diff mbox series

[v5,02/10] dt-bindings: aspeed-sgpio: Add ast2600 sgpio compatibles.

Message ID 20210608102547.4880-3-steven_lee@aspeedtech.com
State New
Headers show
Series ASPEED sgpio driver enhancement. | expand

Commit Message

Steven Lee June 8, 2021, 10:25 a.m. UTC
AST2600 SoC has 2 SGPIO master interfaces one with 128 pins another one
with 80 pins. Add ast2600-sgpiom0-80 and ast2600-sgpiom-128 compatibles
and update descriptions to introduce the max number of available gpio
pins that AST2600 supported.

Signed-off-by: Steven Lee <steven_lee@aspeedtech.com>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
---
 Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Comments

Rob Herring June 10, 2021, 4:23 p.m. UTC | #1
On Tue, Jun 08, 2021 at 06:25:37PM +0800, Steven Lee wrote:
> AST2600 SoC has 2 SGPIO master interfaces one with 128 pins another one
> with 80 pins. Add ast2600-sgpiom0-80 and ast2600-sgpiom-128 compatibles
> and update descriptions to introduce the max number of available gpio
> pins that AST2600 supported.
> 
> Signed-off-by: Steven Lee <steven_lee@aspeedtech.com>
> Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
> ---
>  Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml b/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
> index b2ae211411ff..0e42eded3c1e 100644
> --- a/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
> +++ b/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
> @@ -10,9 +10,10 @@ maintainers:
>    - Andrew Jeffery <andrew@aj.id.au>
>  
>  description:
> -  This SGPIO controller is for ASPEED AST2500 SoC, it supports up to 80 full
> -  featured Serial GPIOs. Each of the Serial GPIO pins can be programmed to
> -  support the following options
> +  This SGPIO controller is for ASPEED AST2400, AST2500 and AST2600 SoC,
> +  AST2600 have two sgpio master one with 128 pins another one with 80 pins,
> +  AST2500/AST2400 have one sgpio master with 80 pins. Each of the Serial
> +  GPIO pins can be programmed to support the following options
>    - Support interrupt option for each input port and various interrupt
>      sensitivity option (level-high, level-low, edge-high, edge-low)
>    - Support reset tolerance option for each output port
> @@ -25,6 +26,8 @@ properties:
>      enum:
>        - aspeed,ast2400-sgpio
>        - aspeed,ast2500-sgpio
> +      - aspeed,ast2600-sgpiom-80
> +      - aspeed,ast2600-sgpiom-128

If the number of GPIOs is the only difference, then I don't think you 
should get rid of ngpios. It's one thing if it varies from one SoC to 
the next, but if something is per instance we should have a property.

Rob
Andrew Jeffery June 10, 2021, 11:27 p.m. UTC | #2
On Fri, 11 Jun 2021, at 01:53, Rob Herring wrote:
> On Tue, Jun 08, 2021 at 06:25:37PM +0800, Steven Lee wrote:
> > AST2600 SoC has 2 SGPIO master interfaces one with 128 pins another one
> > with 80 pins. Add ast2600-sgpiom0-80 and ast2600-sgpiom-128 compatibles
> > and update descriptions to introduce the max number of available gpio
> > pins that AST2600 supported.
> > 
> > Signed-off-by: Steven Lee <steven_lee@aspeedtech.com>
> > Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
> > ---
> >  Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml | 9 ++++++---
> >  1 file changed, 6 insertions(+), 3 deletions(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml b/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
> > index b2ae211411ff..0e42eded3c1e 100644
> > --- a/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
> > +++ b/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
> > @@ -10,9 +10,10 @@ maintainers:
> >    - Andrew Jeffery <andrew@aj.id.au>
> >  
> >  description:
> > -  This SGPIO controller is for ASPEED AST2500 SoC, it supports up to 80 full
> > -  featured Serial GPIOs. Each of the Serial GPIO pins can be programmed to
> > -  support the following options
> > +  This SGPIO controller is for ASPEED AST2400, AST2500 and AST2600 SoC,
> > +  AST2600 have two sgpio master one with 128 pins another one with 80 pins,
> > +  AST2500/AST2400 have one sgpio master with 80 pins. Each of the Serial
> > +  GPIO pins can be programmed to support the following options
> >    - Support interrupt option for each input port and various interrupt
> >      sensitivity option (level-high, level-low, edge-high, edge-low)
> >    - Support reset tolerance option for each output port
> > @@ -25,6 +26,8 @@ properties:
> >      enum:
> >        - aspeed,ast2400-sgpio
> >        - aspeed,ast2500-sgpio
> > +      - aspeed,ast2600-sgpiom-80
> > +      - aspeed,ast2600-sgpiom-128
> 
> If the number of GPIOs is the only difference, then I don't think you 
> should get rid of ngpios. It's one thing if it varies from one SoC to 
> the next, but if something is per instance we should have a property.
> 

There are two issues:

1. The maximum number of GPIOs supported by the controller
2. The maximum number of GPIOs supported by the platform

These are different because of what the controller does - here's some previous discussion on the topic:

https://lore.kernel.org/linux-gpio/f2875111-9ba9-43b7-b2a4-d00c8725f5a0@www.fastmail.com/

We've used ngpios to describe 2; this decision was made prior to the 2600 design - the SGPIO controller for both the 2400 and 2500 supported a maximum of 80 GPIOs. With the 2600 we have to differentiate between the two SGPIO controllers because they support a different maximum number of GPIOs. The proposed approach of different compatibles keeps the behaviour of ngpios the same across all controller implementations.

Cheers,

Andrew
Rob Herring June 16, 2021, 3:20 p.m. UTC | #3
On Thu, Jun 10, 2021 at 5:27 PM Andrew Jeffery <andrew@aj.id.au> wrote:
>
>
>
> On Fri, 11 Jun 2021, at 01:53, Rob Herring wrote:
> > On Tue, Jun 08, 2021 at 06:25:37PM +0800, Steven Lee wrote:
> > > AST2600 SoC has 2 SGPIO master interfaces one with 128 pins another one
> > > with 80 pins. Add ast2600-sgpiom0-80 and ast2600-sgpiom-128 compatibles
> > > and update descriptions to introduce the max number of available gpio
> > > pins that AST2600 supported.
> > >
> > > Signed-off-by: Steven Lee <steven_lee@aspeedtech.com>
> > > Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
> > > ---
> > >  Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml | 9 ++++++---
> > >  1 file changed, 6 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml b/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
> > > index b2ae211411ff..0e42eded3c1e 100644
> > > --- a/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
> > > +++ b/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
> > > @@ -10,9 +10,10 @@ maintainers:
> > >    - Andrew Jeffery <andrew@aj.id.au>
> > >
> > >  description:
> > > -  This SGPIO controller is for ASPEED AST2500 SoC, it supports up to 80 full
> > > -  featured Serial GPIOs. Each of the Serial GPIO pins can be programmed to
> > > -  support the following options
> > > +  This SGPIO controller is for ASPEED AST2400, AST2500 and AST2600 SoC,
> > > +  AST2600 have two sgpio master one with 128 pins another one with 80 pins,
> > > +  AST2500/AST2400 have one sgpio master with 80 pins. Each of the Serial
> > > +  GPIO pins can be programmed to support the following options
> > >    - Support interrupt option for each input port and various interrupt
> > >      sensitivity option (level-high, level-low, edge-high, edge-low)
> > >    - Support reset tolerance option for each output port
> > > @@ -25,6 +26,8 @@ properties:
> > >      enum:
> > >        - aspeed,ast2400-sgpio
> > >        - aspeed,ast2500-sgpio
> > > +      - aspeed,ast2600-sgpiom-80
> > > +      - aspeed,ast2600-sgpiom-128
> >
> > If the number of GPIOs is the only difference, then I don't think you
> > should get rid of ngpios. It's one thing if it varies from one SoC to
> > the next, but if something is per instance we should have a property.
> >
>
> There are two issues:
>
> 1. The maximum number of GPIOs supported by the controller
> 2. The maximum number of GPIOs supported by the platform
>
> These are different because of what the controller does - here's some previous discussion on the topic:
>
> https://lore.kernel.org/linux-gpio/f2875111-9ba9-43b7-b2a4-d00c8725f5a0@www.fastmail.com/
>
> We've used ngpios to describe 2; this decision was made prior to the 2600 design - the SGPIO controller for both the 2400 and 2500 supported a maximum of 80 GPIOs. With the 2600 we have to differentiate between the two SGPIO controllers because they support a different maximum number of GPIOs. The proposed approach of different compatibles keeps the behaviour of ngpios the same across all controller implementations.

Okay, that makes sense.

Reviewed-by: Rob Herring <robh@kernel.org>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml b/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
index b2ae211411ff..0e42eded3c1e 100644
--- a/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
+++ b/Documentation/devicetree/bindings/gpio/aspeed,sgpio.yaml
@@ -10,9 +10,10 @@  maintainers:
   - Andrew Jeffery <andrew@aj.id.au>
 
 description:
-  This SGPIO controller is for ASPEED AST2500 SoC, it supports up to 80 full
-  featured Serial GPIOs. Each of the Serial GPIO pins can be programmed to
-  support the following options
+  This SGPIO controller is for ASPEED AST2400, AST2500 and AST2600 SoC,
+  AST2600 have two sgpio master one with 128 pins another one with 80 pins,
+  AST2500/AST2400 have one sgpio master with 80 pins. Each of the Serial
+  GPIO pins can be programmed to support the following options
   - Support interrupt option for each input port and various interrupt
     sensitivity option (level-high, level-low, edge-high, edge-low)
   - Support reset tolerance option for each output port
@@ -25,6 +26,8 @@  properties:
     enum:
       - aspeed,ast2400-sgpio
       - aspeed,ast2500-sgpio
+      - aspeed,ast2600-sgpiom-80
+      - aspeed,ast2600-sgpiom-128
 
   reg:
     maxItems: 1