diff mbox series

[v2,2/4] dt-bindings: soc: amlogic: add meson-canvas documentation

Message ID 20180807220011.24436-3-maxi.jourdan@wanadoo.fr (mailing list archive)
State Not Applicable
Headers show
Series soc: amlogic: add meson-canvas | expand

Commit Message

Maxime Jourdan Aug. 7, 2018, 10 p.m. UTC
DT bindings doc for amlogic,meson-canvas

Signed-off-by: Maxime Jourdan <maxi.jourdan@wanadoo.fr>
---
 .../soc/amlogic/amlogic,meson-canvas.txt      | 36 +++++++++++++++++++
 1 file changed, 36 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt

Comments

Rob Herring (Arm) Aug. 13, 2018, 7:07 p.m. UTC | #1
On Wed, Aug 08, 2018 at 12:00:09AM +0200, Maxime Jourdan wrote:
> DT bindings doc for amlogic,meson-canvas
> 
> Signed-off-by: Maxime Jourdan <maxi.jourdan@wanadoo.fr>
> ---
>  .../soc/amlogic/amlogic,meson-canvas.txt      | 36 +++++++++++++++++++
>  1 file changed, 36 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
> 
> diff --git a/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt b/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
> new file mode 100644
> index 000000000000..5f0351717bee
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
> @@ -0,0 +1,36 @@
> +Amlogic Canvas
> +================================
> +
> +A canvas is a collection of metadata that describes a pixel buffer.
> +Those metadata include: width, height, phyaddr, wrapping, block mode
> +and endianness.
> +
> +Many IPs within Amlogic SoCs rely on canvas indexes to read/write pixel data
> +rather than use the phy addresses directly. For instance, this is the case for
> +the video decoders and the display.
> +
> +Amlogic SoCs have 256 canvas.
> +
> +Device Tree Bindings:
> +---------------------
> +
> +Canvas Provider
> +--------------------------
> +
> +Required properties:
> +- compatible: "amlogic,canvas"
> +
> +Parent node should have the following properties :
> +- compatible: "amlogic,gx-dmc-sysctrl", "syscon", "simple-mfd"

Is this documented somewhere? One child function is not a reason for an 
MFD and child nodes. And child nodes like this with no resources are 
unnecessary.

> +- reg: base address and size of the DMC system control register space.
> +
> +Example:
> +
> +sysctrl_DMC: system-controller@0 {
> +	compatible = "amlogic,gx-dmc-sysctrl", "syscon", "simple-mfd";
> +	reg = <0x0 0x0 0x0 0x1000>;
> +
> +	canvas: canvas-provider@0 {
> +		compatible = "amlogic,canvas";
> +	};
> +};
> -- 
> 2.18.0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe devicetree" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
Maxime Jourdan Aug. 14, 2018, 2:42 a.m. UTC | #2
2018-08-13 21:07 GMT+02:00 Rob Herring <robh@kernel.org>:
> On Wed, Aug 08, 2018 at 12:00:09AM +0200, Maxime Jourdan wrote:
>> DT bindings doc for amlogic,meson-canvas
>>
>> Signed-off-by: Maxime Jourdan <maxi.jourdan@wanadoo.fr>
>> ---
>>  .../soc/amlogic/amlogic,meson-canvas.txt      | 36 +++++++++++++++++++
>>  1 file changed, 36 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
>>
>> diff --git a/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt b/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
>> new file mode 100644
>> index 000000000000..5f0351717bee
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
>> @@ -0,0 +1,36 @@
>> +Amlogic Canvas
>> +================================
>> +
>> +A canvas is a collection of metadata that describes a pixel buffer.
>> +Those metadata include: width, height, phyaddr, wrapping, block mode
>> +and endianness.
>> +
>> +Many IPs within Amlogic SoCs rely on canvas indexes to read/write pixel data
>> +rather than use the phy addresses directly. For instance, this is the case for
>> +the video decoders and the display.
>> +
>> +Amlogic SoCs have 256 canvas.
>> +
>> +Device Tree Bindings:
>> +---------------------
>> +
>> +Canvas Provider
>> +--------------------------
>> +
>> +Required properties:
>> +- compatible: "amlogic,canvas"
>> +
>> +Parent node should have the following properties :
>> +- compatible: "amlogic,gx-dmc-sysctrl", "syscon", "simple-mfd"
>
> Is this documented somewhere? One child function is not a reason for an
> MFD and child nodes. And child nodes like this with no resources are
> unnecessary.
>

Hi Rob, this was done to follow the same path as other buses on the
platform that have sysctrls in order to provide regmaps to the
devices.

I can see how it's not really necessary here though, would it be okay
with you if I turned "canvas" into a simple bus subnode, using __iomem
in the device ?

>> +- reg: base address and size of the DMC system control register space.
>> +
>> +Example:
>> +
>> +sysctrl_DMC: system-controller@0 {
>> +     compatible = "amlogic,gx-dmc-sysctrl", "syscon", "simple-mfd";
>> +     reg = <0x0 0x0 0x0 0x1000>;
>> +
>> +     canvas: canvas-provider@0 {
>> +             compatible = "amlogic,canvas";
>> +     };
>> +};
>> --
>> 2.18.0
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe devicetree" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
Rob Herring (Arm) Aug. 14, 2018, 2:39 p.m. UTC | #3
On Mon, Aug 13, 2018 at 8:42 PM Maxime Jourdan <maxi.jourdan@wanadoo.fr> wrote:
>
> 2018-08-13 21:07 GMT+02:00 Rob Herring <robh@kernel.org>:
> > On Wed, Aug 08, 2018 at 12:00:09AM +0200, Maxime Jourdan wrote:
> >> DT bindings doc for amlogic,meson-canvas
> >>
> >> Signed-off-by: Maxime Jourdan <maxi.jourdan@wanadoo.fr>
> >> ---
> >>  .../soc/amlogic/amlogic,meson-canvas.txt      | 36 +++++++++++++++++++
> >>  1 file changed, 36 insertions(+)
> >>  create mode 100644 Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
> >>
> >> diff --git a/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt b/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
> >> new file mode 100644
> >> index 000000000000..5f0351717bee
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
> >> @@ -0,0 +1,36 @@
> >> +Amlogic Canvas
> >> +================================
> >> +
> >> +A canvas is a collection of metadata that describes a pixel buffer.
> >> +Those metadata include: width, height, phyaddr, wrapping, block mode
> >> +and endianness.
> >> +
> >> +Many IPs within Amlogic SoCs rely on canvas indexes to read/write pixel data
> >> +rather than use the phy addresses directly. For instance, this is the case for
> >> +the video decoders and the display.
> >> +
> >> +Amlogic SoCs have 256 canvas.
> >> +
> >> +Device Tree Bindings:
> >> +---------------------
> >> +
> >> +Canvas Provider
> >> +--------------------------
> >> +
> >> +Required properties:
> >> +- compatible: "amlogic,canvas"
> >> +
> >> +Parent node should have the following properties :
> >> +- compatible: "amlogic,gx-dmc-sysctrl", "syscon", "simple-mfd"
> >
> > Is this documented somewhere? One child function is not a reason for an
> > MFD and child nodes. And child nodes like this with no resources are
> > unnecessary.
> >
>
> Hi Rob, this was done to follow the same path as other buses on the
> platform that have sysctrls in order to provide regmaps to the
> devices.
>
> I can see how it's not really necessary here though, would it be okay
> with you if I turned "canvas" into a simple bus subnode, using __iomem
> in the device ?

That's a driver issue that has little to do with the binding. You can
create a regmap for any node, "syscon" just does that automagically
for you.

Rob
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt b/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
new file mode 100644
index 000000000000..5f0351717bee
--- /dev/null
+++ b/Documentation/devicetree/bindings/soc/amlogic/amlogic,meson-canvas.txt
@@ -0,0 +1,36 @@ 
+Amlogic Canvas
+================================
+
+A canvas is a collection of metadata that describes a pixel buffer.
+Those metadata include: width, height, phyaddr, wrapping, block mode
+and endianness.
+
+Many IPs within Amlogic SoCs rely on canvas indexes to read/write pixel data
+rather than use the phy addresses directly. For instance, this is the case for
+the video decoders and the display.
+
+Amlogic SoCs have 256 canvas.
+
+Device Tree Bindings:
+---------------------
+
+Canvas Provider
+--------------------------
+
+Required properties:
+- compatible: "amlogic,canvas"
+
+Parent node should have the following properties :
+- compatible: "amlogic,gx-dmc-sysctrl", "syscon", "simple-mfd"
+- reg: base address and size of the DMC system control register space.
+
+Example:
+
+sysctrl_DMC: system-controller@0 {
+	compatible = "amlogic,gx-dmc-sysctrl", "syscon", "simple-mfd";
+	reg = <0x0 0x0 0x0 0x1000>;
+
+	canvas: canvas-provider@0 {
+		compatible = "amlogic,canvas";
+	};
+};