Add dynamic keymap config

src/board/system76/common/keymap.c

@@ -0,0 +1,74 @@
+#include <board/flash.h>
+#include <board/keymap.h>
+
+uint16_t __xdata DYNAMIC_KEYMAP[KM_LAY][KM_OUT][KM_IN];
+
+// Config is in the last sector of flash
+const uint32_t CONFIG_ADDR = 0x1FC00;
+// Signature is the size of the keymap
+const uint16_t CONFIG_SIGNATURE = sizeof(DYNAMIC_KEYMAP);
+
+void keymap_init(void) {
+    if (!keymap_load_config()) {
+        keymap_load_default();
+    }
+}
+
+void keymap_load_default(void) {
+    for (int layer = 0; layer < KM_LAY; layer++) {
+        for (int output = 0; output < KM_OUT; output++) {
+            for (int input = 0; input < KM_IN; input++) {
+                DYNAMIC_KEYMAP[layer][output][input] = KEYMAP[layer][output][input];
+            }
+        }
+    }
+}
+
+bool keymap_erase_config(void) {
+    // This will erase 1024 bytes
+    flash_erase(CONFIG_ADDR);
+
+    // Verify signature is erased
+    return flash_read_u16(CONFIG_ADDR) == 0xFFFF;
+}
+
+bool keymap_load_config(void) {
+    // Check signature
+    if (flash_read_u16(CONFIG_ADDR) != CONFIG_SIGNATURE) return false;
+
+    // Read the keymap if signature is valid
+    flash_read(CONFIG_ADDR + 2, (uint8_t *)DYNAMIC_KEYMAP, sizeof(DYNAMIC_KEYMAP));
+    return true;
+}
+
+bool keymap_save_config(void) {
+    // Erase config region
+    if (!keymap_erase_config()) return false;
+
+    // Write the keymap
+    flash_write(CONFIG_ADDR + 2, (uint8_t *)DYNAMIC_KEYMAP, sizeof(DYNAMIC_KEYMAP));
+
+    // Write the length of the keymap, as a signature
+    flash_write_u16(CONFIG_ADDR, CONFIG_SIGNATURE);
+
+    // Verify signature is valid
+    return flash_read_u16(CONFIG_ADDR) == CONFIG_SIGNATURE;
+}
+
+bool keymap_get(int layer, int output, int input, uint16_t * value) {
+    if (layer < KM_LAY && output < KM_OUT && input < KM_IN) {
+        *value = DYNAMIC_KEYMAP[layer][output][input];
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool keymap_set(int layer, int output, int input, uint16_t value) {
+    if (layer < KM_LAY && output < KM_OUT && input < KM_IN) {
+        DYNAMIC_KEYMAP[layer][output][input] = value;
+        return true;
+    } else {
+        return false;
+    }
+}