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-rw-r--r--drivers/iio/pressure/bmp280-core.c131
-rw-r--r--drivers/iio/pressure/bmp280.h4
2 files changed, 76 insertions, 59 deletions
diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index 067e56ba6c84..035a29871b7a 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -38,6 +38,8 @@
#include <linux/pm_runtime.h>
#include <linux/random.h>
+#include <asm/unaligned.h>
+
#include "bmp280.h"
/*
@@ -112,6 +114,21 @@ 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 {
@@ -166,13 +183,12 @@ 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");
@@ -180,23 +196,23 @@ 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;
}
@@ -206,8 +222,6 @@ 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 */
@@ -232,12 +246,13 @@ 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) {
@@ -246,20 +261,22 @@ 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) {
@@ -354,16 +371,16 @@ 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");
@@ -387,7 +404,6 @@ static int bmp280_read_press(struct bmp280_data *data,
int *val, int *val2)
{
u32 comp_press;
- __be32 tmp = 0;
s32 adc_press;
int ret;
@@ -396,13 +412,14 @@ 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");
@@ -420,7 +437,6 @@ 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. */
@@ -428,13 +444,14 @@ 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");
@@ -775,7 +792,6 @@ 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,
@@ -784,11 +800,12 @@ 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;
}
@@ -796,36 +813,36 @@ 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;
}
@@ -874,7 +891,6 @@ 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,
@@ -884,11 +900,12 @@ 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
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