[Freedreno] [PATCH v5 2/4] dt-bindings: drm/bridge: Document sn65dsi86 bridge bindings

[Stephen Boyd]

Quoting Sandeep Panda (2018-05-01 21:32:00)
> diff --git a/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt b/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt
> new file mode 100644
> index 0000000..0d042ce
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.txt
> @@ -0,0 +1,76 @@
> +SN65DSI86 DSI to eDP bridge chip
> +--------------------------------
> +
> +This is the binding for Texas Instruments SN65DSI86 bridge.
> +http://www.ti.com/general/docs/lit/getliterature.tsp?genericPartNumber=sn65dsi86&fileType=pdf
> +
> +Required properties:
> +- compatible: Must be "ti,sn65dsi86"
> +- reg: i2c address of the chip, 0x2d as per datasheet
> +- enable-gpios: OF device-tree gpio specification for bridge_en pin
> +
> +- vccio-supply: A 1.8V supply that powers up the digital IOs.
> +- vpll-supply: A 1.8V supply that powers up the displayport PLL.
> +- vcca-supply: A 1.2V supply that powers up the analog circuits.
> +- vcc-supply: A 1.2V supply that powers up the digital core.
> +
> +Optional properties:
> +- interrupts: Specifier for the SN65DSI86 interrupt line.
> +- hpd-gpios: OF device-tree gpio specifications for HPD pin.
> +
> +- refclk-freq-khz: Value specifying the frequency of reference clock in KHz unit.

Please use the clocks property instead. We may need to turn the clk on
first before this can work so the driver would use the clk framework (at
least in linux). clock-names could have 'refclk' because that's the pin
name.

Is there a way in DRM to figure out the frequency of the clock frequency
for DACP/N? It looks like if refclk is grounded, then the DACP/N pins
from the DSI side should be one of a set of frequencies, so I'm just
curious how that will work and if the binding would need to be updated
to indicate what the frequency of the DSI clock lane is, or if DRM can
tell this driver through the port/graph stuff somehow.

> +
> +- gpio-controller: Marks the device has a GPIO controller.
> +- #gpio-cells: Number of GPIO cells. Refer to binding document "gpio/gpio.txt"

What's the number? 2?

> +- #pwm-cells : Number of cells used to specify a PWM. See pwm.txt in this directory
> +              for a description of the cell formats.

What's the number? 1? There's a pwm.txt in this directory?