precompiled stuff

device-tree/sun20i-d1-mangopi-mq-pro.generic.dts

@@ -5,6 +5,7 @@
 
 #include <dt-bindings/gpio/gpio.h>
 #include <dt-bindings/leds/common.h>
+#include <dt-bindings/pwm/pwm.h>
 
 #include "sun20i-d1.dtsi"
 #include "sun20i-d1-common-regulators.dtsi"
@@ -16,7 +17,6 @@
 	aliases {
 		ethernet0 = &rtl8723ds;
 		mmc0 = &mmc0;
-		serial0 = &uart0;
 	};
 
 	chosen {
@@ -34,14 +34,14 @@
 		};
 	};
 
-	leds {
-		compatible = "pwm-leds";
 
-		led {
+	leds {
+		compatible = "gpio-leds";
+
+		led-0 {
 			color = <LED_COLOR_ID_BLUE>;
 			function = LED_FUNCTION_STATUS;
-			max-brightness = <255>;
-			pwms = <&pwm 2 50000 0>;
+			gpios = <&pio 3 18 GPIO_ACTIVE_HIGH>; /* PD18 */
 		};
 	};
 
@@ -138,6 +138,36 @@
 	vcc-pe-supply = <&reg_avdd2v8>;
 };
 
+&spi1 {
+	pinctrl-0 = <&spi1_pd_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&i2c0 {
+	pinctrl-0 = <&i2c0_pg12_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+/*&i2c1 {
+	pinctrl-0 = <&i2c1_pb4_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};*/
+
+/*&i2c2 {
+	pinctrl-0 = <&i2c2_pc0_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};*/
+
+&i2c3 {
+	pinctrl-0 = <&i2c3_pe16_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
 &uart0 {
 	pinctrl-0 = <&uart0_pb8_pins>;
 	pinctrl-names = "default";
@@ -158,6 +188,38 @@
 	};
 };
 
+&uart2 {
+	pinctrl-0 = <&uart2_pc0_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+/*&uart3 {
+	uart-has-rtscts;
+	pinctrl-0 = <&uart3_pd10_pins>, <&uart3_pd13_rts_cts_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};*/
+
+&uart4 {
+	pinctrl-0 = <&uart4_pb2_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+/*&uart5 {
+	pinctrl-0 = <&uart5_pb4_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};*/
+
+&pwm {
+	//pinctrl-0 = <&pwm0_pb12_pin>, <&pwm2_pd18_pin>;
+	pinctrl-0 = <&pwm0_pb12_pin>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
 &usb_otg {
 	dr_mode = "peripheral";
 	status = "okay";

device-tree/sun20i-d1.dtsi

@@ -132,17 +132,29 @@
 			};
 
 			/omit-if-no-ref/
-			i2c0_pb10_pins: i2c0-pb10-pins {
-				pins = "PB10", "PB11";
+			i2c0_pg12_pins: i2c0-pg12-pins {
+				pins = "PG12", "PG13";
 				function = "i2c0";
 			};
 
 			/omit-if-no-ref/
-			i2c2_pb0_pins: i2c2-pb0-pins {
-				pins = "PB0", "PB1";
+			i2c1_pb4_pins: i2c1-pb4-pins {
+				pins = "PB4", "PB5";
+				function = "i2c1";
+			};
+
+			/omit-if-no-ref/
+			i2c2_pc0_pins: i2c2-pc0-pins {
+				pins = "PC0", "PC1";
 				function = "i2c2";
 			};
 
+			/omit-if-no-ref/
+			i2c3_pe16_pins: i2c3-pe16-pins {
+				pins = "PE16", "PE17";
+				function = "i2c3";
+			};
+
 			/omit-if-no-ref/
 			lcd_rgb666_pins: lcd-rgb666-pins {
 				pins = "PD0", "PD1", "PD2", "PD3", "PD4", "PD5",
@@ -191,6 +203,18 @@
 				function = "emac";
 			};
 
+			/omit-if-no-ref/
+			pwm0_pb5_pin: pwm0-pb5-pin {
+				pins = "PB5";
+				function = "pwm0";
+			};
+
+			/omit-if-no-ref/
+			pwm0_pb12_pin: pwm0-pb12-pin {
+				pins = "PB12";
+				function = "pwm0";
+			};
+
 			/omit-if-no-ref/
 			pwm0_pd16_pin: pwm0-pd16-pin {
 				pins = "PD16";
@@ -250,6 +274,42 @@
 				pins = "PG8", "PG9";
 				function = "uart1";
 			};
+
+			/omit-if-no-ref/
+			uart2_pb0_pins: uart2-pb0-pins {
+				pins = "PB0", "PB1";
+				function = "uart2";
+			};
+
+			/omit-if-no-ref/
+			uart2_pc0_pins: uart2-pc0-pins {
+				pins = "PC0", "PC1";
+				function = "uart2";
+			};
+
+			/omit-if-no-ref/
+			uart3_pd10_pins: uart3-pd10-pins {
+				pins = "PD10", "PD11";
+				function = "uart3";
+			};
+
+			/omit-if-no-ref/
+			uart3_pd13_rts_cts_pins: uart3-pd13-rts-cts-pins {
+				pins = "PD13", "PD14";
+				function = "uart3";
+			};
+
+			/omit-if-no-ref/
+			uart4_pb2_pins: uart4-pb2-pins {
+				pins = "PB2", "PB3";
+				function = "uart4";
+			};
+
+			/omit-if-no-ref/
+			uart5_pb4_pins: uart5-pb4-pins {
+				pins = "PB4", "PB5";
+				function = "uart5";
+			};
 		};
 
 		pwm: pwm@2000c00 {

precompiled-trees/README.md

@@ -0,0 +1,29 @@
+# Precompiled device trees:
+Each folder contains a `.dtb` file, which is the compiled device tree itself, plus a `.dts` with the original source and a `.gpio` file showing the GPIO pin mappings.
+
+## Generic
+[./generic](The generic device tree I will use in my project, suitable for many occasions)
+* Has 2x UART (plus the console uart), 2x I2C. 1xSPI
+* 12 unassigned GPIO pins
+
+## Serial
+[./serial](Four UART interfaces *and* Four I2C interfaces)
+* Has 4x UART (plus the console uart), 4x I2C
+* UART3 has RTC/CTS pins available too
+* 10 unassigned GPIO pins
+
+## SPI
+[./spi](SPI plus Serial interfaces)
+* Has 3x UART (plus the console uart), 3x I2C. 1xSPI
+* 8 unassigned GPIO pins
+
+## SunXI
+[./sunxi](Vanilla, unpopulated, upstream)
+* Has the console uart, nothing more
+* *26 unassigned GPIO pins!*
+
+## AllWinner Nezha
+[./allwinner-nezha](DO NOT USE)
+* Included for completeness, this is the default device tree you get with the Ubuntu image.
+* Has the console uart, 1x I2C. 1xSPI
+* 15 unassigned GPIO pins, 3 pre-assigned to pinctl

precompiled-trees/allwinner-nezha/6.8.0-31-allwinner-nezha.gpio

@@ -0,0 +1,32 @@
+
+                MangoPI MQ Pro GPIO header (dtb name: Allwinner D1 Nezha)
+
+Gpio Header:
+                        func   des  pin       pin  des   func                              
+                               3v3   1 --o o-- 2   5v                                      
+                  free (205)  PG13   3 --o o-- 4   5v                                      
+  gpio (2000000.pinctrl:204)  PG12   5 --o o-- 6   gnd                                     
+                   free (39)   PB7   7 --o o-- 8   PB8   uart0 (2500000.serial:40)         
+                               gnd   9 --o o-- 10  PB9   uart0 (2500000.serial:41)         
+  gpio (2000000.pinctrl:117)  PD21  11 --o o-- 12  PB5   free (37)                         
+                  free (118)  PD22  13 --o o-- 14  gnd                                     
+       i2c2 (2502800.i2c:32)   PB0  15 --o o-- 16  PB1   i2c2 (2502800.i2c:33)             
+                               3v3  17 --o o-- 18  PD14  spi1 (4026000.spi:110)            
+      spi1 (4026000.spi:108)  PD12  19 --o o-- 20  gnd                                     
+      spi1 (4026000.spi:109)  PD13  21 --o o-- 22  PC1   free (65)                         
+      spi1 (4026000.spi:107)  PD11  23 --o o-- 24  PD10  spi1 (4026000.spi:106)            
+                               gnd  25 --o o-- 26  PD15  spi1 (4026000.spi:111)            
+                  free (145)  PE17  27 --o o-- 28  PE16  free (144)                        
+                   free (42)  PB10  29 --o o-- 30  gnd                                     
+                   free (43)  PB11  31 --o o-- 32  PC0   ledc (2008000.led-controller:64)  
+                   free (44)  PB12  33 --o o-- 34  gnd                                     
+                   free (38)   PB6  35 --o o-- 36  PB2   free (34)                         
+                  free (113)  PD17  37 --o o-- 38  PB3   free (35)                         
+                               gnd  39 --o o-- 40  PB4   free (36)                         
+
+Other gpio outputs of interest:
+-- PD18: Blue Status Led - free (114)
+
+Notes:
+- I2C pins 3,5,27 and 28 (PG13, PG12, PE17 and PE16) have 10K pullup resistors to 3v3
+- The Status LED (PD18) is common with the LED_PWM pin on the DSI/LVDS output

precompiled-trees/generic/6.8.0-31-generic.dts

@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: (GPL-2.0+ or MIT)
+// Copyright (C) 2022 Samuel Holland <samuel@sholland.org>
+
+/dts-v1/;
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/leds/common.h>
+#include <dt-bindings/pwm/pwm.h>
+
+#include "sun20i-d1.dtsi"
+#include "sun20i-d1-common-regulators.dtsi"
+
+/ {
+	model = "MangoPi MQ Pro";
+	compatible = "widora,mangopi-mq-pro", "allwinner,sun20i-d1";
+
+	aliases {
+		ethernet0 = &rtl8723ds;
+		mmc0 = &mmc0;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	hdmi_connector: connector {
+		compatible = "hdmi-connector";
+		type = "c";
+
+		port {
+			hdmi_connector_in: endpoint {
+				remote-endpoint = <&hdmi_out_connector>;
+			};
+		};
+	};
+
+
+	leds {
+		compatible = "gpio-leds";
+
+		led-0 {
+			color = <LED_COLOR_ID_BLUE>;
+			function = LED_FUNCTION_STATUS;
+			gpios = <&pio 3 18 GPIO_ACTIVE_HIGH>; /* PD18 */
+		};
+	};
+
+	reg_avdd2v8: avdd2v8 {
+		compatible = "regulator-fixed";
+		regulator-name = "avdd2v8";
+		regulator-min-microvolt = <2800000>;
+		regulator-max-microvolt = <2800000>;
+		vin-supply = <&reg_vcc_3v3>;
+	};
+
+	reg_dvdd: dvdd {
+		compatible = "regulator-fixed";
+		regulator-name = "dvdd";
+		regulator-min-microvolt = <1200000>;
+		regulator-max-microvolt = <1200000>;
+		vin-supply = <&reg_vcc_3v3>;
+	};
+
+	reg_vdd_cpu: vdd-cpu {
+		compatible = "regulator-fixed";
+		regulator-name = "vdd-cpu";
+		regulator-min-microvolt = <1100000>;
+		regulator-max-microvolt = <1100000>;
+		vin-supply = <&reg_vcc>;
+	};
+
+	wifi_pwrseq: wifi-pwrseq {
+		compatible = "mmc-pwrseq-simple";
+		reset-gpios = <&pio 6 17 GPIO_ACTIVE_LOW>; /* PG17 */
+	};
+};
+
+&cpu0 {
+	cpu-supply = <&reg_vdd_cpu>;
+};
+
+&de {
+	status = "okay";
+};
+
+&ehci1 {
+	status = "okay";
+};
+
+&hdmi {
+	status = "okay";
+};
+
+&hdmi_out {
+	hdmi_out_connector: endpoint {
+		remote-endpoint = <&hdmi_connector_in>;
+	};
+};
+
+&hdmi_phy {
+	status = "okay";
+};
+
+&mmc0 {
+	bus-width = <4>;
+	cd-gpios = <&pio 5 6 GPIO_ACTIVE_HIGH>; /* PF6 */
+	disable-wp;
+	vmmc-supply = <&reg_vcc_3v3>;
+	vqmmc-supply = <&reg_vcc_3v3>;
+	pinctrl-0 = <&mmc0_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&mmc1 {
+	bus-width = <4>;
+	mmc-pwrseq = <&wifi_pwrseq>;
+	non-removable;
+	vmmc-supply = <&reg_vcc_3v3>;
+	vqmmc-supply = <&reg_vcc_3v3>;
+	pinctrl-0 = <&mmc1_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+
+	rtl8723ds: wifi@1 {
+		reg = <1>;
+		interrupt-parent = <&pio>;
+		interrupts = <6 10 IRQ_TYPE_LEVEL_LOW>; /* PG10 */
+		interrupt-names = "host-wake";
+	};
+};
+
+&ohci1 {
+	status = "okay";
+};
+
+&pio {
+	vcc-pe-supply = <&reg_avdd2v8>;
+};
+
+&spi1 {
+	pinctrl-0 = <&spi1_pd_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&i2c0 {
+	pinctrl-0 = <&i2c0_pg12_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+/*&i2c1 {
+	pinctrl-0 = <&i2c1_pb4_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};*/
+
+/*&i2c2 {
+	pinctrl-0 = <&i2c2_pc0_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};*/
+
+&i2c3 {
+	pinctrl-0 = <&i2c3_pe16_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&uart0 {
+	pinctrl-0 = <&uart0_pb8_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&uart1 {
+	uart-has-rtscts;
+	pinctrl-0 = <&uart1_pg6_pins>, <&uart1_pg8_rts_cts_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+
+	bluetooth {
+		compatible = "realtek,rtl8723ds-bt";
+		device-wake-gpios = <&pio 6 18 GPIO_ACTIVE_HIGH>; /* PG18 */
+		enable-gpios = <&pio 6 15 GPIO_ACTIVE_HIGH>; /* PG15 */
+		host-wake-gpios = <&pio 6 14 GPIO_ACTIVE_HIGH>; /* PG14 */
+	};
+};
+
+&uart2 {
+	pinctrl-0 = <&uart2_pc0_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+/*&uart3 {
+	uart-has-rtscts;
+	pinctrl-0 = <&uart3_pd10_pins>, <&uart3_pd13_rts_cts_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};*/
+
+&uart4 {
+	pinctrl-0 = <&uart4_pb2_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+/*&uart5 {
+	pinctrl-0 = <&uart5_pb4_pins>;
+	pinctrl-names = "default";
+	status = "okay";
+};*/
+
+&pwm {
+	//pinctrl-0 = <&pwm0_pb12_pin>, <&pwm2_pd18_pin>;
+	pinctrl-0 = <&pwm0_pb12_pin>;
+	pinctrl-names = "default";
+	status = "okay";
+};
+
+&usb_otg {
+	dr_mode = "peripheral";
+	status = "okay";
+};
+
+&usbphy {
+	usb0_vbus-supply = <&reg_vcc>;
+	status = "okay";
+};

precompiled-trees/generic/6.8.0-31-generic.gpio

@@ -0,0 +1,32 @@
+
+               MangoPI MQ Pro GPIO header (dtb name: MangoPi MQ Pro)
+
+Gpio Header:
+                        func   des  pin       pin  des   func                       
+                               3v3   1 --o o-- 2   5v                               
+      i2c0 (2502000.i2c:205)  PG13   3 --o o-- 4   5v                               
+      i2c0 (2502000.i2c:204)  PG12   5 --o o-- 6   gnd                              
+                   free (39)   PB7   7 --o o-- 8   PB8   uart0 (2500000.serial:40)  
+                               gnd   9 --o o-- 10  PB9   uart0 (2500000.serial:41)  
+                  free (117)  PD21  11 --o o-- 12  PB5   free (37)                  
+                  free (118)  PD22  13 --o o-- 14  gnd                              
+                   free (32)   PB0  15 --o o-- 16  PB1   free (33)                  
+                               3v3  17 --o o-- 18  PD14  spi1 (4026000.spi:110)     
+      spi1 (4026000.spi:108)  PD12  19 --o o-- 20  gnd                              
+      spi1 (4026000.spi:109)  PD13  21 --o o-- 22  PC1   uart2 (2500800.serial:65)  
+      spi1 (4026000.spi:107)  PD11  23 --o o-- 24  PD10  spi1 (4026000.spi:106)     
+                               gnd  25 --o o-- 26  PD15  spi1 (4026000.spi:111)     
+      i2c3 (2502c00.i2c:145)  PE17  27 --o o-- 28  PE16  i2c3 (2502c00.i2c:144)     
+                   free (42)  PB10  29 --o o-- 30  gnd                              
+                   free (43)  PB11  31 --o o-- 32  PC0   uart2 (2500800.serial:64)  
+                   free (44)  PB12  33 --o o-- 34  gnd                              
+                   free (38)   PB6  35 --o o-- 36  PB2   uart4 (2501000.serial:34)  
+                  free (113)  PD17  37 --o o-- 38  PB3   uart4 (2501000.serial:35)  
+                               gnd  39 --o o-- 40  PB4   free (36)                  
+
+Other gpio outputs of interest:
+-- PD18: Blue Status Led - gpio (2000000.pinctrl:114)
+
+Notes:
+- I2C pins 3,5,27 and 28 (PG13, PG12, PE17 and PE16) have 10K pullup resistors to 3v3
+- The Status LED (PD18) is common with the LED_PWM pin on the DSI/LVDS output

precompiled-trees/serial/6.8.0-31-mqpro-serial.gpio

@@ -0,0 +1,32 @@
+
+               MangoPI MQ Pro GPIO header (dtb name: MangoPi MQ Pro)
+
+Gpio Header:
+                        func   des  pin       pin  des   func                        
+                               3v3   1 --o o-- 2   5v                                
+      i2c0 (2502000.i2c:205)  PG13   3 --o o-- 4   5v                                
+      i2c0 (2502000.i2c:204)  PG12   5 --o o-- 6   gnd                               
+                   free (39)   PB7   7 --o o-- 8   PB8   uart0 (2500000.serial:40)   
+                               gnd   9 --o o-- 10  PB9   uart0 (2500000.serial:41)   
+                  free (117)  PD21  11 --o o-- 12  PB5   i2c1 (2502400.i2c:37)       
+                  free (118)  PD22  13 --o o-- 14  gnd                               
+   uart2 (2500800.serial:32)   PB0  15 --o o-- 16  PB1   uart2 (2500800.serial:33)   
+                               3v3  17 --o o-- 18  PD14  uart3 (2500c00.serial:110)  
+                  free (108)  PD12  19 --o o-- 20  gnd                               
+  uart3 (2500c00.serial:109)  PD13  21 --o o-- 22  PC1   i2c2 (2502800.i2c:65)       
+  uart3 (2500c00.serial:107)  PD11  23 --o o-- 24  PD10  uart3 (2500c00.serial:106)  
+                               gnd  25 --o o-- 26  PD15  free (111)                  
+      i2c3 (2502c00.i2c:145)  PE17  27 --o o-- 28  PE16  i2c3 (2502c00.i2c:144)      
+                   free (42)  PB10  29 --o o-- 30  gnd                               
+                   free (43)  PB11  31 --o o-- 32  PC0   i2c2 (2502800.i2c:64)       
+                   free (44)  PB12  33 --o o-- 34  gnd                               
+                   free (38)   PB6  35 --o o-- 36  PB2   uart4 (2501000.serial:34)   
+                  free (113)  PD17  37 --o o-- 38  PB3   uart4 (2501000.serial:35)   
+                               gnd  39 --o o-- 40  PB4   i2c1 (2502400.i2c:36)       
+
+Other gpio outputs of interest:
+-- PD18: Blue Status Led - gpio (2000000.pinctrl:114)
+
+Notes:
+- I2C pins 3,5,27 and 28 (PG13, PG12, PE17 and PE16) have 10K pullup resistors to 3v3
+- The Status LED (PD18) is common with the LED_PWM pin on the DSI/LVDS output

precompiled-trees/spi/6.8.0-31-mqpro-spi.gpio

@@ -0,0 +1,32 @@
+
+               MangoPI MQ Pro GPIO header (dtb name: MangoPi MQ Pro)
+
+Gpio Header:
+                        func   des  pin       pin  des   func                       
+                               3v3   1 --o o-- 2   5v                               
+      i2c0 (2502000.i2c:205)  PG13   3 --o o-- 4   5v                               
+      i2c0 (2502000.i2c:204)  PG12   5 --o o-- 6   gnd                              
+                   free (39)   PB7   7 --o o-- 8   PB8   uart0 (2500000.serial:40)  
+                               gnd   9 --o o-- 10  PB9   uart0 (2500000.serial:41)  
+                  free (117)  PD21  11 --o o-- 12  PB5   uart5 (2501400.serial:37)  
+                  free (118)  PD22  13 --o o-- 14  gnd                              
+   uart2 (2500800.serial:32)   PB0  15 --o o-- 16  PB1   uart2 (2500800.serial:33)  
+                               3v3  17 --o o-- 18  PD14  spi1 (4026000.spi:110)     
+      spi1 (4026000.spi:108)  PD12  19 --o o-- 20  gnd                              
+      spi1 (4026000.spi:109)  PD13  21 --o o-- 22  PC1   i2c2 (2502800.i2c:65)      
+      spi1 (4026000.spi:107)  PD11  23 --o o-- 24  PD10  spi1 (4026000.spi:106)     
+                               gnd  25 --o o-- 26  PD15  spi1 (4026000.spi:111)     
+      i2c3 (2502c00.i2c:145)  PE17  27 --o o-- 28  PE16  i2c3 (2502c00.i2c:144)     
+                   free (42)  PB10  29 --o o-- 30  gnd                              
+                   free (43)  PB11  31 --o o-- 32  PC0   i2c2 (2502800.i2c:64)      
+                   free (44)  PB12  33 --o o-- 34  gnd                              
+                   free (38)   PB6  35 --o o-- 36  PB2   uart4 (2501000.serial:34)  
+                  free (113)  PD17  37 --o o-- 38  PB3   uart4 (2501000.serial:35)  
+                               gnd  39 --o o-- 40  PB4   uart5 (2501400.serial:36)  
+
+Other gpio outputs of interest:
+-- PD18: Blue Status Led - gpio (2000000.pinctrl:114)
+
+Notes:
+- I2C pins 3,5,27 and 28 (PG13, PG12, PE17 and PE16) have 10K pullup resistors to 3v3
+- The Status LED (PD18) is common with the LED_PWM pin on the DSI/LVDS output

precompiled-trees/sunxi/6.8.0-31-mqpro-sunxi.gpio

@@ -0,0 +1,32 @@
+
+       MangoPI MQ Pro GPIO header (dtb name: MangoPi MQ Pro)
+
+Gpio Header:
+        func   des  pin       pin  des   func                       
+               3v3   1 --o o-- 2   5v                               
+  free (205)  PG13   3 --o o-- 4   5v                               
+  free (204)  PG12   5 --o o-- 6   gnd                              
+   free (39)   PB7   7 --o o-- 8   PB8   uart0 (2500000.serial:40)  
+               gnd   9 --o o-- 10  PB9   uart0 (2500000.serial:41)  
+  free (117)  PD21  11 --o o-- 12  PB5   free (37)                  
+  free (118)  PD22  13 --o o-- 14  gnd                              
+   free (32)   PB0  15 --o o-- 16  PB1   free (33)                  
+               3v3  17 --o o-- 18  PD14  free (110)                 
+  free (108)  PD12  19 --o o-- 20  gnd                              
+  free (109)  PD13  21 --o o-- 22  PC1   free (65)                  
+  free (107)  PD11  23 --o o-- 24  PD10  free (106)                 
+               gnd  25 --o o-- 26  PD15  free (111)                 
+  free (145)  PE17  27 --o o-- 28  PE16  free (144)                 
+   free (42)  PB10  29 --o o-- 30  gnd                              
+   free (43)  PB11  31 --o o-- 32  PC0   free (64)                  
+   free (44)  PB12  33 --o o-- 34  gnd                              
+   free (38)   PB6  35 --o o-- 36  PB2   free (34)                  
+  free (113)  PD17  37 --o o-- 38  PB3   free (35)                  
+               gnd  39 --o o-- 40  PB4   free (36)                  
+
+Other gpio outputs of interest:
+-- PD18: Blue Status Led - free (114)
+
+Notes:
+- I2C pins 3,5,27 and 28 (PG13, PG12, PE17 and PE16) have 10K pullup resistors to 3v3
+- The Status LED (PD18) is common with the LED_PWM pin on the DSI/LVDS output