diff mbox series

[1/2] drivers: iio: pressure: Fixes BMP38x and BMP390 SPI support

Message ID 20240220184125.32602-1-vassilisamir@gmail.com (mailing list archive)
State Accepted
Headers show
Series [1/2] drivers: iio: pressure: Fixes BMP38x and BMP390 SPI support | expand

Commit Message

Vasileios Amoiridis Feb. 20, 2024, 6:41 p.m. UTC
According to the datasheet of BMP38x and BMP390 devices, for an SPI
read operation the first byte that is returned needs to be dropped,
and the rest of the bytes are the actual data returned from the
sensor.

Fixes: 8d329309184d ("iio: pressure: bmp280: Add support for BMP380 sensor family")
Signed-off-by: Vasileios Amoiridis <vassilisamir@gmail.com>
---
 drivers/iio/pressure/bmp280-spi.c | 49 ++++++++++++++++++++++++++++++-
 1 file changed, 48 insertions(+), 1 deletion(-)

Comments

Andy Shevchenko Feb. 20, 2024, 7:57 p.m. UTC | #1
On Tue, Feb 20, 2024 at 07:41:24PM +0100, Vasileios Amoiridis wrote:
> According to the datasheet of BMP38x and BMP390 devices, for an SPI
> read operation the first byte that is returned needs to be dropped,
> and the rest of the bytes are the actual data returned from the
> sensor.

...

> +static int bmp380_regmap_spi_read(void *context, const void *reg,
> +				  size_t reg_size, void *val, size_t val_size)
> +{
> +	struct spi_device *spi = to_spi_device(context);
> +	u8 rx_buf[4];
> +	ssize_t status;
> +
> +	/*
> +	 * Maximum number of consecutive bytes read for a temperature or
> +	 * pressure measurement is 3.
> +	 */
> +	if (val_size > 3)
> +		return -EINVAL;

I would add a blank line here.

> +	/*
> +	 * According to the BMP3xx datasheets, for a basic SPI read opertion,
> +	 * the first byte needs to be dropped and the rest are the requested
> +	 * data.
> +	 */
> +	status = spi_write_then_read(spi, reg, 1, rx_buf, val_size + 1);
> +	if (status)
> +		return status;
> +
> +	memcpy(val, rx_buf + 1, val_size);
> +
> +	return 0;
> +}

With above and bits.h location being addressed
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Jonathan Cameron Feb. 24, 2024, 5:58 p.m. UTC | #2
On Tue, 20 Feb 2024 21:57:35 +0200
Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:

> On Tue, Feb 20, 2024 at 07:41:24PM +0100, Vasileios Amoiridis wrote:
> > According to the datasheet of BMP38x and BMP390 devices, for an SPI
> > read operation the first byte that is returned needs to be dropped,
> > and the rest of the bytes are the actual data returned from the
> > sensor.  
> 
> ...
> 
> > +static int bmp380_regmap_spi_read(void *context, const void *reg,
> > +				  size_t reg_size, void *val, size_t val_size)
> > +{
> > +	struct spi_device *spi = to_spi_device(context);
> > +	u8 rx_buf[4];
> > +	ssize_t status;
> > +
> > +	/*
> > +	 * Maximum number of consecutive bytes read for a temperature or
> > +	 * pressure measurement is 3.
> > +	 */
> > +	if (val_size > 3)
> > +		return -EINVAL;  
> 
> I would add a blank line here.
> 
> > +	/*
> > +	 * According to the BMP3xx datasheets, for a basic SPI read opertion,
> > +	 * the first byte needs to be dropped and the rest are the requested
> > +	 * data.
> > +	 */
> > +	status = spi_write_then_read(spi, reg, 1, rx_buf, val_size + 1);
> > +	if (status)
> > +		return status;
> > +
> > +	memcpy(val, rx_buf + 1, val_size);
> > +
> > +	return 0;
> > +}  
> 
> With above and bits.h location being addressed
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> 
I'd picked up previous version and tweaked it for the header being first.
Now updated the spacing above and added your tag.

Only did this rebase because it was the top of my fixes tree.
diff mbox series

Patch

diff --git a/drivers/iio/pressure/bmp280-spi.c b/drivers/iio/pressure/bmp280-spi.c
index e8a5fed07e88..1972014dca93 100644
--- a/drivers/iio/pressure/bmp280-spi.c
+++ b/drivers/iio/pressure/bmp280-spi.c
@@ -8,6 +8,7 @@ 
 #include <linux/spi/spi.h>
 #include <linux/err.h>
 #include <linux/regmap.h>
+#include <linux/bits.h>
 
 #include "bmp280.h"
 
@@ -35,6 +36,33 @@  static int bmp280_regmap_spi_read(void *context, const void *reg,
 	return spi_write_then_read(spi, reg, reg_size, val, val_size);
 }
 
+static int bmp380_regmap_spi_read(void *context, const void *reg,
+				  size_t reg_size, void *val, size_t val_size)
+{
+	struct spi_device *spi = to_spi_device(context);
+	u8 rx_buf[4];
+	ssize_t status;
+
+	/*
+	 * Maximum number of consecutive bytes read for a temperature or
+	 * pressure measurement is 3.
+	 */
+	if (val_size > 3)
+		return -EINVAL;
+	/*
+	 * According to the BMP3xx datasheets, for a basic SPI read opertion,
+	 * the first byte needs to be dropped and the rest are the requested
+	 * data.
+	 */
+	status = spi_write_then_read(spi, reg, 1, rx_buf, val_size + 1);
+	if (status)
+		return status;
+
+	memcpy(val, rx_buf + 1, val_size);
+
+	return 0;
+}
+
 static struct regmap_bus bmp280_regmap_bus = {
 	.write = bmp280_regmap_spi_write,
 	.read = bmp280_regmap_spi_read,
@@ -42,10 +70,19 @@  static struct regmap_bus bmp280_regmap_bus = {
 	.val_format_endian_default = REGMAP_ENDIAN_BIG,
 };
 
+static struct regmap_bus bmp380_regmap_bus = {
+	.write = bmp280_regmap_spi_write,
+	.read = bmp380_regmap_spi_read,
+	.read_flag_mask = BIT(7),
+	.reg_format_endian_default = REGMAP_ENDIAN_BIG,
+	.val_format_endian_default = REGMAP_ENDIAN_BIG,
+};
+
 static int bmp280_spi_probe(struct spi_device *spi)
 {
 	const struct spi_device_id *id = spi_get_device_id(spi);
 	const struct bmp280_chip_info *chip_info;
+	struct regmap_bus *bmp_regmap_bus;
 	struct regmap *regmap;
 	int ret;
 
@@ -58,8 +95,18 @@  static int bmp280_spi_probe(struct spi_device *spi)
 
 	chip_info = spi_get_device_match_data(spi);
 
+	switch (chip_info->chip_id[0]) {
+	case BMP380_CHIP_ID:
+	case BMP390_CHIP_ID:
+		bmp_regmap_bus = &bmp380_regmap_bus;
+		break;
+	default:
+		bmp_regmap_bus = &bmp280_regmap_bus;
+		break;
+	}
+
 	regmap = devm_regmap_init(&spi->dev,
-				  &bmp280_regmap_bus,
+				  bmp_regmap_bus,
 				  &spi->dev,
 				  chip_info->regmap_config);
 	if (IS_ERR(regmap)) {