diff mbox series

[v3,02/10] dt-bindings: iio: adc: ad7606: Remove spi-cpha from required

Message ID 20241004-ad7606_add_iio_backend_support-v3-2-38757012ce82@baylibre.com (mailing list archive)
State Not Applicable
Headers show
Series Add iio backend compatibility for ad7606 | expand

Commit Message

Guillaume Stols Oct. 4, 2024, 9:48 p.m. UTC
The documentation is erroneously stating that spi-cpha is required, and
the example is erroneously setting both spi-cpol and spi-cpha. According
to the datasheet, only cpol should be set.

On zedboard for instance, setting the devicetree as in the example will
simply not work.

Fixes: 416f882c3b40 ("dt-bindings: iio: adc: Migrate AD7606 documentation to yaml")
Fixes: 6e33a125df66 ("dt-bindings: iio: adc: Add docs for AD7606 ADC")
Signed-off-by: Guillaume Stols <gstols@baylibre.com>
---
 Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

Comments

Rob Herring Oct. 5, 2024, 6:47 p.m. UTC | #1
On Fri, 04 Oct 2024 21:48:36 +0000, Guillaume Stols wrote:
> The documentation is erroneously stating that spi-cpha is required, and
> the example is erroneously setting both spi-cpol and spi-cpha. According
> to the datasheet, only cpol should be set.
> 
> On zedboard for instance, setting the devicetree as in the example will
> simply not work.
> 
> Fixes: 416f882c3b40 ("dt-bindings: iio: adc: Migrate AD7606 documentation to yaml")
> Fixes: 6e33a125df66 ("dt-bindings: iio: adc: Add docs for AD7606 ADC")
> Signed-off-by: Guillaume Stols <gstols@baylibre.com>
> ---
>  Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml
index bec7cfba52a7..47081c79a1cf 100644
--- a/Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml
@@ -39,6 +39,11 @@  properties:
   "#size-cells":
     const: 0
 
+  # According to the datasheet, "Data is clocked in from SDI on the falling
+  # edge of SCLK, while data is clocked out on DOUTA on the rising edge of
+  # SCLK".  Also, even if not stated textually in the datasheet, it is made
+  # clear on the diagrams that sclk idles at high.  Subsequently, in case SPI
+  # interface is used, the correct way is to only set spi-cpol.
   spi-cpha: true
 
   spi-cpol: true
@@ -168,7 +173,6 @@  patternProperties:
 required:
   - compatible
   - reg
-  - spi-cpha
   - avcc-supply
   - vdrive-supply
   - interrupts
@@ -255,7 +259,6 @@  examples:
             reg = <0>;
             spi-max-frequency = <1000000>;
             spi-cpol;
-            spi-cpha;
 
             avcc-supply = <&adc_vref>;
             vdrive-supply = <&vdd_supply>;
@@ -288,7 +291,6 @@  examples:
 
             spi-max-frequency = <1000000>;
             spi-cpol;
-            spi-cpha;
 
             avcc-supply = <&adc_vref>;
             vdrive-supply = <&vdd_supply>;