[PATCH 0/2] iio: pressure: changes to mprls0025pa

[PATCH 0/2] iio: pressure: changes to mprls0025pa

[Petre Rodan]

ChangeLog
 - rewrite flow so that driver can use either i2c or spi as communication bus
 - add spi driver (tested on MPRLS0015PA0000SA)
 - add pressure-triplet property that automatically sets pmin, pmax
 - fix transfer-function enum typo based on previous review [1]
 - fix interrupt example in binding file (FALLING -> RISING edge)
 - indentation changes based on previous code reviews
 - renamed mpr_read_pressure to mpr_read_conversion since the sensor is
   supposed to also provide temperature measuremets
   (but I think mine is broken since the raw temperature value is always
   0x800000 - so temp reading not currently implemented)

patch uses device_property_match_property_string() from the 'togreg' branch

[1]: https://lore.kernel.org/lkml/20231116-grudge-hankering-b7a71d831b93@squawk/T/

Petre Rodan (2):
  dt-bindings: iio: pressure: change honeywell,mprls0025pa
  iio: pressure: change driver for Honeywell MPR series

 .../iio/pressure/honeywell,mprls0025pa.yaml   |  60 ++-
 MAINTAINERS                                   |   3 +-
 drivers/iio/pressure/Kconfig                  |  14 +-
 drivers/iio/pressure/Makefile                 |   2 +
 drivers/iio/pressure/mprls0025pa.c            | 353 +++++++++---------
 drivers/iio/pressure/mprls0025pa.h            | 103 +++++
 drivers/iio/pressure/mprls0025pa_i2c.c        |  76 ++++
 drivers/iio/pressure/mprls0025pa_spi.c        |  67 ++++
 8 files changed, 491 insertions(+), 187 deletions(-)
 create mode 100644 drivers/iio/pressure/mprls0025pa.h
 create mode 100644 drivers/iio/pressure/mprls0025pa_i2c.c
 create mode 100644 drivers/iio/pressure/mprls0025pa_spi.c

-- 
2.41.0

[PATCH 1/2] dt-bindings: iio: pressure: honeywell,mprls0025pa

[Petre Rodan]

ChangeLog
 - add honeywell,pressure-triplet property that autoconfigures pmin, pmax
    just like the hsc030pa sensor driver
 - add support for spi-based sensors

Datasheet:
https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
 .../iio/pressure/honeywell,mprls0025pa.yaml   | 60 ++++++++++++++++---
 1 file changed, 52 insertions(+), 8 deletions(-)

diff --git a/Documentation/devicetree/bindings/iio/pressure/honeywell,mprls0025pa.yaml b/Documentation/devicetree/bindings/iio/pressure/honeywell,mprls0025pa.yaml
index d9e903fbfd99..7c4be2dec174 100644
--- a/Documentation/devicetree/bindings/iio/pressure/honeywell,mprls0025pa.yaml
+++ b/Documentation/devicetree/bindings/iio/pressure/honeywell,mprls0025pa.yaml
@@ -53,33 +53,59 @@ properties:
   honeywell,pmin-pascal:
     description:
       Minimum pressure value the sensor can measure in pascal.
+      To be specified only if honeywell,pressure-triplet is set to "NA".
 
   honeywell,pmax-pascal:
     description:
       Maximum pressure value the sensor can measure in pascal.
+      To be specified only if honeywell,pressure-triplet is set to "NA".
 
   honeywell,transfer-function:
     description: |
-      Transfer function which defines the range of valid values delivered by the
-      sensor.
+      Transfer function which defines the range of valid values delivered by
+      the sensor.
       1 - A, 10% to 90% of 2^24 (1677722 .. 15099494)
       2 - B, 2.5% to 22.5% of 2^24 (419430 .. 3774874)
       3 - C, 20% to 80% of 2^24 (3355443 .. 13421773)
+    enum: [1, 2, 3]
     $ref: /schemas/types.yaml#/definitions/uint32
 
+  honeywell,pressure-triplet:
+    description: |
+      Case-sensitive five character string that defines pressure range, unit
+      and type as part of the device nomenclature. In the unlikely case of a
+      custom chip, set to "NA" and provide pmin-pascal and pmax-pascal.
+    enum: [0001BA, 01.6BA, 02.5BA, 0060MG, 0100MG, 0160MG, 0250MG, 0400MG,
+           0600MG, 0001BG, 01.6BG, 02.5BG, 0100KA, 0160KA, 0250KA, 0006KG,
+           0010KG, 0016KG, 0025KG, 0040KG, 0060KG, 0100KG, 0160KG, 0250KG,
+           0015PA, 0025PA, 0030PA, 0001PG, 0005PG, 0015PG, 0030PG, 0300YG,
+           NA]
+    $ref: /schemas/types.yaml#/definitions/string
+
+  spi-max-frequency:
+    maximum: 800000
+
   vdd-supply:
     description: provide VDD power to the sensor.
 
 required:
   - compatible
   - reg
-  - honeywell,pmin-pascal
-  - honeywell,pmax-pascal
+  - honeywell,pressure-triplet
   - honeywell,transfer-function
-  - vdd-supply
 
 additionalProperties: false
 
+dependentSchemas:
+  honeywell,pmin-pascal:
+    properties:
+      honeywell,pressure-triplet:
+        const: NA
+  honeywell,pmax-pascal:
+    properties:
+      honeywell,pressure-triplet:
+        const: NA
+
 examples:
   - |
     #include <dt-bindings/gpio/gpio.h>
@@ -93,10 +119,28 @@ examples:
             reg = <0x18>;
             reset-gpios = <&gpio3 19 GPIO_ACTIVE_HIGH>;
             interrupt-parent = <&gpio3>;
-            interrupts = <21 IRQ_TYPE_EDGE_FALLING>;
-            honeywell,pmin-pascal = <0>;
-            honeywell,pmax-pascal = <172369>;
+            interrupts = <21 IRQ_TYPE_EDGE_RISING>;
+
+            honeywell,pressure-triplet = "0025PA";
             honeywell,transfer-function = <1>;
             vdd-supply = <&vcc_3v3>;
         };
     };
+  - |
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        pressure@0 {
+            compatible = "honeywell,mprls0025pa";
+            reg = <0>;
+            spi-max-frequency = <800000>;
+            reset-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
+            interrupt-parent = <&gpio0>;
+            interrupts = <30 IRQ_TYPE_EDGE_RISING>;
+
+            honeywell,pressure-triplet = "0015PA";
+            honeywell,transfer-function = <1>;
+        };
+    };
+...
-- 
2.41.0

Re: [PATCH 1/2] dt-bindings: iio: pressure: honeywell,mprls0025pa

[Jonathan Cameron]

On Tue, 19 Dec 2023 15:02:20 +0200
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> ChangeLog

The whole patch description describes changes, so no need for a Changelog heading.

>  - add honeywell,pressure-triplet property that autoconfigures pmin, pmax
>     just like the hsc030pa sensor driver

Why?  Needs an explanation of why this binding is better and easier to use
+ how backwards compatibility is maintained.

>  - add support for spi-based sensors
> 
Two things, two patches.

> Datasheet:

It's a formal tag, so no line break (Even if checkpatch complains!)

> https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
> ---
>  .../iio/pressure/honeywell,mprls0025pa.yaml   | 60 ++++++++++++++++---
>  1 file changed, 52 insertions(+), 8 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/iio/pressure/honeywell,mprls0025pa.yaml b/Documentation/devicetree/bindings/iio/pressure/honeywell,mprls0025pa.yaml
> index d9e903fbfd99..7c4be2dec174 100644
> --- a/Documentation/devicetree/bindings/iio/pressure/honeywell,mprls0025pa.yaml
> +++ b/Documentation/devicetree/bindings/iio/pressure/honeywell,mprls0025pa.yaml
> @@ -53,33 +53,59 @@ properties:
>    honeywell,pmin-pascal:
>      description:
>        Minimum pressure value the sensor can measure in pascal.
> +      To be specified only if honeywell,pressure-triplet is set to "NA".
That just added a backwards compatibility break.  It would be fine
if there was a default: NA for honeywell,pressure-triplet or a check that either
one or the other was supplied (which I'd prefer).  Thus old bindings will work
and new ones also supported.

>  
>    honeywell,pmax-pascal:
>      description:
>        Maximum pressure value the sensor can measure in pascal.
> +      To be specified only if honeywell,pressure-triplet is set to "NA".
>  
>    honeywell,transfer-function:
>      description: |
> -      Transfer function which defines the range of valid values delivered by the
> -      sensor.
> +      Transfer function which defines the range of valid values delivered by
> +      the sensor.
>        1 - A, 10% to 90% of 2^24 (1677722 .. 15099494)
>        2 - B, 2.5% to 22.5% of 2^24 (419430 .. 3774874)
>        3 - C, 20% to 80% of 2^24 (3355443 .. 13421773)
> +    enum: [1, 2, 3]
>      $ref: /schemas/types.yaml#/definitions/uint32
>  
> +  honeywell,pressure-triplet:
> +    description: |
> +      Case-sensitive five character string that defines pressure range, unit
> +      and type as part of the device nomenclature. In the unlikely case of a
> +      custom chip, set to "NA" and provide pmin-pascal and pmax-pascal.

Should not need to set to NA, just don't provide it.

> +    enum: [0001BA, 01.6BA, 02.5BA, 0060MG, 0100MG, 0160MG, 0250MG, 0400MG,
> +           0600MG, 0001BG, 01.6BG, 02.5BG, 0100KA, 0160KA, 0250KA, 0006KG,
> +           0010KG, 0016KG, 0025KG, 0040KG, 0060KG, 0100KG, 0160KG, 0250KG,
> +           0015PA, 0025PA, 0030PA, 0001PG, 0005PG, 0015PG, 0030PG, 0300YG,
> +           NA]
> +    $ref: /schemas/types.yaml#/definitions/string
> +
> +  spi-max-frequency:
> +    maximum: 800000
> +
>    vdd-supply:
>      description: provide VDD power to the sensor.
>  
>  required:
>    - compatible
>    - reg
> -  - honeywell,pmin-pascal
> -  - honeywell,pmax-pascal
> +  - honeywell,pressure-triplet
>    - honeywell,transfer-function
> -  - vdd-supply
>  
>  additionalProperties: false
>  
> +dependentSchemas:
> +  honeywell,pmin-pascal:
> +    properties:
> +      honeywell,pressure-triplet:
> +        const: NA
> +  honeywell,pmax-pascal:
> +    properties:
> +      honeywell,pressure-triplet:
> +        const: NA
> +
>  examples:
>    - |
>      #include <dt-bindings/gpio/gpio.h>
> @@ -93,10 +119,28 @@ examples:
>              reg = <0x18>;
>              reset-gpios = <&gpio3 19 GPIO_ACTIVE_HIGH>;
>              interrupt-parent = <&gpio3>;
> -            interrupts = <21 IRQ_TYPE_EDGE_FALLING>;
> -            honeywell,pmin-pascal = <0>;
> -            honeywell,pmax-pascal = <172369>;
> +            interrupts = <21 IRQ_TYPE_EDGE_RISING>;
> +
> +            honeywell,pressure-triplet = "0025PA";
>              honeywell,transfer-function = <1>;
>              vdd-supply = <&vcc_3v3>;
>          };
>      };
> +  - |
> +    spi {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        pressure@0 {
> +            compatible = "honeywell,mprls0025pa";
> +            reg = <0>;
> +            spi-max-frequency = <800000>;
> +            reset-gpios = <&gpio1 28 GPIO_ACTIVE_HIGH>;
> +            interrupt-parent = <&gpio0>;
> +            interrupts = <30 IRQ_TYPE_EDGE_RISING>;
> +
> +            honeywell,pressure-triplet = "0015PA";
> +            honeywell,transfer-function = <1>;
> +        };
> +    };
> +...

Re: [PATCH 1/2] dt-bindings: iio: pressure: honeywell,mprls0025pa

[Petre Rodan]

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hi Jonathan,

On Wed, Dec 20, 2023 at 03:16:45PM +0000, Jonathan Cameron wrote:
> On Tue, 19 Dec 2023 15:02:20 +0200
> Petre Rodan <petre.rodan@subdimension.ro> wrote:
> >    honeywell,pmin-pascal:
> >      description:
> >        Minimum pressure value the sensor can measure in pascal.
> > +      To be specified only if honeywell,pressure-triplet is set to "NA".
> That just added a backwards compatibility break.  It would be fine
> if there was a default: NA for honeywell,pressure-triplet or a check that either
> one or the other was supplied (which I'd prefer).  Thus old bindings will work
> and new ones also supported.

ok, I see your reasoning. but in this second scenario that you prefer how can we
propery define the 'required:' block? an equivalent to

required:
  - compatible
  - reg
  - (honeywell,pmin-pascal && honeywell,pmax-pascal) || honeywell,pressure-triplet
  - honeywell,transfer-function


thanks,
peter

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Re: [PATCH 1/2] dt-bindings: iio: pressure: honeywell,mprls0025pa

[Jonathan Cameron]

On Wed, 20 Dec 2023 19:25:25 +0200
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> hi Jonathan,
> 
> On Wed, Dec 20, 2023 at 03:16:45PM +0000, Jonathan Cameron wrote:
> > On Tue, 19 Dec 2023 15:02:20 +0200
> > Petre Rodan <petre.rodan@subdimension.ro> wrote:  
> > >    honeywell,pmin-pascal:
> > >      description:
> > >        Minimum pressure value the sensor can measure in pascal.
> > > +      To be specified only if honeywell,pressure-triplet is set to "NA".  
> > That just added a backwards compatibility break.  It would be fine
> > if there was a default: NA for honeywell,pressure-triplet or a check that either
> > one or the other was supplied (which I'd prefer).  Thus old bindings will work
> > and new ones also supported.  
> 
> ok, I see your reasoning. but in this second scenario that you prefer how can we
> propery define the 'required:' block? an equivalent to
> 
> required:
>   - compatible
>   - reg
>   - (honeywell,pmin-pascal && honeywell,pmax-pascal) || honeywell,pressure-triplet
>   - honeywell,transfer-function

Yes, it would end up something like that.  There are exclusive or examples in tree.
I think something like dac/adi,ad3552r.yaml
 should work.

oneOf:
  - required:
      - honeywell,pmin-pascal
      - honeywell,pmax-pascal
  - required:
      - honeywell,pressure-triplet

but you will want to try all the cases to make sure that works (my ability to
figure these ones out is tricky).

+ you ideally want to exclude them all being set which is fiddlier.

Some similar examples but they are based on a value in the property. I'm not
sure how you check for it just being defined.

Something along lines of.

allOf:
  - if:
      properties:
        honeywell,pressure-triplet
    then:
      properties:
        honeywell,pmin-pascal: false
        honeywell,pmax-pascal: false

Might work?  I always end up trawling the kernel to find a similar example for cases but
can't find anything closer right now.

Jonathan

   



> 
> 
> thanks,
> peter

Re: [PATCH 1/2] dt-bindings: iio: pressure: honeywell,mprls0025pa

[Conor Dooley]

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On Thu, Dec 21, 2023 at 11:04:17AM +0000, Jonathan Cameron wrote:
> On Wed, 20 Dec 2023 19:25:25 +0200
> Petre Rodan <petre.rodan@subdimension.ro> wrote:
> 
> > hi Jonathan,
> > 
> > On Wed, Dec 20, 2023 at 03:16:45PM +0000, Jonathan Cameron wrote:
> > > On Tue, 19 Dec 2023 15:02:20 +0200
> > > Petre Rodan <petre.rodan@subdimension.ro> wrote:  
> > > >    honeywell,pmin-pascal:
> > > >      description:
> > > >        Minimum pressure value the sensor can measure in pascal.
> > > > +      To be specified only if honeywell,pressure-triplet is set to "NA".  
> > > That just added a backwards compatibility break.  It would be fine
> > > if there was a default: NA for honeywell,pressure-triplet or a check that either
> > > one or the other was supplied (which I'd prefer).  Thus old bindings will work
> > > and new ones also supported.  
> > 
> > ok, I see your reasoning. but in this second scenario that you prefer how can we
> > propery define the 'required:' block? an equivalent to
> > 
> > required:
> >   - compatible
> >   - reg
> >   - (honeywell,pmin-pascal && honeywell,pmax-pascal) || honeywell,pressure-triplet
> >   - honeywell,transfer-function
> 
> Yes, it would end up something like that.  There are exclusive or examples in tree.
> I think something like dac/adi,ad3552r.yaml
>  should work.
> 
> oneOf:
>   - required:
>       - honeywell,pmin-pascal
>       - honeywell,pmax-pascal
>   - required:
>       - honeywell,pressure-triplet
> 
> but you will want to try all the cases to make sure that works (my ability to
> figure these ones out is tricky).
> 
> + you ideally want to exclude them all being set which is fiddlier.
> 
> Some similar examples but they are based on a value in the property. I'm not
> sure how you check for it just being defined.
> 
> Something along lines of.
> 
> allOf:
>   - if:
>       properties:
>         honeywell,pressure-triplet
>     then:
>       properties:
>         honeywell,pmin-pascal: false
>         honeywell,pmax-pascal: false
> 
> Might work?  I always end up trawling the kernel to find a similar example for cases but
> can't find anything closer right now.

I hate to admit it, but I'm not great at expressing these in the minimum
forms either, but I think you're missing a "required" from here, in place
of the "properties":
allOf:
  - if:
      required:
        - honeywell,pressure-triplet
    then:
      properties:
        honeywell,pmin-pascal: false
        honeywell,pmax-pascal: false

Cheers,
Conor.

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Re: [PATCH 1/2] dt-bindings: iio: pressure: honeywell,mprls0025pa

[Petre Rodan]

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hello Conor,

On Fri, Dec 22, 2023 at 03:27:36PM +0000, Conor Dooley wrote:
> > >   - (honeywell,pmin-pascal && honeywell,pmax-pascal) || honeywell,pressure-triplet
> > Yes, it would end up something like that.  There are exclusive or examples in tree.

> > oneOf:
> >   - required:
> >       - honeywell,pmin-pascal
> >       - honeywell,pmax-pascal
> >   - required:
> >       - honeywell,pressure-triplet
> > 
> > but you will want to try all the cases to make sure that works (my ability to
> > figure these ones out is tricky).
> > 
> > + you ideally want to exclude them all being set which is fiddlier.
> > 
> > Some similar examples but they are based on a value in the property. I'm not
> > sure how you check for it just being defined.
> > 
> > Something along lines of.
> > 
> > allOf:
> >   - if:
> >       properties:
> >         honeywell,pressure-triplet
> >     then:
> >       properties:
> >         honeywell,pmin-pascal: false
> >         honeywell,pmax-pascal: false
> > 
> > Might work?  I always end up trawling the kernel to find a similar example for cases but
> > can't find anything closer right now.
> 
> I hate to admit it, but I'm not great at expressing these in the minimum
> forms either, but I think you're missing a "required" from here, in place
> of the "properties":
> allOf:
>   - if:
>       required:
>         - honeywell,pressure-triplet
>     then:
>       properties:
>         honeywell,pmin-pascal: false
>         honeywell,pmax-pascal: false

thank you both for the above ruleset, it works like magic.

I spent hours trying to figure out the proper syntax but never got it right.

Merry Christmas!
peter

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[PATCH 2/2] iio: pressure: change driver for Honeywell MPR series

[Petre Rodan]

ChangeLog
 - rewrite flow so that driver can use either i2c or spi as communication bus
 - add spi driver (tested on MPRLS0015PA0000SA)
 - add pressure-triplet property that automatically sets pmin, pmax
 - fix transfer-function enum typo based on previous review [1]
 - fix interrupt example in binding file (FALLING -> RISING edge)
 - indentation changes based on previous code reviews
 - renamed mpr_read_pressure to mpr_read_conversion since the sensor is
   supposed to also provide temperature measuremets
   (but I think mine is broken since the raw temperature value is always
   0x800000 - so temp reading not currently implemented)

I've been told in the past that the use of mutexes is redundant in these cases
so please assess if the guard() from the driver code is required or should be
removed.

patch uses device_property_match_property_string() from the 'togreg' branch

[1]: https://lore.kernel.org/lkml/20231116-grudge-hankering-b7a71d831b93@squawk/T/
Datasheet:
https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>
---
 MAINTAINERS                            |   3 +-
 drivers/iio/pressure/Kconfig           |  14 +-
 drivers/iio/pressure/Makefile          |   2 +
 drivers/iio/pressure/mprls0025pa.c     | 353 ++++++++++++-------------
 drivers/iio/pressure/mprls0025pa.h     | 103 ++++++++
 drivers/iio/pressure/mprls0025pa_i2c.c |  76 ++++++
 drivers/iio/pressure/mprls0025pa_spi.c |  67 +++++
 7 files changed, 439 insertions(+), 179 deletions(-)
 create mode 100644 drivers/iio/pressure/mprls0025pa.h
 create mode 100644 drivers/iio/pressure/mprls0025pa_i2c.c
 create mode 100644 drivers/iio/pressure/mprls0025pa_spi.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 3029841e92a8..cbb163e1b311 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9725,10 +9725,11 @@ F:	drivers/iio/pressure/hsc030pa*
 
 HONEYWELL MPRLS0025PA PRESSURE SENSOR SERIES IIO DRIVER
 M:	Andreas Klinger <ak@it-klinger.de>
+M:	Petre Rodan <petre.rodan@subdimension.ro>
 L:	linux-iio@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/iio/pressure/honeywell,mprls0025pa.yaml
-F:	drivers/iio/pressure/mprls0025pa.c
+F:	drivers/iio/pressure/mprls0025pa*
 
 HOST AP DRIVER
 L:	linux-wireless@vger.kernel.org
diff --git a/drivers/iio/pressure/Kconfig b/drivers/iio/pressure/Kconfig
index 79adfd059c3a..5da7931dc537 100644
--- a/drivers/iio/pressure/Kconfig
+++ b/drivers/iio/pressure/Kconfig
@@ -181,7 +181,9 @@ config MPL3115
 
 config MPRLS0025PA
 	tristate "Honeywell MPRLS0025PA (MicroPressure sensors series)"
-	depends on I2C
+	depends on (I2C || SPI_MASTER)
+	select MPRLS0025PA_I2C if I2C
+	select MPRLS0025PA_SPI if SPI_MASTER
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
 	help
@@ -192,6 +194,16 @@ config MPRLS0025PA
 	  To compile this driver as a module, choose M here: the module will be
 	  called mprls0025pa.
 
+config MPRLS0025PA_I2C
+	tristate
+	depends on MPRLS0025PA
+	depends on I2C
+
+config MPRLS0025PA_SPI
+	tristate
+	depends on MPRLS0025PA
+	depends on SPI_MASTER
+
 config MS5611
 	tristate "Measurement Specialties MS5611 pressure sensor driver"
 	select IIO_BUFFER
diff --git a/drivers/iio/pressure/Makefile b/drivers/iio/pressure/Makefile
index b0f8b94662f2..a93709e35760 100644
--- a/drivers/iio/pressure/Makefile
+++ b/drivers/iio/pressure/Makefile
@@ -24,6 +24,8 @@ obj-$(CONFIG_MPL115_I2C) += mpl115_i2c.o
 obj-$(CONFIG_MPL115_SPI) += mpl115_spi.o
 obj-$(CONFIG_MPL3115) += mpl3115.o
 obj-$(CONFIG_MPRLS0025PA) += mprls0025pa.o
+obj-$(CONFIG_MPRLS0025PA_I2C) += mprls0025pa_i2c.o
+obj-$(CONFIG_MPRLS0025PA_SPI) += mprls0025pa_spi.o
 obj-$(CONFIG_MS5611) += ms5611_core.o
 obj-$(CONFIG_MS5611_I2C) += ms5611_i2c.o
 obj-$(CONFIG_MS5611_SPI) += ms5611_spi.o
diff --git a/drivers/iio/pressure/mprls0025pa.c b/drivers/iio/pressure/mprls0025pa.c
index 30fb2de36821..4a999bf73964 100644
--- a/drivers/iio/pressure/mprls0025pa.c
+++ b/drivers/iio/pressure/mprls0025pa.c
@@ -5,17 +5,14 @@
  * Copyright (c) Andreas Klinger <ak@it-klinger.de>
  *
  * Data sheet:
- *  https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/
- *    products/sensors/pressure-sensors/board-mount-pressure-sensors/
- *    micropressure-mpr-series/documents/
- *    sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
+ *  https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
  *
- * 7-bit I2C default slave address: 0x18
  */
 
-#include <linux/delay.h>
-#include <linux/device.h>
-#include <linux/i2c.h>
+#include <linux/array_size.h>
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/cleanup.h>
 #include <linux/math64.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
@@ -33,11 +30,7 @@
 
 #include <asm/unaligned.h>
 
-/* bits in i2c status byte */
-#define MPR_I2C_POWER	BIT(6)	/* device is powered */
-#define MPR_I2C_BUSY	BIT(5)	/* device is busy */
-#define MPR_I2C_MEMORY	BIT(2)	/* integrity test passed */
-#define MPR_I2C_MATH	BIT(0)	/* internal math saturation */
+#include "mprls0025pa.h"
 
 /*
  * support _RAW sysfs interface:
@@ -65,73 +58,102 @@
  *                which reduces the offset to (-1 * outputmin)
  */
 
+#define MPR_PRESSURE_MASK GENMASK(23, 0)
+
+struct mpr_func_spec {
+	u32 output_min;
+	u32 output_max;
+};
+
 /*
  * transfer function A: 10%   to 90%   of 2^24
  * transfer function B:  2.5% to 22.5% of 2^24
  * transfer function C: 20%   to 80%   of 2^24
  */
-enum mpr_func_id {
-	MPR_FUNCTION_A,
-	MPR_FUNCTION_B,
-	MPR_FUNCTION_C,
+static const struct mpr_func_spec mpr_func_spec[] = {
+	[MPR_FUNCTION_A] = { .output_min = 1677722, .output_max = 15099494 },
+	[MPR_FUNCTION_B] = { .output_min =  419430, .output_max =  3774874 },
+	[MPR_FUNCTION_C] = { .output_min = 3355443, .output_max = 13421773 },
 };
 
-struct mpr_func_spec {
-	u32			output_min;
-	u32			output_max;
+enum mpr_variants {
+	MPR0001BA = 0x00, MPR01_6BA = 0x01, MPR02_5BA = 0x02, MPR0060MG = 0x03,
+	MPR0100MG = 0x04, MPR0160MG = 0x05, MPR0250MG = 0x06, MPR0400MG = 0x07,
+	MPR0600MG = 0x08, MPR0001BG = 0x09, MPR01_6BG = 0x0a, MPR02_5BG = 0x0b,
+	MPR0100KA = 0x0c, MPR0160KA = 0x0d, MPR0250KA = 0x0e, MPR0006KG = 0x0f,
+	MPR0010KG = 0x10, MPR0016KG = 0x11, MPR0025KG = 0x12, MPR0040KG = 0x13,
+	MPR0060KG = 0x14, MPR0100KG = 0x15, MPR0160KG = 0x16, MPR0250KG = 0x17,
+	MPR0015PA = 0x18, MPR0025PA = 0x19, MPR0030PA = 0x1a, MPR0001PG = 0x1b,
+	MPR0005PG = 0x1c, MPR0015PG = 0x1d, MPR0030PG = 0x1e, MPR0300YG = 0x1f,
+	MPR_VARIANTS_MAX
 };
 
-static const struct mpr_func_spec mpr_func_spec[] = {
-	[MPR_FUNCTION_A] = {.output_min = 1677722, .output_max = 15099494},
-	[MPR_FUNCTION_B] = {.output_min =  419430, .output_max =  3774874},
-	[MPR_FUNCTION_C] = {.output_min = 3355443, .output_max = 13421773},
+static const char * const mpr_triplet_variants[MPR_VARIANTS_MAX] = {
+	[MPR0001BA] = "0001BA", [MPR01_6BA] = "01.6BA", [MPR02_5BA] = "02.5BA",
+	[MPR0060MG] = "0060MG", [MPR0100MG] = "0100MG", [MPR0160MG] = "0160MG",
+	[MPR0250MG] = "0250MG", [MPR0400MG] = "0400MG", [MPR0600MG] = "0600MG",
+	[MPR0001BG] = "0001BG", [MPR01_6BG] = "01.6BG", [MPR02_5BG] = "02.5BG",
+	[MPR0100KA] = "0100KA", [MPR0160KA] = "0160KA", [MPR0250KA] = "0250KA",
+	[MPR0006KG] = "0006KG", [MPR0010KG] = "0010KG", [MPR0016KG] = "0016KG",
+	[MPR0025KG] = "0025KG", [MPR0040KG] = "0040KG", [MPR0060KG] = "0060KG",
+	[MPR0100KG] = "0100KG", [MPR0160KG] = "0160KG", [MPR0250KG] = "0250KG",
+	[MPR0015PA] = "0015PA", [MPR0025PA] = "0025PA", [MPR0030PA] = "0030PA",
+	[MPR0001PG] = "0001PG", [MPR0005PG] = "0005PG", [MPR0015PG] = "0015PG",
+	[MPR0030PG] = "0030PG", [MPR0300YG] = "0300YG"
 };
 
-struct mpr_chan {
-	s32			pres;		/* pressure value */
-	s64			ts;		/* timestamp */
+/**
+ * struct mpr_range_config - list of pressure ranges based on nomenclature
+ * @pmin: lowest pressure that can be measured
+ * @pmax: highest pressure that can be measured
+ */
+struct mpr_range_config {
+	const s32 pmin;
+	const s32 pmax;
 };
 
-struct mpr_data {
-	struct i2c_client	*client;
-	struct mutex		lock;		/*
-						 * access to device during read
-						 */
-	u32			pmin;		/* minimal pressure in pascal */
-	u32			pmax;		/* maximal pressure in pascal */
-	enum mpr_func_id	function;	/* transfer function */
-	u32			outmin;		/*
-						 * minimal numerical range raw
-						 * value from sensor
-						 */
-	u32			outmax;		/*
-						 * maximal numerical range raw
-						 * value from sensor
-						 */
-	int                     scale;          /* int part of scale */
-	int                     scale2;         /* nano part of scale */
-	int                     offset;         /* int part of offset */
-	int                     offset2;        /* nano part of offset */
-	struct gpio_desc	*gpiod_reset;	/* reset */
-	int			irq;		/*
-						 * end of conversion irq;
-						 * used to distinguish between
-						 * irq mode and reading in a
-						 * loop until data is ready
-						 */
-	struct completion	completion;	/* handshake from irq to read */
-	struct mpr_chan		chan;		/*
-						 * channel values for buffered
-						 * mode
-						 */
+/* All min max limits have been converted to pascals */
+static const struct mpr_range_config mpr_range_config[MPR_VARIANTS_MAX] = {
+	[MPR0001BA] = { .pmin = 0, .pmax = 100000 },
+	[MPR01_6BA] = { .pmin = 0, .pmax = 160000 },
+	[MPR02_5BA] = { .pmin = 0, .pmax = 250000 },
+	[MPR0060MG] = { .pmin = 0, .pmax =   6000 },
+	[MPR0100MG] = { .pmin = 0, .pmax =  10000 },
+	[MPR0160MG] = { .pmin = 0, .pmax =  16000 },
+	[MPR0250MG] = { .pmin = 0, .pmax =  25000 },
+	[MPR0400MG] = { .pmin = 0, .pmax =  40000 },
+	[MPR0600MG] = { .pmin = 0, .pmax =  60000 },
+	[MPR0001BG] = { .pmin = 0, .pmax = 100000 },
+	[MPR01_6BG] = { .pmin = 0, .pmax = 160000 },
+	[MPR02_5BG] = { .pmin = 0, .pmax = 250000 },
+	[MPR0100KA] = { .pmin = 0, .pmax = 100000 },
+	[MPR0160KA] = { .pmin = 0, .pmax = 160000 },
+	[MPR0250KA] = { .pmin = 0, .pmax = 250000 },
+	[MPR0006KG] = { .pmin = 0, .pmax =   6000 },
+	[MPR0010KG] = { .pmin = 0, .pmax =  10000 },
+	[MPR0016KG] = { .pmin = 0, .pmax =  16000 },
+	[MPR0025KG] = { .pmin = 0, .pmax =  25000 },
+	[MPR0040KG] = { .pmin = 0, .pmax =  40000 },
+	[MPR0060KG] = { .pmin = 0, .pmax =  60000 },
+	[MPR0100KG] = { .pmin = 0, .pmax = 100000 },
+	[MPR0160KG] = { .pmin = 0, .pmax = 160000 },
+	[MPR0250KG] = { .pmin = 0, .pmax = 250000 },
+	[MPR0015PA] = { .pmin = 0, .pmax = 103421 },
+	[MPR0025PA] = { .pmin = 0, .pmax = 172369 },
+	[MPR0030PA] = { .pmin = 0, .pmax = 206843 },
+	[MPR0001PG] = { .pmin = 0, .pmax =   6895 },
+	[MPR0005PG] = { .pmin = 0, .pmax =  34474 },
+	[MPR0015PG] = { .pmin = 0, .pmax = 103421 },
+	[MPR0030PG] = { .pmin = 0, .pmax = 206843 },
+	[MPR0300YG] = { .pmin = 0, .pmax =  39997 }
 };
 
 static const struct iio_chan_spec mpr_channels[] = {
 	{
 		.type = IIO_PRESSURE,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
-					BIT(IIO_CHAN_INFO_SCALE) |
-					BIT(IIO_CHAN_INFO_OFFSET),
+				      BIT(IIO_CHAN_INFO_SCALE) |
+				      BIT(IIO_CHAN_INFO_OFFSET),
 		.scan_index = 0,
 		.scan_type = {
 			.sign = 's',
@@ -153,11 +175,8 @@ static void mpr_reset(struct mpr_data *data)
 }
 
 /**
- * mpr_read_pressure() - Read pressure value from sensor via I2C
+ * mpr_read_conversion() - Read pressure value from sensor
  * @data: Pointer to private data struct.
- * @press: Output value read from sensor.
- *
- * Reading from the sensor by sending and receiving I2C telegrams.
  *
  * If there is an end of conversion (EOC) interrupt registered the function
  * waits for a maximum of one second for the interrupt.
@@ -168,27 +187,19 @@ static void mpr_reset(struct mpr_data *data)
  * * -ETIMEDOUT	- Timeout while waiting for the EOC interrupt or busy flag is
  *		  still set after nloops attempts of reading
  */
-static int mpr_read_pressure(struct mpr_data *data, s32 *press)
+static int mpr_read_conversion(struct mpr_data *data)
 {
-	struct device *dev = &data->client->dev;
+	struct device *dev = data->dev;
 	int ret, i;
-	u8 wdata[] = {0xAA, 0x00, 0x00};
-	s32 status;
 	int nloops = 10;
-	u8 buf[4];
 
 	reinit_completion(&data->completion);
 
-	ret = i2c_master_send(data->client, wdata, sizeof(wdata));
+	ret = data->write_cb(data, MPR_CMD_SYNC, MPR_PKT_SYNC_LEN);
 	if (ret < 0) {
 		dev_err(dev, "error while writing ret: %d\n", ret);
 		return ret;
 	}
-	if (ret != sizeof(wdata)) {
-		dev_err(dev, "received size doesn't fit - ret: %d / %u\n", ret,
-							(u32)sizeof(wdata));
-		return -EIO;
-	}
 
 	if (data->irq > 0) {
 		ret = wait_for_completion_timeout(&data->completion, HZ);
@@ -206,14 +217,14 @@ static int mpr_read_pressure(struct mpr_data *data, s32 *press)
 			 *     quite long
 			 */
 			usleep_range(5000, 10000);
-			status = i2c_smbus_read_byte(data->client);
-			if (status < 0) {
+			ret = data->read_cb(data, MPR_CMD_NOP, 1);
+			if (ret < 0) {
 				dev_err(dev,
 					"error while reading, status: %d\n",
-					status);
-				return status;
+					ret);
+				return ret;
 			}
-			if (!(status & MPR_I2C_BUSY))
+			if (data->buffer[0] == MPR_I2C_POWER)
 				break;
 		}
 		if (i == nloops) {
@@ -222,30 +233,16 @@ static int mpr_read_pressure(struct mpr_data *data, s32 *press)
 		}
 	}
 
-	ret = i2c_master_recv(data->client, buf, sizeof(buf));
-	if (ret < 0) {
-		dev_err(dev, "error in i2c_master_recv ret: %d\n", ret);
+	ret = data->read_cb(data, MPR_CMD_NOP, MPR_PKT_NOP_LEN);
+	if (ret < 0)
 		return ret;
-	}
-	if (ret != sizeof(buf)) {
-		dev_err(dev, "received size doesn't fit - ret: %d / %u\n", ret,
-							(u32)sizeof(buf));
-		return -EIO;
-	}
 
-	if (buf[0] & MPR_I2C_BUSY) {
-		/*
-		 * it should never be the case that status still indicates
-		 * business
-		 */
-		dev_err(dev, "data still not ready: %08x\n", buf[0]);
+	if (data->buffer[0] != MPR_I2C_POWER) {
+		dev_err(data->dev,
+			"unexpected status byte %02x\n", data->buffer[0]);
 		return -ETIMEDOUT;
 	}
 
-	*press = get_unaligned_be24(&buf[1]);
-
-	dev_dbg(dev, "received: %*ph cnt: %d\n", ret, buf, *press);
-
 	return 0;
 }
 
@@ -261,20 +258,22 @@ static irqreturn_t mpr_eoc_handler(int irq, void *p)
 static irqreturn_t mpr_trigger_handler(int irq, void *p)
 {
 	int ret;
+	u32 recvd;
 	struct iio_poll_func *pf = p;
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct mpr_data *data = iio_priv(indio_dev);
 
-	mutex_lock(&data->lock);
-	ret = mpr_read_pressure(data, &data->chan.pres);
+	guard(mutex)(&data->lock);
+	ret = mpr_read_conversion(data);
 	if (ret < 0)
 		goto err;
 
+	recvd = get_unaligned_be32(data->buffer);
+	data->chan.pres = FIELD_GET(MPR_PRESSURE_MASK, recvd);
 	iio_push_to_buffers_with_timestamp(indio_dev, &data->chan,
-						iio_get_time_ns(indio_dev));
+					   iio_get_time_ns(indio_dev));
 
 err:
-	mutex_unlock(&data->lock);
 	iio_trigger_notify_done(indio_dev->trig);
 
 	return IRQ_HANDLED;
@@ -284,28 +283,28 @@ static int mpr_read_raw(struct iio_dev *indio_dev,
 	struct iio_chan_spec const *chan, int *val, int *val2, long mask)
 {
 	int ret;
-	s32 pressure;
 	struct mpr_data *data = iio_priv(indio_dev);
+	u32 recvd;
 
 	if (chan->type != IIO_PRESSURE)
 		return -EINVAL;
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
-		mutex_lock(&data->lock);
-		ret = mpr_read_pressure(data, &pressure);
-		mutex_unlock(&data->lock);
+		ret = mpr_read_conversion(data);
 		if (ret < 0)
 			return ret;
-		*val = pressure;
+
+		recvd = get_unaligned_be32(data->buffer);
+		*val = FIELD_GET(MPR_PRESSURE_MASK, recvd);
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SCALE:
 		*val = data->scale;
-		*val2 = data->scale2;
+		*val2 = data->scale_dec;
 		return IIO_VAL_INT_PLUS_NANO;
 	case IIO_CHAN_INFO_OFFSET:
 		*val = data->offset;
-		*val2 = data->offset2;
+		*val2 = data->offset_dec;
 		return IIO_VAL_INT_PLUS_NANO;
 	default:
 		return -EINVAL;
@@ -316,25 +315,25 @@ static const struct iio_info mpr_info = {
 	.read_raw = &mpr_read_raw,
 };
 
-static int mpr_probe(struct i2c_client *client)
+int mpr_common_probe(struct device *dev, mpr_xfer_fn read, mpr_xfer_fn write,
+		     int irq)
 {
 	int ret;
 	struct mpr_data *data;
 	struct iio_dev *indio_dev;
-	struct device *dev = &client->dev;
+	const char *triplet;
 	s64 scale, offset;
-
-	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE))
-		return dev_err_probe(dev, -EOPNOTSUPP,
-					"I2C functionality not supported\n");
+	u32 func;
 
 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
 	if (!indio_dev)
-		return dev_err_probe(dev, -ENOMEM, "couldn't get iio_dev\n");
+		return -ENOMEM;
 
 	data = iio_priv(indio_dev);
-	data->client = client;
-	data->irq = client->irq;
+	data->dev = dev;
+	data->read_cb = read;
+	data->write_cb = write;
+	data->irq = irq;
 
 	mutex_init(&data->lock);
 	init_completion(&data->completion);
@@ -345,64 +344,85 @@ static int mpr_probe(struct i2c_client *client)
 	indio_dev->num_channels = ARRAY_SIZE(mpr_channels);
 	indio_dev->modes = INDIO_DIRECT_MODE;
 
-	ret = devm_regulator_get_enable(dev, "vdd");
+#ifdef TESTING_NOT_PART_OF_PRODUCTION_VERSION
+	/* when loaded as i2c device we need to use default values */
+	dev_notice(dev, "firmware node not found; using defaults\n");
+	data->pmin = 0;
+	data->pmax = 172369; /* 25 psi */
+	data->function = MPR_FUNCTION_A;
+#else
+	ret = device_property_read_u32(dev,
+			       "honeywell,transfer-function", &func);
 	if (ret)
 		return dev_err_probe(dev, ret,
-				"can't get and enable vdd supply\n");
+			    "honeywell,transfer-function could not be read\n");
+	data->function = func - 1;
+	if (data->function > MPR_FUNCTION_C)
+		return dev_err_probe(dev, -EINVAL,
+				     "honeywell,transfer-function %d invalid\n",
+				     data->function);
+
+	ret = device_property_read_string(dev, "honeywell,pressure-triplet",
+					  &triplet);
+	if (ret)
+		return dev_err_probe(dev, ret,
+			     "honeywell,pressure-triplet could not be read\n");
 
-	if (dev_fwnode(dev)) {
+	if (str_has_prefix(triplet, "NA")) {
 		ret = device_property_read_u32(dev, "honeywell,pmin-pascal",
-								&data->pmin);
+					       &data->pmin);
 		if (ret)
 			return dev_err_probe(dev, ret,
-				"honeywell,pmin-pascal could not be read\n");
+				  "honeywell,pmin-pascal could not be read\n");
+
 		ret = device_property_read_u32(dev, "honeywell,pmax-pascal",
-								&data->pmax);
-		if (ret)
-			return dev_err_probe(dev, ret,
-				"honeywell,pmax-pascal could not be read\n");
-		ret = device_property_read_u32(dev,
-				"honeywell,transfer-function", &data->function);
+					       &data->pmax);
 		if (ret)
 			return dev_err_probe(dev, ret,
-				"honeywell,transfer-function could not be read\n");
-		if (data->function > MPR_FUNCTION_C)
-			return dev_err_probe(dev, -EINVAL,
-				"honeywell,transfer-function %d invalid\n",
-								data->function);
+				  "honeywell,pmax-pascal could not be read\n");
 	} else {
-		/* when loaded as i2c device we need to use default values */
-		dev_notice(dev, "firmware node not found; using defaults\n");
-		data->pmin = 0;
-		data->pmax = 172369; /* 25 psi */
-		data->function = MPR_FUNCTION_A;
+		ret = device_property_match_property_string(dev,
+						  "honeywell,pressure-triplet",
+						  mpr_triplet_variants,
+						  MPR_VARIANTS_MAX);
+		if (ret < 0)
+			return dev_err_probe(dev, -EINVAL,
+				    "honeywell,pressure-triplet is invalid\n");
+
+		data->pmin = mpr_range_config[ret].pmin;
+		data->pmax = mpr_range_config[ret].pmax;
 	}
+#endif
+
+	if (data->pmin >= data->pmax)
+		return dev_err_probe(dev, -EINVAL,
+				     "pressure limits are invalid\n");
+
+	ret = devm_regulator_get_enable(dev, "vdd");
+	if (ret)
+		return dev_err_probe(dev, ret, "can't get vdd supply\n");
 
 	data->outmin = mpr_func_spec[data->function].output_min;
 	data->outmax = mpr_func_spec[data->function].output_max;
 
 	/* use 64 bit calculation for preserving a reasonable precision */
 	scale = div_s64(((s64)(data->pmax - data->pmin)) * NANO,
-						data->outmax - data->outmin);
-	data->scale = div_s64_rem(scale, NANO, &data->scale2);
-	/*
-	 * multiply with NANO before dividing by scale and later divide by NANO
-	 * again.
-	 */
+			data->outmax - data->outmin);
+	data->scale = div_s64_rem(scale, NANO, &data->scale_dec);
 	offset = ((-1LL) * (s64)data->outmin) * NANO -
-			div_s64(div_s64((s64)data->pmin * NANO, scale), NANO);
-	data->offset = div_s64_rem(offset, NANO, &data->offset2);
+		 div_s64(div_s64((s64)data->pmin * NANO, scale), NANO);
+	data->offset = div_s64_rem(offset, NANO, &data->offset_dec);
 
 	if (data->irq > 0) {
 		ret = devm_request_irq(dev, data->irq, mpr_eoc_handler,
-				IRQF_TRIGGER_RISING, client->name, data);
+				IRQF_TRIGGER_RISING, dev_name(dev), data);
 		if (ret)
 			return dev_err_probe(dev, ret,
 				"request irq %d failed\n", data->irq);
 	}
 
 	data->gpiod_reset = devm_gpiod_get_optional(dev, "reset",
-							GPIOD_OUT_HIGH);
+						    GPIOD_OUT_HIGH);
 	if (IS_ERR(data->gpiod_reset))
 		return dev_err_probe(dev, PTR_ERR(data->gpiod_reset),
 						"request reset-gpio failed\n");
@@ -410,41 +430,20 @@ static int mpr_probe(struct i2c_client *client)
 	mpr_reset(data);
 
 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
-						mpr_trigger_handler, NULL);
+					      mpr_trigger_handler, NULL);
 	if (ret)
 		return dev_err_probe(dev, ret,
-					"iio triggered buffer setup failed\n");
+				     "iio triggered buffer setup failed\n");
 
 	ret = devm_iio_device_register(dev, indio_dev);
 	if (ret)
 		return dev_err_probe(dev, ret,
-					"unable to register iio device\n");
+				     "unable to register iio device\n");
 
 	return 0;
 }
-
-static const struct of_device_id mpr_matches[] = {
-	{ .compatible = "honeywell,mprls0025pa" },
-	{ }
-};
-MODULE_DEVICE_TABLE(of, mpr_matches);
-
-static const struct i2c_device_id mpr_id[] = {
-	{ "mprls0025pa" },
-	{ }
-};
-MODULE_DEVICE_TABLE(i2c, mpr_id);
-
-static struct i2c_driver mpr_driver = {
-	.probe		= mpr_probe,
-	.id_table	= mpr_id,
-	.driver		= {
-		.name		= "mprls0025pa",
-		.of_match_table = mpr_matches,
-	},
-};
-module_i2c_driver(mpr_driver);
+EXPORT_SYMBOL_NS(mpr_common_probe, IIO_HONEYWELL_MPRLS0025PA);
 
 MODULE_AUTHOR("Andreas Klinger <ak@it-klinger.de>");
-MODULE_DESCRIPTION("Honeywell MPRLS0025PA I2C driver");
+MODULE_DESCRIPTION("Honeywell MPR pressure sensor core driver");
 MODULE_LICENSE("GPL");
diff --git a/drivers/iio/pressure/mprls0025pa.h b/drivers/iio/pressure/mprls0025pa.h
new file mode 100644
index 000000000000..b47fc26a309d
--- /dev/null
+++ b/drivers/iio/pressure/mprls0025pa.h
@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * MPRLS0025PA - Honeywell MicroPressure pressure sensor series driver
+ *
+ * Copyright (c) Andreas Klinger <ak@it-klinger.de>
+ *
+ * Data sheet:
+ *  https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
+ */
+
+#ifndef _MPRLS0025PA_H
+#define _MPRLS0025PA_H
+
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/stddef.h>
+#include <linux/types.h>
+
+#define MPR_MEASUREMENT_RD_SIZE 4
+#define MPR_CMD_NOP      0xf0
+#define MPR_CMD_SYNC     0xaa
+#define MPR_PKT_NOP_LEN  MPR_MEASUREMENT_RD_SIZE
+#define MPR_PKT_SYNC_LEN 3
+
+/* bits in i2c status byte */
+#define MPR_I2C_POWER	BIT(6)	/* device is powered */
+#define MPR_I2C_BUSY	BIT(5)	/* device is busy */
+#define MPR_I2C_MEMORY	BIT(2)	/* integrity test passed */
+#define MPR_I2C_MATH	BIT(0)	/* internal math saturation */
+
+struct device;
+
+struct iio_chan_spec;
+struct iio_dev;
+
+struct mpr_data;
+
+typedef int (*mpr_xfer_fn)(struct mpr_data *, const u8, const u8);
+
+enum mpr_func_id {
+	MPR_FUNCTION_A,
+	MPR_FUNCTION_B,
+	MPR_FUNCTION_C,
+};
+
+/**
+ * struct mpr_chan
+ * @pres: pressure value
+ * @ts: timestamp
+ */
+struct mpr_chan {
+	s32 pres;
+	s64 ts;
+};
+
+/**
+ * struct mpr_data
+ * @dev: current device structure
+ * @read_cb: function that implements the sensor reads
+ * @write_cb: function that implements the sensor writes
+ * @pmin: minimal pressure in pascal
+ * @pmax: maximal pressure in pascal
+ * @function: transfer function
+ * @outmin: minimum raw pressure in counts (based on transfer function)
+ * @outmax: maximum raw pressure in counts (based on transfer function)
+ * @scale: pressure scale
+ * @scale2: pressure scale, decimal places
+ * @offset: pressure offset
+ * @offset2: pressure offset, decimal places
+ * @gpiod_reset: reset
+ * @irq: end of conversion irq. used to distinguish between irq mode and
+ *       reading in a loop until data is ready
+ * @completion: handshake from irq to read
+ * @chan: channel values for buffered mode
+ * @buffer: raw conversion data
+ */
+struct mpr_data {
+	struct device		*dev;
+	mpr_xfer_fn		read_cb;
+	mpr_xfer_fn		write_cb;
+	struct mutex		lock;
+	u32			pmin;
+	u32			pmax;
+	enum mpr_func_id	function;
+	u32			outmin;
+	u32			outmax;
+	int			scale;
+	int			scale_dec;
+	int			offset;
+	int			offset_dec;
+	struct gpio_desc	*gpiod_reset;
+	int			irq;
+	struct completion	completion;
+	struct mpr_chan		chan;
+	u8			buffer[MPR_MEASUREMENT_RD_SIZE] __aligned(IIO_DMA_MINALIGN);
+};
+
+int mpr_common_probe(struct device *dev, mpr_xfer_fn read, mpr_xfer_fn write,
+		     int irq);
+
+#endif
diff --git a/drivers/iio/pressure/mprls0025pa_i2c.c b/drivers/iio/pressure/mprls0025pa_i2c.c
new file mode 100644
index 000000000000..2651f1e1bc08
--- /dev/null
+++ b/drivers/iio/pressure/mprls0025pa_i2c.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * MPRLS0025PA - Honeywell MicroPressure pressure sensor series driver
+ *
+ * Copyright (c) Andreas Klinger <ak@it-klinger.de>
+ *
+ * Data sheet:
+ *  https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
+ */
+
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+
+#include <linux/iio/iio.h>
+
+#include "mprls0025pa.h"
+
+static int mpr_i2c_read(struct mpr_data *data, const u8 unused, const u8 pkt_len)
+{
+	struct i2c_client *client = to_i2c_client(data->dev);
+
+	if (pkt_len > MPR_MEASUREMENT_RD_SIZE)
+		return -EOVERFLOW;
+
+	memset(data->buffer, 0, MPR_MEASUREMENT_RD_SIZE);
+	return i2c_master_recv(client, data->buffer, pkt_len);
+}
+
+static int mpr_i2c_write(struct mpr_data *data, const u8 cmd, const u8 unused)
+{
+	struct i2c_client *client = to_i2c_client(data->dev);
+	u8 wdata[MPR_PKT_SYNC_LEN];
+
+	memset(wdata, 0, sizeof(wdata));
+	wdata[0] = cmd;
+
+	return i2c_master_send(client, wdata, MPR_PKT_SYNC_LEN);
+}
+
+static int mpr_i2c_probe(struct i2c_client *client)
+{
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE))
+		return -EOPNOTSUPP;
+
+	return mpr_common_probe(&client->dev, mpr_i2c_read, mpr_i2c_write,
+				client->irq);
+}
+
+static const struct of_device_id mpr_i2c_match[] = {
+	{ .compatible = "honeywell,mprls0025pa" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, mpr_i2c_match);
+
+static const struct i2c_device_id mpr_i2c_id[] = {
+	{ "mprls0025pa" },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, mpr_i2c_id);
+
+static struct i2c_driver mpr_i2c_driver = {
+	.probe = mpr_i2c_probe,
+	.id_table = mpr_i2c_id,
+	.driver = {
+		.name = "mprls0025pa",
+		.of_match_table = mpr_i2c_match,
+	},
+};
+module_i2c_driver(mpr_i2c_driver);
+
+MODULE_AUTHOR("Andreas Klinger <ak@it-klinger.de>");
+MODULE_DESCRIPTION("Honeywell MPR pressure sensor i2c driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(IIO_HONEYWELL_MPRLS0025PA);
diff --git a/drivers/iio/pressure/mprls0025pa_spi.c b/drivers/iio/pressure/mprls0025pa_spi.c
new file mode 100644
index 000000000000..41cd4bad02f7
--- /dev/null
+++ b/drivers/iio/pressure/mprls0025pa_spi.c
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * MPRLS0025PA - Honeywell MicroPressure MPR series SPI sensor driver
+ *
+ * Copyright (c) 2024 Petre Rodan <petre.rodan@subdimension.ro>
+ *
+ * Data sheet:
+ *  https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
+ */
+
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/stddef.h>
+
+#include <linux/iio/iio.h>
+
+#include "mprls0025pa.h"
+
+static int mpr_spi_xfer(struct mpr_data *data, const u8 cmd, const u8 pkt_len)
+{
+	struct spi_device *spi = to_spi_device(data->dev);
+	u8 tx_buf[MPR_MEASUREMENT_RD_SIZE];
+	struct spi_transfer xfer;
+
+	if (pkt_len > MPR_MEASUREMENT_RD_SIZE)
+		return -EOVERFLOW;
+
+	tx_buf[0] = cmd;
+	xfer.tx_buf = tx_buf;
+	xfer.rx_buf = data->buffer;
+	xfer.len = pkt_len;
+
+	return spi_sync_transfer(spi, &xfer, 1);
+}
+
+static int mpr_spi_probe(struct spi_device *spi)
+{
+	return mpr_common_probe(&spi->dev, mpr_spi_xfer, mpr_spi_xfer, spi->irq);
+}
+
+static const struct of_device_id mpr_spi_match[] = {
+	{ .compatible = "honeywell,mprls0025pa" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, mpr_spi_match);
+
+static const struct spi_device_id mpr_spi_id[] = {
+	{ "mprls0025pa" },
+	{}
+};
+MODULE_DEVICE_TABLE(spi, mpr_spi_id);
+
+static struct spi_driver mpr_spi_driver = {
+	.driver = {
+		.name = "mprls0025pa",
+		.of_match_table = mpr_spi_match,
+	},
+	.probe = mpr_spi_probe,
+	.id_table = mpr_spi_id,
+};
+module_spi_driver(mpr_spi_driver);
+
+MODULE_AUTHOR("Petre Rodan <petre.rodan@subdimension.ro>");
+MODULE_DESCRIPTION("Honeywell MPR pressure sensor spi driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(IIO_HONEYWELL_MPRLS0025PA);
-- 
2.41.0

Re: [PATCH 2/2] iio: pressure: change driver for Honeywell MPR series

[Andy Shevchenko]

On Tue, Dec 19, 2023 at 03:02:21PM +0200, Petre Rodan wrote:
> ChangeLog
>  - rewrite flow so that driver can use either i2c or spi as communication bus
>  - add spi driver (tested on MPRLS0015PA0000SA)
>  - add pressure-triplet property that automatically sets pmin, pmax
>  - fix transfer-function enum typo based on previous review [1]
>  - fix interrupt example in binding file (FALLING -> RISING edge)
>  - indentation changes based on previous code reviews
>  - renamed mpr_read_pressure to mpr_read_conversion since the sensor is
>    supposed to also provide temperature measuremets
>    (but I think mine is broken since the raw temperature value is always
>    0x800000 - so temp reading not currently implemented)

Changelog...

> I've been told in the past that the use of mutexes is redundant in these cases
> so please assess if the guard() from the driver code is required or should be
> removed.

A comment...

> patch uses device_property_match_property_string() from the 'togreg' branch

Another comment...

> [1]: https://lore.kernel.org/lkml/20231116-grudge-hankering-b7a71d831b93@squawk/T/

Some Link: (should it be a tag?)...

Where is the commit message? Or is this just an intermediate change
to show what will be in the next version? I'm confused.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 2/2] iio: pressure: change driver for Honeywell MPR series

[Petre Rodan]

[-- Attachment #1: Type: text/plain, Size: 1947 bytes --]

On Tue, Dec 19, 2023 at 05:41:25PM +0200, Andy Shevchenko wrote:
> On Tue, Dec 19, 2023 at 03:02:21PM +0200, Petre Rodan wrote:
> > ChangeLog
> >  - rewrite flow so that driver can use either i2c or spi as communication bus
> >  - add spi driver (tested on MPRLS0015PA0000SA)
> >  - add pressure-triplet property that automatically sets pmin, pmax
> >  - fix transfer-function enum typo based on previous review [1]
> >  - fix interrupt example in binding file (FALLING -> RISING edge)
> >  - indentation changes based on previous code reviews
> >  - renamed mpr_read_pressure to mpr_read_conversion since the sensor is
> >    supposed to also provide temperature measuremets
> >    (but I think mine is broken since the raw temperature value is always
> >    0x800000 - so temp reading not currently implemented)
> 
> Changelog...
> 
> > I've been told in the past that the use of mutexes is redundant in these cases
> > so please assess if the guard() from the driver code is required or should be
> > removed.
> 
> A comment...
> 
> > patch uses device_property_match_property_string() from the 'togreg' branch
> 
> Another comment...
> 
> > [1]: https://lore.kernel.org/lkml/20231116-grudge-hankering-b7a71d831b93@squawk/T/
> 
> Some Link: (should it be a tag?)...

it's a reference link that was pointed to within the text above.
it emulates `lynx --dump foo.html`. designed for human reading, sorry if it
broke some parsing script.

> Where is the commit message? Or is this just an intermediate change
> to show what will be in the next version? I'm confused.

the commit message is between the end of the mail header and before the actual
patch. the two comments were also placed for human interaction.
they will be removed later on when we get close to acceptance and someone
replies to them. and yes, the entire patch is full and self-contained in these
3 messages.

very best regards,
peter

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

Re: [PATCH 2/2] iio: pressure: change driver for Honeywell MPR series

[Jonathan Cameron]

On Tue, 19 Dec 2023 15:02:21 +0200
Petre Rodan <petre.rodan@subdimension.ro> wrote:

> ChangeLog
>  - rewrite flow so that driver can use either i2c or spi as communication bus
>  - add spi driver (tested on MPRLS0015PA0000SA)
>  - add pressure-triplet property that automatically sets pmin, pmax
>  - fix transfer-function enum typo based on previous review [1]
>  - fix interrupt example in binding file (FALLING -> RISING edge)
>  - indentation changes based on previous code reviews
>  - renamed mpr_read_pressure to mpr_read_conversion since the sensor is
>    supposed to also provide temperature measuremets
>    (but I think mine is broken since the raw temperature value is always
>    0x800000 - so temp reading not currently implemented)

This is a lot of different things.  You need to break them up into
individual patches in the order.

1. Fixes (to enable easy backports)
2. Cleanup (usually better to do these ahead of new stuff)
3. Refactors to enable each new item, then for each one
4. New stuff such as the spi support and the new properties etc.

Also good to spell check your commit messages as at least one typo above.


I took a quick glance - but it's much more challenging to review a mixed
up patch like this than a series of well defined changes so its just
a few things I happened to notice rather than a proper review.

thanks,

Jonathan
> 
> I've been told in the past that the use of mutexes is redundant in these cases
> so please assess if the guard() from the driver code is required or should be
> removed.
> 
> patch uses device_property_match_property_string() from the 'togreg' branch
> 
> [1]: https://lore.kernel.org/lkml/20231116-grudge-hankering-b7a71d831b93@squawk/T/
> Datasheet:
> https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
> Signed-off-by: Petre Rodan <petre.rodan@subdimension.ro>

...

> diff --git a/drivers/iio/pressure/mprls0025pa.c b/drivers/iio/pressure/mprls0025pa.c
> index 30fb2de36821..4a999bf73964 100644
> --- a/drivers/iio/pressure/mprls0025pa.c
> +++ b/drivers/iio/pressure/mprls0025pa.c
> @@ -5,17 +5,14 @@


>  	mutex_init(&data->lock);
>  	init_completion(&data->completion);
> @@ -345,64 +344,85 @@ static int mpr_probe(struct i2c_client *client)
>  	indio_dev->num_channels = ARRAY_SIZE(mpr_channels);
>  	indio_dev->modes = INDIO_DIRECT_MODE;
>  
> -	ret = devm_regulator_get_enable(dev, "vdd");
> +#ifdef TESTING_NOT_PART_OF_PRODUCTION_VERSION

Looks like you didn't clear this out...

> +	/* when loaded as i2c device we need to use default values */
> +	dev_notice(dev, "firmware node not found; using defaults\n");
> +	data->pmin = 0;
> +	data->pmax = 172369; /* 25 psi */
> +	data->function = MPR_FUNCTION_A;
> +#else
> +	ret = device_property_read_u32(dev,
> +			       "honeywell,transfer-function", &func);
>  	if (ret)
>  		return dev_err_probe(dev, ret,
> -				"can't get and enable vdd supply\n");
> +			    "honeywell,transfer-function could not be read\n");
> +	data->function = func - 1;
> +	if (data->function > MPR_FUNCTION_C)
> +		return dev_err_probe(dev, -EINVAL,
> +				     "honeywell,transfer-function %d invalid\n",
> +				     data->function);
> +
> +	ret = device_property_read_string(dev, "honeywell,pressure-triplet",
> +					  &triplet);
> +	if (ret)
> +		return dev_err_probe(dev, ret,
> +			     "honeywell,pressure-triplet could not be read\n");
>  
> -	if (dev_fwnode(dev)) {
> +	if (str_has_prefix(triplet, "NA")) {
>  		ret = device_property_read_u32(dev, "honeywell,pmin-pascal",
> -								&data->pmin);
> +					       &data->pmin);
>  		if (ret)
>  			return dev_err_probe(dev, ret,
> -				"honeywell,pmin-pascal could not be read\n");
> +				  "honeywell,pmin-pascal could not be read\n");
> +
>  		ret = device_property_read_u32(dev, "honeywell,pmax-pascal",
> -								&data->pmax);
> -		if (ret)
> -			return dev_err_probe(dev, ret,
> -				"honeywell,pmax-pascal could not be read\n");
> -		ret = device_property_read_u32(dev,
> -				"honeywell,transfer-function", &data->function);
> +					       &data->pmax);
>  		if (ret)
>  			return dev_err_probe(dev, ret,
> -				"honeywell,transfer-function could not be read\n");
> -		if (data->function > MPR_FUNCTION_C)
> -			return dev_err_probe(dev, -EINVAL,
> -				"honeywell,transfer-function %d invalid\n",
> -								data->function);
> +				  "honeywell,pmax-pascal could not be read\n");
>  	} else {
> -		/* when loaded as i2c device we need to use default values */
> -		dev_notice(dev, "firmware node not found; using defaults\n");
> -		data->pmin = 0;
> -		data->pmax = 172369; /* 25 psi */
> -		data->function = MPR_FUNCTION_A;
> +		ret = device_property_match_property_string(dev,
> +						  "honeywell,pressure-triplet",
> +						  mpr_triplet_variants,
> +						  MPR_VARIANTS_MAX);
> +		if (ret < 0)
> +			return dev_err_probe(dev, -EINVAL,
> +				    "honeywell,pressure-triplet is invalid\n");
> +
> +		data->pmin = mpr_range_config[ret].pmin;
> +		data->pmax = mpr_range_config[ret].pmax;
>  	}
> +#endif
...

>  		if (ret)
>  			return dev_err_probe(dev, ret,
>  				"request irq %d failed\n", data->irq);
>  	}
>  
>  	data->gpiod_reset = devm_gpiod_get_optional(dev, "reset",
> -							GPIOD_OUT_HIGH);
> +						    GPIOD_OUT_HIGH);
>  	if (IS_ERR(data->gpiod_reset))
>  		return dev_err_probe(dev, PTR_ERR(data->gpiod_reset),
>  						"request reset-gpio failed\n");
> @@ -410,41 +430,20 @@ static int mpr_probe(struct i2c_client *client)
>  	mpr_reset(data);
>  
>  	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
> -						mpr_trigger_handler, NULL);
> +					      mpr_trigger_handler, NULL);
>  	if (ret)
>  		return dev_err_probe(dev, ret,
> -					"iio triggered buffer setup failed\n");
> +				     "iio triggered buffer setup failed\n");
>  
>  	ret = devm_iio_device_register(dev, indio_dev);
>  	if (ret)
>  		return dev_err_probe(dev, ret,
> -					"unable to register iio device\n");
> +				     "unable to register iio device\n");
>  
Any white space changes need to be in their own patch so they don't add noise to a patch
doing anything else.



> diff --git a/drivers/iio/pressure/mprls0025pa.h b/drivers/iio/pressure/mprls0025pa.h
> new file mode 100644
> index 000000000000..b47fc26a309d
> --- /dev/null
> +++ b/drivers/iio/pressure/mprls0025pa.h
> @@ -0,0 +1,103 @@
> +/**
> + * struct mpr_data
> + * @dev: current device structure
> + * @read_cb: function that implements the sensor reads
> + * @write_cb: function that implements the sensor writes
> + * @pmin: minimal pressure in pascal
> + * @pmax: maximal pressure in pascal
> + * @function: transfer function
> + * @outmin: minimum raw pressure in counts (based on transfer function)
> + * @outmax: maximum raw pressure in counts (based on transfer function)
> + * @scale: pressure scale
> + * @scale2: pressure scale, decimal places
> + * @offset: pressure offset
> + * @offset2: pressure offset, decimal places
> + * @gpiod_reset: reset
> + * @irq: end of conversion irq. used to distinguish between irq mode and
> + *       reading in a loop until data is ready
> + * @completion: handshake from irq to read
> + * @chan: channel values for buffered mode
> + * @buffer: raw conversion data
> + */
> +struct mpr_data {
> +	struct device		*dev;
> +	mpr_xfer_fn		read_cb;
> +	mpr_xfer_fn		write_cb;
> +	struct mutex		lock;
> +	u32			pmin;
> +	u32			pmax;
> +	enum mpr_func_id	function;
> +	u32			outmin;
> +	u32			outmax;
> +	int			scale;
> +	int			scale_dec;
> +	int			offset;
> +	int			offset_dec;
Docs don't match.
> +	struct gpio_desc	*gpiod_reset;
> +	int			irq;
> +	struct completion	completion;
> +	struct mpr_chan		chan;
> +	u8			buffer[MPR_MEASUREMENT_RD_SIZE] __aligned(IIO_DMA_MINALIGN);
> +};
> +

...

> diff --git a/drivers/iio/pressure/mprls0025pa_spi.c b/drivers/iio/pressure/mprls0025pa_spi.c
> new file mode 100644
> index 000000000000..41cd4bad02f7
> --- /dev/null
> +++ b/drivers/iio/pressure/mprls0025pa_spi.c
> @@ -0,0 +1,67 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * MPRLS0025PA - Honeywell MicroPressure MPR series SPI sensor driver
> + *
> + * Copyright (c) 2024 Petre Rodan <petre.rodan@subdimension.ro>
> + *
> + * Data sheet:
> + *  https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/products/sensors/pressure-sensors/board-mount-pressure-sensors/micropressure-mpr-series/documents/sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf
> + */
> +
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/spi/spi.h>
> +#include <linux/stddef.h>
> +
> +#include <linux/iio/iio.h>
> +
> +#include "mprls0025pa.h"
> +
> +static int mpr_spi_xfer(struct mpr_data *data, const u8 cmd, const u8 pkt_len)
> +{
> +	struct spi_device *spi = to_spi_device(data->dev);
> +	u8 tx_buf[MPR_MEASUREMENT_RD_SIZE];
> +	struct spi_transfer xfer;
> +
> +	if (pkt_len > MPR_MEASUREMENT_RD_SIZE)
> +		return -EOVERFLOW;
> +
> +	tx_buf[0] = cmd;
> +	xfer.tx_buf = tx_buf;
> +	xfer.rx_buf = data->buffer;
> +	xfer.len = pkt_len;
> +
> +	return spi_sync_transfer(spi, &xfer, 1);

Fairly sure that requires dma safe buffers which tx_buf is not.

> +}