diff mbox series

[net-next,v4,2/4] dt-bindings: net: Add Rx/Tx output configuration for 10base T1L

Message ID 20201117201555.26723-3-dmurphy@ti.com
State Changes Requested, archived
Headers show
Series DP83TD510 Single Pair 10Mbps Ethernet PHY | expand

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Commit Message

Dan Murphy Nov. 17, 2020, 8:15 p.m. UTC
Per the 802.3cg spec the 10base T1L can operate at 2 different
differential voltages 1v p2p and 2.4v p2p. The abiility of the PHY to
drive that output is dependent on the PHY's on board power supply.
This common feature is applicable to all 10base T1L PHYs so this binding
property belongs in a top level ethernet document.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
---
 Documentation/devicetree/bindings/net/ethernet-phy.yaml | 6 ++++++
 1 file changed, 6 insertions(+)

Comments

Andrew Lunn Nov. 17, 2020, 8:31 p.m. UTC | #1
On Tue, Nov 17, 2020 at 02:15:53PM -0600, Dan Murphy wrote:
> Per the 802.3cg spec the 10base T1L can operate at 2 different
> differential voltages 1v p2p and 2.4v p2p. The abiility of the PHY to

ability

> drive that output is dependent on the PHY's on board power supply.
> This common feature is applicable to all 10base T1L PHYs so this binding
> property belongs in a top level ethernet document.
> 
> Signed-off-by: Dan Murphy <dmurphy@ti.com>
> ---
>  Documentation/devicetree/bindings/net/ethernet-phy.yaml | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> index 6dd72faebd89..bda1ce51836b 100644
> --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> @@ -174,6 +174,12 @@ properties:
>        PHY's that have configurable TX internal delays. If this property is
>        present then the PHY applies the TX delay.
>  
> +  max-tx-rx-p2p-microvolt:
> +    description: |
> +      Configures the Tx/Rx p2p differential output voltage for 10base-T1L PHYs.

Does it configure, or does it limit? I _think_ this is a negotiation
parameter, so the PHY might decide to do 1100mV if the link peer is
near by even when max-tx-rx-p2p-microvolt has the higher value.

     Andrew
Dan Murphy Nov. 17, 2020, 8:36 p.m. UTC | #2
Andrew

On 11/17/20 2:31 PM, Andrew Lunn wrote:
> On Tue, Nov 17, 2020 at 02:15:53PM -0600, Dan Murphy wrote:
>> Per the 802.3cg spec the 10base T1L can operate at 2 different
>> differential voltages 1v p2p and 2.4v p2p. The abiility of the PHY to
> ability
Ack
>
>> drive that output is dependent on the PHY's on board power supply.
>> This common feature is applicable to all 10base T1L PHYs so this binding
>> property belongs in a top level ethernet document.
>>
>> Signed-off-by: Dan Murphy <dmurphy@ti.com>
>> ---
>>   Documentation/devicetree/bindings/net/ethernet-phy.yaml | 6 ++++++
>>   1 file changed, 6 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
>> index 6dd72faebd89..bda1ce51836b 100644
>> --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
>> +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
>> @@ -174,6 +174,12 @@ properties:
>>         PHY's that have configurable TX internal delays. If this property is
>>         present then the PHY applies the TX delay.
>>   
>> +  max-tx-rx-p2p-microvolt:
>> +    description: |
>> +      Configures the Tx/Rx p2p differential output voltage for 10base-T1L PHYs.
> Does it configure, or does it limit? I _think_ this is a negotiation
> parameter, so the PHY might decide to do 1100mV if the link peer is
> near by even when max-tx-rx-p2p-microvolt has the higher value.

For this device we can configure or force it to only work at 1.1v p2p 
otherwise 2.4 is the default.

But each LP's have to be configured for the same voltage. unless auto 
negotiation is on then it negotiates the voltage.

Dan

>
>       Andrew
Rob Herring (Arm) Dec. 1, 2020, 12:02 a.m. UTC | #3
On Tue, Nov 17, 2020 at 02:15:53PM -0600, Dan Murphy wrote:
> Per the 802.3cg spec the 10base T1L can operate at 2 different
> differential voltages 1v p2p and 2.4v p2p. The abiility of the PHY to

1.1V?

> drive that output is dependent on the PHY's on board power supply.
> This common feature is applicable to all 10base T1L PHYs so this binding
> property belongs in a top level ethernet document.
> 
> Signed-off-by: Dan Murphy <dmurphy@ti.com>
> ---
>  Documentation/devicetree/bindings/net/ethernet-phy.yaml | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> index 6dd72faebd89..bda1ce51836b 100644
> --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> @@ -174,6 +174,12 @@ properties:
>        PHY's that have configurable TX internal delays. If this property is
>        present then the PHY applies the TX delay.
>  
> +  max-tx-rx-p2p-microvolt:
> +    description: |

Don't need '|' if no formatting.

> +      Configures the Tx/Rx p2p differential output voltage for 10base-T1L PHYs.
> +    enum: [ 1100, 2400 ]
> +    default: 2400

Aren't you off by 1000?

> +
>  required:
>    - reg
>  
> -- 
> 2.29.2
>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
index 6dd72faebd89..bda1ce51836b 100644
--- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
+++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
@@ -174,6 +174,12 @@  properties:
       PHY's that have configurable TX internal delays. If this property is
       present then the PHY applies the TX delay.
 
+  max-tx-rx-p2p-microvolt:
+    description: |
+      Configures the Tx/Rx p2p differential output voltage for 10base-T1L PHYs.
+    enum: [ 1100, 2400 ]
+    default: 2400
+
 required:
   - reg