Basic proof of concept - has light indexed by rust code

Dockerfile

@@ -4,12 +4,19 @@ run apt-get update && apt-get install -y \
   sudo \
   git \
   python3-pip \
-  dos2unix
+  dos2unix \
+  curl
 
 run python3 -m pip install --user qmk
 
 env PATH="/root/.local/bin:${PATH}"
 run qmk setup -y -H /qmk_firmware
 
+run curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -t thumbv7em-none-eabihf -y
+env PATH="/root/.cargo/bin/:${PATH}"
+
+copy ./compile.sh /usr/bin/compile.sh
+run dos2unix /usr/bin/compile.sh
+run chmod +x /usr/bin/compile.sh
 copy ./keymap/* /qmk_firmware/keyboards/massdrop/alt/keymaps/ashe/
 run find /qmk_firmware/keyboards/massdrop/alt/keymaps/ashe | xargs dos2unix

build.sh

@@ -8,7 +8,7 @@ IMAGE=$(docker build -q .)
 docker run -it \
   --mount type=bind,src=$(pwd)/out,dst=/out \
   $IMAGE \
-  sh -c 'cd /qmk_firmware && qmk compile -kb massdrop/alt -km ashe && cp massdrop_alt_ashe.bin /out'
+  sh -c compile.sh
 
 cp out/massdrop_alt_ashe.bin ~/bin/Massdrop/qmk/massdrop_alt_ashe.bin
 cd ~/bin/Massdrop/

compile.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+set -e
+
+cd /qmk_firmware/
+rustc --emit=obj --target=thumbv7em-none-eabihf --codegen panic=abort -o test.o ./keyboards/massdrop/alt/keymaps/ashe/test.rs
+
+cd /qmk_firmware
+qmk compile -kb massdrop/alt -km ashe
+cp massdrop_alt_ashe.bin /out

keymap/pomodoro.c

@@ -7,10 +7,14 @@
 #define POM_COMPLETE_INDEX POM_CURRENT_INDEX + POM_LIGHT_COUNT + 1
 #define POM_DURATION 1500 /* 25 * 60 */
 
+uint8_t test_function(void);
+
 void draw_pom(void) {
     static bool blink_on;
     static short last_pos;
 
+    const uint8_t test_val = test_function();
+
     const uint8_t complete_hsv[3] = {HSV_TEAL};
     const uint8_t current_hsv[3] = {HSV_GOLDENROD};
     const uint8_t hidden_hsv[3] = C_MODI;
@@ -36,6 +40,8 @@ void draw_pom(void) {
         hsv_matrix_set_color(completed_position, hidden_hsv);
     }
 
+    hsv_matrix_set_color(POM_COMPLETE_INDEX + test_val - 1, complete_hsv);
+
     if (current_pom_state == STOPPED)
         return;
 

keymap/pomodoro.h

@@ -13,4 +13,6 @@ short pom_current_secs;
 uint32_t pom_second_start;
 
 void draw_pom(void);
-void count_pom(void);
+void count_pom(void);
+
+uint8_t test_function(void);

keymap/rules.mk

@@ -14,4 +14,5 @@ EXTRAKEY_ENABLE = yes			# Audio control and System control
 # COMBO_ENABLE					# Key combo feature
 # LEADER_ENABLE					# Enable leader key chording
 
-SRC += lighting_funcs.c pomodoro.c
+SRC += lighting_funcs.c pomodoro.c
+LIB_SRC += test.o

keymap/test.rs

@@ -0,0 +1,14 @@
+#![no_std]
+#![no_builtins]
+#![crate_type = "staticlib"]
+#![allow(dead_code)]
+
+#[panic_handler]
+fn my_panic(_info: &core::panic::PanicInfo) -> ! {
+    loop {}
+}
+
+#[no_mangle]
+pub extern "C" fn test_function() -> u8 {
+  2
+}