On 21/02/14 16:42, Mark Rutland wrote: [...] >> +++ b/Documentation/devicetree/bindings/media/samsung-s5c73m3.txt >> @@ -0,0 +1,97 @@ >> +Samsung S5C73M3 8Mp camera ISP >> +------------------------------ >> + >> +The S5C73M3 camera ISP supports MIPI CSI-2 and parallel (ITU-R BT.656) video >> +data busses. The I2C bus is the main control bus and additionally the SPI bus >> +is used, mostly for transferring the firmware to and from the device. Two >> +slave device nodes corresponding to these control bus interfaces are required >> +and should be placed under respective bus controller nodes. > > So this has both an I2C interface and an SPI interface that are used at > the same time? Yes, both are needed. AFAIU SPI is added so the firmware upload is faster. >> +I2C slave device node >> +--------------------- >> + >> +Required properties: >> + >> +- compatible : "samsung,s5c73m3"; >> +- reg : I2C slave address of the sensor; >> +- vdd-int-supply : digital power supply (1.2V); >> +- vdda-supply : analog power supply (1.2V); >> +- vdd-reg-supply : regulator input power supply (2.8V); >> +- vddio-host-supply : host I/O power supply (1.8V to 2.8V); >> +- vddio-cis-supply : CIS I/O power supply (1.2V to 1.8V); >> +- vdd-af-supply : lens power supply (2.8V); >> +- xshutdown-gpios : specifier of GPIO connected to the XSHUTDOWN pin; >> +- standby-gpios : specifier of GPIO connected to the STANDBY pin; >> +- clocks : should contain list of phandle and clock specifier pairs >> + according to common clock bindings for the clocks described >> + in the clock-names property; >> +- clock-names : should contain "cis_extclk" entry for the CIS_EXTCLK clock; >> + >> +Optional properties: >> + >> +- clock-frequency : the frequency at which the "cis_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 from the S5C73M3 to an external image data receiver. The S5C73M3 >> +device node should contain one 'port' child node with an 'endpoint' subnode for >> +this purpose. The data link from a raw image sensor to the S5C73M3 can be >> +similarly specified, but it is optional since the S5C73M3 ISP and a raw image >> +sensor are usually inseparable and form a hybrid module. >> + >> +Following properties are valid for the endpoint node(s): >> + >> +endpoint subnode >> +---------------- >> + >> +- data-lanes : (optional) specifies MIPI CSI-2 data lanes as covered in >> + video-interfaces.txt. This sensor doesn't support data lane remapping >> + and physical lane indexes in subsequent elements of the array should >> + be only consecutive ascending values. >> + >> +SPI device node >> +--------------- >> + >> +Required properties: >> + >> +- compatible : "samsung,s5c73m3"; > > It might make sense to explicitly link these two nodes somehow, in case > multiple instances appear somewhere. However, that can come later in the > case of a multi-instance device, and isn't necessary now. I guess a phandle at the I2C slave device node, pointing to the SPI node and/or the other way around would do. I don't expect these devices to be used in multiple instances though and would prefer to address that when necessary. We could try and create a root node for this device with an interesting structure, if we wanted to go much into details. But it could get a bit complicated given the scheme the I2C/SPI bus binding are structured now. Presumably that's something that could be handled later with a different compatible string if required. >> +For more details see description of the SPI busses bindings >> +(../spi/spi-bus.txt) and bindings of a specific bus controller. >> + >> +Example: >> + >> +i2c@138A000000 { >> + ... >> + s5c73m3@3c { >> + compatible = "samsung,s5c73m3"; >> + reg = <0x3c>; >> + vdd-int-supply = <&buck9_reg>; >> + vdda-supply = <&ldo17_reg>; >> + vdd-reg-supply = <&cam_io_reg>; >> + vddio-host-supply = <&ldo18_reg>; >> + vddio-cis-supply = <&ldo9_reg>; >> + vdd-af-supply = <&cam_af_reg>; >> + clock-frequency = <24000000>; >> + clocks = <&clk 0>; >> + clock-names = "cis_extclk"; >> + reset-gpios = <&gpf1 3 1>; >> + standby-gpios = <&gpm0 1 1>; >> + port { >> + s5c73m3_ep: endpoint { >> + remote-endpoint = <&csis0_ep>; >> + data-lanes = <1 2 3 4>; >> + }; >> + }; >> + }; >> +}; >> + >> +spi@1392000 { >> + ... >> + s5c73m3_spi: s5c73m3 { > > Nit: this should have a 0 unit-address to match the reg. OK, I'll correct that. >> + compatible = "samsung,s5c73m3"; >> + reg = <0>; >> + ... >> + }; >> +}; > > Otherwise I don't see anything problematic about the binding. > > Acked-by: Mark Rutland <mark.rutland@xxxxxxx> Thanks for the review. -- Regards, Sylwester -- 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