From e81b5f6546771580203e9fc1545ff4ece44d6e94 Mon Sep 17 00:00:00 2001
From: Joel Challis <git@zvecr.com>
Date: Thu, 25 May 2023 23:07:47 +0100
Subject: [PATCH] Implement UF2 device type id extension tag (#21029)

---
 builddefs/common_rules.mk |  3 ++-
 util/uf2conv.py           | 10 ++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/builddefs/common_rules.mk b/builddefs/common_rules.mk
index e993cc350eaa..816eac49ae8f 100644
--- a/builddefs/common_rules.mk
+++ b/builddefs/common_rules.mk
@@ -152,6 +152,7 @@ endif
 # To produce a UF2 file in your build, add to your keyboard's rules.mk:
 #      FIRMWARE_FORMAT = uf2
 UF2CONV = $(TOP_DIR)/util/uf2conv.py
+UF2CONV_ARGS ?=
 UF2_FAMILY ?= 0x0
 
 # Compiler flags to generate dependency files.
@@ -219,7 +220,7 @@ gccversion :
 	@$(BUILD_CMD)
 
 %.uf2: %.elf
-	$(eval CMD=$(HEX) $< $(BUILD_DIR)/$(TARGET).tmp && $(UF2CONV) $(BUILD_DIR)/$(TARGET).tmp --output $@ --convert --family $(UF2_FAMILY) >/dev/null 2>&1)
+	$(eval CMD=$(HEX) $< $(BUILD_DIR)/$(TARGET).tmp && $(UF2CONV) $(UF2CONV_ARGS) $(BUILD_DIR)/$(TARGET).tmp --output $@ --convert --family $(UF2_FAMILY) >/dev/null 2>&1)
 	#@$(SILENT) || printf "$(MSG_EXECUTING) '$(CMD)':\n"
 	@$(SILENT) || printf "$(MSG_UF2) $@" | $(AWK_CMD)
 	@$(BUILD_CMD)
diff --git a/util/uf2conv.py b/util/uf2conv.py
index 52d3861cba0c..578b2b49772d 100755
--- a/util/uf2conv.py
+++ b/util/uf2conv.py
@@ -151,10 +151,15 @@ def encode(self, blockno, numblocks):
         flags = 0x0
         if familyid:
             flags |= 0x2000
+        if devicetype:
+            flags |= 0x8000
         hd = struct.pack("<IIIIIIII",
             UF2_MAGIC_START0, UF2_MAGIC_START1,
             flags, self.addr, 256, blockno, numblocks, familyid)
         hd += self.bytes[0:256]
+        if devicetype:
+            hd += bytearray(b'\x08\x29\xa7\xc8')
+            hd += bytearray(devicetype.to_bytes(4, 'little'))
         while len(hd) < 512 - 4:
             hd += b"\x00"
         hd += struct.pack("<I", UF2_MAGIC_END)
@@ -283,6 +288,8 @@ def error(msg):
     parser.add_argument('-f', '--family', dest='family', type=str,
                         default="0x0",
                         help='specify familyID - number or name (default: 0x0)')
+    parser.add_argument('-t' , '--device-type', dest='devicetype', type=str,
+                        help='specify deviceTypeID extension tag - number')
     parser.add_argument('-o', '--output', metavar="FILE", dest='output', type=str,
                         help='write output to named file; defaults to "flash.uf2" or "flash.bin" where sensible')
     parser.add_argument('-d', '--device', dest="device_path",
@@ -312,6 +319,9 @@ def error(msg):
         except ValueError:
             error("Family ID needs to be a number or one of: " + ", ".join(families.keys()))
 
+    global devicetype
+    devicetype = int(args.devicetype, 0) if args.devicetype else None
+
     if args.list:
         list_drives()
     else: