On Sun, 12 Aug 2018 20:46:24 +0200
Sam Ravnborg <sam@xxxxxxxxxxxx> wrote:
> The LCDC IP used by some Atmel SOC's have a
> multifunction device that include two sub-devices:
> - pwm
> - display controller
>
> This binding describe the multi function device
> that act as root for the sub-devices
>
> The Atmel SOC's are at91sam9 etc.
>
> The compatible name is intentionally
> prefixed with -mfd to avoid clash with existing
> compatible entries.
>
> Signed-off-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
> Cc: Lee Jones <lee.jones@xxxxxxxxxx>
> Cc: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
> ---
> .../devicetree/bindings/mfd/atmel-lcdc.txt | 75 ++++++++++++++++++++++
> 1 file changed, 75 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mfd/atmel-lcdc.txt
>
> diff --git a/Documentation/devicetree/bindings/mfd/atmel-lcdc.txt b/Documentation/devicetree/bindings/mfd/atmel-lcdc.txt
> new file mode 100644
> index 000000000000..70e9b7bda6c7
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/atmel-lcdc.txt
> @@ -0,0 +1,75 @@
> +Device-Tree bindings for Atmel's LCDC (LCD Controller) MFD driver
> +
> +Required properties:
> + - compatible: value should be one of the following:
> + "atmel,at91sam9261-lcdc-mfd"
> + "atmel,at91sam9263-lcdc-mfd"
> + "atmel,at91sam9g10-lcdc-mfd"
> + "atmel,at91sam9g45-lcdc-mfd"
> + "atmel,at91sam9g46-lcdc-mfd"
> + "atmel,at91sam9m10-lcdc-mfd"
> + "atmel,at91sam9m11-lcdc-mfd"
> + "atmel,at91sam9rl-lcdc-mfd"
I'm pretty sure we don't want the -mfd suffix in the compatible. I know
it's here to avoid clashes with the old binding, so maybe we can find
name.
> + - reg: base address and size of the LCDC device registers.
> + - clock-names: the name of the 2 clocks requested by the LCDC device.
> + Should contain "lcdc_clk", and "hclk".
> + - clocks: should contain the 2 clocks requested by the LCDC device.
> + May specify the same clock twice is there is no need to enable
> + "hclk" to use the display.
> + - interrupts: should contain the description of the LCDC interrupt line
> +
> +The LCDC IP exposes two subdevices:
> + - a PWM chip: see ../pwm/atmel-lcdc-pwm.txt
> + - a Display Controller: see ../display/atmel/lcdc-display-controller.txt
> +
> +Example:
> + lcdc0: lcdc@700000 {
> + compatible = "atmel,at91sam9263-lcdc-mfd";
> + reg = <0x700000 0x1000>;
> + interrupts = <26 IRQ_TYPE_LEVEL_HIGH 3>;
> + clocks = <&lcd_clk>, <&lcd_clk>;
> + clock-names = "lcdc_clk", "hclk";
> +
> + lcdc-display-controller {
> + compatible = "atmel,lcdc-display-controller";
> + lcd-supply = <&lcdc_reg>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + port@0 {
> + reg = <0>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + lcdc_panel_output: endpoint@0 {
> + reg = <0>;
> + remote-endpoint = <&panel_input>;
> + };
> + };
> + };
> +
> + lcdc_pwm: lcdc-pwm {
> + compatible = "atmel,lcdc-pwm";
> + pinctrl-names = "default";
> + pinctrl-0 = <&pinctrl_lcdc_pwm>;
> + #pwm-cells = <3>;
> + };
> +
> + };
Also, I don't remember why I decided to declare distinct nodes for the
PWM and display controller, but you should probably try to only declare
the lcdc node. Something like that:
lcdc0: lcdc@700000 {
compatible = "atmel,at91sam9263-lcdc";
reg = <0x700000 0x1000>;
interrupts = <26 IRQ_TYPE_LEVEL_HIGH 3>;
clocks = <&lcd_clk>, <&lcd_clk>;
clock-names = "lcdc_clk", "hclk";
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_lcdc_pwm ...>;
#pwm-cells = <3>;
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
#address-cells = <1>;
#size-cells = <0>;
lcdc_panel_output: endpoint@0 {
reg = <0>;
remote-endpoint = <&panel_input>;
};
};
};
Note that this representation does not prevent us from having an MFD
which declares the PWM and Display Engine, it's just that all devs will
point to the same of_node.
> +
> + lcdc-display-controller {
> + compatible = "atmel,lcdc-display-controller";
> + lcd-supply = <&lcdc_reg>;
Hm, is this a regulator for the LCD controller or the LCD? If it's for
the LCD it should be placed under the panel node.
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + port@0 {
> + reg = <0>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + lcdc_panel_output: endpoint@0 {
> + reg = <0>;
> + remote-endpoint = <&panel_input>;
> + };
> + };
> + };
> +
> + lcdc_pwm: lcdc-pwm {
> + compatible = "atmel,lcdc-pwm";
> + pinctrl-names = "default";
> + pinctrl-0 = <&pinctrl_lcdc_pwm>;
> + #pwm-cells = <3>;
> + };
> +
> + };
> +
> + panel: panel {
> + compatible = "logictechnologies,lttd800480070-l2rt", "simple-panel";
> + backlight = <&backlight>;
> + power-supply = <&panel_reg>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + port@0 {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + panel_input: endpoint@0 {
> + reg = <0>;
> + remote-endpoint = <&lcdc_panel_output>;
> + };
> + };
> + };
