Hi,
I am trying to connect a LVDS display to our custom base board.
With BSP 6.8.0 I get it working with the following device-tree-overlay (derived from verdin-am62_mezzanine_panel-cap-touch-10inch-lvds_overlay.dts)
// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
/*
* Copyright 2023 Toradex
*/
// Verdin AM62 Mezzanine single-channel LVDS
/dts-v1/;
/plugin/;
#include <dt-bindings/gpio/gpio.h>
#include <dt-bindings/interrupt-controller/irq.h>
#include <dt-bindings/pwm/pwm.h>
#include "verdin-am62_dtv_mezzanine_backlight.dtsi"
/ {
compatible = "toradex,verdin-am62";
};
&{/} {
panel-lvds-mez {
compatible = "panel-lvds";
backlight = <&backlight_mezzanine>;
data-mapping = "jeida-24"; /* "vesa-24"; */
height-mm = <66>; /* 136 */
width-mm = <109>; /* 217 */
panel-timing {
clock-frequency = <23000000 25000000 27000000>; /* 68900000 71100000 73400000 */
de-active = <1>; /* 1 */
hactive = <800 800 800 >; /* 1280 1280 1280 */
hback-porch = <4 8 48>; /* 23 60 71 */
hfront-porch = <4 8 48>; /* 23 60 71 */
hsync-active = <0>; /* 0 */
hsync-len = <2 4 8>; /* 15 40 47 */
pixelclk-active = <1>; /* positive edge */ /* 1 */
vactive = <480 480 480>; /* 800 800 800 */
vback-porch = <4 8 12>; /* 5 7 10 */
vfront-porch = <4 8 12>; /* 5 7 10 */
vsync-active = <0>; /* 0 */
vsync-len = <2 4 8>; /* 6 9 12 */
};
port {
panel_lvds_in: endpoint {
remote-endpoint = <&oldi_out0>;
};
};
};
};
&dss {
status = "okay";
};
/*
* If the bridge is missing setting up dss will fail. As this bridge
* isn't available on all SKU disable it here.
* Thus having an overlay for the DSI output enabled concurrently
* with this one will not work.
*/
&dsi_bridge {
status = "disabled";
};
&dss_ports {
#address-cells = <1>;
#size-cells = <0>;
/* VP1: LVDS Output (OLDI TX 0) */
port@0 {
reg = <0>;
oldi_out0: endpoint {
remote-endpoint = <&panel_lvds_in>;
};
};
};
/* Verdin I2C_2_DSI */
&main_i2c2 {
#address-cells = <1>;
#size-cells = <0>;
clock-frequency = <400000>;
status = "okay";
hycon_hy46xx: touchscreen@38 { /* 4a */
compatible = "hycon,hy4635"; /* atmel,maxtouch */
reg = <0x38>; /* 4a */
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_dsi1_int>, <&pinctrl_i2s_2_bclk_gpio>;
/*
* Already muxed as GPIOs in k3-am625-verdin-dev.dtsi
*
* interrupt-parent = <&main_gpio1>;
* interrupts = <49 IRQ_TYPE_EDGE_FALLING>;
* pinctrl-names = "default";
* pinctrl-0 = <&pinctrl_dsi1_int>, <&pinctrl_i2s_2_bclk_gpio>;
*
* reset-gpios = <&main_gpio0 35 GPIO_ACTIVE_LOW>; // Verdin I2S_2_BCLK (TOUCH_RESET#, SODIMM 42)
* pinctrl-names = "default";
* pinctrl-0 = <&pinctrl_gpio_2 &pinctrl_gpio_3>;
*/
/* Verdin GPIO_2 (SODIMM 208) */
/* Verdin GPIO_3 (SODIMM 210) */
interrupt-parent = <&main_gpio1>;
interrupts = <49 IRQ_TYPE_EDGE_FALLING>;
reset-gpios = <&main_gpio0 35 GPIO_ACTIVE_LOW>;
status= "okay";
/*
* interrupt-parent = <&mcu_gpio0>;
* interrupts = <3 IRQ_TYPE_EDGE_FALLING>;
* reset-gpios = <&mcu_gpio0 2 GPIO_ACTIVE_LOW>;
* status= "okay";
*/
};
};
&hycon_hy46xx{
status = "okay";
};
verdin-am62_dtv_mezzanine_backlight.dtsi (690 Bytes)
verdin-am62_dtv_lvds_direct_overlay.dts (2.9 KB)
However when switching to BSP 7.1.0 the display doesn’t work with this overlay (again derived from verdin-am62_mezzanine_panel-cap-touch-10inch-lvds_overlay.dts (toradex_ti-linux-6.6.y))
// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
/*
* Copyright 2023 Toradex
*/
// Verdin AM62 Mezzanine single-channel LVDS
/dts-v1/;
/plugin/;
#include <dt-bindings/gpio/gpio.h>
#include <dt-bindings/interrupt-controller/irq.h>
#include <dt-bindings/pwm/pwm.h>
#include "verdin-am62_dtv_mezzanine_backlight.dtsi"
/ {
compatible = "toradex,verdin-am62";
};
&{/} {
panel-lvds-mez {
compatible = "panel-lvds";
#address-cells = <1>;
#size-cells = <0>;
backlight = <&backlight_mezzanine>;
data-mapping = "jeida-24"; /* "vesa-24"; */
height-mm = <66>; /* 136 */
width-mm = <109>; /* 217 */
panel-timing {
clock-frequency = <23000000 25000000 27000000>; /* 68900000 71100000 73400000 */
de-active = <1>; /* 1 */
hactive = <800 800 800 >; /* 1280 1280 1280 */
hback-porch = <4 8 48>; /* 23 60 71 */
hfront-porch = <4 8 48>; /* 23 60 71 */
hsync-active = <0>; /* 0 */
hsync-len = <2 4 8>; /* 15 40 47 */
pixelclk-active = <1>; /* positive edge */ /* 1 */
vactive = <480 480 480>; /* 800 800 800 */
vback-porch = <4 8 12>; /* 5 7 10 */
vfront-porch = <4 8 12>; /* 5 7 10 */
vsync-active = <0>; /* 0 */
vsync-len = <2 4 8>; /* 6 9 12 */
};
port@0 {
reg = <0>;
panel_lvds_in: endpoint {
remote-endpoint = <&oldi_0_out>;
};
};
/* HACK to make oldi1 happy */
port@1 {
reg = <1>;
panel_lvds_in1: endpoint {
remote-endpoint = <&oldi_1_out>;
};
};
};
};
&dss {
status = "okay";
};
/*
* If the bridge is missing setting up dss will fail. As this bridge
* isn't available on all SKU disable it here.
* Thus having an overlay for the DSI output enabled concurrently
* with this one will not work.
* &dsi_bridge {
* status = "disabled";
*};
*/
&dss_ports {
#address-cells = <1>;
#size-cells = <0>;
/* VP1: Output to OLDI */
port@0 {
reg = <0>;
#address-cells = <1>;
#size-cells = <0>;
dpi0_out0: endpoint@0 {
reg = <0>;
remote-endpoint = <&oldi_0_in>;
};
dpi0_out1: endpoint@1 {
reg = <1>;
remote-endpoint = <&oldi_1_in>;
};
};
};
/* Verdin I2C_2_DSI */
&main_i2c2 {
#address-cells = <1>;
#size-cells = <0>;
clock-frequency = <400000>;
status = "okay";
hycon_hy46xx: touchscreen@38 { /* 4a */
compatible = "hycon,hy4635"; /* atmel,maxtouch */
reg = <0x38>; /* 4a */
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_dsi1_int>, <&pinctrl_i2s_2_bclk_gpio>;
/*
* Already muxed as GPIOs in k3-am625-verdin-dev.dtsi
*
* interrupt-parent = <&main_gpio1>;
* interrupts = <49 IRQ_TYPE_EDGE_FALLING>;
* pinctrl-names = "default";
* pinctrl-0 = <&pinctrl_dsi1_int>, <&pinctrl_i2s_2_bclk_gpio>;
*
* reset-gpios = <&main_gpio0 35 GPIO_ACTIVE_LOW>; // Verdin I2S_2_BCLK (TOUCH_RESET#, SODIMM 42)
* pinctrl-names = "default";
* pinctrl-0 = <&pinctrl_gpio_2 &pinctrl_gpio_3>;
*/
/* Verdin GPIO_2 (SODIMM 208) */
/* Verdin GPIO_3 (SODIMM 210) */
interrupt-parent = <&main_gpio1>;
interrupts = <49 IRQ_TYPE_EDGE_FALLING>;
reset-gpios = <&main_gpio0 35 GPIO_ACTIVE_LOW>;
status= "okay";
/*
* interrupt-parent = <&mcu_gpio0>;
* interrupts = <3 IRQ_TYPE_EDGE_FALLING>;
* reset-gpios = <&mcu_gpio0 2 GPIO_ACTIVE_LOW>;
* status= "okay";
*/
};
};
&hycon_hy46xx{
status = "okay";
};
&oldi0 {
status = "okay";
};
&oldi0_ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
oldi_0_in: endpoint {
remote-endpoint = <&dpi0_out0>;
};
};
port@1 {
reg = <1>;
oldi_0_out: endpoint {
remote-endpoint = <&panel_lvds_in>;
};
};
};
/*
* HACK: With oldi1 disable oldi always returns EAGAIN making the panel not
* show anything, so pretend we are in clone mode.
*/
&oldi1 {
status = "okay";
};
&oldi1_ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
oldi_1_in: endpoint {
remote-endpoint = <&dpi0_out1>;
};
};
port@1 {
reg = <1>;
oldi_1_out: endpoint {
remote-endpoint = <&panel_lvds_in1>;
};
};
};
verdin-am62_dtv_lvds_overlay_oldi.dts (3.9 KB)
The working configuration:
verdin-am62_dtv_lvds_direct_overlay.dts
verdin-am62_dtv_mezzanine_backlight.dtsi
Software summary
------------------------------------------------------------
Bootloader: U-Boot
Kernel version: 6.1.83-6.8.0+git.8e6ca06a787a #1 SMP PREEMPT Fri Sep 27 07:54:42 UTC 2024
Kernel command line: root=PARTUUID=f3eca8c6-02 ro rootwait console=null console=ttyS2,115200 consoleblank=0 vt.global_cursor_default=0 earlycon=ns16550a,mmio32,0x02800000
Distro name: NAME="TDX Wayland with XWayland"
Distro version: VERSION_ID=6.8.0-build.14
Distro variant: -
Hostname: verdin-am62-15190221
------------------------------------------------------------
Hardware info
------------------------------------------------------------
HW model: Toradex Verdin AM62 on Verdin Development Board
Toradex version: 0074 V1.1A
Serial number: 15190221
Processor arch: aarch64
------------------------------------------------------------
The configuration which does not work:
verdin-am62_dtv_lvds_overlay_oldi.dts
verdin-am62_dtv_mezzanine_backlight.dtsi
Software summary
------------------------------------------------------------
Bootloader: U-Boot
Kernel version: 6.6.58-7.1.0-gf874412b7190 #1 SMP PREEMPT Fri Dec 6 14:07:48 UTC 2024
Kernel command line: root=PARTUUID=760dc376-02 ro rootwait console=tty1 console=ttyS2,115200
Distro name: NAME="TDX Wayland with XWayland"
Distro version: VERSION_ID=7.1.0-build.3
Distro variant: -
Hostname: verdin-am62-15190213
------------------------------------------------------------
Hardware info
------------------------------------------------------------
HW model: Toradex Verdin AM62 on Verdin Development Board
Toradex version: 0074 V1.1A
Serial number: 15190213
Processor arch: aarch64
------------------------------------------------------------
