diff mbox series

[v2,2/2] iio:temperature:max31856:Add device tree bind info

Message ID 1539275890-38141-2-git-send-email-matthew.weber@rockwellcollins.com (mailing list archive)
State New, archived
Headers show
Series [v2,1/2] iio:temperature: Add MAX31856 thermocouple support | expand

Commit Message

Matt Weber Oct. 11, 2018, 4:38 p.m. UTC 
From: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>

This patch added device tree binding info for MAX31856 driver.

Signed-off-by: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>
Signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com>
---
Changes v1 -> v2
[Matt
 - Removed comment block and added possibilities of
   thermocouple type in device tree binding doc.

---
 .../bindings/iio/temperature/max31856.txt          | 32 ++++++++++++++++++++++
 MAINTAINERS                                        |  1 +
 2 files changed, 33 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/temperature/max31856.txt

Comments

Jonathan Cameron Oct. 13, 2018, 1:54 p.m. UTC | #1 
On Thu, 11 Oct 2018 11:38:10 -0500
Matt Weber <matthew.weber@rockwellcollins.com> wrote:

> From: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>
> 
> This patch added device tree binding info for MAX31856 driver.
> 
> Signed-off-by: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>
> Signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com>
Device tree bindings should be cc'd to the devicetree list and maintainers.

Thanks,

Jonathan

> ---
> Changes v1 -> v2
> [Matt
>  - Removed comment block and added possibilities of
>    thermocouple type in device tree binding doc.
> 
> ---
>  .../bindings/iio/temperature/max31856.txt          | 32 ++++++++++++++++++++++
>  MAINTAINERS                                        |  1 +
>  2 files changed, 33 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/temperature/max31856.txt
> 
> diff --git a/Documentation/devicetree/bindings/iio/temperature/max31856.txt b/Documentation/devicetree/bindings/iio/temperature/max31856.txt
> new file mode 100644
> index 0000000..e1def9f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/temperature/max31856.txt
> @@ -0,0 +1,32 @@
> +Maxim MAX31856 thermocouple support
> +
> +https://datasheets.maximintegrated.com/en/ds/MAX31856.pdf
> +
> +Required properties:
> +	- compatible: must be "max31856"
> +	- reg: SPI chip select number for the device
> +	- spi-max-frequency: As per datasheet max. supported freq is 5000000
> +	- spi-cpha: must be defined for max31856 to enable SPI mode 1
> +	- type: Type of thermocouple (By default is K-Type)
> +		0x00 : TYPE_B
> +		0x01 : TYPE_E
> +		0x02 : TYPE_J
> +		0x03 : TYPE_K (default)
> +		0x04 : TYPE_N
> +		0x05 : TYPE_R
> +		0x06 : TYPE_S
> +		0x07 : TYPE_T
> +
> +	Refer to spi/spi-bus.txt for generic SPI slave bindings.
> +
> +Optional properties:
> +	- one-shot: Enable one-shot Conversion mode (By default mode is auto)

Why is this something that should be in devicetree rather than controlled
in the driver in response to some userspace interaction?


> +
> + Example:
> +	max31856@0 {
> +		compatible = "max31856";
> +		reg = <0>;
> +		spi-max-frequency = <5000000>;
> +		spi-cpha;
> +		type = <0x03>;
> +	};
> diff --git a/MAINTAINERS b/MAINTAINERS
> index dd9a83d..6482ae8 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -7161,6 +7161,7 @@ MAX31856 IIO DRIVER
>  M:	Matthew Weber <matthew.weber@rockwellcollins.com>
>  S:	Maintained
>  F:	drivers/iio/temperature/max31856.c
> +F:	Documentation/devicetree/bindings/iio/temperature/max31856.txt
>  
>  IIO UNIT CONVERTER
>  M:	Peter Rosin <peda@axentia.se>
Paresh Chaudhary Oct. 16, 2018, 10:16 p.m. UTC | #2 
Hi Jonathan,

Please find my comment inline.

Thanks,
Paresh

On Sat, Oct 13, 2018 at 8:54 AM Jonathan Cameron <jic23@kernel.org> wrote:
>
> On Thu, 11 Oct 2018 11:38:10 -0500
> Matt Weber <matthew.weber@rockwellcollins.com> wrote:
>
> > From: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>
> >
> > This patch added device tree binding info for MAX31856 driver.
> >
> > Signed-off-by: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>
> > Signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com>
> Device tree bindings should be cc'd to the devicetree list and maintainers.
>
> Thanks,
>
> Jonathan
>
> > ---
> > Changes v1 -> v2
> > [Matt
> >  - Removed comment block and added possibilities of
> >    thermocouple type in device tree binding doc.
> >
> > ---
> >  .../bindings/iio/temperature/max31856.txt          | 32 ++++++++++++++++++++++
> >  MAINTAINERS                                        |  1 +
> >  2 files changed, 33 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/iio/temperature/max31856.txt
> >
> > diff --git a/Documentation/devicetree/bindings/iio/temperature/max31856.txt b/Documentation/devicetree/bindings/iio/temperature/max31856.txt
> > new file mode 100644
> > index 0000000..e1def9f
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/iio/temperature/max31856.txt
> > @@ -0,0 +1,32 @@
> > +Maxim MAX31856 thermocouple support
> > +
> > +https://datasheets.maximintegrated.com/en/ds/MAX31856.pdf
> > +
> > +Required properties:
> > +     - compatible: must be "max31856"
> > +     - reg: SPI chip select number for the device
> > +     - spi-max-frequency: As per datasheet max. supported freq is 5000000
> > +     - spi-cpha: must be defined for max31856 to enable SPI mode 1
> > +     - type: Type of thermocouple (By default is K-Type)
> > +             0x00 : TYPE_B
> > +             0x01 : TYPE_E
> > +             0x02 : TYPE_J
> > +             0x03 : TYPE_K (default)
> > +             0x04 : TYPE_N
> > +             0x05 : TYPE_R
> > +             0x06 : TYPE_S
> > +             0x07 : TYPE_T
> > +
> > +     Refer to spi/spi-bus.txt for generic SPI slave bindings.
> > +
> > +Optional properties:
> > +     - one-shot: Enable one-shot Conversion mode (By default mode is auto)
>
> Why is this something that should be in devicetree rather than controlled
> in the driver in response to some userspace interaction?
>
>
There is no specific reason. This is just providing info to the driver
so the driver can configure chip while probe for specified mode.
I understand your concern but as of now, the driver does not have
support to decide mode based on userspace interaction. We will work on
that when we reopen for enhancement (e.g threshold for temp. range)
> > +
> > + Example:
> > +     max31856@0 {
> > +             compatible = "max31856";
> > +             reg = <0>;
> > +             spi-max-frequency = <5000000>;
> > +             spi-cpha;
> > +             type = <0x03>;
> > +     };
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index dd9a83d..6482ae8 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -7161,6 +7161,7 @@ MAX31856 IIO DRIVER
> >  M:   Matthew Weber <matthew.weber@rockwellcollins.com>
> >  S:   Maintained
> >  F:   drivers/iio/temperature/max31856.c
> > +F:   Documentation/devicetree/bindings/iio/temperature/max31856.txt
> >
> >  IIO UNIT CONVERTER
> >  M:   Peter Rosin <peda@axentia.se>
>
Jonathan Cameron Oct. 21, 2018, 2:19 p.m. UTC | #3 
On Tue, 16 Oct 2018 17:16:15 -0500
Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com> wrote:

> Hi Jonathan,
> 
> Please find my comment inline.
> 
> Thanks,
> Paresh
> 
> On Sat, Oct 13, 2018 at 8:54 AM Jonathan Cameron <jic23@kernel.org> wrote:
> >
> > On Thu, 11 Oct 2018 11:38:10 -0500
> > Matt Weber <matthew.weber@rockwellcollins.com> wrote:
> >  
> > > From: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>
> > >
> > > This patch added device tree binding info for MAX31856 driver.
> > >
> > > Signed-off-by: Paresh Chaudhary <paresh.chaudhary@rockwellcollins.com>
> > > Signed-off-by: Matt Weber <matthew.weber@rockwellcollins.com>  
> > Device tree bindings should be cc'd to the devicetree list and maintainers.
> >
> > Thanks,
> >
> > Jonathan
> >  
> > > ---
> > > Changes v1 -> v2
> > > [Matt
> > >  - Removed comment block and added possibilities of
> > >    thermocouple type in device tree binding doc.
> > >
> > > ---
> > >  .../bindings/iio/temperature/max31856.txt          | 32 ++++++++++++++++++++++
> > >  MAINTAINERS                                        |  1 +
> > >  2 files changed, 33 insertions(+)
> > >  create mode 100644 Documentation/devicetree/bindings/iio/temperature/max31856.txt
> > >
> > > diff --git a/Documentation/devicetree/bindings/iio/temperature/max31856.txt b/Documentation/devicetree/bindings/iio/temperature/max31856.txt
> > > new file mode 100644
> > > index 0000000..e1def9f
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/iio/temperature/max31856.txt
> > > @@ -0,0 +1,32 @@
> > > +Maxim MAX31856 thermocouple support
> > > +
> > > +https://datasheets.maximintegrated.com/en/ds/MAX31856.pdf
> > > +
> > > +Required properties:
> > > +     - compatible: must be "max31856"
> > > +     - reg: SPI chip select number for the device
> > > +     - spi-max-frequency: As per datasheet max. supported freq is 5000000
> > > +     - spi-cpha: must be defined for max31856 to enable SPI mode 1
> > > +     - type: Type of thermocouple (By default is K-Type)
> > > +             0x00 : TYPE_B
> > > +             0x01 : TYPE_E
> > > +             0x02 : TYPE_J
> > > +             0x03 : TYPE_K (default)
> > > +             0x04 : TYPE_N
> > > +             0x05 : TYPE_R
> > > +             0x06 : TYPE_S
> > > +             0x07 : TYPE_T
> > > +
> > > +     Refer to spi/spi-bus.txt for generic SPI slave bindings.
> > > +
> > > +Optional properties:
> > > +     - one-shot: Enable one-shot Conversion mode (By default mode is auto)  
> >
> > Why is this something that should be in devicetree rather than controlled
> > in the driver in response to some userspace interaction?
> >
> >  
> There is no specific reason. This is just providing info to the driver
> so the driver can configure chip while probe for specified mode.
> I understand your concern but as of now, the driver does not have
> support to decide mode based on userspace interaction. We will work on
> that when we reopen for enhancement (e.g threshold for temp. range)

Hmm. The problem is that this should not be a devicetree decision and
if we allow it to be so, then we end up stuck with having to support
the interface here going forward. It also sets a precedence that
will get picked up by other drivers.

So, sorry but I really don't think this is a good idea.  For now you
may just have pick a default and go with it until you have the time
to add some automated switching between them at some later date.


Jonathan
> > > +
> > > + Example:
> > > +     max31856@0 {
> > > +             compatible = "max31856";
> > > +             reg = <0>;
> > > +             spi-max-frequency = <5000000>;
> > > +             spi-cpha;
> > > +             type = <0x03>;
> > > +     };
> > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > index dd9a83d..6482ae8 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -7161,6 +7161,7 @@ MAX31856 IIO DRIVER
> > >  M:   Matthew Weber <matthew.weber@rockwellcollins.com>
> > >  S:   Maintained
> > >  F:   drivers/iio/temperature/max31856.c
> > > +F:   Documentation/devicetree/bindings/iio/temperature/max31856.txt
> > >
> > >  IIO UNIT CONVERTER
> > >  M:   Peter Rosin <peda@axentia.se>  
> >
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/iio/temperature/max31856.txt b/Documentation/devicetree/bindings/iio/temperature/max31856.txt
new file mode 100644
index 0000000..e1def9f
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/temperature/max31856.txt
@@ -0,0 +1,32 @@ 
+Maxim MAX31856 thermocouple support
+
+https://datasheets.maximintegrated.com/en/ds/MAX31856.pdf
+
+Required properties:
+	- compatible: must be "max31856"
+	- reg: SPI chip select number for the device
+	- spi-max-frequency: As per datasheet max. supported freq is 5000000
+	- spi-cpha: must be defined for max31856 to enable SPI mode 1
+	- type: Type of thermocouple (By default is K-Type)
+		0x00 : TYPE_B
+		0x01 : TYPE_E
+		0x02 : TYPE_J
+		0x03 : TYPE_K (default)
+		0x04 : TYPE_N
+		0x05 : TYPE_R
+		0x06 : TYPE_S
+		0x07 : TYPE_T
+
+	Refer to spi/spi-bus.txt for generic SPI slave bindings.
+
+Optional properties:
+	- one-shot: Enable one-shot Conversion mode (By default mode is auto)
+
+ Example:
+	max31856@0 {
+		compatible = "max31856";
+		reg = <0>;
+		spi-max-frequency = <5000000>;
+		spi-cpha;
+		type = <0x03>;
+	};
diff --git a/MAINTAINERS b/MAINTAINERS
index dd9a83d..6482ae8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7161,6 +7161,7 @@  MAX31856 IIO DRIVER
 M:	Matthew Weber <matthew.weber@rockwellcollins.com>
 S:	Maintained
 F:	drivers/iio/temperature/max31856.c
+F:	Documentation/devicetree/bindings/iio/temperature/max31856.txt
 
 IIO UNIT CONVERTER
 M:	Peter Rosin <peda@axentia.se>