[PATCH net-next 0/2] net: pse-pd: Plain I2C transport for Realtek Gen1

[PATCH net-next 0/2] net: pse-pd: Plain I2C transport for Realtek Gen1

[Sander Vanheule]

While for the Gen2 protocol both a plain I2C transport and an SMBus
transport were provided, Gen1 only got SMBus. The Unifi Switch Lite 16
PoE uses the Gen1 protocol to manage a single BCM59121, but does to
using plain I2C.

These patches simply add a new compatible for the plain I2C transport
and the associated match data. This is sufficient to let the existing
code talk to the management MCU.

Sander Vanheule (2):
  dt-bindings: net: pse-pd: realtek,pse: add gen1 I2C transport
  net: pse-pd: realtek-pse-mcu: add gen1 I2C transport

 .../bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml         | 7 +++++++
 drivers/net/pse-pd/realtek-pse-mcu-core.c                 | 8 +++++++-
 drivers/net/pse-pd/realtek-pse-mcu-i2c.c                  | 1 +
 drivers/net/pse-pd/realtek-pse-mcu.h                      | 1 +
 4 files changed, 16 insertions(+), 1 deletion(-)

-- 
2.56.0

[PATCH net-next 1/2] dt-bindings: net: pse-pd: realtek,pse: add gen1 I2C transport

[Sander Vanheule]

Like the gen2 protocol, the gen1 protocol can also be used over both a
raw I2C transport and an SMBUs transport. Add a compatible for the
former and the compatible for the Ubiquiti Unifi Switch Lite 16 PoE
device that uses it.

Signed-off-by: Sander Vanheule <sander@svanheule.net>
---
 .../bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml          | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml b/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml
index 3bb32349c28c..526f8525bb4d 100644
--- a/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml
+++ b/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml
@@ -54,6 +54,12 @@ properties:
               - zyxel,gs1920-24hp-v2-pse
           - const: realtek,pse-mcu-gen1-smbus
 
+      # I2C, raw framing
+      - items:
+          - enum:
+              - ubnt,usw-lite-16-poe-pse
+          - const: realtek,pse-mcu-gen1-i2c
+
       # UART
       - items:
           - enum:
@@ -100,6 +106,7 @@ allOf:
           contains:
             enum:
               - realtek,pse-mcu-gen1-smbus
+              - realtek,pse-mcu-gen1-i2c
               - realtek,pse-mcu-gen2-smbus
               - realtek,pse-mcu-gen2-i2c
     then:
-- 
2.56.0

Re: [PATCH net-next 1/2] dt-bindings: net: pse-pd: realtek,pse: add gen1 I2C transport

[Krzysztof Kozlowski]

On Sun, Oct 18, 2026 at 06:12:47PM +0200, Sander Vanheule wrote:
> Like the gen2 protocol, the gen1 protocol can also be used over both a
> raw I2C transport and an SMBUs transport. Add a compatible for the
> former and the compatible for the Ubiquiti Unifi Switch Lite 16 PoE
> device that uses it.
> 
> Signed-off-by: Sander Vanheule <sander@svanheule.net>
> ---
>  .../bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml          | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml b/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml
> index 3bb32349c28c..526f8525bb4d 100644
> --- a/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml
> +++ b/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml
> @@ -54,6 +54,12 @@ properties:
>                - zyxel,gs1920-24hp-v2-pse
>            - const: realtek,pse-mcu-gen1-smbus
>  
> +      # I2C, raw framing
> +      - items:
> +          - enum:
> +              - ubnt,usw-lite-16-poe-pse
> +          - const: realtek,pse-mcu-gen1-i2c
> +
>        # UART
>        - items:
>            - enum:
> @@ -100,6 +106,7 @@ allOf:
>            contains:
>              enum:
>                - realtek,pse-mcu-gen1-smbus
> +              - realtek,pse-mcu-gen1-i2c

That's the same device as smbus, no? Same device, same compatible.

You can have property deciding about protocol, if this cannot be deduced
from the clients.

Best regards,
Krzysztof

Re: [PATCH net-next 1/2] dt-bindings: net: pse-pd: realtek,pse: add gen1 I2C transport

[Jonas Jelonek]

Hi,

On 20.10.26 09:27, Krzysztof Kozlowski wrote:
> On Sun, Oct 18, 2026 at 06:12:47PM +0200, Sander Vanheule wrote:
>> Like the gen2 protocol, the gen1 protocol can also be used over both a
>> raw I2C transport and an SMBUs transport. Add a compatible for the
>> former and the compatible for the Ubiquiti Unifi Switch Lite 16 PoE
>> device that uses it.
>>
>> Signed-off-by: Sander Vanheule <sander@svanheule.net>
>> ---
>>  .../bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml          | 7 +++++++
>>  1 file changed, 7 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml b/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml
>> index 3bb32349c28c..526f8525bb4d 100644
>> --- a/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml
>> +++ b/Documentation/devicetree/bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml
>> @@ -54,6 +54,12 @@ properties:
>>                - zyxel,gs1920-24hp-v2-pse
>>            - const: realtek,pse-mcu-gen1-smbus
>>  
>> +      # I2C, raw framing
>> +      - items:
>> +          - enum:
>> +              - ubnt,usw-lite-16-poe-pse
>> +          - const: realtek,pse-mcu-gen1-i2c
>> +
>>        # UART
>>        - items:
>>            - enum:
>> @@ -100,6 +106,7 @@ allOf:
>>            contains:
>>              enum:
>>                - realtek,pse-mcu-gen1-smbus
>> +              - realtek,pse-mcu-gen1-i2c
> That's the same device as smbus, no? Same device, same compatible.

Physically it's the same device/MCU but the baked-in firmware and configuration
differs. Same for the UART vs. SMBus.

> You can have property deciding about protocol, if this cannot be deduced
> from the clients.

This was the approach in the early versions of the driver when I sent it
to the list. Rob favored the current way [1] and I think Conor was ok
with it later on.

[1] https://lore.kernel.org/netdev/20260615212959.GA1679454-robh@kernel.org/

> Best regards,
> Krzysztof

Best,
Jonas

Re: [PATCH net-next 1/2] dt-bindings: net: pse-pd: realtek,pse: add gen1 I2C transport

[Krzysztof Kozlowski]

On 18/10/2026 18:12, Sander Vanheule wrote:
> Like the gen2 protocol, the gen1 protocol can also be used over both a
> raw I2C transport and an SMBUs transport. Add a compatible for the
> former and the compatible for the Ubiquiti Unifi Switch Lite 16 PoE
> device that uses it.
> 
> Signed-off-by: Sander Vanheule <sander@svanheule.net>


Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Best regards,
Krzysztof

Re: [PATCH net-next 1/2] dt-bindings: net: pse-pd: realtek,pse: add gen1 I2C transport

[Rob Herring (Arm)]

On Sun, 18 Oct 2026 18:12:47 +0200, Sander Vanheule wrote:
> Like the gen2 protocol, the gen1 protocol can also be used over both a
> raw I2C transport and an SMBUs transport. Add a compatible for the
> former and the compatible for the Ubiquiti Unifi Switch Lite 16 PoE
> device that uses it.
> 
> Signed-off-by: Sander Vanheule <sander@svanheule.net>
> ---
>  .../bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml          | 7 +++++++
>  1 file changed, 7 insertions(+)
> 

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

[PATCH net-next 2/2] net: pse-pd: realtek-pse-mcu: add gen1 I2C transport

[Sander Vanheule]

Provide the required data for the gen1 raw I2C binding, which like for
gen2 is simply the gen1 protocol data with the native_i2c flag set.

Signed-off-by: Sander Vanheule <sander@svanheule.net>
---
 drivers/net/pse-pd/realtek-pse-mcu-core.c | 8 +++++++-
 drivers/net/pse-pd/realtek-pse-mcu-i2c.c  | 1 +
 drivers/net/pse-pd/realtek-pse-mcu.h      | 1 +
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/net/pse-pd/realtek-pse-mcu-core.c b/drivers/net/pse-pd/realtek-pse-mcu-core.c
index e64f13ea6e4e..c70b09ca2012 100644
--- a/drivers/net/pse-pd/realtek-pse-mcu-core.c
+++ b/drivers/net/pse-pd/realtek-pse-mcu-core.c
@@ -986,7 +986,13 @@ const struct rtpse_mcu_match_data rtpse_mcu_gen2_data = {
 };
 EXPORT_SYMBOL_GPL(rtpse_mcu_gen2_data);
 
-/* Same dialect as gen2, but the MCU expects raw-I2C framing. */
+/* Same dialects as above, but the MCU expects raw-I2C framing. */
+const struct rtpse_mcu_match_data rtpse_mcu_gen1_i2c_data = {
+	.dialect = &rtpse_mcu_dialect_gen1,
+	.native_i2c = true,
+};
+EXPORT_SYMBOL_GPL(rtpse_mcu_gen1_i2c_data);
+
 const struct rtpse_mcu_match_data rtpse_mcu_gen2_i2c_data = {
 	.dialect = &rtpse_mcu_dialect_gen2,
 	.native_i2c = true,
diff --git a/drivers/net/pse-pd/realtek-pse-mcu-i2c.c b/drivers/net/pse-pd/realtek-pse-mcu-i2c.c
index b6769ac1d470..bbded772eddf 100644
--- a/drivers/net/pse-pd/realtek-pse-mcu-i2c.c
+++ b/drivers/net/pse-pd/realtek-pse-mcu-i2c.c
@@ -128,6 +128,7 @@ static int rtpse_mcu_i2c_probe(struct i2c_client *client)
 
 static const struct of_device_id rtpse_mcu_i2c_of_match[] = {
 	{ .compatible = "realtek,pse-mcu-gen1-smbus", .data = &rtpse_mcu_gen1_data },
+	{ .compatible = "realtek,pse-mcu-gen1-i2c", .data = &rtpse_mcu_gen1_i2c_data },
 	{ .compatible = "realtek,pse-mcu-gen2-smbus", .data = &rtpse_mcu_gen2_data },
 	{ .compatible = "realtek,pse-mcu-gen2-i2c", .data = &rtpse_mcu_gen2_i2c_data },
 	{ /* sentinel */ }
diff --git a/drivers/net/pse-pd/realtek-pse-mcu.h b/drivers/net/pse-pd/realtek-pse-mcu.h
index d75e91669b8f..5e31dd0993dd 100644
--- a/drivers/net/pse-pd/realtek-pse-mcu.h
+++ b/drivers/net/pse-pd/realtek-pse-mcu.h
@@ -88,6 +88,7 @@ struct rtpse_mcu_ctrl {
 int rtpse_mcu_register(struct rtpse_mcu_ctrl *pse);
 
 extern const struct rtpse_mcu_match_data rtpse_mcu_gen1_data;
+extern const struct rtpse_mcu_match_data rtpse_mcu_gen1_i2c_data;
 extern const struct rtpse_mcu_match_data rtpse_mcu_gen2_data;
 extern const struct rtpse_mcu_match_data rtpse_mcu_gen2_i2c_data;
 
-- 
2.56.0

Re: [PATCH net-next 2/2] net: pse-pd: realtek-pse-mcu: add gen1 I2C transport

[Oleksij Rempel]

On Sun, Oct 18, 2026 at 06:12:48PM +0200, Sander Vanheule wrote:
> Provide the required data for the gen1 raw I2C binding, which like for
> gen2 is simply the gen1 protocol data with the native_i2c flag set.
> 
> Signed-off-by: Sander Vanheule <sander@svanheule.net>

Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>

Thank you!
-- 
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Re: [PATCH net-next 2/2] net: pse-pd: realtek-pse-mcu: add gen1 I2C transport

[Jonas Jelonek]

On 18.10.26 18:12, Sander Vanheule wrote:
> Provide the required data for the gen1 raw I2C binding, which like for
> gen2 is simply the gen1 protocol data with the native_i2c flag set.
>
> Signed-off-by: Sander Vanheule <sander@svanheule.net>
>

Acked-by: Jonas Jelonek <jonas@jonasjelonek.de>

Best,
Jonas

Re: [PATCH net-next 0/2] net: pse-pd: Plain I2C transport for Realtek Gen1

[Kory Maincent]

On 10/18/26 18:12, Sander Vanheule wrote:
> While for the Gen2 protocol both a plain I2C transport and an SMBus
> transport were provided, Gen1 only got SMBus. The Unifi Switch Lite 16
> PoE uses the Gen1 protocol to manage a single BCM59121, but does to
> using plain I2C.
> 
> These patches simply add a new compatible for the plain I2C transport
> and the associated match data. This is sufficient to let the existing
> code talk to the management MCU.

Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>

Thank you!

> Sander Vanheule (2):
>    dt-bindings: net: pse-pd: realtek,pse: add gen1 I2C transport
>    net: pse-pd: realtek-pse-mcu: add gen1 I2C transport
> 
>   .../bindings/net/pse-pd/realtek,pse-mcu-gen1.yaml         | 7 +++++++
>   drivers/net/pse-pd/realtek-pse-mcu-core.c                 | 8 +++++++-
>   drivers/net/pse-pd/realtek-pse-mcu-i2c.c                  | 1 +
>   drivers/net/pse-pd/realtek-pse-mcu.h                      | 1 +
>   4 files changed, 16 insertions(+), 1 deletion(-)
> 

-- 
Köry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com