE_FORCED		BIT(0)
-#define BMP280_MODE_NORMAL		(BIT(1) | BIT(0))
-
-/* BMP180 specific registers */
-#define BMP180_REG_OUT_XLSB		0xF8
-#define BMP180_REG_OUT_LSB		0xF7
-#define BMP180_REG_OUT_MSB		0xF6
-
-#define BMP180_REG_CALIB_START		0xAA
-#define BMP180_REG_CALIB_COUNT		22
-
-#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)
-
-/* BMP180 and BMP280 common registers */
-#define BMP280_REG_CTRL_MEAS		0xF4
-#define BMP280_REG_RESET		0xE0
-#define BMP280_REG_ID			0xD0
-
-#define BMP180_CHIP_ID			0x55
-#define BMP280_CHIP_ID			0x58
-#define BME280_CHIP_ID			0x60
-#define BMP280_SOFT_RESET_VAL		0xB6
+#include "bmp280.h"
 
 struct bmp280_data {
-	struct i2c_client *client;
+	struct device *dev;
 	struct mutex lock;
 	struct regmap *regmap;
 	const struct bmp280_chip_info *chip_info;
@@ -142,8 +47,6 @@ struct bmp280_data {
 };
 
 struct bmp280_chip_info {
-	const struct regmap_config *regmap_config;
-
 	const int *oversampling_temp_avail;
 	int num_oversampling_temp_avail;
 
@@ -184,48 +87,6 @@ static const struct iio_chan_spec bmp280_channels[] = {
 	},
 };
 
-static bool bmp280_is_writeable_reg(struct device *dev, unsigned int reg)
-{
-	switch (reg) {
-	case BMP280_REG_CONFIG:
-	case BMP280_REG_CTRL_HUMIDITY:
-	case BMP280_REG_CTRL_MEAS:
-	case BMP280_REG_RESET:
-		return true;
-	default:
-		return false;
-	};
-}
-
-static bool bmp280_is_volatile_reg(struct device *dev, unsigned int reg)
-{
-	switch (reg) {
-	case BMP280_REG_HUMIDITY_LSB:
-	case BMP280_REG_HUMIDITY_MSB:
-	case BMP280_REG_TEMP_XLSB:
-	case BMP280_REG_TEMP_LSB:
-	case BMP280_REG_TEMP_MSB:
-	case BMP280_REG_PRESS_XLSB:
-	case BMP280_REG_PRESS_LSB:
-	case BMP280_REG_PRESS_MSB:
-	case BMP280_REG_STATUS:
-		return true;
-	default:
-		return false;
-	}
-}
-
-static const struct regmap_config bmp280_regmap_config = {
-	.reg_bits = 8,
-	.val_bits = 8,
-
-	.max_register = BMP280_REG_HUMIDITY_LSB,
-	.cache_type = REGCACHE_RBTREE,
-
-	.writeable_reg = bmp280_is_writeable_reg,
-	.volatile_reg = bmp280_is_volatile_reg,
-};
-
 /*
  * Returns humidity in percent, resolution is 0.01 percent. Output value of
  * "47445" represents 47445/1024 = 46.333 %RH.
@@ -236,7 +97,7 @@ static const struct regmap_config bmp280_regmap_config = {
 static u32 bmp280_compensate_humidity(struct bmp280_data *data,
 				      s32 adc_humidity)
 {
-	struct device *dev = &data->client->dev;
+	struct device *dev = data->dev;
 	unsigned int H1, H3, tmp;
 	int H2, H4, H5, H6, ret, var;
 
@@ -307,7 +168,7 @@ static s32 bmp280_compensate_temp(struct bmp280_data *data,
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_TEMP_START,
 			       buf, BMP280_COMP_TEMP_REG_COUNT);
 	if (ret < 0) {
-		dev_err(&data->client->dev,
+		dev_err(data->dev,
 			"failed to read temperature calibration parameters\n");
 		return ret;
 	}
@@ -347,7 +208,7 @@ static u32 bmp280_compensate_press(struct bmp280_data *data,
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_COMP_PRESS_START,
 			       buf, BMP280_COMP_PRESS_REG_COUNT);
 	if (ret < 0) {
-		dev_err(&data->client->dev,
+		dev_err(data->dev,
 			"failed to read pressure calibration parameters\n");
 		return ret;
 	}
@@ -382,7 +243,7 @@ static int bmp280_read_temp(struct bmp280_data *data,
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_TEMP_MSB,
 			       (u8 *) &tmp, 3);
 	if (ret < 0) {
-		dev_err(&data->client->dev, "failed to read temperature\n");
+		dev_err(data->dev, "failed to read temperature\n");
 		return ret;
 	}
 
@@ -417,7 +278,7 @@ static int bmp280_read_press(struct bmp280_data *data,
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_PRESS_MSB,
 			       (u8 *) &tmp, 3);
 	if (ret < 0) {
-		dev_err(&data->client->dev, "failed to read pressure\n");
+		dev_err(data->dev, "failed to read pressure\n");
 		return ret;
 	}
 
@@ -445,7 +306,7 @@ static int bmp280_read_humid(struct bmp280_data *data, int *val, int *val2)
 	ret = regmap_bulk_read(data->regmap, BMP280_REG_HUMIDITY_MSB,
 			       (u8 *) &tmp, 2);
 	if (ret < 0) {
-		dev_err(&data->client->dev, "failed to read humidity\n");
+		dev_err(data->dev, "failed to read humidity\n");
 		return ret;
 	}
 
@@ -663,7 +524,7 @@ static int bmp280_chip_config(struct bmp280_data *data)
 				 BMP280_MODE_MASK,
 				 osrs | BMP280_MODE_NORMAL);
 	if (ret < 0) {
-		dev_err(&data->client->dev,
+		dev_err(data->dev,
 			"failed to write ctrl_meas register\n");
 		return ret;
 	}
@@ -672,7 +533,7 @@ static int bmp280_chip_config(struct bmp280_data *data)
 				 BMP280_FILTER_MASK,
 				 BMP280_FILTER_4X);
 	if (ret < 0) {
-		dev_err(&data->client->dev,
+		dev_err(data->dev,
 			"failed to write config register\n");
 		return ret;
 	}
@@ -683,8 +544,6 @@ 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 = {
-	.regmap_config = &bmp280_regmap_config,
-
 	.oversampling_temp_avail = bmp280_oversampling_avail,
 	.num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
 
@@ -709,8 +568,6 @@ static int bme280_chip_config(struct bmp280_data *data)
 }
 
 static const struct bmp280_chip_info bme280_chip_info = {
-	.regmap_config = &bmp280_regmap_config,
-
 	.oversampling_temp_avail = bmp280_oversampling_avail,
 	.num_oversampling_temp_avail = ARRAY_SIZE(bmp280_oversampling_avail),
 
@@ -726,42 +583,6 @@ static const struct bmp280_chip_info bme280_chip_info = {
 	.read_humid = bmp280_read_humid,
 };
 
-
-static bool bmp180_is_writeable_reg(struct device *dev, unsigned int reg)
-{
-	switch (reg) {
-	case BMP280_REG_CTRL_MEAS:
-	case BMP280_REG_RESET:
-		return true;
-	default:
-		return false;
-	};
-}
-
-static bool bmp180_is_volatile_reg(struct device *dev, unsigned int reg)
-{
-	switch (reg) {
-	case BMP180_REG_OUT_XLSB:
-	case BMP180_REG_OUT_LSB:
-	case BMP180_REG_OUT_MSB:
-	case BMP280_REG_CTRL_MEAS:
-		return true;
-	default:
-		return false;
-	}
-}
-
-static const struct regmap_config bmp180_regmap_config = {
-	.reg_bits = 8,
-	.val_bits = 8,
-
-	.max_register = BMP180_REG_OUT_XLSB,
-	.cache_type = REGCACHE_RBTREE,
-
-	.writeable_reg = bmp180_is_writeable_reg,
-	.volatile_reg = bmp180_is_volatile_reg,
-};
-
 static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
 {
 	int ret;
@@ -877,7 +698,7 @@ static s32 bmp180_compensate_temp(struct bmp280_data *data, s32 adc_temp)
 
 	ret = bmp180_read_calib(data, &calib);
 	if (ret < 0) {
-		dev_err(&data->client->dev,
+		dev_err(data->dev,
 			"failed to read calibration coefficients\n");
 		return ret;
 	}
@@ -947,7 +768,7 @@ static u32 bmp180_compensate_press(struct bmp280_data *data, s32 adc_press)
 
 	ret = bmp180_read_calib(data, &calib);
 	if (ret < 0) {
-		dev_err(&data->client->dev,
+		dev_err(data->dev,
 			"failed to read calibration coefficients\n");
 		return ret;
 	}
@@ -1007,8 +828,6 @@ 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 = {
-	.regmap_config = &bmp180_regmap_config,
-
 	.oversampling_temp_avail = bmp180_oversampling_temp_avail,
 	.num_oversampling_temp_avail =
 		ARRAY_SIZE(bmp180_oversampling_temp_avail),
@@ -1022,8 +841,10 @@ static const struct bmp280_chip_info bmp180_chip_info = {
 	.read_press = bmp180_read_press,
 };
 
-static int bmp280_probe(struct i2c_client *client,
-			const struct i2c_device_id *id)
+int bmp280_common_probe(struct device *dev,
+			struct regmap *regmap,
+			unsigned int chip,
+			const char *name)
 {
 	int ret;
 	struct iio_dev *indio_dev;
@@ -1031,21 +852,21 @@ static int bmp280_probe(struct i2c_client *client,
 	unsigned int chip_id;
 	struct gpio_desc *gpiod;
 
-	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
 	if (!indio_dev)
 		return -ENOMEM;
 
 	data = iio_priv(indio_dev);
 	mutex_init(&data->lock);
-	data->client = client;
+	data->dev = dev;
 
-	indio_dev->dev.parent = &client->dev;
-	indio_dev->name = id->name;
+	indio_dev->dev.parent = dev;
+	indio_dev->name = name;
 	indio_dev->channels = bmp280_channels;
 	indio_dev->info = &bmp280_info;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
-	switch (id->driver_data) {
+	switch (chip) {
 	case BMP180_CHIP_ID:
 		indio_dev->num_channels = 2;
 		data->chip_info = &bmp180_chip_info;
@@ -1073,52 +894,45 @@ static int bmp280_probe(struct i2c_client *client,
 	}
 
 	/* Bring up regulators */
-	data->vddd = devm_regulator_get(&client->dev, "vddd");
+	data->vddd = devm_regulator_get(dev, "vddd");
 	if (IS_ERR(data->vddd)) {
-		dev_err(&client->dev, "failed to get VDDD regulator\n");
+		dev_err(dev, "failed to get VDDD regulator\n");
 		return PTR_ERR(data->vddd);
 	}
 	ret = regulator_enable(data->vddd);
 	if (ret) {
-		dev_err(&client->dev, "failed to enable VDDD regulator\n");
+		dev_err(dev, "failed to enable VDDD regulator\n");
 		return ret;
 	}
-	data->vdda = devm_regulator_get(&client->dev, "vdda");
+	data->vdda = devm_regulator_get(dev, "vdda");
 	if (IS_ERR(data->vdda)) {
-		dev_err(&client->dev, "failed to get VDDA regulator\n");
+		dev_err(dev, "failed to get VDDA regulator\n");
 		ret = PTR_ERR(data->vddd);
 		goto out_disable_vddd;
 	}
 	ret = regulator_enable(data->vdda);
 	if (ret) {
-		dev_err(&client->dev, "failed to enable VDDA regulator\n");
+		dev_err(dev, "failed to enable VDDA regulator\n");
 		goto out_disable_vddd;
 	}
 	/* Wait to make sure we started up properly */
 	mdelay(data->start_up_time);
 
 	/* Bring chip out of reset if there is an assigned GPIO line */
-	gpiod = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH);
+	gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
 	/* Deassert the signal */
 	if (!IS_ERR(gpiod)) {
-		dev_info(&client->dev, "release reset\n");
+		dev_info(dev, "release reset\n");
 		gpiod_set_value(gpiod, 0);
 	}
 
-	data->regmap = devm_regmap_init_i2c(client,
-					data->chip_info->regmap_config);
-	if (IS_ERR(data->regmap)) {
-		dev_err(&client->dev, "failed to allocate register map\n");
-		ret = PTR_ERR(data->regmap);
-		goto out_disable_vdda;
-	}
-
-	ret = regmap_read(data->regmap, BMP280_REG_ID, &chip_id);
+	data->regmap = regmap;
+	ret = regmap_read(regmap, BMP280_REG_ID, &chip_id);
 	if (ret < 0)
-		return ret;
-	if (chip_id != id->driver_data) {
-		dev_err(&client->dev, "bad chip id.  expected %lx got %x\n",
-			id->driver_data, chip_id);
+		goto out_disable_vdda;
+	if (chip_id != chip) {
+		dev_err(dev, "bad chip id: expected %x got %x\n",
+			chip, chip_id);
 		ret = -EINVAL;
 		goto out_disable_vdda;
 	}
@@ -1127,7 +941,7 @@ static int bmp280_probe(struct i2c_client *client,
 	if (ret < 0)
 		goto out_disable_vdda;
 
-	i2c_set_clientdata(client, indio_dev);
+	dev_set_drvdata(dev, indio_dev);
 
 	ret = iio_device_register(indio_dev);
 	if (ret)
@@ -1142,9 +956,9 @@ out_disable_vddd:
 	return ret;
 }
 
-static int bmp280_remove(struct i2c_client *client)
+int bmp280_common_remove(struct device *dev)
 {
-	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct bmp280_data *data = iio_priv(indio_dev);
 
 	iio_device_unregister(indio_dev);
@@ -1152,50 +966,3 @@ static int bmp280_remove(struct i2c_client *client)
 	regulator_disable(data->vddd);
 	return 0;
 }
-
-static const struct acpi_device_id bmp280_acpi_match[] = {
-	{"BMP0280", BMP280_CHIP_ID },
-	{"BMP0180", BMP180_CHIP_ID },
-	{"BMP0085", BMP180_CHIP_ID },
-	{"BME0280", BME280_CHIP_ID },
-	{ },
-};
-MODULE_DEVICE_TABLE(acpi, bmp280_acpi_match);
-
-#ifdef CONFIG_OF
-static const struct of_device_id bmp280_of_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 },
-	{ },
-};
-MODULE_DEVICE_TABLE(of, bmp280_of_match);
-#else
-#define bmp280_of_match NULL
-#endif
-
-static const struct i2c_device_id bmp280_id[] = {
-	{"bmp280", BMP280_CHIP_ID },
-	{"bmp180", BMP180_CHIP_ID },
-	{"bmp085", BMP180_CHIP_ID },
-	{"bme280", BME280_CHIP_ID },
-	{ },
-};
-MODULE_DEVICE_TABLE(i2c, bmp280_id);
-
-static struct i2c_driver bmp280_driver = {
-	.driver = {
-		.name	= "bmp280",
-		.acpi_match_table = ACPI_PTR(bmp280_acpi_match),
-		.of_match_table = of_match_ptr(bmp280_of_match),
-	},
-	.probe		= bmp280_probe,
-	.remove		= bmp280_remove,
-	.id_table	= bmp280_id,
-};
-module_i2c_driver(bmp280_driver);
-
-MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
-MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor");
-MODULE_LICENSE("GPL v2");

drivers/iio/pressure/bmp280-i2c.c

@@ -0,0 +1,89 @@
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/acpi.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+#include "bmp280.h"
+
+static int bmp280_i2c_probe(struct i2c_client *client,
+			    const struct i2c_device_id *id)
+{
+	struct regmap *regmap;
+	const struct regmap_config *regmap_config;
+
+	switch (id->driver_data) {
+	case BMP180_CHIP_ID:
+		regmap_config = &bmp180_regmap_config;
+		break;
+	case BMP280_CHIP_ID:
+	case BME280_CHIP_ID:
+		regmap_config = &bmp280_regmap_config;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	regmap = devm_regmap_init_i2c(client, regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(&client->dev, "failed to allocate register map\n");
+		return PTR_ERR(regmap);
+	}
+
+	return bmp280_common_probe(&client->dev,
+				   regmap,
+				   id->driver_data,
+				   id->name);
+}
+
+static int bmp280_i2c_remove(struct i2c_client *client)
+{
+	return bmp280_common_remove(&client->dev);
+}
+
+static const struct acpi_device_id bmp280_acpi_i2c_match[] = {
+	{"BMP0280", BMP280_CHIP_ID },
+	{"BMP0180", BMP180_CHIP_ID },
+	{"BMP0085", BMP180_CHIP_ID },
+	{"BME0280", BME280_CHIP_ID },
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, bmp280_acpi_i2c_match);
+
+#ifdef CONFIG_OF
+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 },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, bmp280_of_i2c_match);
+#else
+#define bmp280_of_i2c_match NULL
+#endif
+
+static const struct i2c_device_id bmp280_i2c_id[] = {
+	{"bmp280", BMP280_CHIP_ID },
+	{"bmp180", BMP180_CHIP_ID },
+	{"bmp085", BMP180_CHIP_ID },
+	{"bme280", BME280_CHIP_ID },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, bmp280_i2c_id);
+
+static struct i2c_driver bmp280_i2c_driver = {
+	.driver = {
+		.name	= "bmp280",
+		.acpi_match_table = ACPI_PTR(bmp280_acpi_i2c_match),
+		.of_match_table = of_match_ptr(bmp280_of_i2c_match),
+	},
+	.probe		= bmp280_i2c_probe,
+	.remove		= bmp280_i2c_remove,
+	.id_table	= bmp280_i2c_id,
+};
+module_i2c_driver(bmp280_i2c_driver);
+
+MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
+MODULE_DESCRIPTION("Driver for Bosch Sensortec BMP180/BMP280 pressure and temperature sensor");
+MODULE_LICENSE("GPL v2");

drivers/iio/pressure/bmp280-regmap.c

@@ -0,0 +1,81 @@
+#include <linux/device.h>
+#include <linux/regmap.h>
+
+#include "bmp280.h"
+
+static bool bmp180_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case BMP280_REG_CTRL_MEAS:
+	case BMP280_REG_RESET:
+		return true;
+	default:
+		return false;
+	};
+}
+
+static bool bmp180_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case BMP180_REG_OUT_XLSB:
+	case BMP180_REG_OUT_LSB:
+	case BMP180_REG_OUT_MSB:
+	case BMP280_REG_CTRL_MEAS:
+		return true;
+	default:
+		return false;
+	}
+}
+
+const struct regmap_config bmp180_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = BMP180_REG_OUT_XLSB,
+	.cache_type = REGCACHE_RBTREE,
+
+	.writeable_reg = bmp180_is_writeable_reg,
+	.volatile_reg = bmp180_is_volatile_reg,
+};
+
+static bool bmp280_is_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case BMP280_REG_CONFIG:
+	case BMP280_REG_CTRL_HUMIDITY:
+	case BMP280_REG_CTRL_MEAS:
+	case BMP280_REG_RESET:
+		return true;
+	default:
+		return false;
+	};
+}
+
+static bool bmp280_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case BMP280_REG_HUMIDITY_LSB:
+	case BMP280_REG_HUMIDITY_MSB:
+	case BMP280_REG_TEMP_XLSB:
+	case BMP280_REG_TEMP_LSB:
+	case BMP280_REG_TEMP_MSB:
+	case BMP280_REG_PRESS_XLSB:
+	case BMP280_REG_PRESS_LSB:
+	case BMP280_REG_PRESS_MSB:
+	case BMP280_REG_STATUS:
+		return true;
+	default:
+		return false;
+	}
+}
+
+const struct regmap_config bmp280_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = BMP280_REG_HUMIDITY_LSB,
+	.cache_type = REGCACHE_RBTREE,
+
+	.writeable_reg = bmp280_is_writeable_reg,
+	.volatile_reg = bmp280_is_volatile_reg,
+};

drivers/iio/pressure/bmp280.h

@@ -0,0 +1,108 @@
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/regmap.h>
+
+/* BMP280 specific registers */
+#define BMP280_REG_HUMIDITY_LSB		0xFE
+#define BMP280_REG_HUMIDITY_MSB		0xFD
+#define BMP280_REG_TEMP_XLSB		0xFC
+#define BMP280_REG_TEMP_LSB		0xFB
+#define BMP280_REG_TEMP_MSB		0xFA
+#define BMP280_REG_PRESS_XLSB		0xF9
+#define BMP280_REG_PRESS_LSB		0xF8
+#define BMP280_REG_PRESS_MSB		0xF7
+
+#define BMP280_REG_CONFIG		0xF5
+#define BMP280_REG_CTRL_MEAS		0xF4
+#define BMP280_REG_STATUS		0xF3
+#define BMP280_REG_CTRL_HUMIDITY	0xF2
+
+/* Due to non linear mapping, and data sizes we can't do a bulk read */
+#define BMP280_REG_COMP_H1		0xA1
+#define BMP280_REG_COMP_H2		0xE1
+#define BMP280_REG_COMP_H3		0xE3
+#define BMP280_REG_COMP_H4		0xE4
+#define BMP280_REG_COMP_H5		0xE5
+#define BMP280_REG_COMP_H6		0xE7
+
+#define BMP280_REG_COMP_TEMP_START	0x88
+#define BMP280_COMP_TEMP_REG_COUNT	6
+
+#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_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_OSRS_HUMIDITY_MASK	(BIT(2) | BIT(1) | BIT(0))
+#define BMP280_OSRS_HUMIDITIY_X(osrs_h)	((osrs_h) << 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_TEMP_MASK		(BIT(7) | BIT(6) | BIT(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_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_MODE_SLEEP		0
+#define BMP280_MODE_FORCED		BIT(0)
+#define BMP280_MODE_NORMAL		(BIT(1) | BIT(0))
+
+/* BMP180 specific registers */
+#define BMP180_REG_OUT_XLSB		0xF8
+#define BMP180_REG_OUT_LSB		0xF7
+#define BMP180_REG_OUT_MSB		0xF6
+
+#define BMP180_REG_CALIB_START		0xAA
+#define BMP180_REG_CALIB_COUNT		22
+
+#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)
+
+/* BMP180 and BMP280 common registers */
+#define BMP280_REG_CTRL_MEAS		0xF4
+#define BMP280_REG_RESET		0xE0
+#define BMP280_REG_ID			0xD0
+
+#define BMP180_CHIP_ID			0x55
+#define BMP280_CHIP_ID			0x58
+#define BME280_CHIP_ID			0x60
+#define BMP280_SOFT_RESET_VAL		0xB6
+
+/* Regmap configurations */
+extern const struct regmap_config bmp180_regmap_config;
+extern const struct regmap_config bmp280_regmap_config;
+
+/* Probe called from different transports */
+int bmp280_common_probe(struct device *dev,
+			struct regmap *regmap,
+			unsigned int chip,
+			const char *name);
+int bmp280_common_remove(struct device *dev);