diff mbox series

[v2,2/8] dt-bindings: iio: adc: Binding ast2600 adc.

Message ID 20210723081621.29477-3-billy_tsai@aspeedtech.com (mailing list archive)
State New, archived
Headers show
Series Add support for ast2600 ADC | expand

Commit Message

Billy Tsai July 23, 2021, 8:16 a.m. UTC
This patch add more description about aspeed adc and add two property
for ast2600:
- vref: used to configure reference voltage.
- battery-sensing: used to enable battery sensing mode for last channel.

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
---
 .../bindings/iio/adc/aspeed,adc.yaml          | 28 +++++++++++++++++--
 1 file changed, 26 insertions(+), 2 deletions(-)

Comments

Jonathan Cameron July 23, 2021, 2:51 p.m. UTC | #1
On Fri, 23 Jul 2021 16:16:15 +0800
Billy Tsai <billy_tsai@aspeedtech.com> wrote:

> This patch add more description about aspeed adc and add two property
> for ast2600:
> - vref: used to configure reference voltage.
> - battery-sensing: used to enable battery sensing mode for last channel.
> 
> Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>

Hi Billy,

A few comments inline.

Thanks,

Jonathan

> ---
>  .../bindings/iio/adc/aspeed,adc.yaml          | 28 +++++++++++++++++--
>  1 file changed, 26 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/iio/adc/aspeed,adc.yaml b/Documentation/devicetree/bindings/iio/adc/aspeed,adc.yaml
> index 23f3da1ffca3..a562a7fbc30c 100644
> --- a/Documentation/devicetree/bindings/iio/adc/aspeed,adc.yaml
> +++ b/Documentation/devicetree/bindings/iio/adc/aspeed,adc.yaml
> @@ -10,14 +10,26 @@ maintainers:
>    - Joel Stanley <joel@jms.id.au>
>  
>  description:

I think you need a | after description if you want the formatting to be
maintained (otherwise it will undo the line breaks).

> -  This device is a 10-bit converter for 16 voltage channels.  All inputs are
> -  single ended.
> +  • 10-bits resolution for 16 voltage channels.
> +  At ast2400/ast2500 the device has only one engine with 16 voltage channels.
> +  At ast2600 the device split into two individual engine and each contains 8 voltage channels.

Please wrap lines at 80 chars unless it badly hurts readability.
engines

> +  • Channel scanning can be non-continuous.
> +  • Programmable ADC clock frequency.
> +  • Programmable upper and lower bound for each channels.

I would use threshold rather than bound.   A bound restricts the
value, and I think this is measuring it?

> +  • Interrupt when larger or less than bounds for each channels.
> +  • Support hysteresis for each channels.
> +  • Buildin a compensating method.

Built-in 

> +  Additional feature at ast2600

of ast2600

> +  • Internal or External reference voltage.
> +  • Support 2 Internal reference voltage 1.2v or 2.5v.
> +  • Integrate dividing circuit for battery sensing.
>  
>  properties:
>    compatible:
>      enum:
>        - aspeed,ast2400-adc
>        - aspeed,ast2500-adc
> +      - aspeed,ast2600-adc
>  
>    reg:
>      maxItems: 1
> @@ -33,6 +45,18 @@ properties:
>    "#io-channel-cells":
>      const: 1
>  
> +  vref:
> +    minItems: 900
> +    maxItems: 2700
> +    default: 2500
> +    description:
> +      ADC Reference voltage in millivolts.

I'm not clear from this description.  Is this describing an externally
connected voltage reference?  If so it needs to be done as a regulator.
If it's a classic high precision reference, the dts can just use
a fixed regulator.

> +
> +  battery-sensing:
> +    type: boolean
> +    description:
> +      Inform the driver that last channel will be used to sensor battery.

This isn't (I think?) a standard dt binding, so it needs a manufacturer
prefix.

aspeed,battery-sensing

> +
>  required:
>    - compatible
>    - reg
Billy Tsai July 26, 2021, 7:21 a.m. UTC | #2
Hi Jonathan,

Thanks for your review. I will fix them.
About the vref I reply inline.

On 2021/7/23, 10:52 PM, "Jonathan Cameron" <Jonathan.Cameron@Huawei.com> wrote:

    On Fri, 23 Jul 2021 16:16:15 +0800
    Billy Tsai <billy_tsai@aspeedtech.com> wrote:

    >   > +  • Internal or External reference voltage.
    >   > +  • Support 2 Internal reference voltage 1.2v or 2.5v.
    >   > +  • Integrate dividing circuit for battery sensing.
    >   >  
    >   >  properties:
    >   >    compatible:
    >   >      enum:
    >   >        - aspeed,ast2400-adc
    >   >        - aspeed,ast2500-adc
    >   > +      - aspeed,ast2600-adc
    >   >  
    >   >    reg:
    >   >      maxItems: 1
    >   > @@ -33,6 +45,18 @@ properties:
    >   >    "#io-channel-cells":
    >   >      const: 1
    >   >  
    >   > +  vref:
    >   > +    minItems: 900
    >   > +    maxItems: 2700
    >   > +    default: 2500
    >   > +    description:
    >   > +      ADC Reference voltage in millivolts.

    >   I'm not clear from this description.  Is this describing an externally
    >   connected voltage reference?  If so it needs to be done as a regulator.
    >   If it's a classic high precision reference, the dts can just use
    >   a fixed regulator.

In the ast2600, the ADC supports two internal reference voltages of 1.2v or 2.5v,
as well as external voltages. When the user selects a voltage of 1.2v or 2.5v, my
driver will first select to use the internal voltage. 
As you mention at patch #4, you suggest to use two property to handle this feature.
vref: indicate the regulator handler. Like other dt-bindings used.
aspeed,int_vref_mv: indicate the chosen of 1.2v or 2.5v
and use "model_data->vref_fixed" to exclude ast2400 and ast2500
Is it right?

Thanks

    >   > +
    >   > +  battery-sensing:
    >   > +    type: boolean
    >   > +    description:
    >   > +      Inform the driver that last channel will be used to sensor battery.

    >   This isn't (I think?) a standard dt binding, so it needs a manufacturer
    >   prefix.

    >   aspeed,battery-sensing

Best Regards,
Billy Tsai
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/iio/adc/aspeed,adc.yaml b/Documentation/devicetree/bindings/iio/adc/aspeed,adc.yaml
index 23f3da1ffca3..a562a7fbc30c 100644
--- a/Documentation/devicetree/bindings/iio/adc/aspeed,adc.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/aspeed,adc.yaml
@@ -10,14 +10,26 @@  maintainers:
   - Joel Stanley <joel@jms.id.au>
 
 description:
-  This device is a 10-bit converter for 16 voltage channels.  All inputs are
-  single ended.
+  • 10-bits resolution for 16 voltage channels.
+  At ast2400/ast2500 the device has only one engine with 16 voltage channels.
+  At ast2600 the device split into two individual engine and each contains 8 voltage channels.
+  • Channel scanning can be non-continuous.
+  • Programmable ADC clock frequency.
+  • Programmable upper and lower bound for each channels.
+  • Interrupt when larger or less than bounds for each channels.
+  • Support hysteresis for each channels.
+  • Buildin a compensating method.
+  Additional feature at ast2600
+  • Internal or External reference voltage.
+  • Support 2 Internal reference voltage 1.2v or 2.5v.
+  • Integrate dividing circuit for battery sensing.
 
 properties:
   compatible:
     enum:
       - aspeed,ast2400-adc
       - aspeed,ast2500-adc
+      - aspeed,ast2600-adc
 
   reg:
     maxItems: 1
@@ -33,6 +45,18 @@  properties:
   "#io-channel-cells":
     const: 1
 
+  vref:
+    minItems: 900
+    maxItems: 2700
+    default: 2500
+    description:
+      ADC Reference voltage in millivolts.
+
+  battery-sensing:
+    type: boolean
+    description:
+      Inform the driver that last channel will be used to sensor battery.
+
 required:
   - compatible
   - reg