[PATCH v5 1/5] iio: pressure: bmp280: simplify driver initialization logic
From: Angel Iglesias
Date: Sun Aug 07 2022 - 07:54:54 EST
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.
Revised BMP180 and BMP280 definitions and code functions to use GENMASK
and FIELD_PREP/FIELD_GET utilities to homogenize structure with more
recent drivers, in preparation for the patches adding support for the
BMP380 sensors.
Suggested-by: Jonathan Cameron <jic23@xxxxxxxxxx>
Signed-off-by: Angel Iglesias <ang.iglesiasg@xxxxxxxxx>
---
drivers/iio/pressure/bmp280-core.c | 120 ++++++++++++++++++-----------
drivers/iio/pressure/bmp280.h | 73 +++++++++---------
2 files changed, 113 insertions(+), 80 deletions(-)
diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index fe7aa81e7cc9..a109c2609896 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>
@@ -107,19 +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 *, unsigned int);
};
/*
@@ -147,15 +158,14 @@ 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, unsigned int chip)
{
int ret;
unsigned int tmp;
__le16 l16;
__be16 b16;
struct device *dev = data->dev;
+ struct bmp280_calib *calib = &data->calib.bmp280;
__le16 t_buf[BMP280_COMP_TEMP_REG_COUNT / 2];
__le16 p_buf[BMP280_COMP_PRESS_REG_COUNT / 2];
@@ -611,8 +621,8 @@ 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);
+ u8 osrs = FIELD_PREP(BMP280_OSRS_TEMP_MASK, data->oversampling_temp + 1) |
+ FIELD_PREP(BMP280_OSRS_PRESS_MASK, data->oversampling_press + 1);
ret = regmap_write_bits(data->regmap, BMP280_REG_CTRL_MEAS,
BMP280_OSRS_TEMP_MASK |
@@ -640,21 +650,38 @@ 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)
{
int ret;
- u8 osrs = BMP280_OSRS_HUMIDITIY_X(data->oversampling_humid + 1);
+ u8 osrs = FIELD_PREP(BMP280_OSRS_HUMIDITY_MASK, data->oversampling_humid + 1);
/*
* Oversampling of humidity must be set before oversampling of
@@ -670,19 +697,27 @@ 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 = bmp280_read_calib,
};
static int bmp180_measure(struct bmp280_data *data, u8 ctrl_meas)
@@ -710,7 +745,7 @@ 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 =
@@ -735,7 +770,9 @@ 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;
@@ -748,11 +785,11 @@ 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, unsigned int chip)
{
int ret;
int i;
+ struct bmp180_calib *calib = &data->calib.bmp180;
__be16 buf[BMP180_REG_CALIB_COUNT / 2];
ret = regmap_bulk_read(data->regmap, BMP180_REG_CALIB_START, buf,
@@ -832,7 +869,10 @@ static int bmp180_read_adc_press(struct bmp280_data *data, int *val)
__be32 tmp = 0;
u8 oss = data->oversampling_press;
- 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;
@@ -913,17 +953,24 @@ 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)
@@ -993,6 +1040,7 @@ int bmp280_common_probe(struct device *dev,
int ret;
struct iio_dev *indio_dev;
struct bmp280_data *data;
+ const struct bmp280_chip_info *chip_info;
unsigned int chip_id;
struct gpio_desc *gpiod;
@@ -1011,30 +1059,25 @@ 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,
@@ -1071,7 +1114,8 @@ 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) {
@@ -1091,21 +1135,11 @@ 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, chip_id);
+ 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
diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
index 57ba0e85db91..5a19c7d04804 100644
--- a/drivers/iio/pressure/bmp280.h
+++ b/drivers/iio/pressure/bmp280.h
@@ -32,44 +32,41 @@
#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_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 +76,15 @@
#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
--
2.37.1