On 2017-04-24 18:12, Philipp Zabel wrote:
> This adds device tree binding documentation for mmio-based syscon
> multiplexers controlled by a single bitfield in a syscon register
> range.
Single bitfield?
>
> Signed-off-by: Philipp Zabel <p.za...@pengutronix.de>
> ---
> Changes since v1:
> - Replaced reg, bit-mask, and bit-shift properties with mux-reg-masks array
> to allow defining multiple mux bit-fields per mmio-mux instance.
> - Changed mux-control-cells value to <1>, the cell value is an index into
> the mux-reg-masks array.
> - Replaced idle-state with idle-states array.
> ---
> Documentation/devicetree/bindings/mux/mmio-mux.txt | 60
> ++++++++++++++++++++++
> 1 file changed, 60 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mux/mmio-mux.txt
>
> diff --git a/Documentation/devicetree/bindings/mux/mmio-mux.txt
> b/Documentation/devicetree/bindings/mux/mmio-mux.txt
> new file mode 100644
> index 0000000000000..99282fa761c55
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mux/mmio-mux.txt
> @@ -0,0 +1,60 @@
> +MMIO register bitfield-based multiplexer controller bindings
> +
> +Define register bitfields to be used to control multiplexers. The parent
> +device tree node must be a syscon node to provide register access.
> +
> +Required properties:
> +- compatible : "mmio-mux"
> +- #mux-control-cells : <1>
> +- mux-reg-masks : an array of register offset and pre-shifted bitfield mask
> + pairs, each describing a single mux control.
> +* Standard mux-controller bindings as decribed in mux-controller.txt
> +
> +Optional properties:
> +- idle-states : if present, the state the muxes will have when idle. The
> + special state MUX_IDLE_AS_IS is the default.
> +
> +The multiplexer state is defined as the value of the bitfield described
> +by the reg, bit-mask, and bit-shift properties, accessed through the parent
> +syscon.
This paragraph needs updating.
> +
> +Example:
> +
> + syscon {
> + compatible = "syscon";
> +
> + mux: mux-controller@3 {
You shouldn't do ...@3 if you don't have a reg property.
Cheers,
peda
> + compatible = "mmio-mux";
> + #mux-control-cells = <1>;
> +
> + mux-reg-masks = <0x3 0x30>, /* 0: reg 0x3, bits 5:4 */
> + <0x3 0x40>, /* 1: reg 0x3, bit 6 */
> + idle-states = <MUX_IDLE_AS_IS>, <0>;
> + };
> + };
> +
> + video-mux {
> + compatible = "video-mux";
> + mux-controls = <&mux 0>;
> +
> + ports {
> + /* inputs 0..3 */
> + port@0 {
> + reg = <0>;
> + };
> + port@1 {
> + reg = <1>;
> + };
> + port@2 {
> + reg = <2>;
> + };
> + port@3 {
> + reg = <3>;
> + };
> +
> + /* output */
> + port@4 {
> + reg = <4>;
> + };
> + };
> + };
>
