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[PATCH v3 3/6] iio: accel: adxl345: Add spi-3wire option

Lothar Rubusch posted 6 patches 1 year, 10 months ago
There is a newer version of this series
[PATCH v3 3/6] iio: accel: adxl345: Add spi-3wire option
Posted by Lothar Rubusch 1 year, 10 months ago 
Add a setup function implementation to the spi module to enable
spi-3wire as option when specified in the device-tree.

Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
---
 drivers/iio/accel/adxl345.h     |  3 +++
 drivers/iio/accel/adxl345_spi.c | 12 +++++++++++-
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/accel/adxl345.h b/drivers/iio/accel/adxl345.h
index 3c1ded0c2..6b84a2cee 100644
--- a/drivers/iio/accel/adxl345.h
+++ b/drivers/iio/accel/adxl345.h
@@ -8,6 +8,9 @@
 #ifndef _ADXL345_H_
 #define _ADXL345_H_
 
+#define ADXL345_REG_DATA_FORMAT		0x31
+#define ADXL345_DATA_FORMAT_SPI         BIT(6) /* spi-3wire */
+
 /*
  * In full-resolution mode, scale factor is maintained at ~4 mg/LSB
  * in all g ranges.
diff --git a/drivers/iio/accel/adxl345_spi.c b/drivers/iio/accel/adxl345_spi.c
index 1c0513bd3..1094396ac 100644
--- a/drivers/iio/accel/adxl345_spi.c
+++ b/drivers/iio/accel/adxl345_spi.c
@@ -20,6 +20,16 @@ static const struct regmap_config adxl345_spi_regmap_config = {
 	.read_flag_mask = BIT(7) | BIT(6),
 };
 
+static int adxl345_spi_setup(struct device *dev, struct regmap *regmap)
+{
+	struct spi_device *spi = container_of(dev, struct spi_device, dev);
+
+	if (spi->mode & SPI_3WIRE)
+		return regmap_write(regmap, ADXL345_REG_DATA_FORMAT,
+			    ADXL345_DATA_FORMAT_SPI);
+	return 0;
+}
+
 static int adxl345_spi_probe(struct spi_device *spi)
 {
 	struct regmap *regmap;
@@ -33,7 +43,7 @@ static int adxl345_spi_probe(struct spi_device *spi)
 	if (IS_ERR(regmap))
 		return dev_err_probe(&spi->dev, PTR_ERR(regmap), "Error initializing regmap\n");
 
-	return adxl345_core_probe(&spi->dev, regmap, NULL);
+	return adxl345_core_probe(&spi->dev, regmap, &adxl345_spi_setup);
 }
 
 static const struct adxl345_chip_info adxl345_spi_info = {
-- 
2.25.1
Re: [PATCH v3 3/6] iio: accel: adxl345: Add spi-3wire option
Posted by Jonathan Cameron 1 year, 10 months ago 
On Sat, 23 Mar 2024 12:20:27 +0000
Lothar Rubusch <l.rubusch@gmail.com> wrote:

> Add a setup function implementation to the spi module to enable
> spi-3wire as option when specified in the device-tree.
> 
> Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
> ---
>  drivers/iio/accel/adxl345.h     |  3 +++
>  drivers/iio/accel/adxl345_spi.c | 12 +++++++++++-
>  2 files changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/accel/adxl345.h b/drivers/iio/accel/adxl345.h
> index 3c1ded0c2..6b84a2cee 100644
> --- a/drivers/iio/accel/adxl345.h
> +++ b/drivers/iio/accel/adxl345.h
> @@ -8,6 +8,9 @@
>  #ifndef _ADXL345_H_
>  #define _ADXL345_H_
>  
> +#define ADXL345_REG_DATA_FORMAT		0x31
> +#define ADXL345_DATA_FORMAT_SPI         BIT(6) /* spi-3wire */
Name it that, rather than using a comment.   No need to precisely
match datasheet naming - you are naming the value not the field here.

ADXL345_DATA_FORMAT_SPI_3_WRITE perhaps?

> +
>  /*
>   * In full-resolution mode, scale factor is maintained at ~4 mg/LSB
>   * in all g ranges.
> diff --git a/drivers/iio/accel/adxl345_spi.c b/drivers/iio/accel/adxl345_spi.c
> index 1c0513bd3..1094396ac 100644
> --- a/drivers/iio/accel/adxl345_spi.c
> +++ b/drivers/iio/accel/adxl345_spi.c
> @@ -20,6 +20,16 @@ static const struct regmap_config adxl345_spi_regmap_config = {
>  	.read_flag_mask = BIT(7) | BIT(6),
>  };
>  
> +static int adxl345_spi_setup(struct device *dev, struct regmap *regmap)
> +{
> +	struct spi_device *spi = container_of(dev, struct spi_device, dev);
> +
> +	if (spi->mode & SPI_3WIRE)
> +		return regmap_write(regmap, ADXL345_REG_DATA_FORMAT,
> +			    ADXL345_DATA_FORMAT_SPI);
> +	return 0;
> +}
> +
>  static int adxl345_spi_probe(struct spi_device *spi)
>  {
>  	struct regmap *regmap;
> @@ -33,7 +43,7 @@ static int adxl345_spi_probe(struct spi_device *spi)
>  	if (IS_ERR(regmap))
>  		return dev_err_probe(&spi->dev, PTR_ERR(regmap), "Error initializing regmap\n");
>  
> -	return adxl345_core_probe(&spi->dev, regmap, NULL);
> +	return adxl345_core_probe(&spi->dev, regmap, &adxl345_spi_setup);
>  }
>  
>  static const struct adxl345_chip_info adxl345_spi_info = {
Re: [PATCH v3 3/6] iio: accel: adxl345: Add spi-3wire option
Posted by Lothar Rubusch 1 year, 10 months ago 
On Sun, Mar 24, 2024 at 2:32 PM Jonathan Cameron <jic23@kernel.org> wrote:
>
> On Sat, 23 Mar 2024 12:20:27 +0000
> Lothar Rubusch <l.rubusch@gmail.com> wrote:
>
> > Add a setup function implementation to the spi module to enable
> > spi-3wire as option when specified in the device-tree.
> >
> > Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
> > ---
> >  drivers/iio/accel/adxl345.h     |  3 +++
> >  drivers/iio/accel/adxl345_spi.c | 12 +++++++++++-
> >  2 files changed, 14 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/iio/accel/adxl345.h b/drivers/iio/accel/adxl345.h
> > index 3c1ded0c2..6b84a2cee 100644
> > --- a/drivers/iio/accel/adxl345.h
> > +++ b/drivers/iio/accel/adxl345.h
> > @@ -8,6 +8,9 @@
> >  #ifndef _ADXL345_H_
> >  #define _ADXL345_H_
> >
> > +#define ADXL345_REG_DATA_FORMAT              0x31
> > +#define ADXL345_DATA_FORMAT_SPI         BIT(6) /* spi-3wire */
> Name it that, rather than using a comment.   No need to precisely
> match datasheet naming - you are naming the value not the field here.
>
> ADXL345_DATA_FORMAT_SPI_3_WRITE perhaps?
>

Would you accept the following instead?
ADXL345_DATA_FORMAT_SPI_3WIRE

In the OF binding it is SPI_3WIRE. So, from this perspective I think it would
be consistent naming.

(...)
Re: [PATCH v3 3/6] iio: accel: adxl345: Add spi-3wire option
Posted by Jonathan Cameron 1 year, 10 months ago 
On Sun, 24 Mar 2024 19:59:39 +0100
Lothar Rubusch <l.rubusch@gmail.com> wrote:

> On Sun, Mar 24, 2024 at 2:32 PM Jonathan Cameron <jic23@kernel.org> wrote:
> >
> > On Sat, 23 Mar 2024 12:20:27 +0000
> > Lothar Rubusch <l.rubusch@gmail.com> wrote:
> >  
> > > Add a setup function implementation to the spi module to enable
> > > spi-3wire as option when specified in the device-tree.
> > >
> > > Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
> > > ---
> > >  drivers/iio/accel/adxl345.h     |  3 +++
> > >  drivers/iio/accel/adxl345_spi.c | 12 +++++++++++-
> > >  2 files changed, 14 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/iio/accel/adxl345.h b/drivers/iio/accel/adxl345.h
> > > index 3c1ded0c2..6b84a2cee 100644
> > > --- a/drivers/iio/accel/adxl345.h
> > > +++ b/drivers/iio/accel/adxl345.h
> > > @@ -8,6 +8,9 @@
> > >  #ifndef _ADXL345_H_
> > >  #define _ADXL345_H_
> > >
> > > +#define ADXL345_REG_DATA_FORMAT              0x31
> > > +#define ADXL345_DATA_FORMAT_SPI         BIT(6) /* spi-3wire */  
> > Name it that, rather than using a comment.   No need to precisely
> > match datasheet naming - you are naming the value not the field here.
> >
> > ADXL345_DATA_FORMAT_SPI_3_WRITE perhaps?
> >  
> 
> Would you accept the following instead?
> ADXL345_DATA_FORMAT_SPI_3WIRE
> 
> In the OF binding it is SPI_3WIRE. So, from this perspective I think it would
> be consistent naming.

That's fine.  Precise naming up to you.

Jonathan

> 
> (...)
>

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