Commit 83cb40be authored by Angel Iglesias's avatar Angel Iglesias Committed by Jonathan Cameron
Browse files

iio: pressure: bmp280: Simplify bmp280 calibration data reading 



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: default avatarAngel Iglesias <ang.iglesiasg@gmail.com>
Link: https://lore.kernel.org/r/96d81282c95006d857f4d836d2ff3ee0740a85a0.1663025017.git.ang.iglesiasg@gmail.com


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 2405f8cc

drivers/iio/pressure/bmp280-core.c

+23 −35
Original line number Diff line number Diff line
@@ -134,8 +134,7 @@ 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[] = {

	{
@@ -159,8 +158,7 @@ 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;
@@ -168,43 +166,33 @@ 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.

drivers/iio/pressure/bmp280.h

+3 −0
Original line number Diff line number Diff line
@@ -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