Hi Ramesh,
Thank you for the patch.
On Tuesday 07 Feb 2017 15:02:32 Ramesh Shanmugasundaram wrote:
> Add device tree binding documentation for MAX2175 Rf to bits tuner
> device.
>
> Signed-off-by: Ramesh Shanmugasundaram
> <ramesh.shanmugasundaram@xxxxxxxxxxxxxx> ---
> .../devicetree/bindings/media/i2c/max2175.txt | 61 +++++++++++++++++++
> .../devicetree/bindings/property-units.txt | 1 +
> 2 files changed, 62 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/media/i2c/max2175.txt
>
> diff --git a/Documentation/devicetree/bindings/media/i2c/max2175.txt
> b/Documentation/devicetree/bindings/media/i2c/max2175.txt new file mode
> 100644
> index 0000000..f591ab4
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/i2c/max2175.txt
> @@ -0,0 +1,61 @@
> +Maxim Integrated MAX2175 RF to Bits tuner
> +-----------------------------------------
> +
> +The MAX2175 IC is an advanced analog/digital hybrid-radio receiver with
> +RF to Bits® front-end designed for software-defined radio solutions.
> +
> +Required properties:
> +--------------------
> +- compatible: "maxim,max2175" for MAX2175 RF-to-bits tuner.
> +- clocks: phandle to the fixed xtal clock.
> +- clock-names: name of the fixed xtal clock.
I would mention that the name has to be "xtal". Maybe something like
- clock-names: name of the fixed xtal clock, shall be "xtal".
> +- port: child port node of a tuner that defines the local and remote
> + endpoints. The remote endpoint is assumed to be an SDR device
> + that is capable of receiving the digital samples from the tuner.
You should refer to the OF graphs bindings here. How about the following to
document the port node ?
- port: child port node corresponding to the I2S output, in accordance with
the video interface bindings defined in
Documentation/devicetree/bindings/media/video-interfaces.txt. The port node
must contain at least one endpoint.
> +Optional properties:
> +--------------------
> +- maxim,slave : phandle to the master tuner if it is a slave.
This
> + is used to define two tuners in diversity mode
> + (1 master, 1 slave). By default each tuner is an
> + individual master.
It seems weird to me to name a property "slave" when it points to the master
tuner. Shouldn't it be named "maxim,master" ?
> +- maxim,refout-load-pF: load capacitance value (in pF) on reference
> + output drive level. The possible load values are
> + 0 (default - refout disabled)
> + 10
> + 20
> + 30
> + 40
> + 60
> + 70
> +- maxim,am-hiz : empty property indicates AM Hi-Z filter path
is
> + selected for AM antenna input. By default this
> + filter path is not used.
Isn't this something that should be selected at runtime through a control ? Or
does the hardware design dictate whether the filter has to be used or must not
be used ?
> +Example:
> +--------
> +
> +Board specific DTS file
> +
> +/* Fixed XTAL clock node */
> +maxim_xtal: clock {
> + compatible = "fixed-clock";
> + #clock-cells = <0>;
> + clock-frequency = <36864000>;
> +};
> +
> +/* A tuner device instance under i2c bus */
> +max2175_0: tuner@60 {
> + compatible = "maxim,max2175";
> + reg = <0x60>;
> + clocks = <&maxim_xtal>;
> + clock-names = "xtal";
> + maxim,refout-load-pF = <10>;
> +
> + port {
> + max2175_0_ep: endpoint {
> + remote-endpoint = <&slave_rx_device>;
> + };
> + };
> +
> +};
> diff --git a/Documentation/devicetree/bindings/property-units.txt
> b/Documentation/devicetree/bindings/property-units.txt index
> 12278d7..f1f1c22 100644
> --- a/Documentation/devicetree/bindings/property-units.txt
> +++ b/Documentation/devicetree/bindings/property-units.txt
> @@ -28,6 +28,7 @@ Electricity
> -ohms : Ohms
> -micro-ohms : micro Ohms
> -microvolt : micro volts
> +-pF : pico farads
>
> Temperature
> ----------------------------------------
--
Regards,
Laurent Pinchart
