diff mbox series

[3/3] doc: iio: pressure: ms5611: added max SPI frequency setting to the example

Message ID 20221019125254.952588-3-mitja@lxnav.com
State Superseded
Headers show
Series None | expand

Commit Message

Mitja Spes Oct. 19, 2022, 12:52 p.m. UTC 
Added max SPI frequency setting to the example. It is now honored by the
driver.

Signed-off-by: Mitja Spes <mitja@lxnav.com>
---
 Documentation/devicetree/bindings/iio/pressure/meas,ms5611.yaml | 1 +
 1 file changed, 1 insertion(+)

Comments

Andy Shevchenko Oct. 19, 2022, 1:23 p.m. UTC | #1 
On Wed, Oct 19, 2022 at 3:55 PM Mitja Spes <mitja@lxnav.com> wrote:
>
> Added max SPI frequency setting to the example. It is now honored by the
> driver.

Is it possible to add a constraint here? So the schema validator will
issue the warning / error if the speed is too high.
Mitja Spes Oct. 20, 2022, 5:31 a.m. UTC | #2 
On Wed, Oct 19, 2022 at 3:23 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Wed, Oct 19, 2022 at 3:55 PM Mitja Spes <mitja@lxnav.com> wrote:
> >
> > Added max SPI frequency setting to the example. It is now honored by the
> > driver.
>
> Is it possible to add a constraint here? So the schema validator will
> issue the warning / error if the speed is too high.

The constraint is already there:
https://github.com/torvalds/linux/blob/master/Documentation/devicetree/bindings/iio/pressure/meas%2Cms5611.yaml
```
spi-max-frequency:
    maximum: 20000000
```

But in any case the patch 2/3 limits the max frequency.

Kind regards,
Mitja Spes
Mitja Spes Oct. 20, 2022, 5:40 a.m. UTC | #3 
On Wed, Oct 19, 2022 at 5:49 PM Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote:

> Use subject prefixes matching the subsystem (git log --oneline -- ...).

Will do.

> Whether it is honored by driver it matters less. More important is how
> hardware can handle it. This should be included in the bindings/properties.

The hardware handles frequencies up to 20MHz. That constraint is already
written in meas,ms5611.yaml.
What my patch 2 does is allow the user to set a lower frequency and the patch
3 just emphasises that in the example.

Kind regards,
Mitja
Krzysztof Kozlowski Oct. 20, 2022, noon UTC | #4 
On 20/10/2022 01:40, Mitja Špes wrote:
> On Wed, Oct 19, 2022 at 5:49 PM Krzysztof Kozlowski
> <krzysztof.kozlowski@linaro.org> wrote:
> 
>> Use subject prefixes matching the subsystem (git log --oneline -- ...).
> 
> Will do.
> 
>> Whether it is honored by driver it matters less. More important is how
>> hardware can handle it. This should be included in the bindings/properties.
> 
> The hardware handles frequencies up to 20MHz. That constraint is already
> written in meas,ms5611.yaml.
> What my patch 2 does is allow the user to set a lower frequency and the patch
> 3 just emphasises that in the example.

Then I am not sure whether it is worth changing. This is just an
example. Old value is correct.

Best regards,
Krzysztof
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/iio/pressure/meas,ms5611.yaml b/Documentation/devicetree/bindings/iio/pressure/meas,ms5611.yaml
index 4f06707450bf..08bd06e6dabe 100644
--- a/Documentation/devicetree/bindings/iio/pressure/meas,ms5611.yaml
+++ b/Documentation/devicetree/bindings/iio/pressure/meas,ms5611.yaml
@@ -52,6 +52,7 @@  examples:
             compatible = "meas,ms5611";
             reg = <0>;
             vdd-supply = <&ldo_3v3_gnss>;
+            spi-max-frequency = <20000000>;
         };
     };
 ...