From: Hans Verkuil Date: Wed, 2 Aug 2017 07:22:33 +0000 (-0400) Subject: media: dt-bindings: document the CEC GPIO bindings X-Git-Tag: v4.15~397^2~329 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=67f2a06f14a9419bc2da0a8e6b440c6813dccdb0;p=mirror_ubuntu-bionic-kernel.git media: dt-bindings: document the CEC GPIO bindings Document the bindings for the cec-gpio module for hardware where the CEC line and optionally the HPD line are connected to GPIO lines. Signed-off-by: Hans Verkuil Reviewed-by: Linus Walleij Reviewed-by: Rob Herring Signed-off-by: Mauro Carvalho Chehab --- diff --git a/Documentation/devicetree/bindings/media/cec-gpio.txt b/Documentation/devicetree/bindings/media/cec-gpio.txt new file mode 100644 index 000000000000..46a0bac8b3b9 --- /dev/null +++ b/Documentation/devicetree/bindings/media/cec-gpio.txt @@ -0,0 +1,32 @@ +* HDMI CEC GPIO driver + +The HDMI CEC GPIO module supports CEC implementations where the CEC line +is hooked up to a pull-up GPIO line and - optionally - the HPD line is +hooked up to another GPIO line. + +Required properties: + - compatible: value must be "cec-gpio". + - cec-gpios: gpio that the CEC line is connected to. The line should be + tagged as open drain. + +If the CEC line is associated with an HDMI receiver/transmitter, then the +following property is also required: + + - hdmi-phandle - phandle to the HDMI controller, see also cec.txt. + +If the CEC line is not associated with an HDMI receiver/transmitter, then +the following property is optional: + + - hpd-gpios: gpio that the HPD line is connected to. + +Example for the Raspberry Pi 3 where the CEC line is connected to +pin 26 aka BCM7 aka CE1 on the GPIO pin header and the HPD line is +connected to pin 11 aka BCM17: + +#include + +cec-gpio { + compatible = "cec-gpio"; + cec-gpios = <&gpio 7 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>; + hpd-gpios = <&gpio 17 GPIO_ACTIVE_HIGH>; +};