lkml.org 
[lkml]   [2022]   [Aug]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v5 1/5] iio: pressure: bmp280: simplify driver initialization logic
Date
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@kernel.org>
Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
---
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
\
 
 \ /
  Last update: 2022-08-07 13:55    [W:1.164 / U:0.648 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site