This patch adds binding documentation for the Samsung S5K6A3(YX) raw image sensor. Signed-off-by: Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx> --- The binding of this sensors shows some issue in the generic video-interfaces binding. Namely The video bus type (serial MIPI CSI-2, parallel ITU-R BT.656, etc.) is being determined by the binding parser (v4l2-of.c) depending on what properties are found in an enddpoint node. Please have a look at the data-lanes property description. The sensor supports MIPI CSI-2 and SMIA CCP2 interfaces which both use one data lane. One data lane is everything this sensors supports. During our discussions on the generic bidings in the past I proposed to introduce a property in the endpoint node that would indicate what bus type (standard/protocol) is used, e.g. MIPI CSI-2, ITU-R BT.656, SMIA CCP2, etc. It was argued though that we can well determine bus type based on properties found in the endpoint node. So now in case of this sensor I'm not sure how it can be differentiated whether MIPI CSI-2 or CCP2 bus is used. There is no CCP2 specific generic properties yet. Anyway I'm not really happy there is no property like bus_type that would clearly indicate what data bus type is used. Then would would for instance not specify "data-lanes" in endpoint node just to differentiate between MIPI CSI-2 and the parallel busses. The main issue for this particular binding is that even with data-lanes = <1>; it is still impossible to figure out whether MIPI CSI-2 or SMIA CCP2 data bus is used. So how about introducing, e.g. a string type "bus_type" common property ? I'm considering starting a separate thread for discussing this. --- .../devicetree/bindings/media/samsung-s5k6a3.txt | 31 ++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 Documentation/devicetree/bindings/media/samsung-s5k6a3.txt diff --git a/Documentation/devicetree/bindings/media/samsung-s5k6a3.txt b/Documentation/devicetree/bindings/media/samsung-s5k6a3.txt new file mode 100644 index 0000000..a51fbe8 --- /dev/null +++ b/Documentation/devicetree/bindings/media/samsung-s5k6a3.txt @@ -0,0 +1,31 @@ +Samsung S5K6A3(YX) raw image sensor +--------------------------------- + +S5K6A3YX is a raw image sensor with MIPI CSI-2 and CCP2 image data interfaces +and CCI (I2C compatible) control bus. + +Required properties: + +- compatible : "samsung,s5k6a3yx"; +- reg : I2C slave address of the sensor; +- svdda-supply : core voltage supply; +- svddio-supply : I/O voltage supply; +- gpios : specifier of a GPIO connected to the RESET pin; +- clocks : should contain the sensor's EXTCLK clock specifier, from + the common clock bindings. +- clock-names : should contain "extclk" entry; + +Optional properties: + +- clock-frequency : the frequency at which the "extclk" clock should be + configured to operate, in Hz; if this property is not + specified default 24 MHz value will be used. + +The common video interfaces bindings (see video-interfaces.txt) should be +used to specify link to the image data receiver. The S5K6A3(YX) device +node should contain one 'port' child node with an 'endpoint' subnode. + +Following properties are valid for the endpoint node: + +- data-lanes : (optional) specifies MIPI CSI-2 data lanes as covered in + video-interfaces.txt. The sensor supports only one data lane. -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
