diff --git a/backend/fbdev.c b/backend/fbdev.c
index f015fa3..a48900c 100644
--- a/backend/fbdev.c
+++ b/backend/fbdev.c
@@ -123,21 +123,21 @@ static bool twin_fbdev_work(void *closure)
     return true;
 }
 
-static bool twin_fbdev_is_rgb565(twin_fbdev_t *tx)
+static inline bool twin_fbdev_is_rgb565(twin_fbdev_t *tx)
 {
     return tx->fb_var.red.offset == 11 && tx->fb_var.red.length == 5 &&
            tx->fb_var.green.offset == 5 && tx->fb_var.green.length == 6 &&
            tx->fb_var.blue.offset == 0 && tx->fb_var.blue.length == 5;
 }
 
-static bool twin_fbdev_is_rgb888(twin_fbdev_t *tx)
+static inline bool twin_fbdev_is_rgb888(twin_fbdev_t *tx)
 {
     return tx->fb_var.red.offset == 16 && tx->fb_var.red.length == 8 &&
            tx->fb_var.green.offset == 8 && tx->fb_var.green.length == 8 &&
            tx->fb_var.blue.offset == 0 && tx->fb_var.blue.length == 8;
 }
 
-static bool twin_fbdev_is_argb32(twin_fbdev_t *tx)
+static inline bool twin_fbdev_is_argb32(twin_fbdev_t *tx)
 {
     return tx->fb_var.red.offset == 16 && tx->fb_var.red.length == 8 &&
            tx->fb_var.green.offset == 8 && tx->fb_var.green.length == 8 &&
@@ -169,19 +169,19 @@ static bool twin_fbdev_apply_config(twin_fbdev_t *tx)
 
     /* Examine the framebuffer format */
     switch (tx->fb_var.bits_per_pixel) {
-    case 16:  // RGB565
+    case 16: /* RGB565 */
         if (!twin_fbdev_is_rgb565(tx)) {
             log_error("Invalid framebuffer format for 16 bpp");
             return false;
         }
         break;
-    case 24:  // RGB888
+    case 24: /* RGB888 */
         if (!twin_fbdev_is_rgb888(tx)) {
             log_error("Invalid framebuffer format for 24 bpp");
             return false;
         }
         break;
-    case 32:  // ARGB32
+    case 32: /* ARGB32 */
         if (!twin_fbdev_is_argb32(tx)) {
             log_error("Invalid framebuffer format for 32 bpp");
             return false;