The Lontium LT8912B MIPI-to-HDMI bridge converts the STM32MP25 MIPI DSI signal to one suitable for HDMI displays.
HDMI is the default configuration for ConnectCore MP25 Development Kit.
Kernel configuration
You can manage the LT8912B support through the following kernel configuration option:
-
Lontium LT8912B MIPI-DSI to LVDS and HDMI/MHL bridge (
CONFIG_DRM_LONTIUM_LT8912
)
This option is enabled as built-in on the default ConnectCore MP25 kernel configuration file.
Kernel driver
The driver for the LT8912B bridge is located at:
File | Description |
---|---|
LT8912B MIPI-to-HDMI bridge driver |
Device tree bindings and customization
The LT8912B bridge is documented at
Documentation/devicetree/bindings/display/bridge/lontium,lt8912.txt
.
The LT8912B bridge is defined in the ConnectCore MP25 Development Kit device tree file.
Definition of the LT8912B
&i2c2 {
...
lt_bridge: lt8912@48 {
compatible = "lontium,lt8912";
reg = <0x48>;
reset-gpios = <&gpiod 4 GPIO_ACTIVE_LOW>;
hpd-gpios = <&gpiod 2 GPIO_ACTIVE_HIGH>;
no-edid;
digi,dsi-lanes = <4>;
status = "okay";
port {
lt8912_1_in: endpoint {
/* add lanes */
remote-endpoint = <&dsi_out>;
};
};
};
};
...
&dsi {
#address-cells = <1>;
#size-cells = <0>;
status = "okay";
ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
dsi_in: endpoint {
remote-endpoint = <<dc_ep0_out>;
};
};
port@1 {
reg = <1>;
dsi_out: endpoint {
remote-endpoint = <<8912_1_in>;
};
};
};
};