2021-06-08 10:29:10

by Steven Lee

[permalink] [raw]
Subject: [PATCH v5 02/10] dt-bindings: aspeed-sgpio: Add ast2600 sgpio compatibles.

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 <[email protected]>
Reviewed-by: Andrew Jeffery <[email protected]>
---
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 <[email protected]>

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
--
2.17.1


2021-06-10 16:24:53

by Rob Herring

[permalink] [raw]
Subject: Re: [PATCH v5 02/10] dt-bindings: aspeed-sgpio: Add ast2600 sgpio compatibles.

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 <[email protected]>
> Reviewed-by: Andrew Jeffery <[email protected]>
> ---
> 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 <[email protected]>
>
> 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

2021-06-10 23:31:09

by Andrew Jeffery

[permalink] [raw]
Subject: Re: [PATCH v5 02/10] dt-bindings: aspeed-sgpio: Add ast2600 sgpio compatibles.



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 <[email protected]>
> > Reviewed-by: Andrew Jeffery <[email protected]>
> > ---
> > 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 <[email protected]>
> >
> > 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/[email protected]/

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

2021-06-16 19:23:36

by Rob Herring

[permalink] [raw]
Subject: Re: [PATCH v5 02/10] dt-bindings: aspeed-sgpio: Add ast2600 sgpio compatibles.

On Thu, Jun 10, 2021 at 5:27 PM Andrew Jeffery <[email protected]> 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 <[email protected]>
> > > Reviewed-by: Andrew Jeffery <[email protected]>
> > > ---
> > > 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 <[email protected]>
> > >
> > > 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/[email protected]/
>
> 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 <[email protected]>