Re: [PATCH v4 2/2] [media] atmel-isc: DT binding for Image Sensor Controller driver

[Wu, Songjun]

On 6/9/2016 05:57, Boris Brezillon wrote:
> On Tue, 7 Jun 2016 15:11:53 +0800
> Songjun Wu <songjun.wu@xxxxxxxxx> wrote:
>
> > DT binding documentation for ISC driver.
> >
> > Signed-off-by: Songjun Wu <songjun.wu@xxxxxxxxx>
> > ---
> >
> > Changes in v4:
> > - Remove the isc clock nodes.
> >
> > Changes in v3:
> > - Remove the 'atmel,sensor-preferred'.
> > - Modify the isc clock node according to the Rob's remarks.
> >
> > Changes in v2:
> > - Remove the unit address of the endpoint.
> > - Add the unit address to the clock node.
> > - Avoid using underscores in node names.
> > - Drop the "0x" in the unit address of the i2c node.
> > - Modify the description of 'atmel,sensor-preferred'.
> > - Add the description for the ISC internal clock.
> >
> >  .../devicetree/bindings/media/atmel-isc.txt        | 69 ++++++++++++++++++++++
> >  1 file changed, 69 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/media/atmel-isc.txt
> >
> > diff --git a/Documentation/devicetree/bindings/media/atmel-isc.txt b/Documentation/devicetree/bindings/media/atmel-isc.txt
> > new file mode 100644
> > index 0000000..3f83524
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/media/atmel-isc.txt
> > @@ -0,0 +1,69 @@
> > +Atmel Image Sensor Controller (ISC)
> > +----------------------------------------------
> > +
> > +Required properties for ISC:
> > +- compatible
> > +	Must be "atmel,sama5d2-isc".
> > +- reg
> > +	Physical base address and length of the registers set for the device.
> > +- interrupts
> > +	Should contain IRQ line for the ISC.
> > +- clocks
> > +	List of clock specifiers, corresponding to entries in
> > +	the clock-names property;
> > +	Please refer to clock-bindings.txt.
> > +- clock-names
> > +	Required elements: "hclock".
> > +- #clock-cells
> > +	Should be 0.
> > +- clock-output-names
> > +	Should contain the name of the clock driving the sensor master clock.
> > +- pinctrl-names, pinctrl-0
> > +	Please refer to pinctrl-bindings.txt.
> > +
> > +
> > +ISC supports a single port node with parallel bus. It should contain one
> > +'port' child node with child 'endpoint' node. Please refer to the bindings
> > +defined in Documentation/devicetree/bindings/media/video-interfaces.txt.
> > +
> > +Example:
> > +isc: isc@f0008000 {
> > +	compatible = "atmel,sama5d2-isc";
> > +	reg = <0xf0008000 0x4000>;
> > +	interrupts = <46 IRQ_TYPE_LEVEL_HIGH 5>;
> > +	clocks = <&isc_clk>, <&iscck>, <&isc_gclk>;
> > +	clock-names = "hclock";
>
> You have 3 clocks here and only one name. Are you sure this example is
> actually working?
The isc_clk is mandatory, but the other two clocks are optional, so I 
did not give their name. This example is tested.
Should I add the name for the other two clocks?

> > +	#clock-cells = <0>;
> > +	clock-output-names = "isc-mck";
> > +
> > +	port {
> > +		#address-cells = <1>;
> > +		#size-cells = <0>;
> > +
> > +		isc_0: endpoint {
> > +			remote-endpoint = <&ov7740_0>;
> > +			hsync-active = <1>;
> > +			vsync-active = <0>;
> > +			pclk-sample = <1>;
> > +		};
> > +	};
> > +
> > +
> > +};
> > +
> > +i2c1: i2c@fc028000 {
> > +	ov7740: camera@21 {
> > +	compatible = "ovti,ov7740";
> > +	reg = <0x21>;
> > +
> > +	clocks = <&isc>;
> > +	clock-names = "xvclk";
> > +	assigned-clocks = <&isc>;
> > +	assigned-clock-rates = <24000000>;
> > +
> > +	port {
> > +		ov7740_0: endpoint {
> > +			remote-endpoint = <&isc_0>;
> > +		};
> > +	};
> > +};