Re: [PATCH v11 3/5] dt-bindings: drm/bridge: Document sn65dsi86 bridge bindings

On 2018-06-15 12:53, Andrzej Hajda wrote:

On 15.06.2018 08:43, Sandeep Panda wrote:

quoted

Document the bindings used for the sn65dsi86 DSI to eDP bridge.

Changes in v1:
 - Rephrase the dt-binding descriptions to be more inline with existing
   bindings (Andrzej Hajda).
 - Add missing dt-binding that are parsed by corresponding driver
   (Andrzej Hajda).

Changes in v2:
 - Remove edp panel specific dt-binding entries. Only keep bridge
   specific entries (Sean Paul).
 - Remove custom-modes dt entry since its usage is removed from driver also (Sean Paul).
 - Remove is-pluggable dt entry since this will not be needed anymore (Sean Paul).

Changes in v3:
 - Remove irq-gpio dt entry and instead populate is an interrupt
   property (Rob Herring).

Changes in v4:
 - Add link to bridge chip datasheet (Stephen Boyd)
 - Add vpll and vcc regulator supply bindings (Stephen Boyd)
 - Add ref clk optional dt binding (Stephen Boyd)
 - Add gpio-controller optional dt binding (Stephen Boyd)

Changes in v5:
 - Use clock property to specify the input refclk (Stephen Boyd).
 - Update gpio cell and pwm cell numbers (Stephen Boyd).

Changes in v6:
 - Add property to mention the lane mapping scheme and polarity inversion
   (Stephen Boyd).

Changes in v7:
 - Detail description of lane mapping scheme dt property (Andrzej
   Hajda/ Rob Herring).
 - Removed HDP gpio binding, since the bridge uses IRQ signal to
   determine HPD, and IRQ property is already documented in binding.

Changes in v8:
 - Removed unnecessary explanation of lane mapping and polarity dt
   property, since these are already explained in media/video-interface
   dt binidng (Rob Herring).

Changes in v9:
 - Avoid putting re-definition of lane mapping and polarity dt binding
   (Rob Herring).

Signed-off-by: Sandeep Panda <redacted>
---
 .../bindings/display/bridge/ti,sn65dsi86.txt       | 87 ++++++++++++++++++++++
 1 file changed, 87 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt

diff --git a/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt b/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt
new file mode 100644
index 0000000..507efbb
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt

@@ -0,0 +1,87 @@
+SN65DSI86 DSI to eDP bridge chip
+--------------------------------
+
+This is the binding for Texas Instruments SN65DSI86 bridge.
+http://www.ti.com/general/docs/lit/getliterature.tsp?genericPartNumber=sn65dsi86&fileType=pdf
+
+Required properties:
+- compatible: Must be "ti,sn65dsi86"
+- reg: i2c address of the chip, 0x2d as per datasheet
+- enable-gpios: OF device-tree gpio specification for bridge_en pin (active high)
+
+- vccio-supply: A 1.8V supply that powers up the digital IOs.
+- vpll-supply: A 1.8V supply that powers up the displayport PLL.
+- vcca-supply: A 1.2V supply that powers up the analog circuits.
+- vcc-supply: A 1.2V supply that powers up the digital core.

Since there are only two voltage levels (1.8 and 1.2) and power on/off
sequence does not require specific order I guess you could merge
supplies with the same level, but this is just an idea, up to you.
For example you can drop (or make optional) vpll-supply and vcca-supply.

quoted

+

Since the bridge datasheet mentions about 4 different power supplies and there
was also comment from other reviewers to keep all of them so i have put it like this.
Also this will help in scenarios where board design has 4 different sources for these 4
power supplies.

quoted

+Optional properties:
+- interrupts: Specifier for the SN65DSI86 interrupt line.

or interrupts-extended

quoted

+
+- ddc-i2c-bus: phandle of the I2C controller used for DDC EDID probing
+
+- gpio-controller: Marks the device has a GPIO controller.
+- #gpio-cells    : Should be two. The first cell is the pin number and
+                   the second cell is used to specify flags.
+                   See ../../gpio/gpio.txt for more information.
+- #pwm-cells : Should be one. See ../../pwm/pwm.txt for description of
+               the cell formats.
+
+- clock-names: should be "refclk"
+- clocks: Specification for input reference clock. The reference
+	  clock rate must be 12 MHz, 19.2 MHz, 26 MHz, 27 MHz or 38.4 MHz.
+
+- data-lanes: See ../../media/video-interface.txt
+- lane-polarities: See ../../media/video-interface.txt

Either you should describe which port these properties are related to,
either put them into endpoint node. According to
./../media/video-interface.txt only the latter is correct.

Data lane and lane-polarity is applicable to both DSI and eDP interface. I have
updated the same in ../../media/video-interface.txt. Do you want to explicitly
mention here that this property is for eDP data lanes mapping?

quoted

+
+Required nodes:
+This device has two video ports. Their connections are modelled using the
+OF graph bindings specified in Documentation/devicetree/bindings/graph.txt.
+
+- Video port 0 for DSI input
+- Video port 1 for eDP output
+
+Example
+-------
+
+edp-bridge@2d {
+	compatible = "ti,sn65dsi86";
+	#address-cells = <1>;
+	#size-cells = <0>;
+	reg = <0x2d>;
+
+	enable-gpios = <&msmgpio 33 GPIO_ACTIVE_HIGH>;
+	interrupt-parent = <&gpio3>;
+	interrupts = <4 IRQ_TYPE_EDGE_FALLING>;

In case of non-default interrupt parent interrupts-extended is more
compact/convenient - you can drop interrupt-parent property:
    interrupts-extended =  <&gpio3 4 IRQ_TYPE_EDGE_FALLING>;

Ok. will update in next patch.

quoted

+
+	vccio-supply = <&pm8916_l17>;
+	vcca-supply = <&pm8916_l6>;
+	vpll-supply = <&pm8916_l17>;
+	vcc-supply = <&pm8916_l6>;
+
+	clock-names = "refclk";
+	clocks = <&input_refclk>;
+
+	data-lanes = <2 1 3 0>;
+	lane-polarities = <0 1 0 1>;

And this should be fixed as well.

Ok i will move these to edp out endpoint node.

quoted

+
+	ports {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		port@0 {
+			reg = <0>;
+
+ 			edp_bridge_in: endpoint {
+				remote-endpoint = <&dsi_out>;
+			};
+		};
+
+		port@1 {
+			reg = <1>;
+
+			edp_bridge_out: endpoint {
+				remote-endpoint = <&edp_panel_in>;
+			};
+		};
+	};
+}

_______________________________________________
Freedreno mailing list
Freedreno@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/freedreno