[PATCH 5/9] Doc/DT: Add DT binding documentation for MIPI DPI Panel

Add DT binding documentation for MIPI DPI Panel.

Signed-off-by: Tomi Valkeinen <redacted>
Reviewed-by: Archit Taneja <redacted>
---
 .../devicetree/bindings/video/panel-dpi.txt        | 43 ++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/video/panel-dpi.txt

diff --git a/Documentation/devicetree/bindings/video/panel-dpi.txt b/Documentation/devicetree/bindings/video/panel-dpi.txt
new file mode 100644
index 000000000000..72636c6f1c67
--- /dev/null
+++ b/Documentation/devicetree/bindings/video/panel-dpi.txt

@@ -0,0 +1,43 @@
+Generic MIPI DPI Panel
+===========
+
+Required properties:
+- compatible: "panel-dpi"
+
+Optional properties:
+- label: a symbolic name for the panel
+- gpios: panel enable gpio and backlight enable gpio
+
+Required nodes:
+- "panel-timing" containing video timings
+  (Documentation/devicetree/bindings/video/display-timing.txt)
+- Video port for DPI input
+
+Example
+-------
+
+lcd0: display@0 {
+        compatible = "samsung,lte430wq-f0c", "panel-dpi";
+        label = "lcd";
+
+        lcd_in: endpoint {
+                remote-endpoint = <&dpi_out>;
+        };
+
+        panel-timing {
+                clock-frequency = <9200000>;
+                hactive = <480>;
+                vactive = <272>;
+                hfront-porch = <8>;
+                hback-porch = <4>;
+                hsync-len = <41>;
+                vback-porch = <2>;
+                vfront-porch = <4>;
+                vsync-len = <10>;
+
+                hsync-active = <0>;
+                vsync-active = <0>;
+                de-active = <1>;
+                pixelclk-active = <1>;
+        };
+};

-- 
1.8.3.2

Am Freitag, den 28.02.2014, 14:20 +0200 schrieb Tomi Valkeinen:

I don't see anything MIPI specific here. Couldn't this be added to the
existing simple-panel binding?

regards
Philipp

On 28/02/14 15:40, Philipp Zabel wrote:

Am Freitag, den 28.02.2014, 14:20 +0200 schrieb Tomi Valkeinen:

quoted

Add DT binding documentation for MIPI DPI Panel.

Signed-off-by: Tomi Valkeinen <redacted>
Reviewed-by: Archit Taneja <redacted>
---
 .../devicetree/bindings/video/panel-dpi.txt        | 43 ++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/video/panel-dpi.txt

diff --git a/Documentation/devicetree/bindings/video/panel-dpi.txt b/Documentation/devicetree/bindings/video/panel-dpi.txt
new file mode 100644
index 000000000000..72636c6f1c67
--- /dev/null
+++ b/Documentation/devicetree/bindings/video/panel-dpi.txt

@@ -0,0 +1,43 @@
+Generic MIPI DPI Panel
+======================
+
+Required properties:
+- compatible: "panel-dpi"
+
+Optional properties:
+- label: a symbolic name for the panel
+- gpios: panel enable gpio and backlight enable gpio
+
+Required nodes:
+- "panel-timing" containing video timings
+  (Documentation/devicetree/bindings/video/display-timing.txt)
+- Video port for DPI input

I don't see anything MIPI specific here. Couldn't this be added to the
existing simple-panel binding?

Hmm, well, the simple-panel bindings doesn't define video ports, and not
even a common compatible property.

 Tomi

Hi Tomi,

Thank you for the patch.

On Friday 28 February 2014 14:20:12 Tomi Valkeinen wrote:

While integrated in the panel module, the backlight is a separate piece of 
hardware, which could be controlled through other means (I2C for instance). 
Wouldn't it be better to add an explicit DT node for the backlight device and 
reference that node from the panel node ?

-- 
Regards,

Laurent Pinchart

On 17/03/14 16:19, Laurent Pinchart wrote:

quoted

+Generic MIPI DPI Panel
+======================
+
+Required properties:
+- compatible: "panel-dpi"
+
+Optional properties:
+- label: a symbolic name for the panel
+- gpios: panel enable gpio and backlight enable gpio

While integrated in the panel module, the backlight is a separate piece of 
hardware, which could be controlled through other means (I2C for instance). 
Wouldn't it be better to add an explicit DT node for the backlight device and 
reference that node from the panel node ?

Yes, I agree, but do we have the infrastructure or bindings for that?

Ah, I see we now do have a gpio-backlight driver, but it doesn't have DT
bindings.

 Tomi

On 18/03/14 08:41, Tomi Valkeinen wrote:

On 17/03/14 16:19, Laurent Pinchart wrote:

quoted

quoted

+Generic MIPI DPI Panel
+======================
+
+Required properties:
+- compatible: "panel-dpi"
+
+Optional properties:
+- label: a symbolic name for the panel
+- gpios: panel enable gpio and backlight enable gpio

While integrated in the panel module, the backlight is a separate piece of 
hardware, which could be controlled through other means (I2C for instance). 
Wouldn't it be better to add an explicit DT node for the backlight device and 
reference that node from the panel node ?

Yes, I agree, but do we have the infrastructure or bindings for that?

Ah, I see we now do have a gpio-backlight driver, but it doesn't have DT
bindings.

Seems there's a patch from Denis Carikli for this, which will probably
be merged for 3.15.

I realized I don't actually use panel-dpi at the moment in my OMAP DSS
DT series, as I dropped the board changes that used panel-dpi. So I'll
drop panel-dpi bindings from my series, and the backlight for panel-dpi
can then be fixed for 3.16.

 Tomi