Tool/software:
Hello,
I’m working with the SN65DSI84 bridge chip to drive an AUO P370IVN02.2 panel using a Raspberry Pi Compute Module 4S.
The strange thing is:
In test pattern mode, everything looks fine. The LVDS clock and data lines are active, and the panel shows the internal pattern.
But with real video input (DSI), only the LVDS clock comes out. The data lines stay inactive, even though I can see that DSI clock and data are present on the input side.
PLL lock is OK. I’ll attach my i2cdump and DTS settings so you can see exactly what I’m using.
/dts-v1/;
/plugin/;
#include <dt-bindings/gpio/gpio.h>
#include <dt-bindings/pinctrl/bcm2835.h>
/ {
compatible = "brcm,bcm2835";
/* PWM0 function */
fragment@0 {
target = <&gpio>;
__overlay__ {
pwm_pins: pwm_pins {
brcm,pins = <18>;
brcm,function = <BCM2835_FSEL_ALT5>; // PWM1_0
brcm,pull = <0>;
};
};
};
fragment@1 {
target = <&pwm>;
__overlay__ {
pinctrl-names = "default";
pinctrl-0 = <&pwm_pins>;
assigned-clock-rates = <50000000>;
status = "okay";
};
};
fragment@2 {
target-path = "/";
__overlay__ {
backlight_lvds: backlight {
compatible = "pwm-backlight";
pwms = <&pwm 0 1000000 0>; // 1KHz
brightness-levels = <0 1000>;
num-interpolated-steps = <1000>;
default-brightness-level = <400>;
enable-gpios = <&gpio 39 GPIO_ACTIVE_HIGH>;
};
panel: panel {
compatible = "panel-lvds";
backlight = <&backlight_lvds>;
label = "AUO:G156HAN";
dual-link;
width-mm = <904>;
height-mm = <254>;
data-mapping = "vesa-24";
panel-timing {
clock-frequency = <45000000>;
hactive = <1920>;
hsync-len = <162>;
hfront-porch = <80>;
hback-porch = <80>;
vactive = <540>;
vsync-len = <15>;
vfront-porch = <15>;
vback-porch = <15>;
};
ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
dual-lvds-odd-pixels;
panel_in_a: endpoint {
remote-endpoint = <&bridge_out_a>;
};
};
port@1 {
reg = <1>;
dual-lvds-even-pixels;
panel_in_b: endpoint {
remote-endpoint = <&bridge_out_b>;
};
};
};
};
};
};
fragment@3 {
target = <&i2c0if>;
__overlay__ {
#address-cells = <1>;
#size-cells = <0>;
status = "okay";
bridge@2c {
compatible = "ti,sn65dsi84";
reg = <0x2c>;
vcc-supply = <&vcc_1v8>;
enable-gpios = <&gpio 42 GPIO_ACTIVE_HIGH>;
ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
bridge_in: endpoint {
remote-endpoint = <&dsi_out>;
data-lanes = <1 2 3 4>;
};
};
port@2 {
reg = <2>;
bridge_out_a: endpoint {
remote-endpoint = <&panel_in_a>;
};
};
port@3 {
reg = <3>;
bridge_out_b: endpoint {
remote-endpoint = <&panel_in_b>;
};
};
};
};
};
};
fragment@4 {
target = <&dsi1>;
__overlay__ {
#address-cells = <1>;
#size-cells = <0>;
status = "okay";
port {
dsi_out: endpoint {
remote-endpoint = <&bridge_in>;
};
};
};
};
fragment@5 {
target = <&i2c0if>;
__overlay__ {
status = "okay";
};
};
fragment@6 {
target = <&i2c0mux>;
__overlay__ {
status = "disabled";
};
};
fragment@7 {
target-path = "/";
__overlay__ {
vcc_1v8: vcc_1v8 {
compatible = "regulator-fixed";
regulator-name = "vcc_1v8";
regulator-min-microvolt = <1800000>;
regulator-max-microvolt = <1800000>;
regulator-always-on;
};
};
};
};
No size specified (using byte-data access)
0 1 2 3 4 5 6 7 8 9 a b c d e f 0123456789abcdef
00: 35 38 49 53 44 20 20 20 01 00 83 28 00 01 00 00 58ISD ?.?(.?..
10: 26 00 32 00 00 00 00 00 4c 05 03 00 00 00 00 00 &.2.....L??.....
20: 80 07 00 00 1c 02 00 00 21 00 00 00 2c 00 00 00 ??..??..!...,...
30: 05 00 00 00 94 00 0f 00 50 00 02 00 00 00 00 00 ?...?.?.P.?.....
40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
f0: 00 00 00 00 40 00 00 80 00 00 00 00 00 00 00 00 ....@..?........
Any advice would be really helpful. Thanks a lot!
