diff --git a/.gitmodules b/.gitmodules
index d687c6cf3b..32f30f761c 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -73,3 +73,7 @@
 [submodule "ports/nrf/nrfx"]
 	path = ports/nrf/nrfx
 	url = https://github.com/NordicSemiconductor/nrfx.git
+[submodule "lib/tinyusb"]
+	path = lib/tinyusb
+	url = git@github.com:hathach/tinyusb.git
+	branch = develop
diff --git a/lib/tinyusb b/lib/tinyusb
new file mode 160000
index 0000000000..1faf0a81e4
--- /dev/null
+++ b/lib/tinyusb
@@ -0,0 +1 @@
+Subproject commit 1faf0a81e4ef7176f152165fe46ff65b598d09ce
diff --git a/ports/nrf/boards/bluefruit_nrf52840_s140_6.0.0.ld b/ports/nrf/boards/bluefruit_nrf52840_s140_6.0.0.ld
index 1865092852..fbc87801f4 100644
--- a/ports/nrf/boards/bluefruit_nrf52840_s140_6.0.0.ld
+++ b/ports/nrf/boards/bluefruit_nrf52840_s140_6.0.0.ld
@@ -7,7 +7,7 @@
     ----------  ---------- ------- -----------------------------------------
     0x000FF000..0x000FFFFF (  4KB) Bootloader Settings
     0x000FE000..0x000FEFFF (  4KB) Master Boot Record Params
-    0x000F4000..0x000FDFFF ( 40KB) Serial + OTA Bootloader
+    0x000F4000..0x000FDFFF ( 40KB) Bootloader (UF2 + CDC + OTA)
 
     0x000ED000..0x000F3FFF (28KB ) Private Config Data (Bonding, Keys, etc.)
     0x000AD000..0x000ECFFF (256KB) User Filesystem