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tinydrm aims to be a DRM version of drivers/staging/fbtft.
It will live in drivers/gpu/drm/tinydrm and have fbdev support.

No new fbdev drivers are accepted so fbtft is a dead end.

This repo is really just a backup of my development repo, so not much use to anybody else.

Progress: issue #2

How do I test tinydrm?

Only two "known" displays are supported so far: Watterott RPi-Display and Adafruit PiTFT 2.8" since they both have a MI0283QT display panel for which there is a driver.

Apply the latest patchset from issue #2. It will only apply cleanly on linux-next.

Enable the following kernel config options:

CONFIG_DRM
CONFIG_DRM_TINYDRM
CONFIG_TINYDRM_MI0283QT

This is the Device Tree overlay I use with rpi-display on Raspberry Pi:

/*
 * Device Tree overlay for rpi-display by Watterott
 *
 */

/dts-v1/;
/plugin/;

/ {
	compatible = "brcm,bcm2708";

	fragment@0 {
		target = <&spi0>;
		__overlay__ {
			status = "okay";

			spidev@0{
				status = "disabled";
			};

			spidev@1{
				status = "disabled";
			};
		};
	};

	fragment@1 {
		target = <&gpio>;
		__overlay__ {
			rpi_display_pins: rpi_display_pins {
				brcm,pins = <18 23 24 25>;
				brcm,function = <1 1 1 0>; /* out out out in */
			};
		};
	};

	fragment@2 {
		target = <&spi0>;
		__overlay__ {
			/* needed to avoid dtc warning */
			#address-cells = <1>;
			#size-cells = <0>;

			rpidisplay: rpi-display@0{
				compatible = "multi-inno,mi0283qt";
				reg = <0>;
				pinctrl-names = "default";
				pinctrl-0 = <&rpi_display_pins>;

				spi-max-frequency = <32000000>;
				rotation = <0>;
				reset-gpios = <&gpio 23 0>;
				dc-gpios = <&gpio 24 0>;
				backlight = <&backlight>;
			};

			rpi-display-ts@1 {
				compatible = "ti,ads7846";
				reg = <1>;

				spi-max-frequency = <2000000>;
				interrupts = <25 2>; /* high-to-low edge triggered */
				interrupt-parent = <&gpio>;
				pendown-gpio = <&gpio 25 0>;
				ti,x-plate-ohms = /bits/ 16 <60>;
				ti,pressure-max = /bits/ 16 <255>;
			};
		};
	};

	fragment@3 {
		target-path = "/soc";
		__overlay__ {
			backlight: backlight {
				compatible = "gpio-backlight";
				gpios = <&gpio 18 0>;
			};
		};
	};

	__overrides__ {
		speed = <&rpidisplay>,"spi-max-frequency:0";
		rotation = <&rpidisplay>,"rotation:0";
		format = <&rpidisplay>,"format";
	};
};