diff mbox

[v3,2/2] dt-bindings: drm/bridge: Document Cadence DSI bridge bindings

Message ID 20170831155519.3704-2-boris.brezillon@free-electrons.com (mailing list archive)
State New, archived
Headers show

Commit Message

Boris BREZILLON Aug. 31, 2017, 3:55 p.m. UTC
Document the bindings used for the Cadence DSI bridge.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
Changes in v3:
- Fix clock names in the example
- Document how to represent DSI devices that are controller through
  an external bus like I2C or SPI

Changes in v2:
- None
---
 .../bindings/display/bridge/cdns,dsi.txt           | 109 +++++++++++++++++++++
 1 file changed, 109 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt

Comments

Andrzej Hajda Sept. 1, 2017, 6:28 a.m. UTC | #1
On 31.08.2017 17:55, Boris Brezillon wrote:
> Document the bindings used for the Cadence DSI bridge.
>
> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> ---
> Changes in v3:
> - Fix clock names in the example
> - Document how to represent DSI devices that are controller through
>   an external bus like I2C or SPI
>
> Changes in v2:
> - None
> ---
>  .../bindings/display/bridge/cdns,dsi.txt           | 109 +++++++++++++++++++++
>  1 file changed, 109 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
>
> diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
> new file mode 100644
> index 000000000000..c70008bd8c0d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
> @@ -0,0 +1,109 @@
> +Cadence DSI bridge
> +==================
> +
> +The Cadence DSI bridge is a DPI to DSI bridge supporting up to 4 DSI lanes.
> +
> +Required properties:
> +- compatible: should be set to "cdns,dsi-1.3.1".
> +- reg: physical base address and length of the controller's registers.
> +- interrupts: interrupt line connected to the DSI bridge.
> +- clocks: DSI bridge clocks.
> +- clock-names: must contain "pclk" and "sysclk".
> +- phys: phandle link to the MIPI D-PHY controller.
> +- phy-names: must contain "dphy".
> +- #address-cells: must be set to 1.
> +- #size-cells: must be set to 0.
> +
> +Required subnodes:
> +- ports: Ports as described in Documentation/devicetree/bindings/graph.txt.
> +  2 ports are available:
> +  * port 0: this port is only needed if some of your DSI devices are
> +	    controlled through  an external bus like I2C or SPI. Can have at
> +	    most 4 endpoints. The endpoint number is directly encoding the
> +	    DSI virtual channel used by this device.
> +  * port 1: represents the DPI input.
> +  Other ports will be added later to support the new kind of inputs.

I think usual practice is to use lower numbers for input ports, higher
for output ports.
Is there a reason to do it this way?

Regards
Andrzej

> +
> +- one subnode per DSI device connected on the DSI bus. Each DSI device should
> +  contain a reg property encoding its virtual channel.
> +
> +Example:
> +
> +	dsi0: dsi@fd0c0000 {
> +		compatible = "cdns,dsi-1.3.1";
> +		reg = <0x0 0xfd0c0000 0x0 0x1000>;
> +		clocks = <&pclk>, <&sysclk>;
> +		clock-names = "pclk", "sysclk";
> +		interrupts = <1>;
> +		phys = <&dphy1>;
> +		phy-names = "dphy";
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +
> +		ports {
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +
> +			port@1 {
> +				reg = <1>;
> +				dsi0_dpi_input: endpoint {
> +					remote-endpoint = <&xxx_dpi_output>;
> +				};
> +			};
> +		};
> +
> +		panel: dsi-dev@0 {
> +			compatible = "<vendor,panel>";
> +			reg = <0>;
> +		};
> +	};
> +
> +or
> +
> +	dsi0: dsi@fd0c0000 {
> +		compatible = "cdns,dsi";
> +		reg = <0x0 0xfd0c0000 0x0 0x1000>;
> +		clocks = <&pclk>, <&sysclk>;
> +		clock-names = "pclk", "sysclk";
> +		interrupts = <1>;
> +		phys = <&dphy1>;
> +		phy-names = "dphy";
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +
> +		ports {
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +
> +			port@0 {
> +				reg = <0>;
> +				#address-cells = <1>;
> +				#size-cells = <0>;
> +
> +				dsi0_output: endpoint@0 {
> +					reg = <0>;
> +					remote-endpoint = <&dsi_panel_input>;
> +				};
> +			};
> +
> +			port@1 {
> +				reg = <1>;
> +				dsi0_dpi_input: endpoint {
> +					remote-endpoint = <&xxx_dpi_output>;
> +				};
> +			};
> +		};
> +	};
> +
> +	i2c@xxx {
> +		panel: panel@59 {
> +			compatible = "<vendor,panel>";
> +			reg = <0x59>;
> +
> +			port {
> +				dsi_panel_input: endpoint {
> +					remote-endpoint = <&dsi0_output>;
> +				};
> +			};
> +		};
> +	};
Boris BREZILLON Sept. 1, 2017, 7:06 a.m. UTC | #2
Hi Andrzej,

On Fri, 01 Sep 2017 08:28:13 +0200
Andrzej Hajda <a.hajda@samsung.com> wrote:

> On 31.08.2017 17:55, Boris Brezillon wrote:
> > Document the bindings used for the Cadence DSI bridge.
> >
> > Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> > ---
> > Changes in v3:
> > - Fix clock names in the example
> > - Document how to represent DSI devices that are controller through
> >   an external bus like I2C or SPI
> >
> > Changes in v2:
> > - None
> > ---
> >  .../bindings/display/bridge/cdns,dsi.txt           | 109 +++++++++++++++++++++
> >  1 file changed, 109 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
> >
> > diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
> > new file mode 100644
> > index 000000000000..c70008bd8c0d
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
> > @@ -0,0 +1,109 @@
> > +Cadence DSI bridge
> > +==================
> > +
> > +The Cadence DSI bridge is a DPI to DSI bridge supporting up to 4 DSI lanes.
> > +
> > +Required properties:
> > +- compatible: should be set to "cdns,dsi-1.3.1".
> > +- reg: physical base address and length of the controller's registers.
> > +- interrupts: interrupt line connected to the DSI bridge.
> > +- clocks: DSI bridge clocks.
> > +- clock-names: must contain "pclk" and "sysclk".
> > +- phys: phandle link to the MIPI D-PHY controller.
> > +- phy-names: must contain "dphy".
> > +- #address-cells: must be set to 1.
> > +- #size-cells: must be set to 0.
> > +
> > +Required subnodes:
> > +- ports: Ports as described in Documentation/devicetree/bindings/graph.txt.
> > +  2 ports are available:
> > +  * port 0: this port is only needed if some of your DSI devices are
> > +	    controlled through  an external bus like I2C or SPI. Can have at
> > +	    most 4 endpoints. The endpoint number is directly encoding the
> > +	    DSI virtual channel used by this device.
> > +  * port 1: represents the DPI input.
> > +  Other ports will be added later to support the new kind of inputs.  
> 
> I think usual practice is to use lower numbers for input ports, higher
> for output ports.
> Is there a reason to do it this way?

The main reason I did that is because we only have one output port and
can have 1, 2 or 3 input ports: one is the DPI and the 2 others are
called SDI (some kind of serial input). I thought it would be better to
have all inputs using contiguous port numbers, and if we put inputs
first that means having a hole between the input and output port (port 0
would be the DPI input and port 3 the DSI output).

Honestly, that's just a detail, so if you prefer to have the input
ports start at 0 I'm fine with that.

Regards,

Boris
Andrzej Hajda Sept. 1, 2017, 7:26 a.m. UTC | #3
On 01.09.2017 09:06, Boris Brezillon wrote:
> Hi Andrzej,
>
> On Fri, 01 Sep 2017 08:28:13 +0200
> Andrzej Hajda <a.hajda@samsung.com> wrote:
>
>> On 31.08.2017 17:55, Boris Brezillon wrote:
>>> Document the bindings used for the Cadence DSI bridge.
>>>
>>> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
>>> ---
>>> Changes in v3:
>>> - Fix clock names in the example
>>> - Document how to represent DSI devices that are controller through
>>>   an external bus like I2C or SPI
>>>
>>> Changes in v2:
>>> - None
>>> ---
>>>  .../bindings/display/bridge/cdns,dsi.txt           | 109 +++++++++++++++++++++
>>>  1 file changed, 109 insertions(+)
>>>  create mode 100644 Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
>>> new file mode 100644
>>> index 000000000000..c70008bd8c0d
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
>>> @@ -0,0 +1,109 @@
>>> +Cadence DSI bridge
>>> +==================
>>> +
>>> +The Cadence DSI bridge is a DPI to DSI bridge supporting up to 4 DSI lanes.
>>> +
>>> +Required properties:
>>> +- compatible: should be set to "cdns,dsi-1.3.1".
>>> +- reg: physical base address and length of the controller's registers.
>>> +- interrupts: interrupt line connected to the DSI bridge.
>>> +- clocks: DSI bridge clocks.
>>> +- clock-names: must contain "pclk" and "sysclk".
>>> +- phys: phandle link to the MIPI D-PHY controller.
>>> +- phy-names: must contain "dphy".
>>> +- #address-cells: must be set to 1.
>>> +- #size-cells: must be set to 0.
>>> +
>>> +Required subnodes:
>>> +- ports: Ports as described in Documentation/devicetree/bindings/graph.txt.
>>> +  2 ports are available:
>>> +  * port 0: this port is only needed if some of your DSI devices are
>>> +	    controlled through  an external bus like I2C or SPI. Can have at
>>> +	    most 4 endpoints. The endpoint number is directly encoding the
>>> +	    DSI virtual channel used by this device.
>>> +  * port 1: represents the DPI input.
>>> +  Other ports will be added later to support the new kind of inputs.  
>> I think usual practice is to use lower numbers for input ports, higher
>> for output ports.
>> Is there a reason to do it this way?
> The main reason I did that is because we only have one output port and
> can have 1, 2 or 3 input ports: one is the DPI and the 2 others are
> called SDI (some kind of serial input). I thought it would be better to
> have all inputs using contiguous port numbers, and if we put inputs
> first that means having a hole between the input and output port (port 0
> would be the DPI input and port 3 the DSI output).
>
> Honestly, that's just a detail, so if you prefer to have the input
> ports start at 0 I'm fine with that.

No serious preferences, just curiosity. In fact port numbering schema is
private thing of the device node.

Regards
Andrzej

>
> Regards,
>
> Boris
>
>
>
>
>
Rob Herring (Arm) Sept. 12, 2017, 4:03 p.m. UTC | #4
On Thu, Aug 31, 2017 at 05:55:19PM +0200, Boris Brezillon wrote:
> Document the bindings used for the Cadence DSI bridge.
> 
> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> ---
> Changes in v3:
> - Fix clock names in the example
> - Document how to represent DSI devices that are controller through
>   an external bus like I2C or SPI
> 
> Changes in v2:
> - None
> ---
>  .../bindings/display/bridge/cdns,dsi.txt           | 109 +++++++++++++++++++++
>  1 file changed, 109 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt

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

Patch

diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
new file mode 100644
index 000000000000..c70008bd8c0d
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
@@ -0,0 +1,109 @@ 
+Cadence DSI bridge
+==================
+
+The Cadence DSI bridge is a DPI to DSI bridge supporting up to 4 DSI lanes.
+
+Required properties:
+- compatible: should be set to "cdns,dsi-1.3.1".
+- reg: physical base address and length of the controller's registers.
+- interrupts: interrupt line connected to the DSI bridge.
+- clocks: DSI bridge clocks.
+- clock-names: must contain "pclk" and "sysclk".
+- phys: phandle link to the MIPI D-PHY controller.
+- phy-names: must contain "dphy".
+- #address-cells: must be set to 1.
+- #size-cells: must be set to 0.
+
+Required subnodes:
+- ports: Ports as described in Documentation/devicetree/bindings/graph.txt.
+  2 ports are available:
+  * port 0: this port is only needed if some of your DSI devices are
+	    controlled through  an external bus like I2C or SPI. Can have at
+	    most 4 endpoints. The endpoint number is directly encoding the
+	    DSI virtual channel used by this device.
+  * port 1: represents the DPI input.
+  Other ports will be added later to support the new kind of inputs.
+
+- one subnode per DSI device connected on the DSI bus. Each DSI device should
+  contain a reg property encoding its virtual channel.
+
+Example:
+
+	dsi0: dsi@fd0c0000 {
+		compatible = "cdns,dsi-1.3.1";
+		reg = <0x0 0xfd0c0000 0x0 0x1000>;
+		clocks = <&pclk>, <&sysclk>;
+		clock-names = "pclk", "sysclk";
+		interrupts = <1>;
+		phys = <&dphy1>;
+		phy-names = "dphy";
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@1 {
+				reg = <1>;
+				dsi0_dpi_input: endpoint {
+					remote-endpoint = <&xxx_dpi_output>;
+				};
+			};
+		};
+
+		panel: dsi-dev@0 {
+			compatible = "<vendor,panel>";
+			reg = <0>;
+		};
+	};
+
+or
+
+	dsi0: dsi@fd0c0000 {
+		compatible = "cdns,dsi";
+		reg = <0x0 0xfd0c0000 0x0 0x1000>;
+		clocks = <&pclk>, <&sysclk>;
+		clock-names = "pclk", "sysclk";
+		interrupts = <1>;
+		phys = <&dphy1>;
+		phy-names = "dphy";
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				dsi0_output: endpoint@0 {
+					reg = <0>;
+					remote-endpoint = <&dsi_panel_input>;
+				};
+			};
+
+			port@1 {
+				reg = <1>;
+				dsi0_dpi_input: endpoint {
+					remote-endpoint = <&xxx_dpi_output>;
+				};
+			};
+		};
+	};
+
+	i2c@xxx {
+		panel: panel@59 {
+			compatible = "<vendor,panel>";
+			reg = <0x59>;
+
+			port {
+				dsi_panel_input: endpoint {
+					remote-endpoint = <&dsi0_output>;
+				};
+			};
+		};
+	};