1. Article purpose[edit source]
This article explains how to configure the LTDC [1] when the peripheral is assigned to the Linux® OS.
The configuration is performed using the device tree mechanism [2].
The Device tree provides a hardware description of the LTDC [1] used by the STM32 LTDC Linux driver.
2. DT bindings documentation[edit source]
The LTDC is represented by the STM32 LTDC device tree bindings [3].
3. DT configuration[edit source]
This hardware description is a combination of the STM32 microprocessor device tree files (.dtsi extension) and board device tree files (.dts extension). See the Device tree for an explanation of the device tree file split.
STM32CubeMX can be used to generate the board device tree. Refer to How to configure the DT using STM32CubeMX for more details.
3.1. DT configuration (STM32 level)[edit source]
The LTDC device tree node is declared in:
- arch/arm/boot/dts/stm32mp135.dtsi on STM32MP13x lines
/ {
soc {
...
ltdc: display-controller@5a001000 {
compatible = "st,stm32-ltdc";
reg = <0x5a001000 0x400>;
interrupts = <GIC_SPI 88 IRQ_TYPE_LEVEL_HIGH>,
<GIC_SPI 89 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&rcc LTDC_PX>;
clock-names = "lcd";
resets = <&scmi_reset RST_SCMI_LTDC>;
status = "disabled";
};
};
};
- arch/arm/boot/dts/stm32mp151.dtsi on STM32MP15x lines
/ {
soc {
...
ltdc: display-controller@5a001000 {
compatible = "st,stm32-ltdc";
reg = <0x5a001000 0x400>;
interrupts = <GIC_SPI 88 IRQ_TYPE_LEVEL_HIGH>,
<GIC_SPI 89 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&rcc LTDC_PX>;
clock-names = "lcd";
resets = <&rcc LTDC_R>;
status = "disabled";
port {
#address-cells = <1>;
#size-cells = <0>;
};
};
};
The declaration (shown above) provides the hardware registers base address, the clocks, the interrupts and the reset. The port may be pre-populated to facilitate its use in the many other device tree files.
3.2. DT configuration (board level)[edit source]
The LTDC device tree related to a particular board may have the following nodes, depending on the board hardware:
- ltdc node: containing the LTDC pinctrl references and the in/out port descriptions
- panel or i2cx bridge rgb node (depending of the board hardware): containing the in/out port descriptions related to the LTDC node
- panel_backlight node (depending of the board hardware): related to the panel or bridge node
A full example of the LTDC pins [4] is available in:
- arch/arm/boot/dts/stm32mp13-pinctrl.dtsi on STM32MP13x lines
&pinctrl {
...
ltdc_pins_a: ltdc-0 {
pins {
pinmux = <STM32_PINMUX('D', 9, AF13)>, /* LCD_CLK */
<STM32_PINMUX('C', 6, AF14)>, /* LCD_HSYNC */
<STM32_PINMUX('G', 4, AF11)>, /* LCD_VSYNC */
<STM32_PINMUX('H', 9, AF11)>, /* LCD_DE */
<STM32_PINMUX('G', 7, AF14)>, /* LCD_R2 */
<STM32_PINMUX('B', 12, AF13)>, /* LCD_R3 */
<STM32_PINMUX('D', 14, AF14)>, /* LCD_R4 */
<STM32_PINMUX('E', 7, AF14)>, /* LCD_R5 */
<STM32_PINMUX('E', 13, AF14)>, /* LCD_R6 */
<STM32_PINMUX('E', 9, AF14)>, /* LCD_R7 */
<STM32_PINMUX('H', 13, AF14)>, /* LCD_G2 */
<STM32_PINMUX('F', 3, AF14)>, /* LCD_G3 */
<STM32_PINMUX('D', 5, AF14)>, /* LCD_G4 */
<STM32_PINMUX('G', 0, AF14)>, /* LCD_G5 */
<STM32_PINMUX('C', 7, AF14)>, /* LCD_G6 */
<STM32_PINMUX('A', 15, AF11)>, /* LCD_G7 */
<STM32_PINMUX('D', 10, AF14)>, /* LCD_B2 */
<STM32_PINMUX('F', 2, AF14)>, /* LCD_B3 */
<STM32_PINMUX('H', 14, AF11)>, /* LCD_B4 */
<STM32_PINMUX('E', 0, AF14)>, /* LCD_B5 */
<STM32_PINMUX('B', 6, AF7)>, /* LCD_B6 */
<STM32_PINMUX('F', 1, AF13)>; /* LCD_B7 */
bias-disable;
drive-push-pull;
slew-rate = <0>;
};
};
ltdc_sleep_pins_a: ltdc-sleep-0 {
pins {
pinmux = <STM32_PINMUX('D', 9, ANALOG)>, /* LCD_CLK */
<STM32_PINMUX('C', 6, ANALOG)>, /* LCD_HSYNC */
<STM32_PINMUX('G', 4, ANALOG)>, /* LCD_VSYNC */
<STM32_PINMUX('H', 9, ANALOG)>, /* LCD_DE */
<STM32_PINMUX('G', 7, ANALOG)>, /* LCD_R2 */
<STM32_PINMUX('B', 12, ANALOG)>, /* LCD_R3 */
<STM32_PINMUX('D', 14, ANALOG)>, /* LCD_R4 */
<STM32_PINMUX('E', 7, ANALOG)>, /* LCD_R5 */
<STM32_PINMUX('E', 13, ANALOG)>, /* LCD_R6 */
<STM32_PINMUX('E', 9, ANALOG)>, /* LCD_R7 */
<STM32_PINMUX('H', 13, ANALOG)>, /* LCD_G2 */
<STM32_PINMUX('F', 3, ANALOG)>, /* LCD_G3 */
<STM32_PINMUX('D', 5, ANALOG)>, /* LCD_G4 */
<STM32_PINMUX('G', 0, ANALOG)>, /* LCD_G5 */
<STM32_PINMUX('C', 7, ANALOG)>, /* LCD_G6 */
<STM32_PINMUX('A', 15, ANALOG)>, /* LCD_G7 */
<STM32_PINMUX('D', 10, ANALOG)>, /* LCD_B2 */
<STM32_PINMUX('F', 2, ANALOG)>, /* LCD_B3 */
<STM32_PINMUX('H', 14, ANALOG)>, /* LCD_B4 */
<STM32_PINMUX('E', 0, ANALOG)>, /* LCD_B5 */
<STM32_PINMUX('B', 6, ANALOG)>, /* LCD_B6 */
<STM32_PINMUX('F', 1, ANALOG)>; /* LCD_B7 */
};
};
...
};
- arch/arm/boot/dts/stm32mp15-pinctrl.dtsi on STM32MP15x lines
&pinctrl {
...
ltdc_pins_a: ltdc-0 {
pins {
pinmux = <STM32_PINMUX('G', 7, AF14)>, /* LCD_CLK */
<STM32_PINMUX('I', 10, AF14)>, /* LCD_HSYNC */
<STM32_PINMUX('I', 9, AF14)>, /* LCD_VSYNC */
<STM32_PINMUX('F', 10, AF14)>, /* LCD_DE */
<STM32_PINMUX('H', 2, AF14)>, /* LCD_R0 */
<STM32_PINMUX('H', 3, AF14)>, /* LCD_R1 */
<STM32_PINMUX('H', 8, AF14)>, /* LCD_R2 */
<STM32_PINMUX('H', 9, AF14)>, /* LCD_R3 */
<STM32_PINMUX('H', 10, AF14)>, /* LCD_R4 */
<STM32_PINMUX('C', 0, AF14)>, /* LCD_R5 */
<STM32_PINMUX('H', 12, AF14)>, /* LCD_R6 */
<STM32_PINMUX('E', 15, AF14)>, /* LCD_R7 */
<STM32_PINMUX('E', 5, AF14)>, /* LCD_G0 */
<STM32_PINMUX('E', 6, AF14)>, /* LCD_G1 */
<STM32_PINMUX('H', 13, AF14)>, /* LCD_G2 */
<STM32_PINMUX('H', 14, AF14)>, /* LCD_G3 */
<STM32_PINMUX('H', 15, AF14)>, /* LCD_G4 */
<STM32_PINMUX('I', 0, AF14)>, /* LCD_G5 */
<STM32_PINMUX('I', 1, AF14)>, /* LCD_G6 */
<STM32_PINMUX('I', 2, AF14)>, /* LCD_G7 */
<STM32_PINMUX('D', 9, AF14)>, /* LCD_B0 */
<STM32_PINMUX('G', 12, AF14)>, /* LCD_B1 */
<STM32_PINMUX('G', 10, AF14)>, /* LCD_B2 */
<STM32_PINMUX('D', 10, AF14)>, /* LCD_B3 */
<STM32_PINMUX('I', 4, AF14)>, /* LCD_B4 */
<STM32_PINMUX('A', 3, AF14)>, /* LCD_B5 */
<STM32_PINMUX('B', 8, AF14)>, /* LCD_B6 */
<STM32_PINMUX('D', 8, AF14)>; /* LCD_B7 */
bias-disable;
drive-push-pull;
slew-rate = <1>;
};
};
ltdc_sleep_pins_a: ltdc-sleep-0 {
pins {
pinmux = <STM32_PINMUX('G', 7, ANALOG)>, /* LCD_CLK */
<STM32_PINMUX('I', 10, ANALOG)>, /* LCD_HSYNC */
<STM32_PINMUX('I', 9, ANALOG)>, /* LCD_VSYNC */
<STM32_PINMUX('F', 10, ANALOG)>, /* LCD_DE */
<STM32_PINMUX('H', 2, ANALOG)>, /* LCD_R0 */
<STM32_PINMUX('H', 3, ANALOG)>, /* LCD_R1 */
<STM32_PINMUX('H', 8, ANALOG)>, /* LCD_R2 */
<STM32_PINMUX('H', 9, ANALOG)>, /* LCD_R3 */
<STM32_PINMUX('H', 10, ANALOG)>, /* LCD_R4 */
<STM32_PINMUX('C', 0, ANALOG)>, /* LCD_R5 */
<STM32_PINMUX('H', 12, ANALOG)>, /* LCD_R6 */
<STM32_PINMUX('E', 15, ANALOG)>, /* LCD_R7 */
<STM32_PINMUX('E', 5, ANALOG)>, /* LCD_G0 */
<STM32_PINMUX('E', 6, ANALOG)>, /* LCD_G1 */
<STM32_PINMUX('H', 13, ANALOG)>, /* LCD_G2 */
<STM32_PINMUX('H', 14, ANALOG)>, /* LCD_G3 */
<STM32_PINMUX('H', 15, ANALOG)>, /* LCD_G4 */
<STM32_PINMUX('I', 0, ANALOG)>, /* LCD_G5 */
<STM32_PINMUX('I', 1, ANALOG)>, /* LCD_G6 */
<STM32_PINMUX('I', 2, ANALOG)>, /* LCD_G7 */
<STM32_PINMUX('D', 9, ANALOG)>, /* LCD_B0 */
<STM32_PINMUX('G', 12, ANALOG)>, /* LCD_B1 */
<STM32_PINMUX('G', 10, ANALOG)>, /* LCD_B2 */
<STM32_PINMUX('D', 10, ANALOG)>, /* LCD_B3 */
<STM32_PINMUX('I', 4, ANALOG)>, /* LCD_B4 */
<STM32_PINMUX('A', 3, ANALOG)>, /* LCD_B5 */
<STM32_PINMUX('B', 8, ANALOG)>, /* LCD_B6 */
<STM32_PINMUX('D', 8, ANALOG)>; /* LCD_B7 */
};
};
ltdc_pins_b: ltdc-1 {
pins {
pinmux = <STM32_PINMUX('I', 14, AF14)>, /* LCD_CLK */
<STM32_PINMUX('I', 12, AF14)>, /* LCD_HSYNC */
<STM32_PINMUX('I', 13, AF14)>, /* LCD_VSYNC */
<STM32_PINMUX('K', 7, AF14)>, /* LCD_DE */
<STM32_PINMUX('I', 15, AF14)>, /* LCD_R0 */
<STM32_PINMUX('J', 0, AF14)>, /* LCD_R1 */
<STM32_PINMUX('J', 1, AF14)>, /* LCD_R2 */
<STM32_PINMUX('J', 2, AF14)>, /* LCD_R3 */
<STM32_PINMUX('J', 3, AF14)>, /* LCD_R4 */
<STM32_PINMUX('J', 4, AF14)>, /* LCD_R5 */
<STM32_PINMUX('J', 5, AF14)>, /* LCD_R6 */
<STM32_PINMUX('J', 6, AF14)>, /* LCD_R7 */
<STM32_PINMUX('J', 7, AF14)>, /* LCD_G0 */
<STM32_PINMUX('J', 8, AF14)>, /* LCD_G1 */
<STM32_PINMUX('J', 9, AF14)>, /* LCD_G2 */
<STM32_PINMUX('J', 10, AF14)>, /* LCD_G3 */
<STM32_PINMUX('J', 11, AF14)>, /* LCD_G4 */
<STM32_PINMUX('K', 0, AF14)>, /* LCD_G5 */
<STM32_PINMUX('K', 1, AF14)>, /* LCD_G6 */
<STM32_PINMUX('K', 2, AF14)>, /* LCD_G7 */
<STM32_PINMUX('J', 12, AF14)>, /* LCD_B0 */
<STM32_PINMUX('J', 13, AF14)>, /* LCD_B1 */
<STM32_PINMUX('J', 14, AF14)>, /* LCD_B2 */
<STM32_PINMUX('J', 15, AF14)>, /* LCD_B3 */
<STM32_PINMUX('K', 3, AF14)>, /* LCD_B4 */
<STM32_PINMUX('K', 4, AF14)>, /* LCD_B5 */
<STM32_PINMUX('K', 5, AF14)>, /* LCD_B6 */
<STM32_PINMUX('K', 6, AF14)>; /* LCD_B7 */
bias-disable;
drive-push-pull;
slew-rate = <1>;
};
};
ltdc_sleep_pins_b: ltdc-sleep-1 {
pins {
pinmux = <STM32_PINMUX('I', 14, ANALOG)>, /* LCD_CLK */
<STM32_PINMUX('I', 12, ANALOG)>, /* LCD_HSYNC */
<STM32_PINMUX('I', 13, ANALOG)>, /* LCD_VSYNC */
<STM32_PINMUX('K', 7, ANALOG)>, /* LCD_DE */
<STM32_PINMUX('I', 15, ANALOG)>, /* LCD_R0 */
<STM32_PINMUX('J', 0, ANALOG)>, /* LCD_R1 */
<STM32_PINMUX('J', 1, ANALOG)>, /* LCD_R2 */
<STM32_PINMUX('J', 2, ANALOG)>, /* LCD_R3 */
<STM32_PINMUX('J', 3, ANALOG)>, /* LCD_R4 */
<STM32_PINMUX('J', 4, ANALOG)>, /* LCD_R5 */
<STM32_PINMUX('J', 5, ANALOG)>, /* LCD_R6 */
<STM32_PINMUX('J', 6, ANALOG)>, /* LCD_R7 */
<STM32_PINMUX('J', 7, ANALOG)>, /* LCD_G0 */
<STM32_PINMUX('J', 8, ANALOG)>, /* LCD_G1 */
<STM32_PINMUX('J', 9, ANALOG)>, /* LCD_G2 */
<STM32_PINMUX('J', 10, ANALOG)>, /* LCD_G3 */
<STM32_PINMUX('J', 11, ANALOG)>, /* LCD_G4 */
<STM32_PINMUX('K', 0, ANALOG)>, /* LCD_G5 */
<STM32_PINMUX('K', 1, ANALOG)>, /* LCD_G6 */
<STM32_PINMUX('K', 2, ANALOG)>, /* LCD_G7 */
<STM32_PINMUX('J', 12, ANALOG)>, /* LCD_B0 */
<STM32_PINMUX('J', 13, ANALOG)>, /* LCD_B1 */
<STM32_PINMUX('J', 14, ANALOG)>, /* LCD_B2 */
<STM32_PINMUX('J', 15, ANALOG)>, /* LCD_B3 */
<STM32_PINMUX('K', 3, ANALOG)>, /* LCD_B4 */
<STM32_PINMUX('K', 4, ANALOG)>, /* LCD_B5 */
<STM32_PINMUX('K', 5, ANALOG)>, /* LCD_B6 */
<STM32_PINMUX('K', 6, ANALOG)>; /* LCD_B7 */
};
};
ltdc_pins_c: ltdc-2 {
pins1 {
pinmux = <STM32_PINMUX('B', 1, AF9)>, /* LTDC_R6 */
<STM32_PINMUX('B', 9, AF14)>, /* LTDC_B7 */
<STM32_PINMUX('C', 0, AF14)>, /* LTDC_R5 */
<STM32_PINMUX('D', 3, AF14)>, /* LTDC_G7 */
<STM32_PINMUX('D', 6, AF14)>, /* LTDC_B2 */
<STM32_PINMUX('D', 10, AF14)>, /* LTDC_B3 */
<STM32_PINMUX('E', 11, AF14)>, /* LTDC_G3 */
<STM32_PINMUX('E', 12, AF14)>, /* LTDC_B4 */
<STM32_PINMUX('E', 13, AF14)>, /* LTDC_DE */
<STM32_PINMUX('E', 15, AF14)>, /* LTDC_R7 */
<STM32_PINMUX('H', 4, AF9)>, /* LTDC_G5 */
<STM32_PINMUX('H', 8, AF14)>, /* LTDC_R2 */
<STM32_PINMUX('H', 9, AF14)>, /* LTDC_R3 */
<STM32_PINMUX('H', 10, AF14)>, /* LTDC_R4 */
<STM32_PINMUX('H', 13, AF14)>, /* LTDC_G2 */
<STM32_PINMUX('H', 15, AF14)>, /* LTDC_G4 */
<STM32_PINMUX('I', 1, AF14)>, /* LTDC_G6 */
<STM32_PINMUX('I', 5, AF14)>, /* LTDC_B5 */
<STM32_PINMUX('I', 6, AF14)>, /* LTDC_B6 */
<STM32_PINMUX('I', 9, AF14)>, /* LTDC_VSYNC */
<STM32_PINMUX('I', 10, AF14)>; /* LTDC_HSYNC */
bias-disable;
drive-push-pull;
slew-rate = <0>;
};
pins2 {
pinmux = <STM32_PINMUX('E', 14, AF14)>; /* LTDC_CLK */
bias-disable;
drive-push-pull;
slew-rate = <1>;
};
};
ltdc_sleep_pins_c: ltdc-sleep-2 {
pins1 {
pinmux = <STM32_PINMUX('B', 1, ANALOG)>, /* LTDC_R6 */
<STM32_PINMUX('B', 9, ANALOG)>, /* LTDC_B7 */
<STM32_PINMUX('C', 0, ANALOG)>, /* LTDC_R5 */
<STM32_PINMUX('D', 3, ANALOG)>, /* LTDC_G7 */
<STM32_PINMUX('D', 6, ANALOG)>, /* LTDC_B2 */
<STM32_PINMUX('D', 10, ANALOG)>, /* LTDC_B3 */
<STM32_PINMUX('E', 11, ANALOG)>, /* LTDC_G3 */
<STM32_PINMUX('E', 12, ANALOG)>, /* LTDC_B4 */
<STM32_PINMUX('E', 13, ANALOG)>, /* LTDC_DE */
<STM32_PINMUX('E', 15, ANALOG)>, /* LTDC_R7 */
<STM32_PINMUX('H', 4, ANALOG)>, /* LTDC_G5 */
<STM32_PINMUX('H', 8, ANALOG)>, /* LTDC_R2 */
<STM32_PINMUX('H', 9, ANALOG)>, /* LTDC_R3 */
<STM32_PINMUX('H', 10, ANALOG)>, /* LTDC_R4 */
<STM32_PINMUX('H', 13, ANALOG)>, /* LTDC_G2 */
<STM32_PINMUX('H', 15, ANALOG)>, /* LTDC_G4 */
<STM32_PINMUX('I', 1, ANALOG)>, /* LTDC_G6 */
<STM32_PINMUX('I', 5, ANALOG)>, /* LTDC_B5 */
<STM32_PINMUX('I', 6, ANALOG)>, /* LTDC_B6 */
<STM32_PINMUX('I', 9, ANALOG)>, /* LTDC_VSYNC */
<STM32_PINMUX('I', 10, ANALOG)>, /* LTDC_HSYNC */
<STM32_PINMUX('E', 14, ANALOG)>; /* LTDC_CLK */
};
};
ltdc_pins_d: ltdc-3 {
pins1 {
pinmux = <STM32_PINMUX('G', 7, AF14)>; /* LCD_CLK */
bias-disable;
drive-push-pull;
slew-rate = <3>;
};
pins2 {
pinmux = <STM32_PINMUX('I', 10, AF14)>, /* LCD_HSYNC */
<STM32_PINMUX('I', 9, AF14)>, /* LCD_VSYNC */
<STM32_PINMUX('E', 13, AF14)>, /* LCD_DE */
<STM32_PINMUX('G', 13, AF14)>, /* LCD_R0 */
<STM32_PINMUX('H', 3, AF14)>, /* LCD_R1 */
<STM32_PINMUX('H', 8, AF14)>, /* LCD_R2 */
<STM32_PINMUX('H', 9, AF14)>, /* LCD_R3 */
<STM32_PINMUX('A', 5, AF14)>, /* LCD_R4 */
<STM32_PINMUX('H', 11, AF14)>, /* LCD_R5 */
<STM32_PINMUX('H', 12, AF14)>, /* LCD_R6 */
<STM32_PINMUX('E', 15, AF14)>, /* LCD_R7 */
<STM32_PINMUX('E', 5, AF14)>, /* LCD_G0 */
<STM32_PINMUX('B', 0, AF14)>, /* LCD_G1 */
<STM32_PINMUX('H', 13, AF14)>, /* LCD_G2 */
<STM32_PINMUX('E', 11, AF14)>, /* LCD_G3 */
<STM32_PINMUX('H', 15, AF14)>, /* LCD_G4 */
<STM32_PINMUX('H', 4, AF9)>, /* LCD_G5 */
<STM32_PINMUX('I', 11, AF9)>, /* LCD_G6 */
<STM32_PINMUX('G', 8, AF14)>, /* LCD_G7 */
<STM32_PINMUX('D', 9, AF14)>, /* LCD_B0 */
<STM32_PINMUX('G', 12, AF14)>, /* LCD_B1 */
<STM32_PINMUX('G', 10, AF14)>, /* LCD_B2 */
<STM32_PINMUX('D', 10, AF14)>, /* LCD_B3 */
<STM32_PINMUX('E', 12, AF14)>, /* LCD_B4 */
<STM32_PINMUX('A', 3, AF14)>, /* LCD_B5 */
<STM32_PINMUX('B', 8, AF14)>, /* LCD_B6 */
<STM32_PINMUX('I', 7, AF14)>; /* LCD_B7 */
bias-disable;
drive-push-pull;
slew-rate = <2>;
};
};
ltdc_sleep_pins_d: ltdc-sleep-3 {
pins {
pinmux = <STM32_PINMUX('G', 7, ANALOG)>, /* LCD_CLK */
<STM32_PINMUX('I', 10, ANALOG)>, /* LCD_HSYNC */
<STM32_PINMUX('I', 9, ANALOG)>, /* LCD_VSYNC */
<STM32_PINMUX('E', 13, ANALOG)>, /* LCD_DE */
<STM32_PINMUX('G', 13, ANALOG)>, /* LCD_R0 */
<STM32_PINMUX('H', 3, ANALOG)>, /* LCD_R1 */
<STM32_PINMUX('H', 8, ANALOG)>, /* LCD_R2 */
<STM32_PINMUX('H', 9, ANALOG)>, /* LCD_R3 */
<STM32_PINMUX('A', 5, ANALOG)>, /* LCD_R4 */
<STM32_PINMUX('H', 11, ANALOG)>, /* LCD_R5 */
<STM32_PINMUX('H', 12, ANALOG)>, /* LCD_R6 */
<STM32_PINMUX('E', 15, ANALOG)>, /* LCD_R7 */
<STM32_PINMUX('E', 5, ANALOG)>, /* LCD_G0 */
<STM32_PINMUX('B', 0, ANALOG)>, /* LCD_G1 */
<STM32_PINMUX('H', 13, ANALOG)>, /* LCD_G2 */
<STM32_PINMUX('E', 11, ANALOG)>, /* LCD_G3 */
<STM32_PINMUX('H', 15, ANALOG)>, /* LCD_G4 */
<STM32_PINMUX('H', 4, ANALOG)>, /* LCD_G5 */
<STM32_PINMUX('I', 11, ANALOG)>, /* LCD_G6 */
<STM32_PINMUX('G', 8, ANALOG)>, /* LCD_G7 */
<STM32_PINMUX('D', 9, ANALOG)>, /* LCD_B0 */
<STM32_PINMUX('G', 12, ANALOG)>, /* LCD_B1 */
<STM32_PINMUX('G', 10, ANALOG)>, /* LCD_B2 */
<STM32_PINMUX('D', 10, ANALOG)>, /* LCD_B3 */
<STM32_PINMUX('E', 12, ANALOG)>, /* LCD_B4 */
<STM32_PINMUX('A', 3, ANALOG)>, /* LCD_B5 */
<STM32_PINMUX('B', 8, ANALOG)>, /* LCD_B6 */
<STM32_PINMUX('I', 7, ANALOG)>; /* LCD_B7 */
};
};
...
};
A full example of the:
- STM32MP13x Discovery board device tree is available arch/arm/boot/dts/stm32mp135f-dk.dts on STM32MP13x lines
/ {
...
panel_rgb: panel-rgb {
compatible = "rocktech,rk043fn48h", "panel-dpi";
enable-gpios = <&gpioi 7 GPIO_ACTIVE_HIGH>;
backlight = <&panel_backlight>;
power-supply = <&scmi_v3v3_sw>;
status = "okay";
width-mm = <105>;
height-mm = <67>;
port {
panel_in_rgb: endpoint {
remote-endpoint = <<dc_out_rgb>;
};
};
panel-timing {
clock-frequency = <10000000>;
hactive = <480>;
vactive = <272>;
hsync-len = <52>;
hfront-porch = <10>;
hback-porch = <10>;
vsync-len = <10>;
vfront-porch = <10>;
vback-porch = <10>;
};
};
...
};
...
<dc {
pinctrl-names = "default", "sleep";
pinctrl-0 = <<dc_pins_a>;
pinctrl-1 = <<dc_sleep_pins_a>;
status = "okay";
port {
#address-cells = <1>;
#size-cells = <0>;
ltdc_out_rgb: endpoint@0 {
reg = <0>;
remote-endpoint = <&panel_in_rgb>;
};
};
};
- STM32MP15x Discovery board device tree is available arch/arm/boot/dts/stm32mp15xx-dkx.dtsi on STM32MP15x lines
...
&i2c1 {
...
hdmi-transmitter@39 {
compatible = "sil,sii9022";
reg = <0x39>;
iovcc-supply = <&v3v3_hdmi>;
cvcc12-supply = <&v1v2_hdmi>;
reset-gpios = <&gpioa 10 GPIO_ACTIVE_LOW>;
interrupts = <1 IRQ_TYPE_EDGE_FALLING>;
interrupt-parent = <&gpiog>;
#sound-dai-cells = <0>;
status = "okay";
ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
sii9022_in: endpoint {
remote-endpoint = <<dc_ep0_out>;
};
};
port@3 {
reg = <3>;
sii9022_tx_endpoint: endpoint {
remote-endpoint = <&i2s2_endpoint>;
};
};
};
};
...
};
<dc {
pinctrl-names = "default", "sleep";
pinctrl-0 = <<dc_pins_a>;
pinctrl-1 = <<dc_sleep_pins_a>;
status = "okay";
port {
ltdc_ep0_out: endpoint@0 {
reg = <0>;
remote-endpoint = <&sii9022_in>;
};
};
};
4. How to configure the DT using STM32CubeMX[edit source]
The STM32CubeMX tool can be used to configure the STM32MPU device and get the corresponding platform configuration device tree files.
The STM32CubeMX may not support all the properties described in the above DT bindings documentation paragraph. If so, the tool inserts user sections in the generated device tree. These sections can then be edited to add some properties and they are preserved from one generation to another. Refer to STM32CubeMX user manual for further information.
5. References[edit source]
Please refer to the following links for additional information: