diff mbox series

[v5,04/15] dt-bindings: spi: dw: Add AMD Pensando Elba SoC SPI Controller bindings

Message ID 20220613195658.5607-5-brad@pensando.io (mailing list archive)
State New, archived
Headers show
Series Support AMD Pensando Elba SoC | expand

Commit Message

Brad Larson June 13, 2022, 7:56 p.m. UTC
From: Brad Larson <blarson@amd.com>

The AMD Pensando Elba SoC has integrated the DW APB SPI Controller

Signed-off-by: Brad Larson <blarson@amd.com>
---
 Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++
 1 file changed, 2 insertions(+)

Comments

Rob Herring (Arm) June 14, 2022, 9:23 p.m. UTC | #1
On Mon, 13 Jun 2022 12:56:47 -0700, Brad Larson wrote:
> From: Brad Larson <blarson@amd.com>
> 
> The AMD Pensando Elba SoC has integrated the DW APB SPI Controller
> 
> Signed-off-by: Brad Larson <blarson@amd.com>
> ---
>  Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++
>  1 file changed, 2 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>
Serge Semin June 20, 2022, 7:30 p.m. UTC | #2
On Mon, Jun 13, 2022 at 12:56:47PM -0700, Brad Larson wrote:
> From: Brad Larson <blarson@amd.com>
> 
> The AMD Pensando Elba SoC has integrated the DW APB SPI Controller
> 
> Signed-off-by: Brad Larson <blarson@amd.com>
> ---
>  Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> index e25d44c218f2..2a55b947cffc 100644
> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> @@ -73,6 +73,8 @@ properties:
>                - renesas,r9a06g032-spi # RZ/N1D
>                - renesas,r9a06g033-spi # RZ/N1S
>            - const: renesas,rzn1-spi   # RZ/N1

> +      - description: AMD Pensando Elba SoC SPI Controller
> +        const: amd,pensando-elba-spi

Not enough. The driver requires to have a phandle reference to the
Pensando System Controller. So the property like
"amd,pensando-elba-syscon" is also needed to be added to the DT schema
otherwise should the dt-schema tool correctly handle the
"unevaluatedProperties: false" setting (Rob says it isn't fully
supported at the moment), the dtbs_check procedure will fail on your
dts evaluation.

-Sergey

>  
>    reg:
>      minItems: 1
> -- 
> 2.17.1
>
Krzysztof Kozlowski June 20, 2022, 7:46 p.m. UTC | #3
On 20/06/2022 21:30, Serge Semin wrote:
> On Mon, Jun 13, 2022 at 12:56:47PM -0700, Brad Larson wrote:
>> From: Brad Larson <blarson@amd.com>
>>
>> The AMD Pensando Elba SoC has integrated the DW APB SPI Controller
>>
>> Signed-off-by: Brad Larson <blarson@amd.com>
>> ---
>>  Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
>> index e25d44c218f2..2a55b947cffc 100644
>> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
>> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
>> @@ -73,6 +73,8 @@ properties:
>>                - renesas,r9a06g032-spi # RZ/N1D
>>                - renesas,r9a06g033-spi # RZ/N1S
>>            - const: renesas,rzn1-spi   # RZ/N1
> 
>> +      - description: AMD Pensando Elba SoC SPI Controller
>> +        const: amd,pensando-elba-spi
> 
> Not enough. The driver requires to have a phandle reference to the
> Pensando System Controller. So the property like
> "amd,pensando-elba-syscon" is also needed to be added to the DT schema
> otherwise should the dt-schema tool correctly handle the
> "unevaluatedProperties: false" setting (Rob says it isn't fully
> supported at the moment), the dtbs_check procedure will fail on your
> dts evaluation.

The property was here before, now removed, so I assume it was also
removed from the driver and DTS. Isn't that the case?

Otherwise this is incomplete binding...

Best regards,
Krzysztof
Serge Semin June 20, 2022, 8:04 p.m. UTC | #4
On Mon, Jun 20, 2022 at 09:46:25PM +0200, Krzysztof Kozlowski wrote:
> On 20/06/2022 21:30, Serge Semin wrote:
> > On Mon, Jun 13, 2022 at 12:56:47PM -0700, Brad Larson wrote:
> >> From: Brad Larson <blarson@amd.com>
> >>
> >> The AMD Pensando Elba SoC has integrated the DW APB SPI Controller
> >>
> >> Signed-off-by: Brad Larson <blarson@amd.com>
> >> ---
> >>  Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++
> >>  1 file changed, 2 insertions(+)
> >>
> >> diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> >> index e25d44c218f2..2a55b947cffc 100644
> >> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> >> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> >> @@ -73,6 +73,8 @@ properties:
> >>                - renesas,r9a06g032-spi # RZ/N1D
> >>                - renesas,r9a06g033-spi # RZ/N1S
> >>            - const: renesas,rzn1-spi   # RZ/N1
> > 
> >> +      - description: AMD Pensando Elba SoC SPI Controller
> >> +        const: amd,pensando-elba-spi
> > 
> > Not enough. The driver requires to have a phandle reference to the
> > Pensando System Controller. So the property like
> > "amd,pensando-elba-syscon" is also needed to be added to the DT schema
> > otherwise should the dt-schema tool correctly handle the
> > "unevaluatedProperties: false" setting (Rob says it isn't fully
> > supported at the moment), the dtbs_check procedure will fail on your
> > dts evaluation.
> 

> The property was here before, now removed, so I assume it was also
> removed from the driver and DTS. Isn't that the case?

Ah, the property has been indeed removed. The driver now searches for
the system controller by the next compatible string:
"amd,pensando-elba-syscon" using the
syscon_regmap_lookup_by_compatible() method. My mistake. Sorry for the
noise.

* Though personally I'd prefer to have a property with the phandle
reference in order to signify the connection between the system controller
and the SPI-controller. Otherwise the implicit DT bindings like having
the "amd,pensando-elba-syscon"-compatible syscon gets to be
hidden behind the DT scene. But seeing we have already got the Microsemi
platform with such semantic, I can't insist on fixing this.

-Sergey

> 
> Otherwise this is incomplete binding...
> 
> Best regards,
> Krzysztof
Krzysztof Kozlowski June 21, 2022, 7 a.m. UTC | #5
On 20/06/2022 22:04, Serge Semin wrote:
> On Mon, Jun 20, 2022 at 09:46:25PM +0200, Krzysztof Kozlowski wrote:
>> On 20/06/2022 21:30, Serge Semin wrote:
>>> On Mon, Jun 13, 2022 at 12:56:47PM -0700, Brad Larson wrote:
>>>> From: Brad Larson <blarson@amd.com>
>>>>
>>>> The AMD Pensando Elba SoC has integrated the DW APB SPI Controller
>>>>
>>>> Signed-off-by: Brad Larson <blarson@amd.com>
>>>> ---
>>>>  Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++
>>>>  1 file changed, 2 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
>>>> index e25d44c218f2..2a55b947cffc 100644
>>>> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
>>>> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
>>>> @@ -73,6 +73,8 @@ properties:
>>>>                - renesas,r9a06g032-spi # RZ/N1D
>>>>                - renesas,r9a06g033-spi # RZ/N1S
>>>>            - const: renesas,rzn1-spi   # RZ/N1
>>>
>>>> +      - description: AMD Pensando Elba SoC SPI Controller
>>>> +        const: amd,pensando-elba-spi
>>>
>>> Not enough. The driver requires to have a phandle reference to the
>>> Pensando System Controller. So the property like
>>> "amd,pensando-elba-syscon" is also needed to be added to the DT schema
>>> otherwise should the dt-schema tool correctly handle the
>>> "unevaluatedProperties: false" setting (Rob says it isn't fully
>>> supported at the moment), the dtbs_check procedure will fail on your
>>> dts evaluation.
>>
> 
>> The property was here before, now removed, so I assume it was also
>> removed from the driver and DTS. Isn't that the case?
> 
> Ah, the property has been indeed removed. The driver now searches for
> the system controller by the next compatible string:
> "amd,pensando-elba-syscon" using the
> syscon_regmap_lookup_by_compatible() method. My mistake. Sorry for the
> noise.
> 
> * Though personally I'd prefer to have a property with the phandle
> reference in order to signify the connection between the system controller
> and the SPI-controller. Otherwise the implicit DT bindings like having
> the "amd,pensando-elba-syscon"-compatible syscon gets to be
> hidden behind the DT scene. But seeing we have already got the Microsemi
> platform with such semantic, I can't insist on fixing this.

I agree entirely, this should be explicit syscon-type property. Looking
up for compatibles:
 - creates hidden (not expressed via bindings) dependency between nodes,
 - is not portable and several people struggled with it later and needed
backward-compatible code (many examples, let's just give recent one: [1])


[1]
https://lore.kernel.org/all/20220619151225.209029-10-tmaimon77@gmail.com/


Best regards,
Krzysztof
Serge Semin June 21, 2022, 10:11 a.m. UTC | #6
On Tue, Jun 21, 2022 at 09:00:36AM +0200, Krzysztof Kozlowski wrote:
> On 20/06/2022 22:04, Serge Semin wrote:
> > On Mon, Jun 20, 2022 at 09:46:25PM +0200, Krzysztof Kozlowski wrote:
> >> On 20/06/2022 21:30, Serge Semin wrote:
> >>> On Mon, Jun 13, 2022 at 12:56:47PM -0700, Brad Larson wrote:
> >>>> From: Brad Larson <blarson@amd.com>
> >>>>
> >>>> The AMD Pensando Elba SoC has integrated the DW APB SPI Controller
> >>>>
> >>>> Signed-off-by: Brad Larson <blarson@amd.com>
> >>>> ---
> >>>>  Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++
> >>>>  1 file changed, 2 insertions(+)
> >>>>
> >>>> diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> >>>> index e25d44c218f2..2a55b947cffc 100644
> >>>> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> >>>> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> >>>> @@ -73,6 +73,8 @@ properties:
> >>>>                - renesas,r9a06g032-spi # RZ/N1D
> >>>>                - renesas,r9a06g033-spi # RZ/N1S
> >>>>            - const: renesas,rzn1-spi   # RZ/N1
> >>>
> >>>> +      - description: AMD Pensando Elba SoC SPI Controller
> >>>> +        const: amd,pensando-elba-spi
> >>>
> >>> Not enough. The driver requires to have a phandle reference to the
> >>> Pensando System Controller. So the property like
> >>> "amd,pensando-elba-syscon" is also needed to be added to the DT schema
> >>> otherwise should the dt-schema tool correctly handle the
> >>> "unevaluatedProperties: false" setting (Rob says it isn't fully
> >>> supported at the moment), the dtbs_check procedure will fail on your
> >>> dts evaluation.
> >>
> > 
> >> The property was here before, now removed, so I assume it was also
> >> removed from the driver and DTS. Isn't that the case?
> > 
> > Ah, the property has been indeed removed. The driver now searches for
> > the system controller by the next compatible string:
> > "amd,pensando-elba-syscon" using the
> > syscon_regmap_lookup_by_compatible() method. My mistake. Sorry for the
> > noise.
> > 

> > * Though personally I'd prefer to have a property with the phandle
> > reference in order to signify the connection between the system controller
> > and the SPI-controller. Otherwise the implicit DT bindings like having
> > the "amd,pensando-elba-syscon"-compatible syscon gets to be
> > hidden behind the DT scene. But seeing we have already got the Microsemi
> > platform with such semantic, I can't insist on fixing this.
> 
> I agree entirely, this should be explicit syscon-type property. Looking
> up for compatibles:
>  - creates hidden (not expressed via bindings) dependency between nodes,
>  - is not portable and several people struggled with it later and needed
> backward-compatible code (many examples, let's just give recent one: [1])
> 
> 
> [1]
> https://lore.kernel.org/all/20220619151225.209029-10-tmaimon77@gmail.com/

Seems even more reasonable now. Thanks for providing a bright example
justifying the property-based approach.

@Brad, could you get back the property with a phandle to the syscon
DT-node? (No need in adding the CS CSR address as the phandle argument,
just a phandle.)

-Sergey

> 
> 
> Best regards,
> Krzysztof
Brad Larson July 3, 2022, 11:58 p.m. UTC | #7
Hi Sergey,

On Tue, Jun 21, 2022 at 3:12 AM Serge Semin <fancer.lancer@gmail.com> wrote:
>
> On Tue, Jun 21, 2022 at 09:00:36AM +0200, Krzysztof Kozlowski wrote:
> > On 20/06/2022 22:04, Serge Semin wrote:
> > > On Mon, Jun 20, 2022 at 09:46:25PM +0200, Krzysztof Kozlowski wrote:
> > >> On 20/06/2022 21:30, Serge Semin wrote:
> > >>> On Mon, Jun 13, 2022 at 12:56:47PM -0700, Brad Larson wrote:
> > >>>> From: Brad Larson <blarson@amd.com>
> > >>>>
> > >>>> The AMD Pensando Elba SoC has integrated the DW APB SPI Controller
> > >>>>
> > >>>> Signed-off-by: Brad Larson <blarson@amd.com>
> > >>>> ---
> > >>>>  Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++
> > >>>>  1 file changed, 2 insertions(+)
> > >>>>
> > >>>> diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> > >>>> index e25d44c218f2..2a55b947cffc 100644
> > >>>> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> > >>>> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> > >>>> @@ -73,6 +73,8 @@ properties:
> > >>>>                - renesas,r9a06g032-spi # RZ/N1D
> > >>>>                - renesas,r9a06g033-spi # RZ/N1S
> > >>>>            - const: renesas,rzn1-spi   # RZ/N1
> > >>>
> > >>>> +      - description: AMD Pensando Elba SoC SPI Controller
> > >>>> +        const: amd,pensando-elba-spi
> > >>>
> > >>> Not enough. The driver requires to have a phandle reference to the
> > >>> Pensando System Controller. So the property like
> > >>> "amd,pensando-elba-syscon" is also needed to be added to the DT schema
> > >>> otherwise should the dt-schema tool correctly handle the
> > >>> "unevaluatedProperties: false" setting (Rob says it isn't fully
> > >>> supported at the moment), the dtbs_check procedure will fail on your
> > >>> dts evaluation.
> > >>
> > >
> > >> The property was here before, now removed, so I assume it was also
> > >> removed from the driver and DTS. Isn't that the case?
> > >
> > > Ah, the property has been indeed removed. The driver now searches for
> > > the system controller by the next compatible string:
> > > "amd,pensando-elba-syscon" using the
> > > syscon_regmap_lookup_by_compatible() method. My mistake. Sorry for the
> > > noise.
> > >
>
> > > * Though personally I'd prefer to have a property with the phandle
> > > reference in order to signify the connection between the system controller
> > > and the SPI-controller. Otherwise the implicit DT bindings like having
> > > the "amd,pensando-elba-syscon"-compatible syscon gets to be
> > > hidden behind the DT scene. But seeing we have already got the Microsemi
> > > platform with such semantic, I can't insist on fixing this.
> >
> > I agree entirely, this should be explicit syscon-type property. Looking
> > up for compatibles:
> >  - creates hidden (not expressed via bindings) dependency between nodes,
> >  - is not portable and several people struggled with it later and needed
> > backward-compatible code (many examples, let's just give recent one: [1])
> >
> >
> > [1]
> > https://lore.kernel.org/all/20220619151225.209029-10-tmaimon77@gmail.com/
>
> Seems even more reasonable now. Thanks for providing a bright example
> justifying the property-based approach.
>
> @Brad, could you get back the property with a phandle to the syscon
> DT-node? (No need in adding the CS CSR address as the phandle argument,
> just a phandle.)

Replying to the sequence of review inputs.  The below change to
version 5 brings back the phandle without the earlier argument that
complicated the binding (was the motivation for moving in this
direction in earlier version).  Passes dtbs_check.

--- a/drivers/spi/spi-dw-mmio.c
+++ b/drivers/spi/spi-dw-mmio.c
@@ -285,12 +285,17 @@ static void dw_spi_elba_set_cs(struct spi_device
*spi, bool enable)
 static int dw_spi_elba_init(struct platform_device *pdev,
                            struct dw_spi_mmio *dwsmmio)
 {
+       struct device_node *np = pdev->dev.of_node;
+       struct device_node *node;
        struct dw_spi_elba *dwselba;
        struct regmap *regmap;

-       regmap = syscon_regmap_lookup_by_compatible("amd,pensando-elba-syscon");
-       if (IS_ERR(regmap))
-               return PTR_ERR(regmap);
+       node = of_parse_phandle(np, "pensando,elba-syscon-spics", 0);
+       if (node) {
+               regmap = syscon_node_to_regmap(node);
+               if (IS_ERR(regmap))
+                       return PTR_ERR(regmap);
+       }

diff --git a/arch/arm64/boot/dts/amd/elba.dtsi
b/arch/arm64/boot/dts/amd/elba.dtsi
index 9739641261c3..ec48be4cfe48 100644
--- a/arch/arm64/boot/dts/amd/elba.dtsi
+++ b/arch/arm64/boot/dts/amd/elba.dtsi
@@ -98,6 +98,7 @@
                        reg = <0x0 0x2800 0x0 0x100>;
                        #address-cells = <1>;
                        #size-cells = <0>;
+                       pensando,elba-syscon-spics = <&syscon>;
                        clocks = <&ahb_clk>;
                        interrupts = <GIC_SPI 9 IRQ_TYPE_LEVEL_HIGH>;
                        num-cs = <2>;

--- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
+++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
@@ -37,6 +37,15 @@ allOf:
     else:
       required:
         - interrupts
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - amd,pensando-elba-spi
+    then:
+      required:
+        - pensando,elba-syscon-spics

 properties:
   compatible:

Regards,
Brad
Serge Semin July 4, 2022, 1:18 p.m. UTC | #8
On Sun, Jul 03, 2022 at 04:58:09PM -0700, Brad Larson wrote:
> Hi Sergey,
> 
> On Tue, Jun 21, 2022 at 3:12 AM Serge Semin <fancer.lancer@gmail.com> wrote:
> >
> > On Tue, Jun 21, 2022 at 09:00:36AM +0200, Krzysztof Kozlowski wrote:
> > > On 20/06/2022 22:04, Serge Semin wrote:
> > > > On Mon, Jun 20, 2022 at 09:46:25PM +0200, Krzysztof Kozlowski wrote:
> > > >> On 20/06/2022 21:30, Serge Semin wrote:
> > > >>> On Mon, Jun 13, 2022 at 12:56:47PM -0700, Brad Larson wrote:
> > > >>>> From: Brad Larson <blarson@amd.com>
> > > >>>>
> > > >>>> The AMD Pensando Elba SoC has integrated the DW APB SPI Controller
> > > >>>>
> > > >>>> Signed-off-by: Brad Larson <blarson@amd.com>
> > > >>>> ---
> > > >>>>  Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++
> > > >>>>  1 file changed, 2 insertions(+)
> > > >>>>
> > > >>>> diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> > > >>>> index e25d44c218f2..2a55b947cffc 100644
> > > >>>> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> > > >>>> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> > > >>>> @@ -73,6 +73,8 @@ properties:
> > > >>>>                - renesas,r9a06g032-spi # RZ/N1D
> > > >>>>                - renesas,r9a06g033-spi # RZ/N1S
> > > >>>>            - const: renesas,rzn1-spi   # RZ/N1
> > > >>>
> > > >>>> +      - description: AMD Pensando Elba SoC SPI Controller
> > > >>>> +        const: amd,pensando-elba-spi
> > > >>>
> > > >>> Not enough. The driver requires to have a phandle reference to the
> > > >>> Pensando System Controller. So the property like
> > > >>> "amd,pensando-elba-syscon" is also needed to be added to the DT schema
> > > >>> otherwise should the dt-schema tool correctly handle the
> > > >>> "unevaluatedProperties: false" setting (Rob says it isn't fully
> > > >>> supported at the moment), the dtbs_check procedure will fail on your
> > > >>> dts evaluation.
> > > >>
> > > >
> > > >> The property was here before, now removed, so I assume it was also
> > > >> removed from the driver and DTS. Isn't that the case?
> > > >
> > > > Ah, the property has been indeed removed. The driver now searches for
> > > > the system controller by the next compatible string:
> > > > "amd,pensando-elba-syscon" using the
> > > > syscon_regmap_lookup_by_compatible() method. My mistake. Sorry for the
> > > > noise.
> > > >
> >
> > > > * Though personally I'd prefer to have a property with the phandle
> > > > reference in order to signify the connection between the system controller
> > > > and the SPI-controller. Otherwise the implicit DT bindings like having
> > > > the "amd,pensando-elba-syscon"-compatible syscon gets to be
> > > > hidden behind the DT scene. But seeing we have already got the Microsemi
> > > > platform with such semantic, I can't insist on fixing this.
> > >
> > > I agree entirely, this should be explicit syscon-type property. Looking
> > > up for compatibles:
> > >  - creates hidden (not expressed via bindings) dependency between nodes,
> > >  - is not portable and several people struggled with it later and needed
> > > backward-compatible code (many examples, let's just give recent one: [1])
> > >
> > >
> > > [1]
> > > https://lore.kernel.org/all/20220619151225.209029-10-tmaimon77@gmail.com/
> >
> > Seems even more reasonable now. Thanks for providing a bright example
> > justifying the property-based approach.
> >
> > @Brad, could you get back the property with a phandle to the syscon
> > DT-node? (No need in adding the CS CSR address as the phandle argument,
> > just a phandle.)
> 
> Replying to the sequence of review inputs.  The below change to
> version 5 brings back the phandle without the earlier argument that
> complicated the binding (was the motivation for moving in this
> direction in earlier version).  Passes dtbs_check.
> 
> --- a/drivers/spi/spi-dw-mmio.c
> +++ b/drivers/spi/spi-dw-mmio.c
> @@ -285,12 +285,17 @@ static void dw_spi_elba_set_cs(struct spi_device
> *spi, bool enable)
>  static int dw_spi_elba_init(struct platform_device *pdev,
>                             struct dw_spi_mmio *dwsmmio)
>  {
> +       struct device_node *np = pdev->dev.of_node;
> +       struct device_node *node;
>         struct dw_spi_elba *dwselba;
>         struct regmap *regmap;
> 
> -       regmap = syscon_regmap_lookup_by_compatible("amd,pensando-elba-syscon");
> -       if (IS_ERR(regmap))
> -               return PTR_ERR(regmap);

> +       node = of_parse_phandle(np, "pensando,elba-syscon-spics", 0);

1. Property name must be structured with the permitted vendor-prefix. In
your case it's "amd," not "pensando,".
2. Having 'spics' in the property name doesn't make much sense since
the property is supposed to contain a phandle reference to the whole
syscon node.

So to speak the property with name like 'amd,pensando-elba-syscon'
seems more appropriate here.

> +       if (node) {
> +               regmap = syscon_node_to_regmap(node);
> +               if (IS_ERR(regmap))
> +                       return PTR_ERR(regmap);
> +       }
> 
> diff --git a/arch/arm64/boot/dts/amd/elba.dtsi
> b/arch/arm64/boot/dts/amd/elba.dtsi
> index 9739641261c3..ec48be4cfe48 100644
> --- a/arch/arm64/boot/dts/amd/elba.dtsi
> +++ b/arch/arm64/boot/dts/amd/elba.dtsi
> @@ -98,6 +98,7 @@
>                         reg = <0x0 0x2800 0x0 0x100>;
>                         #address-cells = <1>;
>                         #size-cells = <0>;

> +                       pensando,elba-syscon-spics = <&syscon>;
  +                       amd,pensando-elba-syscon = <&syscon>;

ditto

>                         clocks = <&ahb_clk>;
>                         interrupts = <GIC_SPI 9 IRQ_TYPE_LEVEL_HIGH>;
>                         num-cs = <2>;
> 
> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
> @@ -37,6 +37,15 @@ allOf:
>      else:
>        required:
>          - interrupts
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - amd,pensando-elba-spi
> +    then:
  +      properties:
  +        amd,pensando-elba-syscon
  +          $ref: /schemas/types.yaml#/definitions/phandle
  +          description: AMD Pensando Elba SoC system controller
> +      required:
> +        - amd,pensando-elba-syscon

Please make sure the DT-bindings check passes correctly.

-Sergey

> 
>  properties:
>    compatible:
> 
> Regards,
> Brad
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
index e25d44c218f2..2a55b947cffc 100644
--- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
+++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml
@@ -73,6 +73,8 @@  properties:
               - renesas,r9a06g032-spi # RZ/N1D
               - renesas,r9a06g033-spi # RZ/N1S
           - const: renesas,rzn1-spi   # RZ/N1
+      - description: AMD Pensando Elba SoC SPI Controller
+        const: amd,pensando-elba-spi
 
   reg:
     minItems: 1