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

From: Wu, Songjun
Date: Sat Jun 11 2016 - 23:04:51 EST




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>;
+ };
+ };
+};