Hi Rob,

On Wed, Nov 01, 2017 at 04:51:57PM -0500, Rob Herring wrote:

On Tue, Oct 31, 2017 at 09:11:44AM +0800, Wenyou Yang wrote:

quoted

Add the device tree binding documentation for the ov7740 sensor driver.

Signed-off-by: Wenyou Yang <redacted>
---

Changes in v4: None
Changes in v3:
 - Explicitly document the "remote-endpoint" property.

Changes in v2: None

 .../devicetree/bindings/media/i2c/ov7740.txt       | 47 ++++++++++++++++++++++
 1 file changed, 47 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/i2c/ov7740.txt

diff --git a/Documentation/devicetree/bindings/media/i2c/ov7740.txt b/Documentation/devicetree/bindings/media/i2c/ov7740.txt
new file mode 100644
index 000000000000..af781c3a5f0e
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/i2c/ov7740.txt

@@ -0,0 +1,47 @@
+* Omnivision OV7740 CMOS image sensor
+
+The Omnivision OV7740 image sensor supports multiple output image
+size, such as VGA, and QVGA, CIF and any size smaller. It also
+supports the RAW RGB and YUV output formats.
+
+The common video interfaces bindings (see video-interfaces.txt) should
+be used to specify link to the image data receiver. The OV7740 device
+node should contain one 'port' child node with an 'endpoint' subnode.
+
+Required Properties:
+- compatible:	"ovti,ov7740".
+- reg:		I2C slave address of the sensor.
+- clocks:	Reference to the xvclk input clock.
+- clock-names:	"xvclk".
+
+Optional Properties:
+- reset-gpios: Rreference to the GPIO connected to the reset_b pin,
+  if any. Active low with pull-ip resistor.
+- powerdown-gpios: Reference to the GPIO connected to the pwdn pin,
+  if any. Active high with pull-down resistor.
+
+Endpoint node mandatory properties:
+- remote-endpoint: A phandle to the bus receiver's endpoint node.

This is not really necessary. What's required is documenting how many 
ports and how many endpoints for each port which you have above.

I actually requested adding that as the practice, as far as I've understood
it, has been to document all properties relevant for the hardware (apart
from things such as assigned-clocks etc.).

The port and endpoints have been elaborated above and I think that should
be fine as-is.

The graph bindings document (referred by video-interfaces.txt) the
remote-endpoint property in an endpoint as an optional property, however
you can't really use the sensor if it's not connected to anything. The same
goes for video-interfaces.txt: remote-endpoint in an endpoint is optional.

I have no objections removing remote-endpoint here, though, if you think
it's not relevant here.

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus at iki.fi