Here you can find an instruction (openwrt_spi_v3.pdf) and all needed files (Adafruit_Blinka_SPI_Pack.tar) +patch +dts file.
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I got pretty far with ST7789V and the DRM_PANEL_MIPI_DBI driver which provides DRM/KMS interface (and optional fbdev emulation including a text console in case CONFIG_DRM_FBDEV_EMULATION is enabled).
--- a/target/linux/mediatek/files-6.6/arch/arm64/boot/dts/mediatek/mt7988a-bananapi-bpi-r4.dtsi
+++ b/target/linux/mediatek/files-6.6/arch/arm64/boot/dts/mediatek/mt7988a-bananapi-bpi-r4.dtsi
@@ -75,6 +75,15 @@
default-state = "off";
};
};
+
+ backlight: backlight-lcd0 {
+ compatible = "pwm-backlight";
+ pwms = <&pwm 6 50000>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&pwm6_backlight_pins>;
+
+ status = "okay";
+ };
};
ð {
@@ -304,6 +313,18 @@
function = "pwm";
};
};
+
+ pwm6_backlight_pins: pwm6-pins {
+ mux {
+ groups = "pwm6_0";
+ function = "pwm";
+ };
+
+ conf {
+ groups = "pwm6_0";
+ bias-pull-down = <MTK_PUPD_SET_R1R0_10>;
+ };
+ };
};
&pwm {
@@ -402,3 +423,40 @@
&xphy {
status = "okay";
};
+
+&spi1 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ status = "okay";
+
+ display@0 {
+ compatible = "zjy-ips130-v20", "panel-mipi-dbi-spi";
+ reg = <0>;
+ spi-max-frequency = <104000000>;
+ spi-tx-buswidth = <1>;
+ spi-rx-buswidth = <0>;
+ spi-cpha;
+ spi-cpol;
+
+ dc-gpios = <&pio 53 GPIO_ACTIVE_HIGH>;
+ reset-gpios = <&pio 52 GPIO_ACTIVE_HIGH>;
+ backlight = <&backlight>;
+ write-only;
+
+ width-mm = <23>;
+ height-mm = <23>;
+
+ panel-timing {
+ hactive = <240>;
+ vactive = <240>;
+ hback-porch = <0>;
+ vback-porch = <0>;
+ clock-frequency = <0>;
+ hfront-porch = <0>;
+ hsync-len = <0>;
+ vfront-porch = <0>;
+ vsync-len = <0>;
+ };
+ };
+};
(WPEWebKit's cog on wayland/weston)
(sdl2-doom on 240x240 16bpp display, playable with 60fps!)
See https://github.com/notro/panel-mipi-dbi/ for more details.
To make this work on OpenWrt you need to enable the display feature for the filogic target, select kmod-drm-panel-mipi-dbi as well as what ever userland you want to use the display with (eg. cage as Wayland compositor and WPEWebKit's cog as HTML renderer)
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I saw similar article somewhere... 
yes possible that for touch screen part I need to activate something in dts but 
to be honest not sure if it is needed for example in for display st7789 I only mentioned 2 pins but I use more I need to check it out how it works.
About programing it is a bit more complex for me. Im not a real programmer. That;s why I adopted adafruit blinka to use libraries from there to work with my display. If there is no library for SPI device there I think Im not able to enable devices in another way.
Im using python and some modules:
import board
import terminalio
import displayio
Even I think Blinka doesnt work on pure spidev...
Nice, I added SPI LoRa Module sx1262/lr1110 to run Meshtastic
LoRa based mesh
(on OpenWRT One miktroBus also)
and
mixed case from BPi-R4 and OpenWRT One to have sma mount points for GNSS, Wifi scanning, and LoRa
Oh also have a diy usb Meshtick if you have USB but no spare SPI
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Issue with mirrored text solved:
If your text is mirrored please use option polarity 0/1 in function FourWires to correctly display text!
display_bus = FourWire(spi, command=tft_dc, chip_select=tft_cs, polarity=1)
(https://docs.circuitpython.org/en/stable/shared-bindings/fourwire/index.html)
In openwrt_spi_v4.pdf I put info about new version of python/Adafruit:
Adafruit-Blinka version: 8.51.0/Adafruit-platformdetect version: 3.77.0/
Python 3.13
Old instruction is ok in 99% , one change is needed. Of course it is not elegant solution but it is working
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